Dowell Sleeves?

[Joe Wood]

I glue up these moon gates using nine 1/4 x 4 x 20' long laminations, clamping them off to these 1/2" dowels I've drilled in to the top of the round table jig's wooden edges.

these wood dowels aren't the most stable places to clamp off to, so I was wondering, are there metal sleeves I can inset 3" into the table, then insert the wood or even metal dowels in to the sleeves? These would be a lot more 'fixed' in place then the wood dowels alone.

If there is such a thing, what would these sleeves be called, and where could I get them?

[William Lessenberry]

Iron pipe of the diameter you need cut to length and inserted into the holes.
BillL

[Kevin Jenness]

Have you looked in McMaster Carr for steel sleeves, bushings or dowel pins? Generally speaking, if they don't have it, you don't need it.

In employment we had several dozen oak T-shaped clamping stations about 2" x 2" x 6" on each leg half-lapped together that were screwed down to a baseplate or benchtop. An advantage of the T shape was that we could clamp from below as well as above the layup.

You might be able to find ready-made steel angle L-brackets for the same purpose or you could have a metal fab shop punch, notch, bend and weld 2" steel angle. Seems like it would be tough to clamp to round pins without the clamps trying to roll or slip off.

[Rich Engelhardt]

Would Con-duit?

[Kent A Bathurst]

Have you looked in McMaster Carr.......

Yep. Look for spacers.

for example, 1/2" ID; 1"OD; 2" long; Nylon; 10 pc for $21

I don't know what size you're looking for - I just grabbed that size as an example.

Nylon
Aluminum
Stainless 18-8
Stainless 316
Zinc plated steel
Zinc plated brass
..and more


As Kevin said, if they ain't got it you don't need it

Really cool gate, by the way!!

[Kevin Jenness]

Yes, nice gate. What adhesive are you using?

[Joe Wood]

Yeah we've built quite a few moon gates and usually use Titebond III. Springback's not too bad.

here are some more, you can see how we used to wrap the lams around the outside of the jig, but the crate for those was a little too wide for shipping so that's why I reduced the radius a bit and am clamping on top of the round table jig now https://www.facebook.com/media/set/?set=a.10156374782932044&type=3

[Kevin Jenness]

If you are using a certain radius repeatedly, why not cut down your table and clamping flanges to suit? The continuous backing given by your original setup combined with a caul on the outside should result in a more consistent glueline thickness (perhaps that is not an issue) and would be simpler. The brackets I mentioned are more adaptable for custom work.

[Bill Dufour]

Threaded insert. then a long bolt into each one. just enough thread to go down flush.
BillD

[Malcolm McLeod]

If there is such a thing, what would these sleeves be called, and where could I get them?

From your description I think you are looking for “mold leader pins & bushings”. They come in a wide variety of sizes & lengths, and should last forever in your application.

One source:
https://www.choicemold.com/product-category/leader-pins-bushings/

[Cary Falk]

If you are using a certain radius repeatedly, why not cut down your table and clamping flanges to suit? The continuous backing given by your original setup combined with a caul on the outside should result in a more consistent glueline thickness (perhaps that is not an issue) and would be simpler. The brackets I mentioned are more adaptable for custom work.

This seems like the best option to me. I think you would get a more consistent circle and the ability to clamp anywhere if the wood does not coorporate.

[Doug Garson]

Beautiful gates, why are you using round dowels for the jig? Why not use blocks of wood, curved on the outside to match the curve you want and screw down to the jig with wood screws or with threaded inserts and bolts?

[Robert M Richardson]

On McMaster Carr's site search for drill bushings. They are normally used on jigs to drill holes precisely on multiple parts on manual drill presses. CR steel rod will fit nicely in them.

[Cameron Wood]

I just screw 2x4 blocks to a sheet of plywood, usually for the inside radius. Allow for a liner piece if needed.
Only takes a few minutes to strike the line and fasten the blocks, and as long to change to a different curve.
Blocks spaced as needed- wider for gentle curves, closer for tight ones.

[Richard Coers]

No matter what you put a 1/2" dowel in, it's still going to be flexible. Up the dowel size and add more structure.

[Brian Runau]

Proves you can't have to many clamps.

[Tom Bender]

Make another arc with some less beautiful stock. Suck it in a little and glue it down to the table. Maybe add a few 4" high glue blocks. You now have a form you can clamp to without any dowels. Installing the glue blocks first will help you position the form to glue it down.

[Joe Wood]

Yeah this customer decided against a moon so I have time now to get a better plan in place.