Practical Carriage Building
Compiled by M.T. Richardson, Vol.1. 1891
Does the Mortise in an Unseasoned Hub Shrink or Enlarge?
It is claimed by some that it does not matter much if the hubs are not seasoned, as the shrinkage later on will have a tendency to make the spokes tighter. A man who can make such a statement as this must be, to say the least, peculiar. I am no mechanic, but common sense says the mortise in an unseasoned hub does shrink, and consequently loosens the spokes.
I am a blacksmith, and have been in business for forty years, much of the time working on wheels, and this I will say, never work up any unseasoned timber into a wheel. No first-class wheel can be made out of unseasoned or poor timber.
The question is, does the mortise in an unseasoned hub shrink or enlarge? All that I have heard or seen tends to make me believe that the mortise does shrink with the hub. This much I do know, if the hub is not thoroughly seasoned the bands will come loose, and more than once I have put the bands on a hub three times over before they would stay. Now, as the hub shrinks smaller and all around, is it not reasonable to suppose that the mortise shrinks with it?
There is, however, one phase of the question which I think has never been taken into account. Let us suppose a wheel-maker runs short of any particular kind of hubsómore than once I have seen such a caseóbut has plenty of dry spokes and felloes. He procures some hubs, and he knows they are not thoroughly seasoned; but the work will not wait, and he must do the best he can. He makes his mortises in the hubs and drives in his dry spokes. Now the question is, Do the spokes absorb some of the moisture of the hubs, and are they pinched to that extent? If so, most assuredly when all the moisture has dried out from both the hubs and spokes, the latter will become loose.óBy M. D. D.