[OP]
Member
Studying the links Hilton provided and actual pegs in an antique the wife has, I can see that it is not uncommon for the wood around the drawbore hole to split. Any hints about how to prevent this from occurring? The splitting issue seems to be the major challenge with this joint.
Contributor
My use of this joint is limited so this is only theory. One expression comes to mind, "the offset should be about the thickness of a worn half Shilling."Originally Posted by Mike Holbrook
Maybe some woodworkers make the offset overly fat causing stress which displays itself by splitting.
Usually after the part about "a worn half Shilling," everyone comes up empty to the question of, "how thick is a worn half Shilling?"
I usually go with about 1/32" for a 3/8" bore.
One also must be careful if using tapered pegs to stop before stressing the pieces.
jtk
Last edited by Jim Koepke; 11-07-2013 at 2:11 AM. Reason: stopping
"A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty."
- Sir Winston Churchill (1874-1965)
Contributor
I think if you position the pegs with the grain perpendicular to the grain in the work piece then any cross grain expansion on behalf of the peg will not adversely affect the work piece. The the splitting is probably more common when different species of pegs are used to that of the work piece.
"If you have all your fingers, you can convert to Metric"
Guest
Kingshott used a chisel to make his peg.
Member
What kind of chisel, Jack? Japanese or Western
Sorry, I'm just being a dink...ignore me.
Woodworking is terrific for keeping in shape, but it's also a deadly serious killing system...
Contributor
I'm just going by a book I have that specifies oak, but the locust makes sense to me. I would guess that the author used oak because many of his frames were principally or totally oak, so offcuts would be handy in that species from other projects.
Trevor Walsh
TWDesignShop
Member
What about hickory? How would that work for pegs? I have some around but it has a lot of defects so its not much good for anything other than things like pegs and small shop projects.
Woodworking is terrific for keeping in shape, but it's also a deadly serious killing system...
[OP]
Member
Jack, in his DVD Kingshott roughs out his pin/peg with a chisel then drives it through a dowel plate.
I think the text I read suggested that the older drill bits often left a rough spot in the drilled hole, apparently a corner left on the hand made pin might catch in the rough spot and wedge the wood fibers apart causing a split, just like a wedge does.
Member
I drawbore all my MT joints, only because my tenons tend to be on the looser side.
I've used premade dowels and it works just fine.
But, for those times that I've made my own pegs, I cut off about a 3-4" piece of a board (used white oak and maple with success). Stood the cut-off up on my bench, stood a chisel up on end on the board and split off a piece. Then I split that down again in half to get a squarish peg. Used the chisel to whittle down the end and then drove it through my dowel plate.
Guest
Kingshott had mostly converted to using Japanese at the time of the video.What kind of chisel, Jack? Japanese or Western
Sorry, I'm just being a dink...ignore me.
Guest
Maybe it's time to rewatch the dvd's. As to rough spots, all you need do is chamfer the leading edge.
Member
FWIW, I use a pencil sharpener to chamfer the front of my drawbore pegs to aide in driving them in although in larger ones, I taper 'em a bit too.
" Be willing to make mistakes in your basements, garages, apartments and palaces. I have made many. Your first attempts may be poor. They will not be futile. " - M.S. Bickford, Mouldings In Practice
[OP]
Member
I also noticed that Kingshott used a single peg/pin in his demo vs the doubles I frequently see used in projects. I wonder if he did it just to make the DVD move faster or if that is his normal way of making them. I don't think he commented about it on the DVD. I have seen quite a few splits running between the double drawbores I have seen. The antique chest the wife has, has splits running between several of the double drawbores in the chest and door frames. I'm not sure what the wood is but it seems prone to splitting as there are splits in several boards too. A poster above (Mel) mentions that a restoration shop he worked at would not let him make drawbores, sounds like they pegged straight holes?
I guess the doubles tighten things up more evenly without having to worry about things being centered as perfectly, whereas the single pin may reduce the risk of splits. Mel mentions clamping, maybe clamping would provide a certain amount of firmness in the joint without the offset hole trick? I suspect the condition and species of a particular piece of wood might determine which method might be appropriate.
Last edited by Mike Holbrook; 11-08-2013 at 10:35 AM.
Contributor
Sorry, double post
Last edited by Frank Pratt; 11-10-2013 at 1:58 AM.
Contributor
I needed 32 pins for my workbench base & didn't really want to make them so I bought some 1/2" white oak dowel from Lee Valley. They advertise that it is precision stuff & it was exactly 1/2" in diameter & straight grained enough that there was only about 25% waste. I chamfered the ends & used a large hammer to drive them into the hard maple base.
I made up several test mortise & tenon joints & drilled the holes at various offsets. The joints were then glued, pinned & allowed to dry. Then I dissected each one to see the results. The optimum hole offset seemed to be 3/32"
The joints came together super tight with no splitting.
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