Precisely cutting round forms in half?

[Jim Underwood]

I've wondered many times how one might cut a hollow form precisely in half or at an angle in order to glue in veneers or wedges.... I have a couple of hollowed pieces with splits that I thought I might be able to fix this way.

A bandsaw might do it, but that seems like it would make a rough cut. Trying it on the table saw seems dicey at best. Hand cutting it? Out of my league...

Any ideas?

[David Reed]

Make a jig to hold it securely then cut on the band saw. You will want to remove some material anyway for the 'filler', so true it up on a wide sander or just heavy sand paper on a flat surface.

[robert baccus]

Might try cutting it on the lathe. cut in at the middle 1/4" or so and finish with a handsaw in the curf you started. have your favorite squeeze hold the end and your beer.----------old forester

[Bob Hamilton]

I assume if you are trying to repair splits that you want to cut the form lengthwise rather than across. I would follow David's suggestion about cutting on the bandsaw and dressing the edges, either with hand planes or sandpaper on a flat surface (or both). Figuring out how much filler to add to replace the material lost to the kerf and dressing will be the hard part unless you have fairly thick walls to allow turning it back to round after it is repaired. The thinner the walls the more accurate you will need to be. The width of the filler required to maintain the original diameter will change as the diameter of the piece changes so a piece that tapers will require a tapered filler if your walls are too thin to bear much stock removal.

Taping one side of the split and filling with a liquid filler like epoxy or similar would be easier but I can't say I have had much success trying it. My final pass always seems to open up an air bubble or something that requires re-filling and then re-turning which opens up another air bubble.....

Good Luck!
Bob

[curtis rosche]

leave a waste block on the ends, make a jig. screw the peice into the jig using waste block. then cut on tablesaw and then rotate to cut the otherside. or just use a bandsaw, then use a similar jig to send the half through a drum or belt sander to clean the cut.

or just get a laser cutting machine and hope it doesnt reflect off anything :rolleyes:

[Jim Underwood]

Bob - Yep... lengthwise splits that need patching up. Funny about the epoxy. I have the same problem...

David Reed - Band saw it is.. but how to make the jig?

Curtis - You gave me just the idea I needed- we use that method to cut legs in half on the tablesaw. However, I think these forms are too big in diameter to cut on the table saw, but I do have a friend with a brand new bandsaw that has enough capacity...

[curtis rosche]

how big is it that you cant cut through it in two passes flipping it over?

[Jim Underwood]

At least 8 inch diameter...