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In Chris Schwarz's blue workbench book, he mentions that unglued, drawbored pins can be drilled out of a mortise and tenon joint in case the piece (for example, a heavy bench) needs to be disassembled and moved. Could someone with experience doing that speak to how difficult it is? What about re-pegging the joint afterwards? Is it an effective way to produce "knock-down" furniture that doesn't need to be moved very often, without sacrificing rigidity?

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    You're familiar with the difference between a drawbore pin and a simple dowel used to 'peg' a tenon? If you fully drill out a drawbore you can't re-drawbore afterwards because you'll have removed the offset hole in the tenon. But you can by all means peg a tenon (not glueing in the peg obviously) and knock that out without significant harm to the holes in tenon or mortise sides, allowing a certain amount of knock-downability. But a commoner way that M&Ts are used in knock-down furniture is with wedged tusk tenons, which as with drawbores also force the joint tightly together when tapped home.
    – Graphus
    Apr 24 at 18:20
  • A tusked tenon isn't an option for attaching the top of a bench/table to the leg assemblies. I suppose Schwarz was suggesting drilling enough of the bent pin that you don't hit the tenon at all, but weaken the pin enough to break it/yank it out. It's hard for me to imagine how well that would go, though.
    – colinmarc
    Apr 24 at 19:54
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    One unfortunate thing re. Chris that I wanted to mention is that he's always learning and changing his positions on things.... in other words, his recommendations change (and sometimes dramatically). All his stuff, both past and current, needs to be read bearing this in mind. There's no clearer example of this than his flip-flopping about the cap iron/chipbreaker. Earlier on, when he was ignorant of their use, they were bad (spawn of the devil or some such), and then some years later they're the best thing since sliced bread!
    – Graphus
    Apr 25 at 8:07
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    I looked up the quote I was thinking of, it's from 2013, "Chipbreakers were invented in 1846 by the devil" LOL Two things to know here, 1) obviously his later self wouldn't agree with his earlier self, and 2) he got the date wrong! We know cap irons predate the 19th century, and best current evidence is they first appeared in the mid/late 1700s. They quickly gained acceptance and increased in popularity. They were more expensive. These two facts together are strong evidence that they provide a significant benefit, notwithstanding later naysayers who somehow forgot about them entirely o_O
    – Graphus
    Apr 25 at 8:16
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    Good to know he's as fallible as the rest of us :)
    – colinmarc
    Apr 25 at 10:57
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I haven't read the book, so caveat emptor here...

Having said that, a non-blind pin (ie, one that's visible on both sides and far and away the most common approach) can easily be punched out.

I don't know why you'd want to drill, frankly, as you'd risk hitting the tenon and forcing yourself into an ever-expanding cycle of bigger and bigger pins.

Pegging afterwards is probably a bit hit/miss. The action of the drawbore deliberately mutilates fibers in the tenon, and doing that over and over again isn't a winning proposition.

You might look at the google image search results for "pegged trestle arts and crafts table" for some inspiration on external (ie, easy to remove) pegs.

If this was me, and I was opposed to mechanical fasteners, I would peg without drawboring. Or have an incredibly mild drawbore action -- like a 32nd. This would also mean that the fit of the mortise/tenon had to be exemplary and possibly designed to be a bit bigger than typical.

Mechanical fasteners like a "barrel nut" / "cross dowel", combined with a connector bolt with a big flange (ie, example from Rockler) would be my go-to strategy if I wanted something I could take apart and reassemble. Keep in mind that only a few parts need to be disassemble-able: the top needs to come off the legs, and (design depending, of course) the rails connecting the legs. The leg assemblies can be permanently built.

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  • What about pulling a blind pin? Could you put a screw in it and yank it out? I should probably just try that on a test joint...
    – colinmarc
    Apr 25 at 11:00
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    Give the blind pin a shot and let us know. You might leave a good part of it proud (for future yanking with vise grips) and claim that as a design feature. I'd suggest a mild chamfer around the rim of the hole the pin is going into, to minimize the chance of tearing grain when removing. Apr 25 at 14:19

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