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View Full Version : small gaps in segmented ring — how to fill



Dan Gaylin
11-11-2019, 11:21 PM
Hi all,

I am continuing my learning experience with segmented bowls. I have some segmented rings that are nearly excellent but have one or two segments with partial gaps. I glued the segments together using Titebond 2 and used a hose clamp to clamp them together while it dried.

So my question is what glue should I use to fill the very slight gaps that are only on the outer face of the ring? I am thinking of using thick CA glue but would appreciate any advice.

Thanks,

-Dan

Brice Rogers
11-12-2019, 12:27 AM
I've filled gaps with CA, epoxy and PVA glue. They all work. I will fill/color with sawdust, wood flour, enamel, transtint, coffee grounds, glitter.

If you packed the gaps with something like fine sawdust or coffee grounds and then drizzled CA over it, it could work. But I'd wonder if you would be wiser to use medium CA so that it will penetrate into the gaps. I'd suspect that the thick CA might lay on the surface.

Steve Eure
11-12-2019, 6:37 AM
First, your rings are not perfect. The best and easiest way is to glue up half rings, ie(if a 12 ring segment, glue up 6). When they are glued together, put them in your hose clamp and put a dowel between each side that doesn't have the glue. Compress them with clamp. When dry, take each half to a disc sander or any flat sanding surface and sand them flat. Keep checking for flatness. It usually doesn't take too much. Then when no gaps are present, glue the two segments together. Not hard. If my instructions are not understandable, go to the internet and find a video on how to do it. It really is simple.

John Beaver
11-12-2019, 11:35 AM
Brice's suggestions will work fine for filling, but it would be better to make the rings correctly. Keep practicing. It makes the piece so much better when the joints are correct.

Dan Gaylin
11-12-2019, 1:33 PM
Thanks, folks, for your responses.

Brice: I think medium CA glue with some of the sawdust makes sense. These are really tiny partial gaps so I will use a very narrow syringe to inject it in there. I'm hoping that when the ring is turned a bit thinner, they won't even be there.

Steve: I had heard of the half ring approach but all of the videos I've seen people do full rings...I will do another search.

John: Indeed I agree with you. I'm not really sure what I did wrong here, and the rings are close to perfect but of course close is not really good enough. The angles and lengths all seemed perfect. It may be that cutting them on the band saw with a blade with a fairly low tooth count is what introduced the little imperfections. It's also possible that I didn't rip the longer pieces perfectly the same: the segments that have the very tiny gaps are slightly taller than the others......? :-(

Chris A Lawrence
11-12-2019, 5:09 PM
Turn it down first then deal with any remaining gaps. I put a drop of thin ca glue in the gap then sand with 220 grit paper to work saw dust into the gap. If its big enough to get a finger nail in it may take a couple rounds to fill it in. Doing it this way you get a pretty close match to the color and can make most gaps vanish.

Sam Force
11-12-2019, 7:29 PM
Make a "wedgie sled" for your bandsaw. Then mark and glue your segments as per Jerry Bennett's recommendations

Eugene Dixon
11-12-2019, 7:40 PM
Check out Earl's sanding jig somewhere buried in his videos: https://www.youtube.com/channel/UCQIa3_CjaqYnmfAixgt6kGA

Dan Gaylin
11-13-2019, 8:36 AM
This is all very helpful thank you. I have a jig for the bandsaw that makes the lengths the same and the angles precise. But it was my first go with it and it needs some improvements.

Randy Heinemann
11-13-2019, 1:44 PM
I will admit I know very little about segmented bowls, but I sincerely doubt that using a bandsaw to cut the segments to length would be accurate enough to avoid gaps between segments. All it would take is an extremely tiny difference from the intended angle or length and that would accumulate over all the segments to produce at least 1 gap on each ring. I've never known a bandsaw to cut clean enough to avoid missing the intended angle or length. Even with a fine blade there is always some flex in the bandsaw blade just by its very design. I would think that the table saw with a high quality blade with a high number of teeth would be the best tool for the job along with a sled or jig which guaranteed the desired angle and length. I could be wrong about the bandsaw, but I'm just going with my experience with bandsaws versus table saws.

roger wiegand
11-13-2019, 6:59 PM
I don't do segmented bowls, but have had quire a few occasions to make circles for frames and such. I use the make two halves, joint and then glue the two halves together method. If I had a gap I'd cut the ring in half and then re-glue. Not much looks worse than filled or unfilled gaps in a segmented turning.

I've cut my segments on a SCMS (yes, I know that's "impossible") or on the table saw using a jig. A plane and shooting board can get the angles dead on (since I finally learned to sharpen a plane this has become my method of choice).

I've seen sliding tables for bandsaws with micrometer adjustments at turning shows that appear to be pretty slick, but for a kilobuck they ought to be. They use a high tooth count blade that produces an OK glue quality surface and machined jigs that hit the angles exactly.

Dan Gaylin
11-23-2019, 12:19 PM
Folks,

thanks for the additional responses. I suspect the bandsaw as well. I have a very precise way of measuring the angle but I am not sure the saw, with its 13” throat can stay all that precise. What about a miter saw? I am a relative novice of a woodworker and using the table saw to cut small parts makes me nervous. I mostly only use mine for ripping medium sized pieces. I use a track saw, miter saw, and band saw a lot more. I am much more comfortable with a miter saw than a table saw.

Ted Reischl
11-24-2019, 8:26 PM
A wedgie sled is the way to go. If you have a friend with a cnc router he can make you one and save you a bunch of bucks.

Peter White
11-24-2019, 8:47 PM
If you make a wedgie sled zero insert and zero ramp for segments to fall away.Then you need a good wedge with correct angles to set
your fences.I can cut 60 segments and all fit with no gaps.Check out Jerry Bennett at Seg-Easy for plans for the sled on the table saw and wedgies.

Dan Gaylin
11-25-2019, 4:18 PM
Thanks, Sam, Ted and Peter for the wedgie sled suggestion. Will this work on a small contractor table saw? I am happy to report that the piece I was working on turned out pretty nice. The gaps ended up not being noticeable once I had turned the piece to size. This is about a 12" diameter bowl, which is as large as my midi lathe will go. Pics below:

420293 420295

Chris A Lawrence
11-25-2019, 5:56 PM
If it has a miter slot a sled will work. I started out with a cheap ryobi table saw from the big box store. Just make sure the sled is square with the blade.

Guy Donham
12-02-2019, 1:49 AM
First off you need to adjust your sled to not get gaps. I recently bought the Wedgies and made a two fence sled and it makes perfect rings. Before I got the Wedgies I used to glue up half a ring at a time and made a jig that I would square the half ring ends up and then glue the two halfs together. I made a sled with a clamp to hold the half rings in place while using the table saw to square the edge. This would work as a stop gap but you need to fix your sled to get more perfect rings to start with. The gaps can be filled but will stick out like a sore thumb. Sometimes you just have to drop a project in the trash and start over and make it right from the beginning.