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MONTHLY REVIEW

Published by the
American Electroplaters Society
Publication and Editorial Office
3040 Diversy Ave., Chicago

VOL. XVII    JULY, 1930    No. 7


EDITORIAL

To the members of the American Electro-Platers Society: It gives me great pleasure to present to you the first issue of the Review under jurisdiction of four new officers for term 1930-931.

It will be our great aim to equal previous work of this publication, and to surpass same as is expected of each succeeding administration if progress is to be made by our Society.

We thank all past officers for their kind assistance in trying to aid us in getting started off with speed and accuracy, and hope for the same courtesies afforded this office by the branch secretaries, officers of branches, and the patience of our members, and I can assure you the same high standard of efficiency shall be maintained by the Monthly Review.

Page 2 contains full information on new officers. Kindly note these and address all your communications to proper officers and this will promote the efficiency of these new officers and avoid usual confusion in change of officers.

The branch officers and members will also note that the Society is now incorporated under the laws of New Jersey. Also that our constitution remains the same with such changes as are legally made at conventions per provisions thereof. Also note that the 1st change is to strike out of constitution Section 3, Article XII, page 23, by majority vote of delegates.


HYDROGEN PITTING AND PEALING OF NICKEL AND COPPER PLATED DEPOSITS UPON HIGH CARBON AND OTHER STEELS

By Charles H. Proctor

Hydrogen pitting and pealing of the copper and nickel plated deposits upon high carbon and other steels at intervals, presents serious problems under the present intensive production of such plated products previous to chromium plating in the automotive and other allied industries.

Looking backwards thirty years or more ago when the double nickel salt solution (nickel and ammonium sulphate) was exclusively used and operated under low current densities of not more than 5 amperes per square foot of surface area, no pitting of the nickel plated finish occurred, but as I review some of the problems I met with in the late eighties, 1888 to 1890 and 1892, I now know that hydrogen was then a problem as it is today, but we did not know then its detrimental influence as it is known today.

I have talked with many of the old time platers in Connecticut, whose fathers were platers before them; men who knew the art of plating in every detail and had to produce every type of finish and in those early years there were no elaborate colored lacquers of the Duco and other types to assist in the production of contrasting effects in the production of art metal goods. The plater had to produce his own colors, principally with a so-called ”French Varnish” base which consisted of grain alcohol in which was dissolved gum copal and other hard gums. Such men never mentioned hydrogen pitting or pealing of their nickel plated deposits. If such problems occurred then the problem was always laid at the door of defective cleaning or other chemical treatment of the basic steel or cast or malleable iron products, but there is no question that hydrogen has always been a disturbing factor in nickel plating operations even as it is today, but upon a more extensive and more serious basic due to intensive production from high density nickel and copper plating solutions.

Going back to the years 1888 to 1890, I was employed by the Ansonia Brass and Copper Company, Ansonia, Conn. This firm is now a part of the Anaconda Copper & Brass Corporation, who succeeded the American Brass Corporation. I then had charge of all plating and polishing and also lacquering departments and we produced about every type of finish that it was possible to produce and this means all the antique finishes that are produced today on electric fixtures and art goods in general. We had problems then and they had to be overcome because we had to produce acceptable goods even as platers must produce today. This was in the days before volt and ampere meters, before chemical control had become a recognized factor in the operation of modern electroplating solutions, and before chemistry had become a recognized factor. Still we did produce results. How we did it is still a great problem but we carried the art along even as our fathers, who were platers, did before us.

It was in 1881889 when I ran into the greatest problem of all my extensive plating experience. We had to plate highly polished copper- sheets some 22 inches by 54 inches in size, and 1/16 inch thick, on both sides with an adherent deposit of nickel that would not strip or peal and that would withstand temperatures of three hundred degrees F. or more; beneath a hydraulic pressure of 20,000 pounds or more. Such sheets as outlined were used in the manufacture of polished celluloid in Arlington and Newark, N. J. The former plant is now controlled by the DuPont Corporation. Matt finished celluloid had to be produced as well as the polished material, so the nickel plated copper sheets had to be sand blasted after nickel plating and steam pressure was used for the purpose instead of compressed air as now used.

When we first started operations in the nickel plating of such sheets all seemed to go along well. The sheets were trimmed on the extreme ends and sides to conform with the exact size required. The sheets were then polished to a very high lustre with buff wheels with a face surface area wider than the sheets themselves. After polishing the sheets were packed with canton flannel sheets and blotting paper pads between, to avoid any possible scratching or abrasion of the sheets in transit. Such defects would always show up in the polished celluloid sheet having been transmitted from the nickel plated surface.

Later on problems developed at intervals. Nickel plated copper sheets were apparently perfect when leaving our plant. The nickel did not peal from the sheared strips when bent at right angles until crystallization occurred and the strip broken in two nor in the final polishing operation did the nickel separate from the sheets, yet at intervals when the sheets were placed in production due to heat expansion and high pressure, the nickel would be found to separate from the base metal and adhere to the celluloid sheets when removed from the hydraulic presses.

Every operation was carefully gone over in detail when such problems occurred because it was a very costly one for my firm as they had to replace such sheets and stand for every incidental expense connected with their failure, so each shipment that failed ran into thousands of dollars.

Cleansing was thoroughly studied, removal of any oxide even of a superficial nature was carefully gone into. The current was carefully controlled under then existing conditions, but the problem still continued at intervals. We had a metallurgical laboratory in charge of my late and lamented friend, Dr. George Grower. He went deeply into the solutions and made a check-up to prove that there was nothing wrong with them but to no avail. Finally the dawn came out of the darkness and I saw the true basis of my problem; we did not know how to control it but I did in my own way. I decided to add nothing to the solution contained in a tank 24 feet long, 36 inches deep and 24 inches wide, except commercially pure ammonium sulphate and water and keep the nickel solution exclusively for plating the copper sheets.

It is strange, however, that before I discovered the probable cause of my problem, I had plated hundreds of thousands of nickel plated brass clock cases in the same solution and never had the least trouble of pealing of the nickel deposit.

We still meet with similar problems and some still think that the cleansing, or the pH of the solution, or the current control is the cause of pitting or pealing, but I do not. If this theory was true then my firm would never have developed the extensive business for sodium perborate I first advocated for hydrogen control and 25 to 100 volume hydrogen peroxide for the same purpose of hydrogen control in nickel plating solutions.

The modern hydrogen pitting and pealing of nickel plated deposits which has caused an endless amount of trouble in the automobile and accessory industries had its origin with the introduction of the single nickel salt solution. The resultant high metal content of such solutions and high current densities carried upon the surface area which influenced hydrogen deposition or occlusion such as pitting.

When pitting first occurred with nickel pealing it was decided that heating of the concentrated nickel solution to 120 deg. Fahr. would expand the hydrogen gases or bubbles and they would rise to the surface of the solution and pass into the atmosphere, but did not solve the problem. The filtering of the nickel solution prevented mechanical pitting but not hydrogen pitting or pealing. Filtering and air agitation by compressed air did not solve nickel plating problems.

The author failed to find any true reference to any authentic work on electro-plating written during the interim between the years of 1880 and 1895 which gave any satisfactory explanation of hydrogen pitting and pealing, its true cause and cure until Dr. Madsen of Madsenell Nickel fame discovered the detrimental influence of hydrogen. Many presumed authorities who should know better in the light of present day facts still believe such problems are due to other causes’ cleansing in particular or detrimental pH or current conditions.

Dr. Oliver P. Watts of the University of Wisconsin, whom we’ all know and admire, in his excellent address in Pitting of Nickel Plating at the annual banquet of Chicago Branch (A. E. S.) in January, 1924, summed up the causes of nickel pitting and pealing from the reports of those members of the society who were so kind as to write to him and cite their experiences with these problems, as follows:

(a) The nickel solution too acid.
(b) It is too alkaline.
(c) Imperfections in the basic metal surface.
(d) Defective cleansing of the basic metal surface.

Dr. Watts frankly admitted at the outset of his address as follows: ”Although I have used all the time that I could beg borrow or steal, I am- still unable to give you a true cure for pitting and pealing of nickel deposits.

F. E. Halberttin his excellent article, ”The Pitting and Pealing of Nickel Deposits,” published in the Brass World in October, 1907, gave the most satisfactory explanation of the cause of- such problems, but could offer no solution of the problem.

The late Emmanuel Blassett, Jr., a well known author and former member of the New York Branch (A. E. S.), wrote an excellent article in December, 1911, issue of The Metal Industry on ”The Cause and Prevention of Pitted and Rough Nickel Plated Deposits.” Mr. Blassett, however, did not solve the problem in his article.

The electrical wizard, Thomas A. Edison, was the first to solve the problem of hydrogen control of nickel plated deposits. He had found the very detrimental influence of hydrogen deposition and occlusion when endeavoring to produce perfectly malleable thin sheets of nickel by electrolysis. He obtained a U. S. Patent No. 964,096 in 1910 covering the introduction of chlorine gas into the nickel solution under pressure. The function of the chlorine so injected into the solution was to combine with the excess hydrogen and from hydrochloric acid. The free acid so formed in the solution removed the excessive amounts of hydrogen that was the cause of defective malleable nickel deposits and became a factor in increased anodic reduction in the formation of nickel chloride.

The value of Edison’s ideas have been amply proven during the past few years by automotive product manufacturers who have used tremendous amounts of nickel chloride which results in greater anodic reduction, greater throwing power and to a great extent hydrogen control. It was Edison’s theory of the value of chlorine which gave the writer the cue several years ago to advocate the extensive use of nickel chloride. It is not a new factor, for as early as 1880 I saw it in operation in Birmingham, England, and known as ”Double Nickel Chloride Solutions” for planting the old high bicycle parts made from steel and the cycle type which was then called the safety bicycle.

It has proven its value in the commercial plating industry in America and many serious cases of hydrogen pitting or pealing of the nickel deposit have been controlled by its aid. Nickel chloride sodium perborate or its product, hydrogen peroxide, are the real factors. It has proven to be true in a thousand plants during the past few years and has eliminated a great source of trouble to the plater and a costly disturbing factor in the plating industry as a whole. It is now possible to nickel plate steel in high density solutions, either still, automatic conveyor or mechanical barrel type, with nickel content as high as 12 ounces of metallic nickel per gallon of solution and obtain the very maximum results.

The problem of hydrogen pitting and pealing from the basic steel is nut only confined to nickel deposits but occurs when articles made from low carbon steel such as auto radiator shells and high carbon steels, such as used in the manufacture of automobile bumpers, etc., are copper plated. This has proven to be true in solving many problems I have met with in recent years, especially in copper plating from copper cyanide solution.

The copper cyanide solution that develops hydrogen pealing of the copper deposit may be an entirely normal one so far as metal and free cyanide is concerned and the inert factor as sodium carbonate may also be normal, still pealing problems may result even with the most careful chemical treatment of the steel articles to be plated. Such a condition developed in a large automobile plant in Toledo, Ohio, three years ago. For nearly a week the copper deposit was pealing from radiator shells when the deposit was polished to a lustre finish as a basis for the final nickel and chromium deposit. In many instances the pealing would not show up until the nickel deposit had been applied and buffed to a lustre finish, then again only when the chromium had been applied.

It was first inferred that the cleansing of the steel previous to plating was defective although the same type cleaner had previously given ideal results and no plating problems. The cleaner is a well known product of a Michigan firm, but the conclusions were that the cleaning was the true cause of the pealing problem. So the cleaner expert was called in and for nearly a week labored consistently to cleanse the product satisfactorily. I happened to be in the Ohio city where the plant is located and as usual called upon the firm which was having the trouble outlined. The matter was brought to the writer’s attention and he at once diagnosed the problem as due to hydrogen and the copper cyanide solution was treated accordingly and it was also decided to treat the nickel solution for a possibility of hydrogen occlusion, although no trouble had occurred. The addition of sodium bisulphite to the copper cyanide solution up to two ounces per gallon of solution was made in proportion of one-half ounce at a time. The copper was thus reduced from the cupric to the cuprous state and the hydrogen gas, which caused the trouble, was released, due to the reaction of the sulphurous acid the salt contained and has never re-occurred. The cleaner expert returned during the day and when told that the problems had been overcome, stated he thought that the last addition he made to the latest cleaner installed would do the trick, but he was advised later of the true cause of the trouble

Within the past two months friends of the author have in stalled in a plant in the Pittsburgh, Pa., district, a complete automatic conveyor unit for nickel, copper and nickel plating automobile bumpers. The mechanical features of this unit are perfect in united operation and capable, under forced conditions, of plating 17 carloads of automobile bumpers per day at the maximum current densities.

I was requested to write up the detailed information covering all solutions, including: alkaline cleansing, acid pickling, nickel strike, copper cyanide and final nickel deposit. The detail included the several water washings, both cold and hot, as required. The formula outlined for the plating solutions were as follows:

Nickel Solution (Strike and Regular):
Water 1 gallon
Single nickel salts 50 ounces
Nickel chloride 4 ounces
Boracic acid 2 ounces

Voltage, 6. Amperage, from 30 to 100 per square foot of surface area.
Temperature, 110 to 120 deg. Fahr. pH, 5.4-5.6.

Copper Cyanide Solution:
Water 1 gallon
Sodium cyanide 96/98% 10 ounces
Copper cyanide 8 ounces
Sodium sulphite 4 ounces
Sodium hyposulphite 1/50 ounce

Voltage, 5 to 6. Amperage, 25 to 100 per square foot of surface area. Temperature, 120 deg. Fahr.

With absolute cleansing the high carbon steel bumpers developed pitting and slight pealing in the nickel solution and hydrogen pitting and pealing of the copper deposit. Although cleaner experts and research chemists had diagnosed the pitting and pealing problems as one of exclusive defective cleansing, still the writer decided hydrogen gas was the true cause of the problem and treated them accordingly with sodium perborate, as the hydrogen controlling factor in the two nickel solutions, and with sodium bisulphite additions in the copper cyanide solution, up to two ounces per gallon. It required a minimum of one-fourth ounce of sodium perborate administered under the procedure first outlined in this paper.

If, at any time, you are confronted with similar problems first being absolutely assured that your product is chemically clean, then the factors I have outlined will solve your problems of pitting and pealing of the nickel and copper plated deposits.

As previously stated, it was Dr. Madsen who first proposed publicly the use of hydrogen peroxide as a controlling factor for hydrogen in nickel plating solutions. He advocated from 4 to 16 cc. of a 3 per cent solution per gallon of solution, or 1 to 4 cc. per liter. The active oxygen it contains and splitting off the hydrogen peroxide combined with the hydrogen as it is generated at the cathode, and thus prevents hydrogen pitting or pealing.

Hydrogen peroxide is an unstable liquid, however, which starts to decompose as soon as it is made. Moreover, it contains only 1 1/2 per cent oxygen, the rest being water. It is, therefore, bulky and causes a great deal of expense in transportation.

It was, in order to overcome these disadvantages that I cast about to find a better source of oxygen which could be relied upon to retain its valuable oxygen until required, which would not necessitate carrying around an enormous bulk of dead matter and which would permit accurate measurement and therefore uniform results. If, besides this, such a chemical were slightly alkaline, its addition to the acid nickel solution would neutralize a part of the acid.

I found such a chemical in sodium perborate (Na BO3 + HO) which is a powder contained 10 per cent available oxygen. Its solution in water is mildly alkaline. It can be kept indefinitely without loss of strength. One pound is the equivalent of 6.7 pounds hydrogen peroxide. It costs one-third less for the oxygen it contains. Instead of from 8.8 to 35 pounds of hydrogen peroxide per 1,000 gallons of nickel solution, we take from 1 1/3 to 5 pounds of sodium perborate. The perborate should first be dissolved in warm water (100 degrees Fahr.) at the rate of 1 pound in 6 gallons. This solution is then added to the nickel bath in such quantity as experience- teaches will take care of the hydrogen evolved.

In most instances the slight alkalinity of the perborate solution is of advantage in cutting down excessive acidity of the nickel bath, but when the latter is finely regulated the perborate solution may first he acidified with hydrochloric acid until it equals the acidity of the nickel bath.

I may state that in every case I have met, the perborate has acted as expected, and has prevented hydrogen pitting or pealing, which would appear to indicate that sodium perborate accomplishes all that hydrogen peroxide does, but overcomes its disadvantages and is cheaper.


INTRODUCTION OF IRON INTO
ALKALINE CLEANING AND PLATING SOLUTIONS

Read at Washington, D. C., 1930, by F. J. Liscom Chicago Branch

How does iron get into the bath?

In what form is it held in solution?

What effect does it have on the anode?

Effect on the steel tank and steel anode rods of a silver solution?

Work is pickled in sulphuric acid—hydrochloric acid?

Neutralizing of pickling acid?

Rinse water as source of impurities in-plating solutions?

Effect of ammonium chloride in nickel solution?

Effect of ammonium chloride in acid copper solution on the anode?

Effect of chlorides in a silver bath—sodium chloride—ammonium chloride—and mixture of both?

Why the addition of sal ammoniac to cyanide solutions?

Introduction of Iron Into Alkaline Cleaning and Plating Solutions

From time to time a request for credit comes through the mail for a steel plating tank that has failed, i. e., showed signs of corrosion or actually perforated. Many tanks have been replaced with new ones only to have a repeat request for another. There have been so many steel tanks that have failed that it has become a hardship for the manufacturers. As it was realized that all of the tanks could not be defective, an investigation was started in an endeavor to find out the reason for the numerous failures. One has not far to go to find this reason if he happens to be a close observer.

Steel tanks have been used for generations as containers for cleaning solutions. We used weak solutions and low temperatures and expended much arm power at the handle of a scrub brush, but all of this has been changed, and now in this age of production we must resort to less laborious methods for cleaning the work to be plated. Therefore, we install electro-cleaners and high current densities and do the work in a fraction of the time consumed by the old method of hand scrubbing.

Now, electric cleaning is a very proper method when it is performed in an intelligent manner, but unfortunately the process has its-limitations. In the first place the tank should never be made the anode of the circuit because eventually corrosion is sure to follow. Caustic soda, soda ash, or sodium cyanide, when used as a cleaner, will cause no trouble so long as there is no salt such as sodium sulphate, trisodium phosphate, sodium chloride, or ammonium chloride present; even the sulphate and phosphate may be neglected provided there is enough caustic soda present. However, if the caustic soda has become destroyed by age, the sodium sulphate and phosphate, if present, will commence to corrode the steel tank. Chlorides, no matter what kind, will attack the steel even in the presence of much free cyanide and sodium hydroxide.

If the steel tank is the anode of the electric cleaner, the plater should know if his cleaner solution is attacking his steel tank. A simple test will apprise him of the fact. All that is necessary to do is to take a drinking glass, fill up the glass with the cleaning solution (preferably filtered), then with two pieces of wire connected to the bus bars of the dynamo place a steel nail on the other ends of the wires and dip the ends of the nails into the cleaner solution. Let the electric current flow through the solution and watch the anode nail. If the solution contains chemicals that will cause corrosion, a heavy scum will form on the anode in a very few minutes.

Trouble often occurs when you have a lot of work that must be pickled. This is done in sulphuric or muriatic acid, after which you rinse, dry, polish, and go to the cleaner. The iron or steel has iron sulphate or chloride in the pores which the cleaner neutralizes. The iron in the salt is precipitated and sodium chloride or sulphate is formed. Each day increases the amount until at last the alkali is weakened and the sodium chloride and sodium sulphate get into action, and eventually, if used as an anode, the tank goes to the junk pile.

Again, we find that some operators will take the work out of the pickle and neutralize the acid in the cleaner even without a previous rinse. Neutralizing solutions have been found that actually showed acid reaction with blue litmus paper. The remedy is obvious, and it is within your power to correct the evil.

Where work must be pickled be sure to rinse the acid away by the use of several rinse waters, neutralize the remaining acid in a strong alkali ”her than the electric cleaner, and again rinse well, and lastly take the positive connection off of the cleaner tank and install anode rods insulated from the tank and fitted with large, steel anodes. This last suggestion does not cure the evil; it only delays the day when the tank is junked unless care is taken to exclude the acid mentioned.

Acids are not the only offenders, for, where only one rinse tank has been installed, nickel sulphate gets into the cleaner and cyanide plating solutions in steel tanks by being carried from the foul rinse water. Nickel solutions also contain chlorides as well as sulphates, and these too should be rinsed away.

Avoid the use of low percentage sodium cyanide, as this often contains as much as 20 to 25 per cent sodium chloride. This sodium cyanide is satisfactory for heat treatment of steel but not for plating.

Just one more thought—perhaps you use what is termed the reverse current in the cleaner, and you think that because the work comes out of the cleaner with a dirty color you are plating out the dirt. Well, you are not. You are simply undoing what the polisher has done because of the fact that the cleaner is low in caustic and high in sulphates and chlorides of soda or ammonia, which means that you actually etch the work you are about to plate, and, if the ”dirt which you plated out” is not removed by an acid, then the plating may peel, blister, or pit.

In the old days electroplating was something of a mystery even of the best informed. All formulae said to dissolve so much of such and such chemicals and if the solution does not work then add so and so. Then the more thoughtful ones began to investigate to try to find out the why. Finally there came methods of analysis for plating solutions. These data were based on the published methods of analysis of solutions which contained only pure chemicals—at least they did when new.

However, a plating solution that has been used for a long time may have gathered some other ingredients not mentioned in the formula, such as glue, salts of other metals such as zinc and copper, cadmium in nickel solutions, iron which may appear as ferrocyanide in alkali baths, or salts of the strong acids as chlorides and sulphates. Some of these impurities exert a powerful influence even in microscopic quantities. With this thought in mind some experiments have been carried on, not necessarily to a final conclusion but to a point that indicates that we are not going into the chemical research as far as we should, which is an argument in favor of more funds for the research committee. The results of these experiments, as well as some observations, are here set down in the hopes that further work may be done by others more capable.

Some years ago our attention was called to a large cyanide brass plating solution which was working badly. An effort was made to analyze the solution for metals, carbonates, free cyanide, etc. As the analysis proceeded it became evident that there was a metal present other than copper and zinc. This metal proved to be iron. Since then solutions have come to hand from time to time that contained iron. However, little attention was paid to its presence; no attempt was made to ascertain in what form the iron was held or what effect it may have had on the deposit of copper, brass, or cadmium; or what, if any, action it had upon the anode. Very recently three cyanide solutions have come to hand, one a cadmium. Here it was noted that the steel supports of the cadmium anodes were gradually disintegrated to such an extent that they fell apart, and at low temperature (60° F. to 70° F.) small, transparent, sand-like crystals, which gave no reaction for either sulphates or carbonates, formed on the steel. Eventually they fell off and accumulated on the bottom of the tank. After these crystals were gathered and lay in the air for several days they lost their water of crystallization and a white powder resulted which was still soluble in water. When hydrochloric acid was added a green solution resulted. It was also noted that the tank was corroded at the ends to such an extent that it had to be replaced by a new tank.

Two copper solutions came to hand that contained a small amount of free cyanide—a little metallic copper. The solutions had a peculiar color. The anodes were coated over with a reddish brown, fur-like coating, which much resembled copper ferrocyanide.

Experiments have been carried on with sodium cyanide solutions to which iron salts have been purposely added in the presence of varying amounts of free sodium cyanide. Both ferrous sulphate and ferric chlorides were tried. The ”ous” salt seemed to be the most completely dissolved in cyanide, especially when there was sodium hydrate present. All of the iron salts, ”ous” or ”ic”, are not completely soluble in cyanide sodium. No matter how strong or how hot the solution is there still remains some undissolved iron precipitate in the cyanide solution with either ”ic” or ”ous” iron in-solution. When all of the iron salts have been dissolved that will dissolve there is still free cyanide present. To these iron solutions was added enough copper cyanide so that no free sodium cyanide remained. Then, when a current of 6 to 7 amperes per square foot was passed, a good deposit formed on the cathode, while the copper anode became covered with a thick coating of a mixed, blue-green solid and a reddish-brown scum. Sodium cyanide was added in quantities of 1/4 ounces per gallon until at about ounces per gallon only the reddish-brown scum was apparent on the anode. At approximately 1/4 ounces per gallon of sodium cyanide the anodes did not coat heavily at 6 to 7 amperes per square foot. To find what would be the effect of a greater current density with the same amount of free sodium cyanide, the current was increased to approximately 15 amperes per square foot, and it was found that in 15 minutes there formed on the anode a thick, heavy, reddish-brown coating, which corresponded to the color of copper ferrocyanide.

From this we gather that for a cold copper cyanide solution, where the sodium cyanide content must be kept down (in the interest of high cathode efficiency), the presence of iron will be detrimental to good anode corrosion due to the ferrocyanide formed. In warm solutions, where a much larger free sodium cyanide content can be maintained and we can still have a good cathode efficiency as well as a higher current density, it is predicted that there would still be some difficulty unless care were taken to offset the ferrocyanide with free cyanide, temperature, and current density.

Just how the iron gets into the solution in the first place is a problem. We know from experience that in some solutions (electric cleaning) when the work is being cleaned electrically on the anode or positive pole, the steel is attacked, showing the characteristic color changes peculiar to ferrous hydroxide; viz., the first color noticed is white. This is soon followed by a greenish color. Later this, when exposed to water or air, becomes the color of iron rust (ferric hydroxide?). Since this red color does not seem to go into sodium cyanide, at least not completely, it is presumed that when the ferrous hydroxide is white or in the early stage of the green color, and it is on the surface of the work, going into the warm cyanide plating solution, it is probably soluble in sodium cyanide’ at least to some extent, and forms sodium ferrocyanide. Then, if this is so, it follows that if a piece of steel or iron is pickled in an acid and not completely rinsed and neutralized the iron salts produced do undergo a chemical change to form hydrates (ous), which seemingly are soluble in cyanide and hydrate and do form sodium ferrocyanide.

Again, even if the iron salts from the pickle solution were not converted into ferrocyanide, there would at least be a chemical change between the acid radical of the pickle acids and the alkali of the cleaner, and there would form as a part of the reaction a sodium sulphate or sodium chloride, depending upon the acids used in the pickle (sulphate distinct from chloride). With these chemicals in the plating solutions in contact with the iron heating coils and the steel tank, which may get into the path of the electric current, i. e., become cathode near the back of the copper anode and anode at the end or bottom of the tank near the true cathode proper, at that portion of the tank that became the anode electro-chemical action is set up to such an extent that the steel tank becomes corroded and even perforated, exactly as described above in connection with certain electric cleaners. If, then, the white or green (ous) iron hydrate at the instant of formation is dissolved in the sodium cyanide and hydroxide of the bath, the final result will be the same; namely, the formation of sodium sulphate or sodium chloride and possibly sodium ferrocyanide.

Therefore, the obvious solution of the problem is to prevent mineral acids or salts of strong mineral acid from getting into the alkali plating solution even in small quantities, because, even after’ they have attacked the tank and at least a portion of the dissolved iron goes into solution or is precipitated as hydrate, the salt of the acid is regenerated and is free to act again, etc., ad lib. If, however, such salts are present, and they are frequently added to the solutions intentionally in the form of sodium sulphite, bisulphite, hyposulphite, sodium sulphate, ammonium chloride, etc., some provision should be made to prevent the electric current from coming into contact with the steel tank. Therefore, use rubber-lined steel tanks, which will keep down the effect of sodium sulphate or chloride on the steel tank and leave only the anodes in the solution open to the action of the chloride or sodium ferrocyanide, if present.

As it was realized that all mineral acid salts may not act the same, some tests were run which would determine which acids were the most detrimental. Then solutions of sodium cyanide with the additions were prepared, each in a separate beaker. The electrodes were of steel and the electrodes of the several cells were electrically connected in series. A current of suitable strength was passed for a period of one hour. The presence of Rochelle salts resulted in no corrosion of the steel anode. However, in the presence of sodium chloride or ammonium chloride there was a very heavy corrosion of the steel anode; yet the action of the sodium chloride was different than that of the ammonium chloride. With ammonium chloride there the iron seemed to go into solution momentarily. As this metal-charged solution came in contact with the chemicals a precipitate formed around the drops. The color of this precipitate, at first whitish, later turned to a bluish-green color and eventually became very dark brown in spots (ferric hydroxide). As the action continued a very fine example of that chemical phenomenon known as ”chemical garden” formed. As the solution filters through this precipitate or membrane to dissolve more iron at the anode, the membrane will break and the iron bearing solution will burst forth only to be confined by a new membrane at the point of the rupture. Some of the branches were as fine as a hair and extended upward for at least two inches.

In that solution where sodium chloride was used, the action on the anode was as great as where the ammonium chloride was used, but there was no chemical garden formation.

In a silver solution made from silver chloride and cyanide, to which was added some ammonium chloride, there was still another type of result at the anode. (And from this it is gathered that there is really more in this subject than appears on the face. Notwithstanding the fact that such solutions have been used for years without complaint, it does not follow that there was no reason for complaint. Probably the thought was that these conditions just had to be, as was the case with the yellow sludge in nickel solutions where 90 per cent nickel anodes were used—”it wad just there, that’s all.”) Both ammonium chloride and sodium chloride were present. The latter resulted from the reaction when silver chloride was dissolved in sodium cyanide. There formed at the anode a yellowish, ochre-like precipitate, which slipped off the anode and fell to the bottom of the beaker. Later, when this solution was taken out and stirred, it was noticed that the particles were very small (colloidal) and that they did not settle rapidly. The solution was then boiler with some sodium cyanide solution, after which it was cooled and placed back in the line, and the action on a fresh steel anode was noted. On this second run the anode scale was exactly the same as in a bath where sodium chloride alone was used. Why the anode slime should change from yellow before boiling the solution to brown after boiling it is not known, unless the boiling drove off the ammonia to form additional sodium chloride.

It begins to look as if there are certain plating solutions in which ammonium chloride may be used, while in other solutions it may be -useful; as for instance in nickel solutions where the ammonia complex seems to cause an action on the anode whereby the anode efficiency is greater than the cathode efficiency. At least the metal content of the solution does increase. However, in an acid copper solution ammonium chloride will cause a yellow copper chloride to form on the anode which is insoluble in the acid copper solution. This may be gathered and washed and dissolved in nitric acid, and with silver nitrate test solution it will react for chlorine. Again, with the presence of sodium chloride in certain types of nickel solutions where high current densities are used, it has been noticed that the sludge is rich in nickel hydrate which forms and settles at the bottom of the tank.

Later Experiments

It was noticed that in a solution known to contain ferrocyanide, sal ammoniac, and sodium cyanide, and in a silver solution which contained both sal ammoniac, sodium chloride, and sodium cyanide, the iron anode scum was of a dark blue color upon being examined in a strong light when dry (see above). When it was treated with ammonium chloride a portion of it went into solution (Prussian blue).

With ammonium chloride and cyanide and an electric current a yellow scum formed on the steel anode (see remarks above on silver). Hot caustic soda dissolved a portion of this precipitate. The solution then gave a green color with hydrochloric acid (iron). When a copper anode was put into action in this solution it gradually became covered with a red copper ferrocyanide, indicating that the iron that had been removed from the steel anode due to the presence of the ammonium chloride had been dissolved in the cyanide; or else this was done by some reaction that did cause the formation of sodium ferrocyanide. This, of course, set free the chlorine, which was then free to attack the steel tank or other iron that got in the path of the electric current. (Series.)

In the solutions of ferrocyanide, sodium cyanide, and sodium chloride, the anode scum seemed to be wholly red iron hydroxide

In a solution of sodium cyanide and sal ammoniac the copper anode gives off a green color which is expelled by more cyanide, but when the sodium cyanide becomes saturated the color of the solution and the slime from the anode indicate the ammonia copper complex and the presence of ferrocyanide, as the copper anode takes on a red color.

When only sodium cyanide is run with a steel anode there is no visible action on the steel.

Summary

Work which is pickled in hydrochloric acid, or other acid for that matter, should be well neutralized and rinsed several times in clean water before going to a plating solution.

Cleaning and alkali plating solutions should be free from all chlorides, or

The tanks should be rubber lined.

Unlined steel tanks should not be used as the positive or anode in any cleaning or plating solution.

All electric cleaning and alkali plating solutions should be tested with steel electrodes to see if the solution attacks the steel tank under the influence of the electric current.

Seemingly sodium ferrocyanide does not interfere with anode corrosion in alkali copper solutions except where the free cyanide content is low and the current density is high.

Sodium ferrocyanide in the presence of sodium cyanide does not effect the steel anode seriously.

Rochelle salts added to cyanide solution did not attack steel, but 76 per cent sodium cyanide, i. e., chloride mixture, should not be used for plating.

Ammonium chloride should not be used in acid copper solutions.

Steel tanks should be rubber lined to prevent a metal deposit on the tank back of the anode, i. e., false cathode. At some other point as the end or bottom of the tank, i. e., false anode, of chlorides are present in the solution the tank may be expected to be corroded or even perforated due to this series connection. Moral—Line steel tanks.

The object of this paper is not to tell you something but rather to start something.

Thanks are due to Dr. W. Blum and also to Mr. Harold Faint for helpful hints.


CADMIUM PLATING

Read at Detroit 1929 Annual by H. C. Pierce

This morning you heard a specific talk on cadmium plating. This goes in the other direction, and is entirely a general discussion on cadmium.

The corrosion of metals and its prevention is daily receiving more and more notice, and is today one of our major engineering problems. The numerous works and publications of recent years show the activity of the investigators in this field; a field of paramount importance, but one of the most complicated and least known in all chemistry.

The goal of the investigator in corrosion has been to thoroughly grasp the fundamental laws of corrosion, which, however, has been very difficult, as the possibilities of corrosion of industrial products are almost unlimited. It can only be predicted to what influences a material will be subjected, so that all precautionary methods of protection are more or less one sided. The progress made in this field shows that the engineer is not as helpless in combating corrosion as in former times. Ways and means can and will be found to combat this resistless attack.

An accurate estimate of the loss resulting from corrosion of the metals in common use is quite impossible. This yearly loss is known to amount to millions of dollars. Much of this loss is invisible to the casual observed, but it is only necessary to observe a few of our junk yards to have this fact forcibly brought to mind. Some part of the corroded metal is recovered as scrap, but the cost of replacing such parts far exceeds this saving. Rusting and corrosion may also impair the strength of structures and machines, thus endangering not only property, but human lives.

Aside from the actual destruction of parts, and cost of replacement, there is still another factor of extreme importance. Roughly, the loss and replacement of 1,000 tons of steel gives a depletion tons of coal, 500 tons of limestone, together with magnesite, chromite, etc. The labor required also involves a large number of man hours.

The more numerous the uses of a product, the more are the kinds of corrosive attacks to which it is subjected. The best example is that of iron and its alloys, which are used in all branches of industry and technology. The widespread use of iron has been the means of bringing forth almost countless methods for protecting iron from corrosive attacks. The method of protecting the surface depends primarily on the use to which the article will be subjected. Of the various methods used in protecting metal surfaces, metal coatings and methods of their application play a particularly important part. Various metals have been successfully used as metal coatings on other metals. Gold, silver, lead, tin, nickel, copper, brass, chromium, zinc and cadmium have all been used in an attempt to stop or to retard the resistless advance of corrosion. Each metal has its own specific properties, so that each metal has its own particular field of usefulness in this relentless battle against corrosion. Likewise, these same specific properties often limit the value of a metal as a rust proofing agent.

One metal, however, has been found to be of particular value in protecting ferrous metals against corrosion under a maximum of conditions. This metal is cadmium. Cadmium was discovered by the German Chemist Stromeyer in 1817, while investigating the peculiar yellow color of a zinc oxide. Although discovered in 1817, it is a comparatively new metal industrially. Most metals, especially those found of value in the plating industry, occur naturally in ores and are more or less easily obtained. Metallic cadmium does not occur naturally, and there is no ore of cadmium or mineral of which cadmium is the main constituent. Only certain compounds of cadmium, mainly carbonates and sulphides—are found associated in minute quantities with the ores of zinc, and in still lesser quantities with the ores of lead and copper. Actually, the presence of cadmium in lead and copper ores is due solely to the presence in them of zinc compounds or minerals, in the absence of which, the ores would be cadmium free.

The ratio of cadmium to zinc varies greatly, and is often too small to be of any value whatever. The useful ratio varies roughly from 1 to 160 to 1 to 400, the latter ratio probably being nearer the average than the former. The production of cadmium except as a by-product is of course unprofitable, so its extraction is always associated with the metallurgy of the ore in which cadmium occurs.

Even though cadmium is obtained only as a by-product, the purity of commercial cadmium is extremely high, it usually containing less than 0.5% of foreign matter, and usually approaches 99.9% purity. The impurities usually found are traces of zinc, iron, lead, tin, copper, nickel, and very occasionally, traces of thallium.

The production of metallic cadmium has increased more than ten fold in the last ten years. In 1919, approximately 100,000 pounds of metallic cadmium were produced in the United States, while in 1927, 1,074,654 pounds of metallic cadmium were produced. Figures for 1928 have not been obtained, but undoubtedly exceed those of 1927.

The use of cadmium for electro-deposition has increased even more rapidly. In 1922, with a cadmium production of approximately 131,000 pounds, most of which was used in the manufacture of paints, chemicals, solders, etc., only a few hundred pounds were used for electroplating purposes. From that time on, the increase was rapid. In 1928, the Udylite Process Company alone used approximately 650,000 pounds. In the first four months of 1929 the Udylite Process Company actually sold and delivered to Udylite licensees 329,000 pounds of cadmium metal. This means that during 1929 one company alone will handle approximately 1,000,000 pounds of cadmium metal for electroplating purposes exclusively.

When it is considered that the average coating is only 0.0002” thick, the volume of work covered assumes staggering proportions. This amount of cadmium metal if spread on the earth’s surface to a thickness of 0.0002”, would cover an area of approximately 4 square miles, or 2,500 acres.

The color of cadmium metal itself is very often referred to as tin color, but it may be described as having a silver white color with a blueish tinge, and is more nearly the color of steel than of tin, which possesses a yellowish cast. Cadmium has a brilliant luster when freshly cut or polished, but becomes dull when exposed to the air. Cadmium crystallizes in hexagonal pyramids. The metal shows no cleavage, the fracture is brilliant and crystalline when pure, but fine grained and dull when impure. Pure cadmium sticks, when bent, give a sound very familiar to the so-called ”tin cry.” Impure cadmium sticks do not give this cry when bent, so in an emergency this test may be used as a rough test of purity.

Cadmium is soluble in most acids. Strong alkalies, such as caustic soda or caustic potash, which dissolve zinc very rapidly, have little or no action on cadmium. Cadmium combines directly with chlorine, bromine and iodine when placed in solutions of those elements. Cadmium is also soluble in ammonium nitrate.

Cadmium is harder than tin and softer than zinc. It is malleable and ductile at ordinary temperatures. Being soft, cadmium will not resist heavy mechanical wear, nor the action of abrasives. On the other hand, its softness and ductility make it more resistant than zinc or nickel to knocks or blows, just as a tough elastic enamel will outlast a brittle enamel.

The electro-deposition of cadmium has developed almost entirely in the last ten years. Acid and ammonicial solutions have been proposed at various times, but such solutions were found to be quite unstable, changing in composition quite rapidly, and producing a crystalline or porous deposit. This latter evil could only be partially remedied by the use of addition agents of various sorts. Cyanide solutions, even without addition agents, produce finely crystalline, though dull deposits, while various well known addition agents not only reduce the crystalline size still further, but impart a lustrous color very pleasing to the eye. Cyanide solutions are relatively stable as compared to acid or ammonicial solutions, requiring a minimum of care under severe conditions. As a consequence, cyanide solutions are mainly used for the electrodeposition of cadmium.

A metallic coating may protect the ferrous base either chemically or mechanically or both. Cadmium protects both chemically and mechanically. To protect the ferrous basic metal chemically, the coating metal must stand above iron in the electromotive series, so that in case the underlying metal is exposed, and moisture is present, which is almost invariably the case, the coating metal will function as anode in the little galvanic battery so formed, and corrode in preference to the basic metal. Some difficulty has been found in placing cadmium accurately relative to iron. Apparently, in the presence of moisture and corrosive substances, the easily changing iron potential and the over-voltage of hydrogen on iron, play a decided role. Regardless of the difficulty of definitely establishing the position of cadmium, practical experience has shown that cadmium undoubtedly stands above iron, and that it is now the best rust proofing agent, bar none.

Cadmium also protects mechanically. Even though cadmium is electronegative to iron, and porosity does not mean immediate rusting of the underlying iron, it is essential that the plate be as free as possible from porosity, in order that maximum benefit be derived from its properties. The ideal plate must also have perfect adherency, be free of blisters and irregularities, be ductile, dense and preferably bright in color. Cadmium deposits with such characteristics are obtained from most of the cadmium solutions in use today.

Efficient results in cadmium plating, as in other types of plating, depend essentially on three factors—the proper type of solution and means of controlling this solution’ proper electrical conditions, and proper handling of work. Under this latter may be included cleaning, pickling, rinsing before and after plating, handling, storage, etc.

The majority of solutions used today for the electrodeposition of cadmium produce deposits of finest crystalline structure and a minimum of porosity, as well as maintaining a constant composition under a maximum of varied operating conditions. Even with an ideal solution, work may often be spoiled by bad electrical connections. All leads should be of sufficient size to carry the necessary current, and all connections and contracts should be clean and tight. A source of trouble which is often overlooked are the contacts which the anode hooks make. All other connections are made by means of clamps or bolts. Here, however, contact is nearly always made by mere suspension, so that even under ideal conditions, there is possibility of electrical loss here. Corrosion products often form under the anode hooks, thus increasing the electrical losses still further. Even with proper leads and connections all the way from the generator to the solution, there is a final point often overlooked. Wires and racks for hanging work must be of a size to carry the necessary current. Obviously a part which requires 30 amperes for proper plating, should not be suspended on a wire with a carrying capacity of only 15-20 amperes. This, however, is often done.

Even after work has been hung in the plating bath, it may be spoiled by improper amperage, or current distribution. In the matter of current distribution, best results are naturally obtained with only one piece in the tank at a time. In production, however, the tank must be loaded, and often loaded with pieces of varied size. Current is free to pass through various channels, and the amount that does pass through a given piece is a function of the size of the piece; contacts to anode and cathode, size of racks or wires; distance away from anode; the solution itself, and finally the voltage impressed. Each time the tank is loaded, the chief variables are the number, size and shape of the pieces, and the contacts. The operator should see to it that each piece is gassing as evenly as possible, that the contacts do not become hot, and that the plate is as evenly deposited as possible. Sharp edges always receive the most current, consequently they will brighten first. If the edges are dark, the work is burned, which indicates too much current. It is best to strike a happy medium between high and low current density.

Poor cleaning is responsible for a multitude of plating ills. It is readily recognized and accepted, but it is very difficult to remedy in many cases. Since the cleaning problem is usually an individual problem, and so many excellent articles have been written on cleaning and pickling, which later may be considered a branch of cleaning, that I will not go deeply into this subject. I will merely state, that even though it is sometimes possible to obtain a good cadmium deposit on dirty looking work, consistently efficient results can only be obtained by perfect cleanliness at every step in the plating department.

After the work has been cadmium plated, it should be immediately rinsed” in cold water and then in hot water at approximately boiling temperature. The water should be clean to prevent staining. Where facilities permit, small parts may be dried in a centrifugal, which eliminates water staining.

The plated work should be removed as soon as possible from the acid fumes and steam atmosphere of the plating room; it should be stored in clean boxes, handled by clean hands and placed upon clean work benches.

In this paper, I have endeavored to show very briefly the necessity for such a metal as cadmium, its origin, its development and rise to a most commanding position in the electro-plating world, and finally a brief and general discussion of the best plating room practice to insure successful cadmium plating.


A REPORT OF THE POSSIBILITIES OF POISONING FROM CADMIUM PLATE

Read at Detroit 1929 Meeting

by George Dubpernell

The question of the possibilities of poisoning from cadmium plate frequently comes up, but the published information on this subject is very scarce. The possibilities are often vastly overestimated, there being no definite evidence available to the contrary. Under these circumstances it would appear advisable to discuss the possibilities in detail, in order to define them.

There appear to be no cases on record of persons having died from cadmium poisoning due to cadmium plate or cadmium salts. An authoritative text book on ”Toxicology” states that, ”So far as one may find, no deaths have been reported from employment of cadmium salts and in man the acute effects are those of a gastrointestinal irritant.”

A British engineer is said (Chemical Trade Journal, Volume 75, pages 3 to 5, 1924) to have died from the effects of cadmium vapor which he inhaled when some cadmium was melted and overheated in an open crucible, instead of in the regular furnace, which was out of order at the time, There is no danger of this kind in the use of cadmium plated products, as the quantity of cadmium on them is so small.

Only one article appears to have been published on the use of cadmium as a coating metal for food containers, and that is German (Zeit, fur Unters. der Lebensmittol, Volume 54, pages 392-6, May, 1927). Lead and zinc are prohibited in contact with foods in Germany, and this article is mainly a plea for the inclusion of cadmium in the lead-zinc law.

Here in the United States, the Bureau of Animal Industry of the Department of Agriculture has prohibited the use of both zinc and cadmium in direct contact with meat or meat food products for considerable periods of time. This does not mean the complete prohibition of cadmium or zinc plating in the packing houses, however, and it is of course permissible to protect various parts of mechanical equipment, etc., from rusting in this manner, as long as they do not come into direct contact with meat or meat food products for a long time.

Cadmium salts are not accurately described as poisons to the human system from the ordinary person’s point of view. In some cases they have been prescribed by physicians for use as an emetic. The government chemists have shown that cadmium salts are 8 to 9 times as effective as zinc salts when used as an emetic. The same men, and also many other workers, have found no cumulative effects of cadmium salts when fed to animals for long periods of time. (Journal of Pharm. and Exp. Therap., Volume 21, pages 1-22, 59-64, 1923, and Journal Pharmacol. Proc., Volume 13, pages 504-5, 1919.) That is quite different from the case of lead salts. If you get just a trace of lead, it continually stays in your system and eventually it becomes badly poisoned by it, if you keep on getting a small quantity of lead.

The effect of cadmium salts when taken internally is to cause severe vomiting, diarrhea, nausea, headaches, etc., and temporary local injury to certain organs. The most severe case on record was described by G. A. Wheeler in Boston Med. & Surg. J., Vol. 95, P. 434-6, 1876, in which several women took from .25 to 1 grams of cadmium bromide, each, accidentally; both were made violently ill; one recovered in about 24 hours and the other in about 5 days.

Cadmium salts have valuable antiseptic and bactericidal properties and have been recommended for various therapeutic uses.

Cadmium is only very slightly soluble in neutral or alkaline solutions, and in solutions of organic substances in general. It is, however, slightly soluble in weakly acid solutions, which sometimes occur in connection with foodstuffs. Zinc, on the contrary, is soluble in both acid and alkaline media and generally at a greater rate owing to its higher solution pressure. The difference between zinc and cadmium salts considered as poisons is one of degree only, the cadmium salts being stronger in their action.

Cadmium metal is fairly rapidly attacked by any foodstuffs of an acid character, such as vinegar, hard cider, fruit acids, etc. Fresh meat, blood, milk, etc., have practically no action upon metallic cadmium when they are fresh and edible, because they are slightly alkaline in reaction. However, when these protein containing foodstuffs decompose or turn sour, they generate acids or amino compounds which may have an action on cadmium, and when the cadmium is then dissolved, it causes sickness for a few hours or a day if sufficient quantities are ingested into the human system. We have actually encountered at least several such cases of sickness caused by cadmium getting into foodstuffs; the results in these cases were rather unpleasant, and painful internal disturbances, frequent vomiting, etc., occurred.

The situation can probably be summarized as follows: Cadmium in its dissolved state is a powerful emetic and its general use in contact with foods is to be avoided. It is only possible to use it in specific cases where the conditions are definitely known and do not vary, where the foodstuffs in question is neutral or alkaline in reaction, and will not turn acid.

Acid food products such as vinegar, lemon juice, and other fruit juices, sour milk, etc., may attack cadmium plate quite readily and cause illness to persons who eat the foodstuffs.

CHAIRMAN VAN DERAU: Have any of you any questions to ask of Mr. Dubpernell?

MR. JOHN E. STERLING: I would like to ask Mr. Dubpernell a question. In the event of knives cutting into salt meat, and so forth, you think the cadmium plate would be affected?

MR. DUBPERNELL: No, I certainly don’t. That was where this question first came up, in the packing houses. I have here some shroud pins that were tested for use. (Shows pins.) These had been immersed in fresh meat over night while it was cooled. You see, they kill the animal and then pin a shroud on it with these pins. They are put in the meat when the meat is warm and fresh, and then the meat is cooled in the refrigerator over night. These were immersed eight times, eight over night periods, and the cadmium is still on them. If you were going to get any injurious action, the cadmium certainly would have been taken off in that length of time. Experience has shown that they can use these shroud pins, put them in meat over night for—I don’t know, they don’t know themselves, but they have told me as much as one hundred times before the cadmium is appreciably attacked. Possibly at the end of that time it has been worn off by pushing in and pulling out.

MR. STERLING: How would that apply to salt and pickled or brined meats?

MR. DUBPERNELL: I imagine it would be all right in that case, too. But you have to be careful; you can’t go too far. Fresh products are all right. It is something salty and neutral or alkaline in reaction. But the minute you get anything that may turn acid, for example, if you don’t wash these things off and leave particles of meat on them, as the meat decomposes it will corrode the cadmium. If you keep using it in fresh products it is perfectly all right.


A. E. S. PAGE
Assembled Expert Scraps With and Without Significance

It looks like our capitol has at last gone dry.

Did you notice R. J. Hazucha and J. Oberender doing a lot of taxi riding Sunday evening? Rudy says there was no beer and John agrees.

The Platers looked so tarnaly sober many were taken for Senators in the corridors of the hotel.

H. Flanagan sure forgot his knickers, and we missed his good wife. Also Mrs. Tom Haddow, even if Tom don’t play with knickers.

A. P. Munning, Capt. Taylor, Van Winkle Todd, Archie MacDermid and Sam Huenerfauth were there. Did you see them spreading the stuff that makes good around the lobby.

Our good friend, Dr. De Baun, was there as usual and we’re glad he was.

Balti.-Wash. Branch members did themselves proud and we all thank them.

Dr. Blum sure did not get much sleep during the annual meeting and his good wife gave freely of her good offices.

Our past editor sure ought to be able to watch around now after that wonderful testimonial of friendship.

Horace, Phil and Oliver, three must get theres. ”Yes.”

Did you notice those Slattery’s, John, Tom and the missus, all busy?

Oh boy! Did you notice the way the gang ate those box lunches at the Navy Yard?

Some thought that visit to the Tomb of the Unknown Soldier and depositing our respects in form of wreath by Boy Scout R. Mesle. Offices also.

Did you see Ed Musick and Geo. Laurence at the desk? Horses. Yea.

Where was E. Lamoureux H. H. Williams and Ed Willmore?





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