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Best saw type for cutting accurate bevels for triangles?

4.1K views 16 replies 12 participants last post by  TravisH  
#1 · (Edited by Moderator)
New to woodworking here and I have my first intricate wood project in mind that I want to see come to life. The plan is to make a geodesic dome out of small triangles (for those familiar it's going to be a 2v dome), my issue is finding the best way/easiest way to cut the bevels on the triangles accurately so they can fit together as seamlessly as possible. My thought process would be to cut 3/4" wood into the size of triangles I need, then bevel the sides to the angles I need ( roughly 15.86 degrees and 18 degrees). Throughout my research, both table and miter saws have their pros and cons for cutting bevels and both would require me to build a jig to hold the triangles in place and to aline the triangle side parallel to the blade. My main goal is to cut the bevel in a way where it doesn't take any wood from the face of the triangle ( to eliminate any gaps when putting the dome together), so accuracy would be key and I know I will have to practice to get that down. The reason I ask what saw would be best is because I've watched plenty of videos where people just "work with whatever saw they have" or just have both saws, and since I don't currently have either and I can only choose one, I want to find the one that would be best for cutting the bevels accurately (because that's going to be the hardest part).

Any suggestions help, that includes; videos of jigs for triangles, types of blades for crisp cuts, suggested measuring tools for angles (protractors, angle finders etc…), and of course, what saw would be best for bevels.

I definitely wouldn't rule out hand saws with jigs. I do have a Japanese pull saw that I've used and it produced some pretty clean cuts (which is something I need for this project), I just know it will a lot more time consuming for 40+ triangles and roughly 120 bevels that would need to be hand cut. But if that's the best route I would also take suggestions for that and what would be that best way to go about that.
 
#2 · (Edited by Moderator)
I think I know what your thinking and it's plan full of treachery. I once helped a student from the Art institute out here in California make up one in acrylic.
We used my table saw with lots of on the fly fixtures. It was very difficult with lots of flying exploding small pieces.
It one of those things that's a great idea but difficult to accomplish.
If your assignment is going to be wood consider a large block of basswood and grind away the wood reveling your design.

Good Luck
 
#3 ·
I think I know what your thinking and it's plan full of treachery. I once helped a student from the Art institute out here in California make up one in acrylic.
We used my table saw with lots of on the fly fixtures. It was very difficult with lots of flying exploding small pieces.
It one of those things that's a great idea but difficult to accomplish.
If your assignment is going to be wood consider a large block of basswood and grind away the wood reveling your design.

Good Luck

- Aj2
+1 but when there is a will there be a way,good luck.
 
#4 ·
We probably need more information. What is the dome going to be used for and how big is this dome going to be? In general a table saw will usually be more precise than a miter saw.

For small domes and spheres, you might look at Steve Garrison's videos on making polyhedrons. I don't think he uses triangles in any of them but he shows some very precise techniques he uses for cutting the pieces on the table saw.
 
#6 ·
We probably need more information. What is the dome going to be used for and how big is this dome going to be? In general a table saw will usually be more precise than a miter saw.

For small domes and spheres, you might look at Steve Garrison s videos on making polyhedrons. I don t think he uses triangles in any of them but he shows some very precise techniques he uses for cutting the pieces on the table saw.

- Lazyman
The general idea is to create my own "hidden globe bar". So I would need to create two 2v geodesic domes that would (in theory) fit together smoothly, and then create the arm and hinge that will open the top dome and attach it all to a couple of slabs. I haven't gone too in-depth with the whole thing because I want to make sure the domes are possible first. The diameter would look to be roughly 2 feet. I need it large enough so I can create a basket in the bottom dome to securely hold glassware and a bottle or two of some top-shelf whiskey. I will definitely watch a couple of his videos and hopefully I can find some techniques and practice them.
 
#7 ·
man you lost me a long time ago,but then the top shelf whiskey revived me-lol. as lazyman said we need more of whatever?oh hell it's late saturday night ,have some whiskey and who cares-lol.
 
#8 ·
I suggest a table saw and a nice crosscut sled or at least an incra miter gauge. I don't even want to know how you would plan on beveling long pieces on a chop saw lol. Would be way better to use a track saw or even on a budget a circular saw and jig/sled made from plywood and 2Ă—4s.
 
#13 ·
Then Steve Garrison's videos that I linked to above are going give you the best tutorial that I have seen. It is a little pricey but he also sells an ebook for specific details as well as other information at his Spirals by Steve website. I have a couple of his ebooks and he is good about answering questions through email if you have any. You can also see the router jig he uses to make them round after gluing them up.
 
#14 ·
Radial arm saw, as long as the parts will fit within its capacity. A RAS allows clamping the work in ways the table saw doesn't, imo, and makes experimentation with angles easier because for something like triangles it won't require much in the way of jigs I think.

That said, a geodesic dome form could be pretty difficult to get perfect, but you can fudge the bevels so the joints are tighter on the outside. Today those digital angle finders that stick to a saw plate with magnets can make setting exacting bevels a lot easier than it used to be.