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Working on it

Bodging

The term 'bodge' these days tends to refer to a quick and dirty repair, usually of poor quality. An example would be patching up rusty car bodywork using chicken wire and filler instead of cutting out all the rot and welding new pieces in. Traditionally, however, bodging was a common occupation. Bodgers were craftsmen who worked in the woods, cutting branches and working them by hand to produce a variety of pole-shaped items (eg. legs for chairs and tables).

I've recently had cause to replace several rotten oak pegs (trenails) that should have been holding together the ancient oak frame in the back wall of wibble_puppy's house. The proper traditional way to make pegs is to use a drawknife to hand-carve a slightly tapered round peg out of a piece of seasoned, straight-grain, knot-free oak heartwood. The quick, cheating way to do it (a bodge in the modern sense) is to buy a length of oak dowel (wood that's been machined round, like a broom handle) that is slightly too big and use a belt sander to machine just enough off to make it fit. This would likely produce a slightly weaker result, as well as looking less authentic to the trained eye. Which method do you think we went for? :) An additional complication in this case was that the holes in the ancient oak had gone a bit oval and tapered, and the tenon holes were smaller than the outer mortice holes so they needed a lot of careful carving to make them fit well (as opposed to just plugging up the hole without adding any strength to the joint).

This was the most complicated one to make:


It was a very tight fit, and did actually do an excellent job of holding the joint tight.

One of the tools in the traditional bodger's arsenal was the shave horse, used to hold rough pieces of timber while shaping them with a drawknife. It's sort of a medieval Workmate, but much more specialised. I didn't have a shave horse so I had to make do with (surprise!) a Workmate:


It worked, but it was less than ideal - it didn't hold the wood very tightly, the working position wasn't very comfortable, and constantly tightening and loosening the jaw using the screw handle wasted a lot of time. It now seems like I might need to carve lots of pegs to hold together the frame of the new kitchen porch Wibble is having built, so I thought it worth investing the time up front to build myself a proper shavehorse.

The English style of shave horse is called a Bodger's Bench, as opposed to the continental style, called a schnitzelbank (dumbhead). The basic difference is that the English style has two pivoting verticals with a yoke between them, whereas the continental has a single vertical. I chose to make mine in the English style because it seems to me like it will do a better job of clamping the work. I understand the advantage of the continental style is that it's quicker and easier to slot a long branch in from the side rather than feeding it through the gap under the yoke. I loosely based my bench on this design, adapting it to suit what materials I had to hand, and also sacrificing the ability to dismantle it in order to save build-time. The main materials used were a couple of old wormy oak floorboards, some bits of pine from the old airing cupboard (now demolished because the hot water cylinder has moved and the bathroom is being rearranged), a couple of pieces of pine from the dummy window frames (no longer needed because the real windows have been installed), some bits of pine batten from the (demolished) plasterboard ceiling in the sitting room, and a small offcut of seasoned oak plank. The only materials I bought were a broom handle to make the footrests and a couple of long coach screws for the pivots.

Here is the completed bench, complete with the first test piece (a bit of square pine I carved roughly round in about thirty seconds), shavings, drawknife, cat, and Rayburn.


I'm very happy with the way it turned out. It actually works better than I expected, because it automatically clamps the work harder as you pull on it with the knife, meaning you don't have to apply much force at all to hold the work securely.

Comments

Looks like the cat is an essential part of the workings. I notice you don't describe its function in shaping the pegs... slight omission perhaps?
The cat functions as a critic, ensuring the operator takes more care. Nothing worse than looking slipshod in front of a cat.
Ahhh, management.

Or supervisor.
Yes, I was just thinking a video might help. You sit astride the shave horse and shave slivers of wood off the work by drawing the knife towards you, like in the second-to-last photo. Pushing the bottom of the pivoted section with your feet makes it clamp the work tightly; pulling your feet back releases it so you can turn the work and shave off a different part. The height of the table under the work is adjustable to enable you to clamp different thicknesses of wood by moving a wedge. The knife can split thick chunks of wood off or shave away fine slivers depending on how you hold it, so you can quickly hack out the rough shape and then finesse it using the same tool.
Wibble pointed out that I completely misunderstood what you were asking. Bosch's function is to collect shavings on his head and complain that there isn't anywhere near enough tuna used in the making of wooden pegs.
This is cool, and I love how you come up with things like this.
Fabulous!! You should have your own TV show, I'd watch! Love the critical cat too ;)
I reckon he was actually criticising the building work going on outside the back door. "There's not enough fall on that drainpipe," I heard him purr.
Two points which may be of interest.
1, the hole offset in the tenon is deliberate as one of the functions of the peg is to draw the joint tight and to keep it tight as the wood ries out over the years.
2, the line of the grain of the shave peg should run perpendicular to the grain of the beam. what I mean by this is that the grain runs vertically in the post and lengthways down the peg BUT the growth rings in the peg should be aligned horizontally. The reason for this is that the peg, as it dries, shrinks slightly more across the growth rings than along them and so becomes slightly oval with the long axis of the oval running horizontally while the long axis of the oval of the hole runs vertically.

In this way as the timber dries out the 'ovalling' of peg and hole act to increase the rigidity of the joint.
In the case of the joint in the top photo the outer mortice hole had worn larger than the tenon hole so it took a bit of careful work with a small round rasp and the shaping of the peg to make it possible for the peg to pull the tenon in tight, which it seemed to do successfully because the joint was wobbly before the re-pegging and rock solid after.

I hadn't realised about the pegs going oval as they dry but it makes sense. I'll have to mention it to the joiners who will be assembling the frame. The posts and beams will be green oak but the plan is to make the pegs from air dried oak, so the pegs should shrink less than the holes (I think) and become tighter as they age. The pegs I've already done for the ancient frame were made from offcuts of kiln dried oak, so they hopefully shouldn't shrink at all.
The drying/ovalling of holes and pegs is the way the old bodgers made chair that survive without modern wood adhesives. That TV series on old craft skills missed a whole lot of minor but vital things - mainly I suppose as it would be somewhat esoteric for a mass audience.
It's just occurred to me that the tenon grain is perpendicular to the mortice grain, so the holes will go oval in opposite directions. Do we want the peg to go oval in the same direction as the mortice hole or the tenon hole? The former would seem to produce a more weather-tight result.
the joint is weather tight (so long as it was a good fit initially) what you re doing is arranging the structure such that instead of (or as well as) relying on a big mallet to force the pegs home. As the wood moves the peg automatically tightens the joint. If the grain runs vertically and the grain (growth rings)of the pegs line up you're relying on the peg being significantly drier (and so moving less) than the bulk timber around the hole.

In practice the pegs used in bulk construction tend to be hammered home with little regard to the direction of alignment of the growth rings. The result is that occasionally over the years odd pegs can become loosened on the holes*. At which point a swift clout with a good mallet is called for. Or fit a replacement.

*At this point it may become possible to extract the peg without the use of tools - see Dorethy L Sayers The Nine Tailors for a fictional example.

Using dried pegs and green joists is normally sufficient to ensure the joints remain tight.

Timber frame construction is done in such a way that the joints are under compression with lateral forces spread throughout the whole joint. So a loose peg is not a critical failure.