42 



Hardwood Record — Veneer & Panel Section 



July 25, 1921 



"Glues and Their Resistance to Steam" 



There is no question under the sun, even that concerning the 

 shape of the earth, upon which there is complete agreement. 

 This is why Hardwood Record has always been glad to give a 

 reasonable amount of space in its columns to the discussion of any 

 subject of interest to the makers or consumers of hardwood lum- 

 ber and veneers, about which there is difference of opinion. A 

 short time ago Hardwood Record carried an article on "Glues 

 and their Resistance to Steam," which was contributed by the 

 representative of one of the largest glue companies in the country. 

 This man is undoubtedly an authority on glues, but his statements 

 were promptly challenged by members of the Monite Waterproof 

 Glue Company. This company was as promptly invited to submit 

 its objections in writing, so that they might be given the same pub- 

 licity as the statements objected to. The result is the following 

 letter from W. F. Leicester, vice-president of the Monite Water- 

 proof Glue Company: 

 "Hardwood Record, 

 "537 South Dearborn Street, 

 "Chicago. 

 "Gentlemen: 



"We feel that the 'authority on glue' who was responsible for 

 the article in the Veneer and Panel Section of the May issue of 

 the Hardwood Record, dealing with GLUES AND THEIR RE- 

 SISTANCE TO STEAM, is far from familiar with his subject, and 

 his article will serve to create a wrong impression with people to 

 whom waterproof glue is still new, while the many approving 

 users of casein glue will be surprised that such misleading state- 

 ments should receive space in this publication. 



"Perusing your advertising, we note the following firms, all of 

 which to our sure knowledge use one or another make of casein 

 waterproof glue at the present time: 



"Anderson-Tully Co. 



"Louisville Veneer Mills. 



"Hanson Ward Veneer Co. 



"Breece Mfg. Co. 



"Wood Mosaic Co. 



"The Mengel Co. 



"St. Louis Basket and Box Co. 



"It seems to us that the article complained of is an injustice 

 to reputable manufacturers of casein glue and the companies above 

 mentioned. 



"The facts relative to casein glue are that the ready mixed 

 glues sold by American manufacturers enjoy a sale running into 

 many millions of pounds annually in the United States; and large 

 quantities are sold for export purposes. It is a significant fact that 

 casein has been used as an adhesive since the days of the Egyp- 

 tians, and its use has been verified and traced through the ages, 

 down to modern times. For the past 50 years casein glues have 

 been largely used in Germany and Switzerland, but the commercial 

 manufacture thereof was only started in the United States in 

 1916. The glue was developed and refined here under the stress 

 of war necessity, and it is to be noted that casein glue, as developed 

 in the United States, is today the form of waterproof adhesive 

 that is the standard of the world, and foreign plywood manufac- 

 turers are now using U. S. manufactured casein glue to the ex- 

 clusion of practically all other forms and makes of waterproof 

 adhesives. 



"The truth of modern casein glue is that its characteristics make 

 it the most practical glue for every woodworking use. It is 

 readily prepared without heat; there is no admixture of chemicals 

 required from the user; it spreads readily with brush or spreader; 

 special and costly apparatus is not required; it sets in three or 

 four hours, and can be machined in twelve hours; the stock does 

 not require heating and glue rooms can be as cool as desired; it 

 has no disagreeable odor. 



"The statement that the life of a silicate of soda glue joint is 

 short, gives a m.ost erroneous impression to one who is unfamiliar 

 with modern casein glues. Silicate of soda cannot be considered 

 as an adhesive for wood-working use. It is a filler, a cheapener, 

 and has been used in conjunction with many glues by manufac- 

 turers who put cost before quality. It should be clearly understood 

 by every user and prospective user of casein waterproof glue that 

 no reputable glue manufacturer incorporates silicate of soda w^ith 

 casein jiluc; to do so is Nj court disaster. The manufacturer of 

 casein glue naturally does not inform the public as to the details 

 of his formulae; it is sufficient to say that the manufacturer who 

 looks to the future is more interested in producing an absolutely 

 per lanent product, than in cheapening his product, with a view 

 to competing with cheap ron-waterproof vegetable glues. 



"The answer to your correspondent's inquiry: "Can you tell 



us what glue will resist the action of steam" is as follows: 



"The United States Governnrient Air Service and Navy have 

 establishf^d definite standards for glue; they are: 



Block Shear Strength 2200tb per-sq. inch 



Plywood: Air Dry, before or after testing by boiling 



2501b per sq. inch 

 Plyw^ood; tested in a wet condition, after boiling 3 hours 



90 tb per sq. inch 



"Large quantities of glue are used by these Government De- 

 partments, and it is bought against sample, which must stand 

 the above tests. The glue which is being purchased by the Govern- 

 ment today is a casein waterproof glue, manufactured by an 

 American company, and of course the Government test figures 

 quoted above are exceeded by this glue. As a matter of fact, 

 it is a simple matter to build panels with casein waterproof glue 

 that will stand practically any water test. The writer has built 

 5 ply birch panels and immersed them in water for ten days, the 

 water has boiled for twelve hours daily, and cooled off at night; 

 yet at the end of the test the glue points w^ere unimpaired. 



"The manufacturer of built up stock who wants to make water- 

 proof panels that he can guarantee should pay some attention to 

 the wood that they are built of. It is not wise to use gum, pine 

 or fir, or any wood that has a large expansion or contraction in 

 the presence of moisture or heat. Birch, beech or maple, or some 

 wood that has a minimum of movement should be used. Then if a 

 really good make of waterproof casein glue is used, preferably one 

 that the manufacturer guarantees to be up to Government speci- 

 fications, there need be no fear of the effect of steam, w^ater or 

 heat on the glue joint. 



It is not necessary to use blood albumen glue to get a water- 

 proof joint. If it was, there would be little waterproof work pro- 

 duced, because few concerns can afford to install ten thousand 

 dollar hot presses such as are required with blood albumen. Fur- 

 ther, the question of odor of the joint arises, when exposed to 

 moisture. 



' The various fantastic linseed oil and formaldehyde formulae 

 mentioned, belong to past decades, and are today nowhere used 

 for waterproofing glue joints. They are impractical, expensive, 

 and largely kill the adhesive strength of the glue. 



"To correct any misunderstanding. let it be understood that 

 the use of casein waterproof glue is increasing rapidly. There 

 are many responsible and influential manufacturers of woodwork 

 that have used this glue for upwards of three years; thus the life 

 of the joint is proved, and the permanence of glued work estab- 

 lished. Another point worthy of note is that there is no unfair 

 monopoly in the manufacture of casein glue. There are no un- 

 expired basic patents, upon the strength of which any one make 

 of glue is forced upon the would-be user. 



"Very truly yours. 

 ■WFL.F (Signed) "W. F. Leicester. 



"Vice-president." 



