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Justin Credible
Joined: Sun Apr 29, 2012 11:33 am Posts: 2
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 Compound cut segmented bowl blanks!
Okay...so my "mentor" and I were talking the other day and he said that he wanted to make an "open" bowl (bowl that progressively slants outward making the top wider than the bottom) but do so with wood no thicker than 3/4. We both spent a fair amount of time trying to determine the compound angles that would make this possible. Since I searched seemingly everywhere online with no results, I thought I would post the solution to cutting these somewhere. Once it dawned on me that this is actually just like cutting crown moulding, I decided to do just that and cut it like crown moulding. I can now make a bowl with an infinite amount of slope or slant, difference between the bottom circumference and top circumference, using only 3/4" wood and two small pieces of scrap cut at the angle I want my compound cut on. These pics are basically just scrap wood for demonstration. Now that I figured out a way of doing it, I will be making real bowls and will post once complete. Pieces of scrap cut at your desired angle act as a jig to hold workpiece for your cuts.  You then simply begin making your cuts the same as you would a normal segmented bowl, make a cut, flip your board, make another cut etc. the only thing different is you are resting your workpiece on the angled scraps you cut. these are the first 3 that I made using this technique. Obviously scrap wood and thrown together but you get the idea.   
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| Sun Apr 29, 2012 12:02 pm |
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cattzap
Joined: Thu Jan 05, 2012 9:48 am Posts: 55 Location: Carlos, Tx
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 Re: Compound cut segmented bowl blanks!
It would be a ton easier if you built a sled with a hold down for your tablesaw.
_________________ Old as the hills Craftsman lathe (it's better than not having anything) Woodworking for 35 years Built about everything there is to build, except for anything round Carlos, Tx
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| Mon Apr 30, 2012 6:48 am |
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Justin Credible
Joined: Sun Apr 29, 2012 11:33 am Posts: 2
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 Re: Compound cut segmented bowl blanks!
Im all for building sleds, jigs, rigs, and so forth...but I cannot see where building a sled with clamps to hold your workpiece down at the compound angle is a "ton easier" than just cutting two pieces of scrap at your desired angle. to each his own but Im pretty sure doing that would required the same two pieces of scrap I use....plus another two hours work...for the same exact result.
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| Mon Apr 30, 2012 10:04 am |
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cattzap
Joined: Thu Jan 05, 2012 9:48 am Posts: 55 Location: Carlos, Tx
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 Re: Compound cut segmented bowl blanks!
Have you ever seen the little thumb clamps Harbor Freight sells for $5? A quick flip down and it's held, and anoter quick flip and it's released. You can easily cut 1000 pieces an hour with it.
_________________ Old as the hills Craftsman lathe (it's better than not having anything) Woodworking for 35 years Built about everything there is to build, except for anything round Carlos, Tx
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| Mon Apr 30, 2012 2:01 pm |
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BPCR4570
Joined: Thu Mar 24, 2005 7:48 pm Posts: 531 Location: DFW, Texas USA
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 Re: Compound cut segmented bowl blanks!
Cool idea. I like this. Maybe I'll try it next time. I just got through cutting a bunch of segments for a project I hope to share on here in the not too distant future.
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| Tue May 01, 2012 12:04 pm |
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owlelope
Joined: Wed Oct 28, 2009 9:50 pm Posts: 3
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 Re: Compound cut segmented bowl blanks!
I like what you did. How do you do the bottoms for the bowls?
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| Tue May 01, 2012 8:30 pm |
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cattzap
Joined: Thu Jan 05, 2012 9:48 am Posts: 55 Location: Carlos, Tx
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 Re: Compound cut segmented bowl blanks!
I'm curious, with the shape of it all put together, how are you clamping it to glue it? And don't misunderstand my above comments. I like what your doing with this. There's just more than one way to skin a cat sometimes. I have a compound miter saw that will cut this with it sitting flat. I also just noticed that you do too, so you don't even need to make the setup you've got. Tilt the blade in both directions, cut one end of all your parts, tilt it the other way with a stop and cut all the other ends.
_________________ Old as the hills Craftsman lathe (it's better than not having anything) Woodworking for 35 years Built about everything there is to build, except for anything round Carlos, Tx
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| Wed May 02, 2012 6:41 am |
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MrRules
Joined: Sun Dec 02, 2007 5:13 pm Posts: 69 Location: Streetman, Texas
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 Re: Compound cut segmented bowl blanks!
Have you ever tried the "bowl from a board" procedure? You can get the same shape without having to make the compound cuts and the difficulty in the glue up. Just do a search on You Tube for the "Bowl from a board" concept and you will get several ideas.
Stu
_________________ MrRules
Woodturner in Training
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| Sun May 13, 2012 10:28 am |
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TomD
Joined: Sat May 29, 2010 10:58 pm Posts: 14
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 Re: Compound cut segmented bowl blanks!
You can make your bowl blanks your way or cut the angles with the wood flat using a compound angle. However you must make one change in your method. Your glue joints will be end grain to end grain the weakest joint of all glue joints, which could get very dicey if you turn a thin bowl with end grain joints, therefor align your grain to radiate out from the center of the bowl and you will have side grain to side grain glue joints the strongest glue joint. Also a grain that runs around the bowl will expand into the center, unless you use a very loose or floating bottom the bowl will pull and push it's self apart. This also will be remedied by having the grain radiate out from the center since wood expands very little along it's length of grain.
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| Tue Jun 12, 2012 12:53 am |
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