Draw Bore Question - Pin Species

[Joe A Faulkner]

I am planning to draw bore some Joints in a King size Solid cherry head board. I’ve never done this before. I’m thinking of using walnut for the pins. I have red oak and white oak on hand. And could use cherry as well. I’m thinking the contrast of walnut will look the best. I’ll likely use glue as well. Any considerations as to pin species selection that I should be aware of? I will rive the pins from dry stock.

[Derek Cohen]

Joe, my thought, which guides my choice here, is that the pin needs to have some flexibility to bend a little. Rigid, short-grained wood is likely to crack. Riven pegs offer the best chance of creating the ideal properties.

I would use Cherry scraps from your build (unless you want the contrast of an Ebony). Once you finish, the end grain of all woods, such as your Cherry, will darken similarly.

Regards from Perth

Derek

[Jason Buresh]

There is a free article online called "Draw boring resurrected" if you Google it.

It was written by Christopher Schwarz and he goes into peg sizes, offset etc. It may be a good reference for you

[Prashun Patel]

My preference for a drawbore pin that needs to flex would be white oak. The walnut may work fine but white oak is harder. The end grain of the white oak will make a great contrast to cherry.

[Andrew Hughes]

I would choose the white too. It’s the strongest and most flexible of the woods you mentioned.
Riven and hammered thru a dowel plate.
Good Luck 0

[Warren Mickley]

On historic work the pins are just about always the same species as the joint they are going in. There is a good reason for that. When a pin goes in an offset hole, there is deformation, bending or crushing or both. The best situation is that this deformation is shared, some in the joint, some in the pin. A white oak pin will just blow right through a white pine joint crushing everything in its way and a white pine pin in oak will just get crushed.

Historically the makers were not trying to call attention to the joinery; if they wanted decoration it was more likely mouldings or carvings or turnings. However, if you want to call attention to the pins, a walnut cherry combination is not too bad because they have hardness in the same range.

[Rob Luter]

I guess I'll ask what your goal is? Are you doing this for structural reasons to draw the joint together or for aesthetic reasons because you like the look of a pegged joint?

If doing so for structural reasons, pay close attention to both the location of the hole relative to the end of the tenon and the amount of offset between the holes through the mortise and the hole through the tenon. If you get too close to the end or get too aggressive with the offset, you can blow out the end of the tenon. DAMHIKT.

I peg M&T joints quite frequently in my projects and generally use very little offset. They are primarily for aesthetic reasons as I like the traditional look. I usually glue the joint anyway and the pegs let me get it out of the clamps faster. I suppose it's good insurance against the glue letting go sometime in the future too.

I normally use the same species for the pegs as the project is made from. The end grain usually finishes much darker than face grain so I get plenty of contrast without having to use a different wood species. Sometimes I leave the pegs a little proud if I want to enhance the look.

[Edward Weber]

On historic work the pins are just about always the same species as the joint they are going in. There is a good reason for that. When a pin goes in an offset hole, there is deformation, bending or crushing or both. The best situation is that this deformation is shared, some in the joint, some in the pin. A white oak pin will just blow right through a white pine joint crushing everything in its way and a white pine pin in oak will just get crushed.

Historically the makers were not trying to call attention to the joinery; if they wanted decoration it was more likely mouldings or carvings or turnings. However, if you want to call attention to the pins, a walnut cherry combination is not too bad because they have hardness in the same range.


This would be my choice also.

[Tom M King]

In working on old window sash, as in a couple of hundred years old, the most common failure is from draw bored pegs blowing out the tenon. When using dry wood, I don't drawbore just for grins. I just clamp tight, and pin it. I'm not trying to tell anyone how they should do their work, but just adding something to think about. It doesn't take much for small stuff, like furniture.

[Lee Schierer]

My understanding is that the pins need to be green wood so they will flex as they are driven in and riven pegs are better than sawed pegs.

[John Keeton]

Our timber framed great room was constructed with green red oak timbers and kiln dried straight grain pegs. When the timbers dried, they shrank and seized on the pegs. I doubt one could extract one of the pegs with any amount of force. When one constructs a chair, bone dry tenons are inserted into mortised components that are in ambient conditions with more moisture than the tenon with the same result as with the timber frame.

I agree that the peg/pin needs to be of the same species and needs to be dry, preferably with less moisture content that the joint components.

[Charles Guest]

The OP states "I've never done this before..."

Just clamp, bore, glue and pin. Don't worry about actually drawboring. The pins will help hold the joint, and you'll get the aesthetic effect you're going for. If you do drawbore, make some trial joints first and saw them apart to see if it worked (tenon didn't split, etc.). A headboard is a large chunk of wood to honk up.

Here's Chris Becksvoort pinning (not drawboring) a joint, and a link to his website:

https://www.finewoodworking.com/2006/10/29/pinning-a-mortise-and-tenon-joint

(https://www.finewoodworking.com/2006/10/29/pinning-a-mortise-and-tenon-joint)https://www.chbecksvoort.com/

[Edward Weber]

The OP states "I've never done this before..."

Just clamp, bore, glue and pin. Don't worry about actually drawboring. The pins will help hold the joint, and you'll get the aesthetic effect you're going for. If you do drawbore, make some trial joints first and saw them apart to see if it worked (tenon didn't split, etc.). A headboard is a large chunk of wood to honk up.

Here's Chris Becksvoort pinning (not drawboring) a joint, and a link to his website:

https://www.finewoodworking.com/2006/10/29/pinning-a-mortise-and-tenon-joint

(https://www.finewoodworking.com/2006/10/29/pinning-a-mortise-and-tenon-joint)https://www.chbecksvoort.com/

+1
If this is the first time, I would err on the side of caution until you've done it a few times and get the feel for it.
Draw boring is technique designed to draw a joint to a snug fit and hopefully keep it closed during changes in the season. It seems too many people are mistaking this technique for some type of clamping procedure, it's not. The M&T is the joint, the dowel is only there to retain it.. Putting too much stress on the tenon by aggressively wedging a dowel offline can cause an unnecessary failure in an otherwise strong joint.
Straight pinning the tenon,
Once the hole is drilled and the dowel is glued in, the swelling alone caused by the glue will be enough to keep the joint tight and secure without undo pressure on the tenon.
JMHO

[Charles Guest]

Also need to add that some auger bits are made 1/64" over nominal so if you're using a brace and bit, make some trial borings first to make sure the dowel stock or pins you've made are going to be a nice, tight fit. The pins could have dried out, oval'd, etc. Bit and/or brace runout could also ruin your day if it's bad enough.

Put a little chamfer on the end that goes in first. Hide glue will lubricate the pin. If you use liquid hide glue, warm it up in a pan of hot water. You'll need to tap in with a hammer. If you use PVA, you may have to tap in pretty hard. Warm it up too, if it isn't already.

Test everything first! Make trial borings and glue in pin stock until you know exactly what's going to happen and how it all feels. Make trial borings and pinnings to the same depth you'll need when you do the real project. Again, you're doing a headboard and not narrow stiles and rails. You do not want to mess up a component of that size. It is demoralizing and expensive.

[Warren Mickley]

Here in Lancaster County we sometimes move an old timber frame barn or house. We take out the pins, disassemble, and set up the frame again with new pins. We have been doing this for 300 years. Drawboring does not need to be "resurrected".

We use tapered pins for historic work, both buildings and furniture. We do not use dowels. The pins do not need to be riven because when you taper them with a chisel, if the grain is slightly off, the cut will follow the grain and correct a mild slope to the grain. You want to start out with straight grain anyway. In restoration work we take out the pins and put them back in the same holes when reassembling the piece.

If you are using hot hide glue for your mortise and tenon joint, it is nice not to have fool with clamps. So if the holes are slightly offset, you pin it and you are done. Using white glue or yellow glue makes something that we won't want to repair.

[Charles Guest]

"...the dowel stock or pins you've made..."

[Tom M King]

Here's a 200 year old sash that we replaced some broken parts in-the glazing bars. You can see the freshly milled wood color, as opposed to the old, weathered rest of the sash.

Every joint is a mortise, and tenon, with no glue ever used. All the joints around the outside are pinned. This is the same way I build replacement sash-go glue. If there is no glue, all you have to do is knock the pegs out, take it apart, and it goes back together the same way with any replacement parts that are needed.

We never use glue building these old house parts, just like they used to do, whether sash, doors, shutters, or anything else. I still do very little drawboring.

It makes no sense to me to bother to use drawboring, if you are using glue. We drawbore if we are doing some timber framing, including replacing parts with dry timbers, mostly as a little insurance so we don't have to put it together but once.

[Jim Koepke]

Every joint is a mortise, and tenon, with no glue ever used.

My draw bored joints also do not use glue.

This was my first project using draw bore pinning of mortise & tenon joinery > https://sawmillcreek.org/showthread.php?262272 < It is still holding together quite well. Maybe it will be around for another 200 years.

Some of the things learned since then is to set the pin back from the edge of the mortised face about 2-1/2 - 3X the diameter of the pin.

The amount of the offset should at most be about 1/32". Any more and it risks blowing out the tenon.

The pin should have some flex and straight grain, riven if possible. The pins do not have to be round.

If two pins are to be used they should be at least 1-1/2" apart. If this isn't possible then only one pin should be used.

There should be at least 5X the diameter of the pin beyond the pin on the tenon to help avoid blow out of the tenon. The diameter of the pin should not be larger than the thickness of the tenon. Imagine what a half inch pin could do to a quarter inch thick tenon.

Of course, as always 461019

jtk

[Tom M King]

I'll try to remember to take some pictures of some of the old, blown out tenons. I think I still have some laying around.

[Charles Guest]

Not responding to any particular post:

All it takes is a little bit of odd grain runout and the chances of cracking a tenon increase enormously, so, to, if the tenon's grain is too straight, or if your layout leaves you working right on a prominent grain line. And it if doesn't crack, the whole thing might end up being nothing more than a glorified pinned joint, except it might not fit as well as if the original intent were just to pin.

Other than for massive joints like a timber framed barn or house where glue could never be used in the first place, it is a vastly overrated procedure with more downside than upside for furniture.

It's easy (and perhaps foolhardy) to claim success with this procedure while you're still alive, during say a 30 or 40 year career, because that's a tithe of time, essentially nothing. Having seen somebody else's work that's lasted 200+ years doesn't mean yours will. And the old craftsman probably went to his grave with fingers crossed anyway. If you have unlimited access to Cuban mahogany and other old growth lumber species of yore, with growth rings so tight you'd need a magnifying glass to count them, then feel free to ignore what I just wrote. Everything you read about in a 300 year old woodworking manual is not necessarily applicable today.

[Jim Koepke]

Good points Charles.

It might also depend a lot on intent.

Is the draw bore pin being used to secure a joint or is it being used in the hope of pulling together a poorly executed joint.

A minimal misalignment between the holes bored through the mortise & tenon is all that should be needed. Just enough to secure the joint, not enough to stress the joint.

jtk