segmented ring question?

[Quinn McCarthy]

I am making a 72 piece 6.5" segmented ring. I have got the pieces cut and when I put a hose clamp around it and tighten it up I get distorting to the ring. It gets oblong. I was going to do the glue up just like Curt Theobald shows in his DVD using tape to hold the pieces together. THe question I have is would I be better off gluing the pieces together in 2's and then 4's to make a glued up section and then gluing the 4 piece sections together the normal way?

Or maybe there is a better way to glue the ring together.

Thanks much.

Quinn

[Paul Engle]

Quinn,
gluing by two's , then two's up to halves , then the halves, allows you to control out of round, us a template on butcher paper or wax paper to keep from sticking ,to check each of the two's up to the halves. Also, get Malcolm Tibbets book on segemts ... he be the man.

[Quinn McCarthy]

Thanks Paul

I will take your advice and give it a try.

Quinn

[Brodie Brickey]

I have to second Paul's advice about Malcolm Tibbet's book. He makes it very straight forward.

[Robert McGowen]

I am making a 72 piece 6.5" segmented ring.

My segmented software shows an outside segment length of 9/32" for each segment for a 72 segment ring 6.5" in diameter!

I have had really good results with rubbing two pieces together for about 3 to 4 seconds and just letting them sit there without any tape, clamp, whatever. (This is also in Malcom's book) Make sure all surfaces have glue on them and they will stick right together. Be aware that with some rings, you can't just glue two together and then halves until you get a circle. Take 10 segments for example. You end up with 5 pairs, then 2 sets of 4 and 1 set of 2, then 1 set of 6 and 1 set of 4. Hard to put halves together that way! (Yes, I know this from experience. :) )

[Quinn McCarthy]

I have the Malcolm Tibbets book.

I was hoping to save some time by doing it all at once like Curt does but with this many pieces it will be tough.

My software says 9/32 as well.

My plan is to take this ring which is 1" high and split it into 3 rings 1/4" tall. Then surfacing the rings dow to 1/8" and gluing them back together offset by 1/2 segment. It is an alternating color ring so it will look pretty cool. I got that from the production turning section from Malcolm's book.

Thanks for all of the advice.

Q

[Bill Wyko]

I have found that sanding 1/2 rings will also give you an egg shape sometimes. I'd make 1/4 rings and mock them up to see if one half is longer than the other, then make the 1/2 rings with the longer sides and sand them parallel until the ring is round. IMHO. Is there 72 segments? If so that would be very difficult to cut 2-1/2 degree miters accurately. What are you using to make your cuts? There's one other problem you might run into. That is when you sand the rings, the ones you sand are now smaller than the rest so you might want to make an alignment mark so the sanded segments align when you do your glue up of the rings. These ar little things I've had issues with on a few pieces. Good luck.

[Quinn McCarthy]

Bill

Yes there are 72 segments.

I like your idea of checking first with 1/4 ring. THat way I can sand a little bit in 4 spots rather than just 2.

I have a sanding jig for my disc sander. I cut the pieces on my miter box and trued them up on the disc sander. I made a 72 segments sled. It is very close to being right. I made a practice ring and used that to calibrate the jig. Although I had the same problem there I had some distortion from the band clamp.

Thanks

Quinn

[Bill Wyko]

If I can be of any help please feel free to ask.

[joe greiner]

I'm not very adept at cutting perfect miter angles. And this might not be a very sophisticated way of doing it; also somewhat tedious.

I cut the pieces long without regard to miter angles, and lay out on a slightly oversize waste pattern, stacked up-and-down like those popsicle-stick assemblies and taped down. Then cut along the miter line with a bandsaw or scroll saw. The constant-width kerf assures both sides are parallel even if the "miter" is slightly curved, and they fit together perfectly (or close enough).

I first saw a variation of this trick used by Nawm (Abrams, NYW) for getting perfect miters on picture frames. Some corner clamps have a gap to accept a back saw for the refining cut.

Joe

[Quinn McCarthy]

Thanks everyone for all of your advice.

I finally got it done. It took 2 tries I have to admit.

The ring is Jarrah and hard maple. NOw I hope I don't mess it up when I split it into 3 rings.

Thanks

Quinn

[Robert McGowen]

Looks like it will turn out very nice. I had to laugh when I read your earlier posts and you used the words "72 pieces" and "production turning" in the same thread. :eek::eek::eek:

[Bill Wyko]

Man and I thought 24 segments was difficult.:eek: