Walnut Bowl – Making a Longworth Chuck

The Google thing worked for me like usual, I came up with a couple of options, a Cole chuck or a Longworth chuck. Our initial conversations in the wood shop were to keep it simple and inexpensive, so we initially excluded the Longworth style because of the more complex curves. Well I think we were wrong, shhh don’t tell our spouses or kids. The Longworth isn’t difficult to build, will certainly work for what I need, and will be a great addition to the shop. I found a couple of videos Longworth Chuck English by Henrique Sampaio and Make a Lonworth Chuck Pt1 by Woodcraft of Spokane. The second link is the first of 4 parts, and goes into much more detail, the first is a great overview and huge.

Longworth Chuck Notes
Longworth Chuck Notes

This is a bit of tangent from the Walnut Bowl project, as if tangents are abnormal for me…squirrel…oh shinny! For those of you that have seen the squirrel team in action at Gulf Wars, quit laughing! Some good grade plywood, stove bolts, wing nuts, screws, washers, a face place, and some rubber stoppers should get us started. Much of this we have laying around the shop, as you probably do also. Although the rubber stoppers are a bit odd to have just laying around so I’ll have to order some online.

I took some notes from the videos, this should help a bit and not have me running back to the computer all the time. My apologies, the notes are for my reading, I wasn’t originally planning to post them, but I thought they might be useful for others. Maybe chicken scratching would be a more appropriate term. While I could write out the steps that I took, I suggest just watching the videos, its really not that difficult.

I happen to have some 3/4″ Baltic birch triangles laying around. Yah don’t ask, lets just say they showed up in my truck one day after work a while back. That should make some great material for the base. As we are making a medium to largish sized one, we are going to have 4 long and 4 short arches to leave a bit more material in the center.

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All but the arcs drawn in at this stage. Circles from the inside out, face plate, minimum inside dimension for 4 longer arcs, minimum inside dimension for 4 shorter arcs, center for arch radius, maximum outside dimension, outside edge of chuck.
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Here you can see the arcs drawn in and where they terminate. The outside has been roughed on the band saw and cleaned up with the router using the circle jig.

Hey Rhydderch, see I do listen most of the time in your Geometry for Woodworkers class! The layout was done with a straight edge and a compass, with minimal measuring. Its still not complete, but it’s a good ways into the process and has been a lot of fun researching and laying it out. Next time we work on cutting the arcs with the router and drilling the finger tightening holes.