Hand Tools

Subject:
More on practical chiseling

Bill Tindall, E.Tn.
Summary- harder wood doesn't take more strikes. Higher resistance chisels don't take more strikes. Why, chops are not made at equal force. Force is proportioned to achieve a desired penetration. Time to conclusion winds up the same. Total work, not significant for these tasks. Total time, significant and equivalent.

Chopped an equivalent dovetail in hard maple. 6 dainty chops to establish initial baseline. 10 more to complete the 1/2" depth. (recall it was 4 and 10 in ash)

It may be that I don't chop out waste like anyone else, but don't put a lot of money on that bet. I have chopped many feet of dovetails on cases and drawers in the last decade. I'm lazy and look for efficiency where ever I can find it. So do some others.

I did not do pine or poplar but considering what I was using for feedback I believe the number of chops would have been about the same.

I don't chop with the same force each time. At first the force grows proportionally and depends on the support the base line shoulder provides. The deeper the cut, the taller the base line, the better the support to drive the chisel deeper. But, at some depth the deflection becomes the limiting factor. I found myself bashing to get depth that would not result in unacceptable deflection. The bash force was adjusted by this feed back, not wood resistance, which was easy to overcome with modest increase in bash force. (I bash with a small rubber mallet, lighter in weight than what many people use. )

While David's experiment was convincing for comparing edge durability, it would not predict how I would rank the chisels in how many strikes (and in turn how much time) it would take to chop out a dovetail waste. I would find them all the same with no concern for the small difference in force exerted.

That said, a more acute bevel angle would result in less deflection. I think I would respond to that fact with deeper blows resulting in faster production. For my application, more durability and better penetration are selling points. The number of bashes to get across 1" is not relevant to the way I work. These data would confuse the attributes I find important.

Now you can decide how strange I am and adjust emphasis accordingly. I don't have a horse in the race from here out. I know what Unicorning will do for me in putting product out the door and it is significant.

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