I am building a TF sugar shanty using the Jack Sobon garden shed design, and I was wondering if draw boring is common practice or if most of you drill and peg after the joint is together.
Nick
Draw bore everything. If you don't, you will get gaps as the timbers shrink.
Although I don't do it for a living and only have a handful of frames under my belt, I was taught to drawbore and it makes sense to me, especially for green wood. Draw boring allows you to go back and whack the pegs again to tighten up if needed. This makes sense for green wood, but is also good if needed for seasoned wood. Seasoned wood you shouldn't need to, but it doesn't hurt giving you that option.
I was taught to make pegs by riving a green oak log chunk with a froe, keeping the rivings wet in a rubbermaid rectangular storage container with water until you go to shave it. Then shave it down on a shaving horse with draw knive takes about 60 seconds or so per peg(tapered peg). Fast, cheap... I know timberframers who have their kids make pegs.
For what it's worth, I draw bore everything. The one time I didn't, I wish I would have. That was on a small king post truss and the way it fit together, once I got everything to fit I really didn't want to take it apart again to drawbore it. So, I just ratchet strapped it and drilled the peg holes and pegged it. It turned out alright, but not as good as all the other joints that I did drawbore.
Thanks guys. Brad, do you keep the pegs wet after you shave them too?
No, they can dry after they are finished. You want to keep them wet so that they are easy to shave(much softer). Also note that if your peg blanks dry out, you cannot put them in water and re-wet them. Due to the structure of oak, the water will only resoften the outside 1/32nd or so of the wood. It will not let water back in throughout. That's why it's important to rive a green log chunk, and put the blanks right in water to prevent it's water from going out.
Rough out your billet and store it in a bucket of water. This will keep everything wet until you need it.
Not to hijack the thread, but how much of an offset needs to be drilled for draw boring? Are the pegs also tapered along the whole length of them?
1/8"
I don't have a picture handy, but tapered from the tip to about 3 inches from the outside end (where you are clamping in your shaving horse you cannot shave, but it works out perfectly).
Quote from: Brad_bb on December 03, 2011, 09:50:50 AM
1/8"
I don't have a picture handy, but tapered from the tip to about 3 inches from the outside end (where you are clamping in your shaving horse you cannot shave, but it works out perfectly).
Thank you.
Here's one video I found on youtube. The chunk he is using is pretty dry as he said he took it from a firewood pile for the demo. But you want to work a green chunk that you keep wet. It shaves much easier and smoother that way. Dry oak can come off in chunks when dry. It's really easy to take too big a bite with the draw knife when it's dry.
http://youtu.be/i6l6SMihNNE (http://youtu.be/i6l6SMihNNE)
1/8th " is a good rule of thumb. If your working softwood with lots of relish kick it up a notch. Especially if you have green wood(timbers). I have always(when I haven't bought them) rived out of well seasoned locust or white oak and then dressed them with a draw knife or a spokeshave. Buying them is pretty cost efficient and you have lots of options and species to choose from. If you don't have a froe you can split pretty straight grain stuff with a hatchet and a mallet. Make sure your pegs are very dry before putting them into service. They won't shrink and have optimum strength.
Draw bore religiously. A little draw boring hymn "To the end is a dead end". If you are moving towards the end of a tenon you are going the long way. Things can get a little confusing in some joints (scarfs and splines) but if you make good habit, like most skills they become second nature.
I know Brad, and Heartwood! 8)
I've found it's better to have a little too much draw bore than not enough. I like to visually check the peg holes at assembly, and if it is a little too much draw, you can always clean it up with a gouge, not enough, and there isn't much you can do without plugging and redrilling.
Quote from: Jayson on December 03, 2011, 09:10:09 PM
A little draw boring hymn "To the end is a dead end".
and to the shoulder, it will hold 'er :D
Dang it, that's the one I was trying to remember!
Quote from: Dave Shepard on December 03, 2011, 09:20:09 PM
not enough (draw), and there isn't much you can do without plugging and redrilling.
That would make for a great video.
Yup, that's me in black fly season trying to do an impromptu video with a crappy froe, and old wood.
Thanks for hooking HW up with some decent peg stock this year. A little round goes a long way. And by the way (Dave), I had heard through the rumor mill someone was working on some dutch barns, and I was a little worried until I figured out it was you. Don't want a nice old Dutch barn getting all hacked up. I know you'll do a good job. I don't think I've seen you since Bing's raising, and man that was a tough one. All hardwood, and lots of different people who worked on the frame over a really long period of time. There were a few things that I missed too, but it all went together, and it looks great.
Dave Carlon always says to offset the peg hole in the direction you want the other piece to move. It's easy enough with a straight mortise and tenon, but rafter peaks and weird things can be counter-intuitive.
Hi Brad, thanks for stopping in! That was one great oak log that those rounds came from. I busted up another for a raising in New York last month. I'll be working on the second barn all winter, you are welcome to stop in. Will was down to the shop last night with the Berkshire Wood Workers Guild for a tour.
I was just wondering I'm building a post and frame sawmill shed this coming year out of white pine. I'm planning on draw boring the joints. I also have some maples on the property would the maple work for my pegs or should I be looking for something else. I don't have any oak that I want to cut.
Maple is fine, use what you've got.
Jim Rogers
Also it wouldn't hurt to spray or dip your pegs with a borate to keep PPB away If they are exposed outside.