When to drill peg holes?

Greetings All,

My first (small) frame is progressing nicely. I am at the point of fitting my timbers together in my shop. My question is...When should I drill for my peg holes? Should I drill them during fitting in my shop or should I wait and drill them during my final raising? Is there a benefit one way or another?

Thanks in advance.

You will be very happy if you drill the mortice and after fitting the sections pricking the peg location, turn the drill backwards, pull apart just enough to access the tenon peg hole, off set the tenon peg hole, for the most part a tad closer to the shoulder. Braces are a little different, still closer to the shoulder but away from the but end. This will ensure pegs are pulling joinery together and not pushing apart. Doing it now in the shop means you won't have to pull out a drill during the final assembly, one more thing you won't have to do on a busy day.

I saw couple of videos on the net where people drill all through the joineries the raising day, having joints tight using come along and heavy duty ratchet tie down straps.

Should we offset also the peg hole when the timbers are dried already or is that solution with come along and straps is good enough?

For my own project, I though about using that second method to avoid creating too much tension on tenons.

One thing that I learnt the hard way is that if you drill too far in advance, then the timbers can shrink a little before assembly which means that your holes will be too small. Redrilling them with a standard auger bit won't work as you just push the fibres apart. I split about 3 pegs trying to drive them home and one is still not quite out the other side.

Having said that, my timbers stood outside over the summer while I finished cutting the rest of the joinery so I don't suppose that my experience is typical!

Through the years of participating on this forum I have yet seen any strong proponents of using straps and comealongs to pull joinery together and then boring holes. I would not be concerned with drying of timber changing peg alignment. An exception would be naturally curved timber which should be dried before joinery, like curved brace stock with long tenons.

Again, the sure fire way of ensuring proper peg fitting would be test fit and pricked peg locations with an 1/8 - 3/16 inch draw bore.

Jon, your are not alone, I also worked outside the all summer, but like mentioned Timbeal, I receive my timber dried down to 17-20% from the sawmill, which I guess helped for less twisting, skrinking and crowning, but it still changed a little because of rain, sun and northern wind alternating fast here.

I will drill only the day I assemble the bent for good. are they special recommendations when using strps and come along then?, when i preassemble, it's super tight with 2tons straps and come along all around the bents...

Drawboring is a fine technique. I'd view strap pulled joints as a shortcut, trying to achieve what is better done through offset peg holes. But that's my opinion. So I'd concur with the opinion that you should fit the assembly, mark the holes, then drill them offset by a small margin.
Using straps may be faster (if you haven't much practice) but does not work as well.
That said, some carpenters of the past were known to have used a Spanish windlass for just this purpose, which is a looped rope wrapped around two timbers with a stick between them. The stick is turned, twisting the rope and drawing the ends together. tremendous amounts of leverage can be gained this way, and it is a very useful device for closing particularly stubborn assemblies. Although, if an assembly is stubborn I personally feel as if the joinery should be adjusted until it fits better, not forced together with ropes and straps.

I'm fine adjusting all members at the moment, to avoid forcing like you mentione. And yes I don't have any experience of off-set, that's why I'm thinking about using those straps and come along to avoid any mistake or extra tension of some tenons.. also, my pegs are not tapered as the ones i see on canadian videos. I'm using oversized cylinder pegs that I'm adjusting for the desired fit.

If you are not confident in drawboring, don't do it. It is risky if you don't know it well, you can overdo it and bust the joints if you are not careful, for example.

I actually do not drawbore much, because most of my work does not involve pegging anyway.

that's exactly what I'm afraid of, bust a joint. As I told you my timbers are pretty dried and I can see the checking.

But it looks pretty good in the pre-assembling so far, some millimeters adjustment those days.

No one has yet mentioned that the advantage in drawbore far greater than how it simplifies raising, is how an offset peg will do much to keep a joint tight as the timber seasons.

As the distance in the relationship of the tenon's shoulder to its peghole remains the same as the timber slowly dries, the same is not true of the cheek of the mortise to it's peghole, the distance between them does change - If the peg is not aligned to that future distance, (compensating for shrinkage) the joint will predictably shrink apart.

The Peg is a Spring not for pulling together an ill fitting joint, but for pulling joints tight as the frame seasons in.

Pegholes are for me and most of those I know and work with, the first in the string of operations when a stick hits the horses, yes before mortises are roughed.

Will, are you saying you bore peg holes before the mortice is cut? I tried that once years ago and when my feed screw hit the peg hole I had problems. It is a bugger, the blow out on the inside of a finished mortice, an irritating thing.

I also subscribe to a drawn peg aiding in continually pulling a joint, to some degree. Pulling a frame together with straps and other gear will not help in this. You may succeed in crushing some fibers, though. If you are using nice dry material that may be applied differently.

I think it depends on a few factors whether or not to drawbore.

We don't drawbore much here. Left to my own devices I would probably drawbore more. But, because nobody is on the don't drawbore bandwagon I'm going to explain why we don't do it more here.

We build mostly barns, workshops, garages here. They are cut rough sawn, and usually stay that way. We use white spruce timbers because they are local. We peg with octagonal pegs because we can usually make them out of scrap hardwood in the workshop.

With the green white spruce and what are usually dry white oak octagonal pegs, draw boring doesn't seem to add much other then labor to the job. I admit I'm going by the carpenters gut, rather than engineering number crunching, but with spruce it seems that the grain might crush or shear before the oak pegs would bend providing this spring effect you talk of as it dries. Back in the day when a barn was clad in board and batten there would have been play in the sheathing to allow for the shrinkage of the dimension of a building as the connections of tie beams and girts shrunk. But, these days the shell outside the frame is usually a lot more rigid. Using SIP screws or lags to attach common rafters also stiffens the frame in this regard.

Any draw boring I've done has been in Douglas fir, oak, or white pine. I'm more comfortable draw boring in these woods. The pegs I've used have been tapered round or fashioned with a draw knife. Done well it is an excellent tool for tightening up joints for assembly and greatly reduces raising time. Its also easier to drill straight holes on the sawhorses rather then off a ladder.

Tim -

I remember the lead screw issue from way back, but mortiser's have been part of the process here for some while. Even then making them done, avoiding that internal blowout and knowing the hole was in alignment from one side of the mortise to the other drove the decision as to when to bore.

It's still a question to me for timbers coming from the sawmill dried in a dryer. I guess in that case the spring effect isn't as important as the timber are kind of seasoned already and the offset should then be reduced! The precision is going to be difficult to realise for such a small of set. I feel it too risky to try for my case, but still don't read someone talking about that type of experience. Anyone?

One thing that can add to the issue is when using white pine for the braces and not oak or another hard wood. More risk to damage the tenon if the offset gives too much tension.

My next frame, I'll use green timber, hard wood for braces and I will drawbore...

Neil -

Here in NNE I work EWP almost exclusively, and don't hesitate to draw it, Spruce either, and this typ with tenons cut to snaf thick.

Depending on your geo-locale timber will stabilize at somewhere around 10% a bit below your 17 to 20. Did your sticks work like they were fully seasoned ? Was the material removed dusty & dry ?

I drawbore as well. However, I use a boring machine, so peg holes must come after the mortise is cut, or the chips will bind in the peg hole.

Schnaff/Schnaff, the secret language of New England timber framing.

I have made this point in the past. I draw bore everything. One of the main reasons is to ensure the peg doesn't push the joint apart. Any error in the wrong direction will have the opposite effect as a draw. So I am always over compensating by drawboring. Drilling holes while standing on a ladder, what fun!

As explain before, I got them dried from the sawmill but the climate here is changning a lot (mountains close to the ocean) and I have been working outside alone, from june to september. So that humidity changed a lot during that period, with some rainy periodes and some sunny and/or windy periods.
I could see the timbers twisting or crowning, but nowadays, even if they changed again, they still fit properly when pre assembling.

Those two last week, i had alternatively rain and frost, not easy to make that last part done in those conditions, and the coming weeks are not going to be a lot different.

What do you mean by "sticks" and "material removed dusty"?!

Sticks is short for timbers. The wood that was removed was it dry and dusty or wet and moist?

Jim Rogers

The wood removed when? still don't understand sorry :P

My timbers were first cut a little over the ordered dimensions, then dried and cut again down to the expected dimensions.

When I started working with them, I had to adjust my reference sides to find my "pefect timber". After that, I layed out just before cutting for each timber.

Removed when you roughed out your mortises.

Short term climatic changes of rain wind and swings in humidity, do not effect how a timber seasons which is a years long process, after which there are only seasonal percentage point or two swings in MC. The only exception to this is prolonged exposure to intense sunlight which hyper accelerates drying on the exposed surface and effects radial shrinkage and how the timber checks.

I was only answering your original question as to what people do and why and what are seen as advantages in one way over another, and suggesting there is little need to worry about damaging your joinery with over draw.

This your first project is a learning process, consider maybe doing some of each, and then let time tell you what it might.

Ok! I got it..

Thanks for info. Climate is special up here, but I guess timbers are pretty dried now, even if they still take showers regurlarly..

I might try to drawbore on couple of joints, but I'll not do it on critical places.

One more question: drawboring means that we automaticaly use tapered pegs? What about overdimensioned pegs?!

Drawbore if you understand which direction to offset. even a little. one eigths will not be too much, but you have to have your head wrapped around it. As common practice, we drawbore all but braces, which get drilled in place once posts are plumb.

Nice to hear about the braces, that's one place I didn't want to drawbore as the bird's mouth joints on rafters.

I unfortunately couldn't raise my frame now before winter so I had to store my bents and cover them on the deck. I was done with fine adjusting two of my three bents but couldn't make the last one because of bad weather here in the arctic and the night taking place now.

I'll have to continue in spring time, brace, plug and raise.

I assembled my bents and stacked them on each other before winter, but they are not plugged yet. Hopefully I'll not have two much gaps on joineries, we will see that next spring!!

As mentionned earlier, my timbers are quiet dried already and they have been outside under different weather periods since june, and the pre-assembling look good so far.