The Iron Age 1941-07-03: Vol 148 Iss 1

j The New Departure Shop Manual should read every man responsible for the correct in- stallation ball bearings for maximum service and long life. Send for your copy and tell how many additional copies would required supply your interested personnel. New Departure, Bristol, Con- necticut. Defense Building While New Departure’s vast productive facilities are giving defense projects right way, New Departure’s technical staff has not forgotten its duty its regular customers and their defense problems. fact, both old and new users New Departure Ball Bearings will find extremely helpful this latest the New Departure Engineering the Shop Manual. NEW DEPARTURE THE FORGED STEEL BEARING : | 4 ie Rha VG | Editorial Technical Articles Screw Machine Tooling for Munitions Parts Electroplaters Discuss Year’s Developments Mass Shell Production New Welding Apparatus Features Fatigue News and Market Reports News Industry Machine Tool Activity Personals 114 Non-Ferrous Market JULY 1941 115 Scrap Market Meal-Working Activity Fabricated Steel VOL. Comparison Prices 118 OL. 148, NO. Summary the Week 119 Iron and Steel Prices The Industria! Pace 120 Warehouse Prices District Market Reports 122 Sales Possibilities President and Editor BAUR Vice-President and General Manager Information Products Advertised C. E. WRIGHT J. A. ROWAN T. W. LIPPERT * Index Advertisers Managing Editor Editor Machine Tool Associate Associate Editor Editor Copyright, 1941, Chilton Company Associate Editor Associate Editor WINTERS Art Editor Washington Editors L. W. MOFFETT JAMES G. ELLIS DIX, Manager Reader Service Owned and Published (Incorporated) Resident District Editors Advertising Staff Executive Editorial and CAMPBELL HERMAN KLEIN Emerson 621 Union Bldg., Cleveland Office Advertising Offices Chicago Robert Blair Chestnut and Séth Sts. 100 East 42nd Herman, Chilton Bldg., Philadelphia Philadelphia, Pa. New York, Cleveland Detroit Leonard, East 42nd St., New York Peirce Lewis, 7310 Woodward Ave., Detroit Editorial Correspondents DEARING ROBERT McINTOSH Buffalo Cincinnat FRAZAR CHARLES POST Boston San Francisco HUGH SHARP JOHN McCUNE Milwaukee SANDERSON ROY EDMONDS Toronto, Ontario St. Louis LEROY ALLISON Newark, Ober, 100 East 42nd St., New York Don Harner, 1595 Pacific Avenue, Long Beach, Cal. Member, Audit Bureau Circulations Member, Associated Business Papers Indexed the Industrial Arts Index. Pub- lished every Thursday. Subscription Price: United States and Possessions, Mexico, Cuba Canada, $8.50; Foreign, year. Single copy, cents OFFICERS AND DIRECTORS MUSSELMAN, President JOS. HILDRETH, Vice-President GEORGE GRIFFITHS, Vice-President EVERIT TERHUNE, Vice-President VAN DEVENTER, Vice-President BAUR, Vice-President WILLIAM BARBER, Treasurer JOHN BLAIR MOFFETT, Secretary JULIAN CHASE, THOMAS KANE, HARRY DUFFY CHARLES HEALE 7 q | | be \ P ) ) nit: wcnin el | : + rd Vaeation this Year? Though our national emergency shortening and even can- celling many vacations this year, hope able slip away for few days least. While gone, your department can rely Ryerson for the best steel-service that present-day circumstances will permit. times like these, are naturally out many sizes but still have fair stock and service continues without interruption. make the best your days Relax! Build yourself for the hard winter months ahead. Ryerson will help hold the fort. Jos. Ryerson Son, Inc. Chicago, Milwaukee, St. Louis, Cincinnati, Detroit, Cleveland, Buffalo, Boston, Philadelphia, Jersey City Shortages and Capacity steel industry will make serious mistake permits the brain trusters and business stampede into building mil- lion tons additional ingot capacity. Here and there, course, there will have additions made be- cause the abnormal emphasis which war and defense place upon cer- tain specialized products. Electric furnace steels are case point. But here have need adjusting total capacity rather than increasing it. And when comes the matter adjustments, the one that most seriously needed that apportionment supply. long have per cent our present steel making capacity available for non- defense business, the chief reason for any one’s not getting the steel needs make the products that his customers need the maladjustment demand capacity. This sounds rather involved, but really isn't. can simplify imagining that steel flour. One would say that nation had ample flour milling capacity its mills were capable grinding enough wheat make enough bread feed all its people. Under such circumstances, any shortages that would develop would due demand being out adjustment needs and not due any lack capacity. JULY 1941 Suppose, for example, that impending flour shortage was rumored. Suppose that Government economists advertised from the housetops Washington. What you think would happen? ESTABLISHED 1855 Instead buying her customary one bag flour, your wife would buy two three bags. She would try protect the interests the family pantry stocking up. And would millions other women. Now even were the capacity the flour mills the country half again much need be, all these women merely bought one extra bag, immediate shortage would develop which would equivalent three months’ operation the flour mills. would temporary shortage, course, and would work itself out time unless the was repeated. But during that period the shelves the grocery stores would bare flour. Under such circumstances, would silly suggest increasing the flour milling capacity. For the time that was accomplished, the need for would over. That exactly the situation today respect steel. you are not getting the steel you need, not because that small per cent our annual output that going into defense and aid Britain. because some one else getting more than needs the remaining per cent. And you cannot cure that general expansion program that will take two years get going. f al + 4 |_| | |_| q | 2 \ ; f 7 | 7 Offices: Milwaukee, Detroit, St. Paul, St. Louis, South Dearborn Street, Chicago, ~ J > P : i 4 FRANK OLIVER Machine Tool Editor, The lron Age special tooling arrangements, illustrated detail, have been worked engineers the Acme Co., Cleveland, for three typical ammunition components—the M-20 booster, the 37-mm. high explosive shell and machine gun bullet cores. The tooling for the booster body particularly ingenious, while the decision machine the tungsten-chrome bullet cores eight spindle machine represents the culmination much preliminary work and many experimental tries accomplish the result other types automatics, from one spindle, up. The H-E shell typical second operation set-up. UTOMATIC are being called carry the bulk the produc- tion small size shell and bullet cores and fuse parts for bigger shells because the economics tooling for large quantity pro- duction. Such parts lend themselves ready production from bar wire stock. fact, the choice not between doing this work automatics but selecting the ma- chine the necessary number spindles and tooling perform many operations possible one set-up; the case the tougher materials, subdivide the opera- tions maintain economical tool life and relatively high produc- tion. For the purpose ing some the principles tool- ing involved, have selected three typical munitions parts, Fig. all which run into large quantities and which large number in- dustrial plants have been called upon make. Some the tooling was developed for government ar- senals, but has been duplicated outside contractors. Because its unusual design, the M-20 booster, one the con- necting links between the timing mechanism the nose shell and high explosive charge, presents problem cailing for considerable ingenuity its solution. This piece, shown the right Fig. made from haif hard, common brass the form 2-in. bar stock. Except for drilling and tapping some small bore holes, the piece completed one setup eight spindle, in. model automatic bar machine. The machining cycle in- cludes two external threading oper- ations, one internal threading oper- ation, boring eccentric hole the base the main bore, and slotting the open end, all per- formed without stopping the rota- tion the work spindles. Gross production 276 pieces per hour. Fig. illustrates the tooling layout. First operation the M-20 in. hole the end the bar while the body rough formed over half its length and the outer end cham- fered. This done position No. the lower rear spindle this machine where the stock fed out. Forming done circular tool carried the lower rear cross slide. Work spindle rotates 728 (121 ft. per min. in. maximum diameter) and the feed the tool slide, which carries the drill, 0.0088 in. per rev., with total feed in. Second operation station finish form the rear contour the piece, turn the front thread di- ameter with knee turner the THE IRON AGE, July 1941—33 \ ° ° a 4 Face Dril/ eccentric hole Tap Cut t thread Cut off way 2—Sequence operations for producing the M-20 booster eight-spindle automatic bar machine. 34—THE IRON AGE, July octagon tool slide, and square bot- tom and chamfer the previously drilled hole front. this sta- tion, the form tool tangent with dovetail back, carried the lower front cross slide. the third operation, the end the piece faced length with knee turner the end tool slide and the same time No. drill (0.201 in.) driven auxiliary air drill spindle used drill the small hole the center the body. Because the rela- tive speed work and drill, the actual feed becomes 0.0035 in. per rev. for this drilling operation. Eccentric Drilling Operation The fourth operation, station one the most interesting the piece. This drilling ec- centric hole the base the bore. some types automatics such operation might performed driving the spindles through friction disks that the spindles suitable brake while auxiliary spindle the tool slide performed the drilling operation off center. much power required other operations, however, that National- Aeme has chosen instead form this operation without stop- ping the work This done through the use special drilling rig, illustrated cross-section Fig. special flat bit used, carried ball bearing mounted quill which the same axis with and rotates the same speed the work spindle this position. Within this quill the drill holder proper mounted eccentrically, needle bearings, amount corresponding the off- center position the hole being drilled. Constraint the drill against rotation the same speed the quill obtained gear, integral with the drill spindle. This gear engages fixed internal gear concentric with the main quill and bolted the housing the drill- ing unit. The ratio teeth 28:33 difference five teeth that the drill has absolute speed speed 110 r.p.m., the reverse Relative the work, which rotating 728 r.p.m. for- ward, the drill speed therefore 838 r.p.m. watch this operation, however, one would get the impres- sion that the drill was slowly rotat- ing about its own axis while de- scribing gyratory path circle about 5/16 in. diameter. modi- fied tooth form had developed for this pair internal and ex- ternal gears, which are cut Fellows gear shaper with special circular cutter. station two threading oper- ations are combined, one internal threading, the other external threading the smaller threaded diameter. This outside thread produced small double thread roll mounted special fixture carried the top front side tool slide. This thread roll given straight infeed the lead angle and free rotate its own axis, being driven friction the work itself. The diameter the blank which was finish formed the second operation slightly under the pitch diameter the fin- ished size. the design this double thread roll, necessary make the pitch di- ameter factor the pitch diam- eter the thread being cut and the number starts the thread rolls must factor the num- ber threads per inch the screw being cut; that is, th. screw, for example, may cut with roll becomes almost impossible make this thread roll lathe having standard lead screw and the usual change gears. The internal thread cut with standard 17, in. type Namco collapsible tap mounted thread- ing attachment the main end tool slide and driven off the fifth station flat form tool the side slide begins the cut- ting-off operation which done three steps; otherwise, this would the longest operation the piece. now, the initial drill- ing operation station the con- trolling one from the point view production time, which sec. per piece, machine time. the fifth station, threading also per- formed the larger the two external threads, using standard in. type Namco self-open- ing die head with ground thread circular chasers and another threading attachment driven off jackshaft. Slotting Attachment station cut-off continued with flat form tool held independent side slide, and the open end the booster body slotted with special attachment the end tool slide, detailed Counterbore Finish small hole Thread eccentric drilling operation, this slotting performed the body while rotating and the slotter tools are the end auxiliary spindle driven off the main drive shaft the same speed the work spindle. The two tool bits oscillate back and forth with each spindle revolution, and being fishtail shape they cut each direction. Reciprocation the dovetail slide which the tools are opposed roller contacts engaging hardened raceway which eccen- tric the spindle axis. eccen- tricity about in. gives total tool reciprocation in. Final cut-off takes place the seventh and last station. Since side slide employed for position this tool mounted double- decker fashion top the form tool holder the rear side slide recalled the initial forming opera- tion the booster body formed. Second Operation Work Another for study the second operation set-up for finishing the body mm. M-54 high explosive il- lustrates how even magazine chucking set-up can made fully automatic. When reaches this machine, which in. model Acme-Gridley, this piece 1.453 in. diameter and 4.13 in. long. made modified SAE X1335 cold drawn steel. has al- ready been turned the o.d., bored one end and banded. shown the tooling layout, Fig. the piece automatically checked set special from maga- zine feed. Ejection the finished piece and loading both take place station Turning the copper band done two steps stations and respectively carbide tipped Pitch IG. typi- cal munitions parts pro- duced automatic screw machines. mm. high explosive shell. (Right) M-20 booster. 0.50 caliber machine gun bullet core. tools mounted knee turners the end tool slide which has feed 0.0039 in. per rev. (288 r.p.m.) and total feed only in. which why this particular case the facing cut the band cannot made one step. Also station closed end the shell body, which hole then progressively drilled 31/64 in. diameter the next three stations, and sta- tion dovetail type form tool mounted double-decker tool post the front cross slide forms the groove ends the band and puts groove the steel body front the band. This form tool against the steel land the shell. the same time facing tool the end tool slide comes with the drill face the end. station drilling continued final depth with specially ground step drill and chamfering IG. 3—Cross-section spe- cial drilling head mounted the octagon tool slide for drill- ing eccentric hole the base the main bore the M-20 booster. ‘ tool bevels the edge the hole. Stenciling the band done station well flat bottoming the small bore with specially ground drill. Stencil roll moved tangentially the piece that back roller support can the same time. The same principle also applied for the movement the form tool station Accelerated reaming 31/64 in. hole in. per- formed station with the aid attachment and the same time the end support finish faced. drill 0.209 in. hole through the main cavity. This done with standard high speed drilling at- tachment mounted the end tool slide, and mechanically driven off the machine jackshaft. another machine this hole tapped in.-28 threads. Machine time gross production 156 pieces per hr. Tu:ning Bullet Cores Turning extremely tough mate- rial like SAE chrome steel for 0.50 caliber ma- POSITION THE IRON AGE, July 1941—35 Feed from chuck band partway, Spot LEFT IG. 5—Sequence second op- eration work mm. M-54 high explosive shell eight spindle automatic. band remainder Drill hole BELOW sequence for production 0.50 caliber tung- sten chrome bullet cores from 29/64 in. round ground When the stock fed out sta- tion the nose has already been rough formed during the process cutting off the preceding piece. : Rough form turn point form and boat support groove and ends Firish pornt Shave body and boat for cut off Pick and face end 36—THE IRON AGE, July 194! IG. 4—Cross- section spe- cial slotting at- tachment used sixth position for slotting end M-20 booster body while con- tinues rotate. chine bullet cores necessitates breaking down the operations into number stages order ob- tain economical tool life. Attempts have been made turn these bul- let cores single spindle machines and also turn the cores three stations, double tooled six spindle bar turning machine. Neither were satisfactory because each was called upon too much work. National Acme believes the final answer the set-up shown the tool layout, Fig. for six-spindle bar machine, with station tooled separately, giv- ing gross output 554 pieces per hour, 6.5 sec. per piece. addi- tion. the final cut-off arranged such manner that second oper- not required face the nib off the boattail the core. For the 0.50 caliber core, the ma- terial the form ground stock in. diameter. Spindle speed 611 r.p.m., giving cut- ting speed ft. per min. the maximum diameter. High speed steel tools are used throughout. Provision made every station for quick set-up tools means simple swing-type gages perma- nently attached the tool posts. Cycle begins station No. when already rough formed the nose, fed forward against stop button. fact, dur- piece, the nose the succeeding piece broken down four steps. For instance this station, form 8 € ‘= { bottom hole = layout for producing 0.50 caliber machine six spindle National Acme bar machine. — 3232 POSITION POS/TION THE IRON AGE, July 1941 0 ji — Rie > “4 Sap "Wes / Ax, ‘ Ss ' rt Standard back he VL 38—THE IRON AGE, July 1941 ‘ tool the lower rear cross slide fed straight rough form the boattail and start breakdown the nose the following piece. This tool, cutting the work cen- terline, set through the aid simple U-shaped gage which brought bear against the tool- holder assembly. Initial adjustment the gage obtained setscrew and locknut. This can seen the detail, Fig. lower right. Turning the core point done this station modified roller turner, the roller being mounted angle the work axis and the direction tool feed. Tool slide feed in. Final finish forming the point done station No. with box turner and profile tool, really shaving operation since only few thousandths stock removed. Before this done, however, sta- tion No. the body formed necked just the rear the bourrelet and the boattail support partially necked down. this station, the rough formed nose supported ball bearing live cen- ter. Since the form tool in. width and not backed roller because the amount stock being removed, this female center heavy mandrel with generous size ball bearing carrying the overhung load the inboard end. Since necessary for this center point engage the core the start the cut, timed with the start the tool slide feed, the cen- ter mandrel proper backed heavy spring and has in. movement within its supporting sleeve. station setting the dove- tail backed form tool, which mounted the front cross slide, facilitated simple pivoted flat bar which can swung over the tool slide act stop for the tool the work centerline. This centerline necessarily must corre- spond with the top face the tool block which the stop bar piv- oted. The same type tool setting gage employed stations Nos. and except that the last named station because the pe- culiar shape the tool holder the tool contact button the end stud instead the flat bar itself. station No. the core body and boattail support are shaved with heavy dovetai! shaving tool the roller rest type, fed from the upper left cross slide much like snap gage would slipped over Rear view the bar ma- chine tooled for bullet cores. Stations and and the pick-up attach- ment may seen. the work diameter. Tip the core supported ball bearing sup- port station No. except that since the greater part the tool reaction, namely the normal com- ponent, taken the roller, the live center smaller diameter and supported lighter bear- ings. This live center carried similarly the main tool slide and has spring take-up during the feed part the cycle. station No. further break- down the nose the following piece carried preparatory cut-off the next station. Since the tool working close the col- let chucks, not necessary support the work live center ous station. dovetail backed form tool used, being mounted tool block carried the upper right cross slide. the fifth and last position, the work picked and cut off such manner that the tool car- ried past the work center, removing the nib entirely and facing the end that additional operation necessary except solder rein- forcing disk absorb some the impact the propellant charge. Cut-off accomplished form tool which also shapes the nose the following piece, this tool being cross slide actuated two-step cut-off cam, giving 5/64 in. feed 0.0023 in. feed rate and 1/32 in. 0.0015 in. The second step the feed carries the cut-off point past the work center, giving the effect what would normally second operation the tail end the core. What makes this operation pos- sible special rotating pick-up attachment, shown cross-section Fig. This unit looks compli- cated and costly build, but pays its way eliminating the second operation. The attachment gib- bed the main tool slide V-ways and reciprocated independently the latter. Essentially you find this unit means rotating collet chuck step with the work spindle speed 611 r.p.m., means for drawing the collet tight after slipped over completed core prior cut-off, and means for feeding the cores out through hollow spin- dle the attachment. for this last named reason that power for drive carried and around through series spur gears and jackshaft instead driving straight through. Each time the stock advanced, finished core pushed one length along the col- let tube, dropping off the far end into work trough. Main advance the attachment toward the work rocker arm and link. Collet closing effected secondary travel in. the auxiliary member will noted that this collet the stationary fin- ger type with the cone the moving member. The cone pushed for- ward the aforementioned stock discharge tube when the two fin- gers are cammed toward the cen- ter. Main quill carried needle bearings and the facing thrust taken ball thrust plate bear- ing. Jackshaft carried bronze sleeve bearings because space limitations. THE IRON AGE, July ale his in. lat the the his re- ool ast pe- the elf. ved ike ver chemical Methods for the Purification Plating So- lutions,” was the title paper Stocker, Rufert Chemical Division the Seymour Mfg. Seymour, Conn., which pointed out that large part our present plating difficulties can traced impurities one sort another, metallic compounds or- ganics. They ean identified the analysis the metallics the bent cathode the Hull cell test for organics. The bent cathode shows dark area the right angle bend. The Hull cell shows im- purities over the whole range, from low current density 140 amp. per sq.ft. the characteristics the test panel deposit. Precipitation and filtration are satisfactory for heavy acid and alkaline baths, and for car- bonates cyanide solutions. also satisfactory raise the low baths precipitate out im- purities. Change the constitution im- purities recommended for organ- ics (by severe oxidation and reduc- tion) destroy the compounds, and then filtration through acti- vated carbon eliminate the bal- ance impurities. Co-deposition impurities ap- plicable both metallic and organ- impurities low current densi- ties dummy cathodes. Such electro-deposition involves control 40—THE IRON AGE, July week's report the annual convention held Boston here continued with papers solutions, their purity and acidity, radiant heat baking, equip- ment, electropolishing color. the and temperature, proper agitation, the ratio the impur- ities the metal normally de- posited, the cathode reaction and position the metal the electro- motive series. nickel solutions, impurities may consist copper, lead, cad- mium, iron, zinc, selenium, alumi- num, chromium, magnesium, cal- cium, carbon dioxide and dissolved oxygen. Organic impurities may come from buffing compounds and faulty tank lining. Raising the 6.2-6.4 electrometric the addi- tion nickel hydroxide, nickel car- bonate, calcium hydroxide, hydro- gen peroxide potassium bichro- mate, removes zinc, trivalent chromium, selenium, cadmium, bi- valent copper. Additions are made wet slurry the chemical hot water and added the solution gradually, with vigorous stirring. typical procedure heat the bath 140 deg. F., and then add nickel carbonate wet slurry, slowly, with stirring until the 5.6-5.8. This should take about per 100 gal. solution. Then add slurry lime the same fashion until the about 6.2. This should take about per 100 gal. Then add pint 100 vol- ume hydrogen peroxide per 100 gal. solution; stir and filter. The Liscomb method removing impurities add oz. fer- rous sulfate per 100 gal. solu- tion, raise the temperature 140 160 deg. F.; add nickel carbonate then add oz. per gal. 100 vol- ume agitate for two three hours and filter. Impurities, such copper, lead and selenium, can also removed “cemented” out adding pure iron nickel the solution, then re-purified chemically remove the dissolved iron. Removing Organic Impurities quires larger amounts hydrogen peroxide and also chromate than for inorganic com- pounds. Care must used when purifying bright nickel solutions not destroy the necessary organ- ics the bath. One method heat the solution 140 deg. F., add oz. activated carbon per gal., then qts. 100 volume hy- drogen peroxide per 100 gal. so- lution, all with constant agitation. Raise the the solution about 6.0 with nickel carbonate ‘ “a ° ° ° ° | nickel hydrate. The time taken for such purification generally from hours, but proceeds fas- ter higher temperatures. For plating out impurities low densities not over amp. per sq. ft. are required, using auxiliary tank with large anodes and dummy cathodes. Agitate the solution. This method will also re- move some organics. The copper cyanide solution amenable such purification treat- ment, which lead, thallium, cad- mium, silver, zinc, nickel and tin removed. Carbonates can precipitated with calcium sulphate. barium chloride, barium cyanide freezing, desired. The rec- ommended method calcium sul- fate the rate about per 100 gal. solution, which will re- move sodium carbonate the rate oz. per gal. The author also described the purification other solutions such acid copper, brass, cadmium, anide zine, acid zine and silver. Value Cyanide Baths Gray, Electroplating Divi- Co., Cleveland, outlined the mea- suremer significance and control claimec that the study plating baths, including various cadmium, copper, zine and brass solutions, has shown the im- portance controlling this factor since has marked effect the operating characteristics the baths and the quality the deposit produced. new, high alkaline glass electrode was found en- tirely satisfactory for measure- ments cyanide solutions, and represents the first practical and accurate method for measurements cyanide plating baths. The electrode almost neg- ligibly affected sodium ions high pH. The type electrode has been developed for ranges and 13. Comparisons show good agree- ment between the hydrogen elec- trode and the high alkaline glass electrode—within plus minus 0.1 unit. The high alkaline type glass electrode stable alkaline solutions. useful the con- trol alkaline baths and titrations determine caustic content. Albert Snyder, Philadelphia, presented paper called and objections the salt spray test from troplating point view,” the prac- tical plater’s attitude, particularly applied production work the manufacture automobile parts, hardware, etc. The advantage the salt spray test its usefulness compara- tor, its ability expose defective plate and distinguish between thick and thin deposits. For ex- ample, the salt spray showed hot dipped cadmium-zine plate which lasted only hr. against elec- troplated cadmium which lasted 100 hr. spray lies its poor correlation with exposure tests and life ser- vice. The methods applying the salt spray are not standardized and the results the test vary with the position the specimen the box, with the concentration so- dium chloride, with the method inspection and rating. The test easily subject misinterpretation laymen and seems impos- sible get quantitative unit for the measurement corrosion. The author thought that would best omit the salt spray test from specifications because its unre- liability and rest outdoor cor- rosion tests, the same time keep- ing the plated articles service clean. Rubber Lined Tanks Rubber lined equipment for the plating room was described McHugh, Manhattan Rubber Divi- sion Raybestos-Manhattan, Inc., Passaic, Because the fact that chemically inert, rubber ideal material for plating tank linings and accessory equipment. Rubber tank linings are several types: soft, semi-hard and combi- nations (in layers, double, triple and the hard-and-soft wich” type). Rubber lining may also sprayed on. The best hard rubber, compounded retain some its flexibility.and bonded directly the tank. The author described the manu- facture compounded rubber sheet for tank linings, the method ap- plication and bonding tanks hand work, testing the tank the electric spark, and vuleanization curing the rubber. Rubber tank linings are suitable tor all plating solutions and all in- organic acids except the strongly oxidizing, such nitric, chromic, sulphuric and over per cent. They are suitable for all alkalies and inorganic salts and many organic acids. Some the difficulties encoun- tered with rubber tank linings may (1) Contamination accelerators and anti-oxidants which may used the rubber, but which should not present, least such form free them- selves from the rubber. (2) Softening other attack wetting agents, anti-pits, bright- eners, etc. Before using any such addition agents, advisable submit sample the manufac- turer the rubber lined tank used, for his approval. (3) Plating out the tank lin- ings; rare but when does happen, due defective installation, such insufficient curing, etc. “Removal Chromium Contami- nation from Alkaline Plating Solu- was paper presented Co., Wyandotte, Mich., which said that one the objectionable impurities copper cyanide solu- tion the chromium the hexa- valent state sodium chromate. present the proportion 0.075 grams per liter, will reduce the cathode efficiency less than per and also cause blistering copper deposited from the copper strike, dulling the sub- sequent bright nickel plate, streak- iness, poor adherence, etc. The objectionable chromium may removed with sodium hydrosul- The following equa- tion shows the reaction this ma- terial changing chromium from the hexavalent the trivalent: The trivalent chromium hy- droxide appears precipitate Rochelle salts are present and may filtered. the presence Rochelle salts, the trivalent chro- mium mixed with the tartrate complex and will not injurious long remains the tri- valent state. Sodium hydrosulphite also sat- isfactory for removing chromium from cyanide zine and cadmium lutions. Radiant Heat Baking One the outstanding presen- tations the meeting was paper Gustav Klinkenstein, Maas Waldstein Co., Newark, J., “The Uses and Limitations Radi- ant Heat Baking Organic Fin- THE IRON AGE, July e Ss = 1 r ja ishes.” appears that infra-red baking was first applied commer- cially the plant the Ford Mo- tor Co., Detroit, about 1933. This company controls the patents the process, but permits their use throughout the industry with- out restrictions. Infra-red heat applied elec- tric lamps generally arranged tunnel through which the prod- other cases portable bank lamps used and also individual lamps. The rays produced are “near infra-red” them from the “far infra-red” rays used convection ovens. The lamps are equipped with reflectors con- centrate the radiation the work. Under these rays, the finish film comes the baking tempera- Visible light rays from violet red, have wave length from 4000 7800 Angstrom units. The far infra-red rays may have wave- lengths 120,000 Angstrom units. The near infra-red which used for baking organic finishes, has wave-length from 7800 14,000 Angstrom units. addi- tion, certain types lamps with enclosed reflectors use band rang- ing from 7500 30,000 Angstrom units. has been considered the past that radiant heat has effect the finish and the air which passes through its beams, but only the metal which heated. This concep- tion incorrect. Infra-red heating generally used for opaque fin- ishes which are not penetrable radiant heat. Radiant heat sim- ply new and very rapid method applying heat and suitable for certain classes work, but unfitted for others. should compared with convection ovens for specific jobs make choice, but will not completely supersede the oven. The best conditions for radiant heat baking include: (1) Low cost current. (2) Heating equipment especial- designed for the special product. (3) Reduction heat losses: (a) Radiation must strike the work; (b) must not reflected from the work; and (c) must not re-radiated high tempera; tures. Also, heat must not car- ried away convection. (4) Baking temperature should not exceed 600 deg. (5) Quantity production 42—THE IRON AGE, July quired for products similar size, shape and finish. Only those finishes which are hardenable short time heat alone can used. Oxidation hard- ening finishes, such japans, are not suitable for radiant heat. Clear finishes polished surfaces are unsuitable. Clear finishes non- reflective surfaces are satisfactory. Certain finishes may char burn yellow and certain enamels may wrinkle get fatty edges con- vection ovens, but perform satis- factorily under radiant heat. Fin- ishes should specially formulated for this type heating. The advantages radiant heat baking are summarized thus: (1) long preliminary heat- ing period required. Gen- erally, min. will sufficient for the baking job. (2) suitable for conveyor operation. (3) The baking equipment simple, light and flexible and can installed any point the con- veyor line. can also set and removed will, wherever sufficient length travel available. (4) Space requirements are from 1/3 1/10 convection ovens similar capacity. (5) The installation cost low. (6) The maintenance cost low. Lamps last 5000 10,000 hours. Reflectors can kept good con- dition cleaning once month. (7) The fire explosion hazard very low. (8) Working conditions are good there little rise the ambient temperature. (9) The baking uniform the lamps may set eliminate shadows and avoid over-illuminated spots. (10) The heat can directed and confined the desired zone giving high heating efficiency. (11) Improperly baked jobs are noticed once and can cor- rected. (12) Baking conditions, once set their best, can rigidly main- tained keeping the voltage, speed travel work, air conditions, etc. (13) Large surfaces baked radiant heat had best kept ver- tical for uniform heating. This difficult convection ovens. (14) Massive products are also more easily handled radiant heat than convection ovens. (15) “case hardening” ex- perienced and surface film inter- feres with the escape the sol- vents. (16) There chilling, wrinkling, crystallization other form reduction gloss. (17) The entire installation highly flexible and finishing sched- ules can easily changed. For installation and operation the following factors must con- sidered: blacks absorb heat, are quick baking; whites reflect heat and are, therefore, slow. Solid prod- ucts, such as, rods, spheres, mas- sive pieces, etc., bake more slowly than sheet metal the greater mass the metal conducts heat away more rapidly. Wrinkle finishes tend flatten out under radiant heat rays and must formulated specially for this type baking. Lamps emitting over per cent the energy input the form radiant heat rays, are available 250, 500, 1000 watt sizes with sep- arate reflectors. Gold plated reflec- tors reflect about per cent the radiant heat; oxidized alumi- num, 75-91 per cent. Silver excellent reflector but its life short because its rapid tarnish- ing. new coating for reflectors, which has attracted some attention, vaporized aluminum which said have permanence, the ability withstand temperature and reflec- tivity higher than that gold under mean life conditions. Clean, open reflectors may maintained wiping with cotton batting dipped proper thinner. caustic soda oz. trisodium phosphate per gal. water, per cent hydrochloric acid; then rinse and polish lightly. Reflectors may set for conver- gent, divergent parallel rays. Sealed lenses and reflectors are available for 1000 watt lamps and have improved and widened the scope radiant heat baking. Energy requirements are from watts per sq. in. work. Sheet steel painted black may baked out 280 deg. min. about watts per sq. in.; 500 deg. the same time watts per sq. in. Higher wattages result faster heating and higher efficiency. For that reason, high wattage ad- visable the entrance the bak- = ing chamber, raise the tempera- ture quickly; and then hold the temperature the body the oven lower wattages. Care must taken avoid drafts, losing efficiency exces- sive convection. course, some vent necessary remove solvent vapors. Cleaning Cold Rolled Steel Lyons, Jr., the Meaker Co., Chicago, described the rolling steel produce the new highly fin- ished materials and then pointed out how the various lubricants used cold rolling are removed prior plating. remove saponifiable oils use alkaline bath over 190 deg. Silicates are suitable provided their not too high; also caustic soda. Silicates, phosphates and wet- ting agents reduce the time of, cleaning. For rapid work, electrocleaning desirable 100 amp. per sq. ft. Both anodic and cathodic cleaning are satisfactory, but the author recommended, the anodic method. Excessive foam due soap formation, may kept down the use small amount kerosene. Small parts may cleaned tumbling spray washing. Paraffin and soluble oils may cleaned dipping rinsing with warm water with the addition little soap. these oils have been rolled the mill and annealed, much stronger cleaners are neces- sary and sometimes the dirt hard, made decomposed organics, almost impossible remove. Degreasing annealing saves considerable trouble later cleaning. Another contaminant the inhibitor used pickling. electrolytic strip cleaning process has been developed keep with the four-high mill produc- tion. The following sequence used for hot tinning: (1) Spray washing warm, weakly alkaline solution, which removes most the grease, (2) electrolytic cleaning cell, cleaning hot alka- line solution current density 50-60 amp. per sq. ft., (3) wring- rolls, (4) rinse tank, (5) dry and coil for annealing. The total time for operations about 120-150 ft. per min. Speeds 300 ft. per min. this cycle have worked satisfactorily. Since adding scrubbers and other im- provements the line, the above cycle has been speeded rate 2000 ft. per min., cutting down the total time involved the clean- ing cycle sec. For cleaning cold rolled steel, mixture recommended composed sodium orthosilicate meta- silicate oz. per gal.; sodium hydrate oz. per gal. The most important factor the condition the oil. not decomposed, may very difficult. sible clean without using burn off flame treating fused sodi- hydrate the cathode, an- nealing molten lead. also possible use cleaners based solutions emulsifying and defloc- culating agents kerosene sim- ilar solvents which the work may soaked, rinsed, and then cleaned aqueous alkaline bath with current. Care must exercised keep the kerosene from dissolving some the contaminants and con- taminating other steel. cathodic cleaning, add little zinc oxide dissolved high alka- line cleaner. thin film zine deposits the cleaned portions and the hydrogen evolution concen- trates the dirty portions the work. The zinc then dissolved the pickle. strong anodic electropickling solution may used (20 per cent sulphuric acid) and the elec- tropickling and the alkaline electro- cleaning cycle may used but this procedure may found slow. Rectifiers for Electroplating Copper oxide rectifiers for the electroplating industry were dis- cussed Albert Lee, General Electric Co., Bridgeport, Conn. The author described rectifier with moving parts except cooling fan; other words, electronic valve which permits the current only one way and not return alternate a.c. The rectifier element the cop- per oxide type copper plate with coat red oxide and top coat reduced copper; then nickel plate. number these plates are assembled into stack and mounted into casing with transformer, control device, blower, etc. Comparing the operation the rectifier with the motor generator set, the author summarizes: (1) output current equal that the motor generator set; (2) recti- fier reliable and long-lived there electrolytic action; (3) the operation cool; (4) the effi- ciency high voltage con- trolled transformer taps and there need for tank rheostats long bus lines the rectifier set the tank; (5) the rectifier made standard sizes and design units and may built any combination any desired capac- ity. general, the copper oxide rec- tifier recommended machine for doing the same job the motor generator set, but more efficiently and lower cost. “The Effect Copper Cyanide Solutions the Adhesion Copper, Nickel and Chromium Finish Die Castings,” was the title paper presented Mar- tin Maher, Etched Products often occurs such blistering un- der color buffing copper, after nickel and chromium, even later, the baking organic finishes die castings. eliminate such difficulties, care must exercised not overclean the work. Low con- centration alkaline cleaners and short periods immersion were advised. test run was made deter- mine the optimum number parts treated identically except for pH, which was varied from 11.8 12.6, steps 0.4. Most blistering occurred the parts plated between 12.2 and 12.6. The optimum point was 9.4. lower pH, the copper solution was satisfactory but the deposits turned matte, brick red. This was overcome the use sodium thiosulfate. Uhlig, General Electric Co., Schenectady, Y., read pa- per Electropolishing based similar paper presented Octo- ber, 1940, the meeting the Electrochemical Society, the use glycerine-phosphoric acid mix- ture for electrolytically polishing 18-8 stainless steel. Best conditions for polishing were determined photoelectric spectrophotometer. Best polish was obtained with per cent glycerine; per cent weight 100 deg. more, and 0.1 amp. per sq. in. Other organic addition agents phosphoric acid also produce good electrolytes. These substances are THE IRON AGE, July 1941—43 iF } | | i | 4 generally high boiling containing one more hydroxyl groups soluble Nickel, copper, chromium steels (18-8) con- taining and mild steel similar 18-8 can polished such electrolytes. Organic additions have two effects: (1) change electro- lyte and anode phosphate film con- ductivity produce optimum ish; (2) considerable retardation localized pickling anode tion. Polishing stainless steel easier than iron. Composition Cathode Films Abner Brenner, National Bureau Standards, Washington, said his presentation that cathode films may investigated the freez- flat plate cathode. was found that the film the cathode about 0.01 in. thick was markedly depleted metal; that outside this film existed convection area which metal circulated and that metal moved from convection area the film diffusion. The time dif- fusion for the cathode film was found about min., atter which condition existed. Agitation the thickness the film and also re- sults less depletion metal. Conversely agitation increases the proportion sulphuric acid the acid copper bath; and with agita- tion the cyanide bath, cyanide increases while silver decreases the cathode film. “Electrocolor and was paper Dr. Starek, United Chromium, Inc., New York. The process described covers the electroplating colors directly base metal; other words, the production final colors elec- trolytic process. All colors the visible spectrum from one solution. variety patterns may obtained different sizes and shapes; also from solution. These patterns may plated over with any other metal. Some the above finishes, particularly the col- ors, are given final coat clear lacquer. The color plates are called Elec- trocolor, the patterns, Patternplate. The base metal prepared buffing, scratch-brushing, cleaning, usual. Copper brass may take either Electrocolor Pattern- plate directly. Other metals, such 44—THE IRON AGE, July steel, zinc, etc., are given copper plate, then the Electrocolor Patternplate. Two-tone com- bination plates are easily obtain- able. The color plating done alkaline organic cupric solution volt, 70-110 deg. (Deposition faster the higher tempera- tures.) Current density, amp. per sq. ft. high cathode efficiency obtained and pos- sible plate 0.001 in. per hr. The deposit which cuprous oxide, rinsed, dried and clear lacquered. The color the plate depends upon the thickness and therefore, the time plating. easily controllable thickness and uni- formity. Throwing power very high. Colors the very thin plates are the light interference type. The heavier plates give pigmen- tary color which thick, strong and will stand buffing. Patternplate requires basic deposit copper. The pattern size depends upon the plating time; the longer the time, the larger the pat- tern. The bath the same used for color plating and the first de- posit cuprous oxide which then reduced certain areas copper, starting reduction nuclei. Various patterns are obtainable, such crystal, fern, etc. Subse- quent plating improves the corro- sion resistance. The adherence both Electrocolor and Patternplate excellent, the work stands bend- ing, forming, punching and shear- ing. Large areas are plated satis- in., for example, brass and steel. These sheets are blanked out into letter-box doors and other similar parts fabricated from the ished metal. Anodes are electrolytic copper, and temperature is, course, auto- matically controlled. special volt generator must for this class work. Solutions are not critical but can main- tained and need not thrown away. Copper Plating Nemours Co., Wilmington, Del., discussed modern methods cop- per plating. Copper cyanide solu- tion was introduced about 1840. Later developments Rochelle salt solution and the pres- ent day high speed copper process developed Pont. The subject copper plating particular interest this time because the general substitution copper for much the work formerly done nickel. The uses for copper plate include light 0.0003 in. undercoat for nickel; moder- ate coatings 0.0003 0.001 in. steel before case hardening and some instances heavy thicknesses even 0.003 in.; heavy thick- nesses—0.0006 0.002 in. steel later buffed and with bright nickel; cleaning and plating strike flash applied be- fore the regular copper deposit. Copper may deposited good coatings die castings prior nickel plating. power copper solutions aids the protection the parts which nickel would not reach. With the aid modern copper solutions, routine can established which shows considerable savings over past methods. Two these routines are follows: (1) Polish and color buff (2) Copper plate 0.001 in. (3) Bright 0.0005 in. (4) Chromium plate. (1) Polish (2) 0.0015 in. (3) Copper buff (4) Copper plate light-—0.0005 in. (5) Bright nickel plate (6) Chromium plate. Routine provides highly rust resistant finish. nickel—0.0003 Modern high speed solutions have increased production greatly with- out the need for new equipment. The deposits are uniform, adherent and the coatings have good, not high luster even heavy thicknesses. The anodes consist cathode copper sheet, kept clean and bright and the solutions are easily controllable. Perfect cleaning necessary and the anodic type recommended. best use strike solu- tion with carefully controlled cy- anide content. Filtering with ac- tivated carbon necessary keep the solution free organic and in- organic impurities. Use soft water. Circulate the solution mechan- ically around the anodes well the work. Air should not used.) Current densities above amp. per sq. ft. result excessive (CONCLUDED PAGE 92) ~ | HERE sufficient informa- tion make the art tool hardening science; how- ever, this information can only used insofar helps explain the best method for hard- ening tools. Like most other dis- coveries, the best methods for hard- ening tools were discovered first and the scientific explanation came later. Since tool hardening depart- ments bear very little resemblance one plant another, at- tempt will made put tool hard- ening scientific basis. Yet standard will set that can attained approached any plant. Tool hardening technique de- termined many conditions. should not said that the best method for tool hardening heat the tool rapidly heat the tool slowly with careful preheat- ing, for the type furnace, fur- nace atmosphere, characteristics the steel, must considered. Therefore, definite rules are not tabulated. Many men with all sorts equipment are doing good tool hardening, and the art quite easy understand. the other hand, correct methods for hardening tool steels can best brought out through discussion the hard- ening the steels list