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View Full Version : Thickness sander or ???



Michael Stafford
02-04-2005, 9:29 AM
In some respects this post could also be in the turning section but because it deals with tooling more than turning I will put it here.

In segmented turning you have to construct rings of segments and glue them together. The pieces are held together during the gluing process with tape and band clamps/hose clamps.

Inevitably after the glue cures there is a certain amount of enevenness/lack of flatness that has to be corrected before the ring is ready for assembly.

I have been flattening my rings in three ways. One is to use a router planing jig. It works very well, gives a very flat surface that is smooth and excellent for gluing to the rest of the segmented assembly. The main drawback is that it is terribly slow to adjust and position everything and make the multiple passes needed for compound mitered rings.

The second method I am using is a safety planer in the drill press. I am a little fearful of this safety planer. I have to try to hold down the ring flat to the table, the rings are occasionally bowed a little, and push it through this whirling disc of steel with sharp blades on its circumference.

The third method is to hold the ring in Cole jaws or by Cole jaws and turn one side flat. This works but is the most dangerous to the assembled ring.

I have considered buying a Performax 10-20 sander to use for this task. A larger version like the 16-32 would be better but I have no space for the larger tool. I need the portability of the smaller version and the largest rings I have to deal with are about 10 inches in diameter.

So all you wise wizards of woodworking, have you any experience with this tool? Is it too much of a hobbyist tool to be used as described? What are the drawbacks to this method? Will it be dangerous to my glued up rings? I have not had any losses with either the router or safety planer method. I have heard that other segmented turners use this method but do not actually know but one that does and he is too far away to visit and see the process he uses.

Your thoughts appreciated.

Ken Salisbury
02-04-2005, 11:26 AM
Mike,

I have made many segmented and layered bowls without the problem you are describing (flatness of rings). I assemble the rings and stack them in the manner show in This SMC Article (http://www.sawmillcreek.org/articles/4/) . If you perform the ring glue-ups on a flat surface (I use a metal rollaround table (cart) which works fine. If your segments are accurately cut they can be glued together with only slight hand pressure for a few seconds for the glue to sorta grap. Then allowing individual pieces of 2's, then 4's and so on until the ring is complete. As you can see in the photos I do not clamp around the diameter of the rings until I have completed 2 halves of the circle as shown in the first 4 photos in the "Process" section of the Article

Having said that, if your process still results in "non-flat" rings then the solution would be to use a drum sander to provide the flatness required. (p.s. - you use the term "thickness sander" and I do not know of such a machine. I assume you mean a drum "finishing" sander)

Michael Stafford
02-04-2005, 11:38 AM
Thanks Ken, for your response. Yes, you are correct, I do mean drum sander. Big words always throw me for a loop. I occasionally have some flatness issues with flat mitered rings but my primary interest is in getting a flat surface on compound mitered rings that are glued to rings that have been flattened on the lathe. I have read your article several times and have learned much from it. I am using a slightly different technique that uses both flat and compound mitered rings. Thanks for the help.

I use the same technique for compound mitered segments - again it really comes down to the accuracy that you can cut the individual segments. Some times If I have a problem with an indiviual ring I will get 1 side flat, assemble it to the bowl, turn it flat on the other side and then continue the ring build-ups to the bowl. If you look closely at picture #17 in the article you will notice several of the rings had some prliminary turning on the lathe. The blank as shown in that picture had been on and off the lathe several times through the turning process. Good Luck ! !

p.s. bowl shown sold for $175.00