28 



Hardwood Record — Veneer & Panel Section 



February 25, 1917 



Pointers for Veneer Users 



The Problem of Taking Care of Natural Tendencies of Veneer Is an 



Interesting One 



OMETIMES CONDITIONS ARE MET WITH 

 that raise the question as to whether theories 

 form the basis for practice or practice forms 

 the starting place for theories. It is the same 

 thing, stated in another way, with that idea that quite 

 commonly human nature comes to certain conclusions 

 by unknown means, then seeks for logic with which to 

 support the conclusions, instead of taking a stand in a 

 matter by logic previously followed and used in deter- 

 mining a point. Also, it looks a little bit like the hen- 

 and-egg question, in that it is puzzling sometimes as to 

 which came first. Tliis may sound odd to some, espe- 

 cially those who think they develop all their practices 

 from fine theories amended to fit the practice, but if 

 you will study the matter and trace it back to starting 

 points, you may find quite frequently that many theories 

 were formed after practice had developed certain effects 

 to call forth the theories, and thus practice preceded 

 theory. 



To illustrate, there was a discussion on with the 

 superintendent of a plant making veneered doors, and 

 the subject turned on the difficulties encountered in 

 matching crotch mahogany and other figured woods and 

 making a good job of it on the solid core without cross- 

 banding. It has been persistently argued that the only 

 way to make up work of this kind is to crossband it and 

 make it five-ply. Following this theory in making either 

 panels for doors or for furniture, when one makes a 

 good core carefully out of dry stock, then has, say, 

 crotch mahogany veneer to face it with, has it thor- 

 oughly dry and in proper shape, then matches it up and 

 puts it together carefully, according to practically all the 

 better theories, this should insure a good job. Strange 

 to say, however, it doesn't always do so. There are 

 men who put up work just as carefully as they know how 

 in this way, following out very patiently the finest 

 theories, and then find that it will show up badly. Some- 

 times it is a matter of checks, the fine lines marring the 

 face, and at other times the work seems to crawl and 

 open the joints just as if it had not been thoroughly dry. 

 This is one of the conditions that puzzle some who have 

 been at it a long time. All the work will not do this. 

 There may be quite a lot put up that will stand all right, 

 and then again some will open at the joints and show up 

 badly after it is finished. 



These things, some claim, there are no specific theories 

 for, yet unconsciously they do build a practice around 

 them that suggests theories that have been formed after 

 certain practices have demonstrated remedies which may 

 be applied. One of these practices in such cases is to 



keep the stock in clamps much longer than is usually 

 allowed. If it is kept in the clamps, say, forty-eight 

 hours, the chances are it will not do much creeping 

 afterward. At least, this has been effective in many 

 instances. This immediately gives rise to the theory that 

 there are certain expansive and contracting properties 

 set up in the face wood in the process of veneering, 

 which remain active probably until the moisture is all 

 exhausted from the w^ood, consequently if the work is 

 released from the clamps in six, eight or ten hours, the 

 strains thus set up may cause a little movement of the 

 face veneer on the glue. In other words, the glue is not 

 firmly enough set yet to prevent some movement of the 

 face stock under stress of shrinking, but if kept in the 

 clamp until the glue is thoroughly set and until the 

 strains have left the wood, there is not nearly the like- 

 lihood of defects setting up. 



One might argue that this would mean a holding 

 together at the joints all right, but would lead to the 

 fine checks that are so often complained about in ma- 

 hogany crotch work, especially where it has considerable 

 end grain. Sometimes it may lead to this, too, but the 

 fact that it doesn't creep enables us to build another 

 theory, or, rather, go back and take the theory out of 

 some other lines of work and apply it in connection with 

 veneering. There is such a thing as compressing wood 

 and of bending wood to various shapes, retaining it in 

 that position until practically all the strains set up by the 

 bending or compressing exhaust their strength and dis- 

 appear. Then the wood will remain practically as it is 

 bent or compressed. We have many examples of this 

 in the vehicle woodwork line, in bending wagon rims 

 and in compressing some patent hubs. Nearly every- 

 body knows about bent work and how it can be boiled 

 or steamed and bent in various shapes, and that by 

 being confined in this shape and heated until the mois- 

 ture all dries out, it retains shape indefinitely. An- 

 other practice met with is in compressing wood endwise 

 to expand it sidewise — and a sort of patent process, by 

 which it retains its shape and remains hard. In other 

 words, a loose, round piece of elm is compressed into a 

 cast hub form or band, which it fits into loosely, ai«d is 

 put under pressure and compressed endwise until it fits 

 tightly, and, after being kept this way for a certain period, 

 and being treated with certain chemicals, it retains this 

 form and remains tight indefinitely. 



Now, then, applying this theory to crotch mahogany, 

 where we deal with considerable end wood, we may get 

 two ideas. One is to keep the work in the press longer 

 than is the usual practice; the other is to moisten the 



