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The Use of Framing Pins and Offset Prickers in RWT

 
pollinator
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I came across some advice to get a hold of podgers (framing pins) for RWT. I get that they hold the joint together until the final dowel is hammered, but I'm unclear in what order of events they are needed.

My understanding is that you chisel out the tenon & mortise -> drill a 25mm hole through one of the two (does it matter which one?) -> using the pricker mark the center 3/16" closer to the shoulder on the second log -> drill a hole through that -> nail in the podger. If that's correct, when do you remove the podger to replace with the final peg?

Am I correct in thinking that these are 'nice to haves' vs 'must haves'? Are belt straps still needed if the junction is held via a podger? Lastly, and how many would I need for a small build, could I get by cycling through with 2 or 3?
 
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For sequence, you would drill out the mortise peg holes first, then assemble and mark the location on the tenon, remove and offset the mark and drill the tenon. Reassemble the joint and insert the pin to hold the members temporarily if needed.

The peg size can vary depending on the size of your members. Ben Law seems to use two 5/8" (about 15mm) pegs rather than one 1" (25mm) one. Your whole frame is relatively small compared to common barn-sized frames, and the members you use may be smaller too.

I think these podgers would be a nice-to-have, and you could easily make something like them yourself simply by shaving down regular pegs so they are a slide fit and easy to remove rather than a force fit like you want for permanent pegs. I know more about historical timber framing than the practicing timber framer's terminology and hadn't heard the terms "podger" and "belt strap" before. I would think podgers and belt straps are something of an either/or case. Maybe belt straps are good for holding parts together before holes are marked and drilled.
 
Maruf Miliunas
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Good to know the order matters, thanks for clarifying.

As for peg sizes, Ben uses both, depending on the type of joint. The wind brace get two 5/8" pins whereas the major joints like the crucks get a single 1". I'm having trouble finding a 5/8" dowel maker, hence I'm wondering if I could reduce the size of the dowels and increase the number of pegs.

Here's the write up of the framing pins if it adds any clarity, as well as the link:

A temporary pin for use in traditional pegged timber frame building. The pin is used in place of the oak peg during construction and assembly of the frame.

Forged from solid stainless or mild steel bar, and ground to a smooth finish, with a T-handle (useful for knocking out wooden pegs!).

Stainless pins are recommended for green oak that is likely to be getting wet while the pins are in place, as mild steel, water and the oak's tannin will stain the wood.



My question is, why would a framing pin be necessary in the first place, versus pegging in the oak dowel before raising the crucks for example? As for the belt straps, I imagine it's for peace of mind as well, knowing they won't budge on their way up, or if something happens and they fall down.
 
Glenn Herbert
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For extra strength while raising a bent assembled on the ground, I could see the usefulness of belt straps. The pegged joints might get much more stress if raising is at all uneven than they would see in place.
 
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I have also never heard of these two items, and they seem to me to be a solution in search of a problem. I agree with just using wooden pegs. They can always be removed easily as long as you don't trim them. They can be drifted out, or if time is of the essence, often the claws of a claw hammer can be driven into the side of one and it levered out. I guess if a person wanted to get fancy, one could cut a branch and have a natural T-handle on on a wooden bodger, but I don't really see the point unless something were to be assembled and taken apart multiple times for some reason.

The offset prickers look to me like something to cost money and constantly have to keep track of and not lose. I don't really see an advantage to them. To expand upon Glenn's description, after the mortise and tenon are finished, the tenon is removed from the mortise, and the pin hole drilled through the piece with the mortise. The tenon is then seated in the mortise, and the same auger just used to bore the hole is inserted into the hole and pressed against the tenon and given just a turn or two for the screw to slightly mark the surface of the tenon. The tenon is removed and the auger's screw is placed next to the mark it just made (make sure to place it on the appropriate side), and the hole is drilled. I don't really see the advantage of an extra tool, especially at those prices. Although, if those are the going prices for those tools, perhaps I should be making them and singing their praises as well! Something else I just thought of: the wooden pins flex and take the shape of the offset, locking the joint in place. I wonder if an unyielding steel pin might damage the tenon, possibly even splitting it?
 
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Jordan Holland wrote:Something else I just thought of: the wooden pins flex and take the shape of the offset, locking the joint in place. I wonder if an unyielding steel pin might damage the tenon, possibly even splitting it?



I think the taper of the steel framing pin allows it to take up the difference between the offset holes without being driven any tighter than necessary to pull the joint tight, then the T-handle allows it to be removed by twisting and pulling rather than drifting out. If the work is done in a shop, it will be together and apart at least once to fit it and move it to the site, repeat inserting/removing wooden dowels and I can see a savings in time and materials.
Some of the photos I just viewed of a raising had a mix of dowelled joints, framing pins, and not-yet-dowelled joints. Whether it's leaving some freedom of movement for fitting parts during the raising, or effective use of labor to get the lifting done NOW and get the pegging done later... I'm sure there's a lot left up to personal preference.
 
Jordan Holland
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Kenneth Elwell wrote:

Jordan Holland wrote:Something else I just thought of: the wooden pins flex and take the shape of the offset, locking the joint in place. I wonder if an unyielding steel pin might damage the tenon, possibly even splitting it?



I think the taper of the steel framing pin allows it to take up the difference between the offset holes without being driven any tighter than necessary to pull the joint tight, then the T-handle allows it to be removed by twisting and pulling rather than drifting out. If the work is done in a shop, it will be together and apart at least once to fit it and move it to the site, repeat inserting/removing wooden dowels and I can see a savings in time and materials.
Some of the photos I just viewed of a raising had a mix of dowelled joints, framing pins, and not-yet-dowelled joints. Whether it's leaving some freedom of movement for fitting parts during the raising, or effective use of labor to get the lifting done NOW and get the pegging done later... I'm sure there's a lot left up to personal preference.



I agree with this when it's just laying there on the ground, but I was wondering about the moving process. Even if the pins are slightly undersized, I wondered if the forces created while flexing could be enough to damage it. I've always considered the pins to be the final step. I would not use pins in a shop myself.
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