help with angle cut on table saw

[Eric]

I'm making a 4 foot tall triangular structure. Each side of the triangle structure is a separate piece. All 3 pieces will eventually be joined at each point of the triangle. Each side of the triangle uses two 1.5" x .75" boards 4 feet long, one at each edge. I need to cut the long pieces so that when 2 sides of the triangle come together it will make a

60 degree angle. I'll end up with a triangular tower 4 feet tall and 10 inches wide on each side. I hope I'm explaining this clearly enough. Each 4 ft piece is a runner, one on each side of the peak (so 6 pieces total) How do i set up the table saw to cut the long edge pieces so that when they come together i get a total angle of 60 degrees? I looked at running the board through on edge with the blade tilted 30 degrees away from the fence but the base of the blade is very close to the fence if i do it that way and i dont think thats right so i havnt actually made that cut yet, seems wrong somehow. I'd appreciate any hints tips etc Thanks Eric

[bob]

Can't you just set the blade tilt to 30 degrees and run each piece through inside face down against the miter (miter set to 90 degrees)? When you put the two edges together, 30+30 = 60 degrees?

[Lew Hodgett]

This jobs begs for a 30 Degree jig and a router with a straight bit.

You clamp the part in the jig, the jig has a surface for the router, equipped with an edge guide, to slide on such that the bottom of the straight bit cuts the desired 30 degree surface.

Make one pass, turn the piece end for end, re-clamp, make final pass.

Take your time making the jig, all angular errors will result in a cumulative error.

IMHO, definitely NOT a table saw job.

Lew

[Limp Arbor]

If you don't have a tenoning jig for your saw you can make one like this:

you could just clamp the board to the jig and slide it along the fence.

You are right not to try it 'freehand'.

If you have a miter saw you could also make the cut with that by placing the board straight in. Again you would need to clamp the board to safely hold it.

[Limp Arbor]

If you don't have a tenoning jig for your saw you can make one like this:

you could just clamp the board to the jig and slide it along the fence.

You are right not to try it 'freehand'.

If you have a miter saw you could also make the cut with that by placing the board straight in. Again you would need to clamp the board to safely hold it.

[Leon]

Probably not, triangle angles are difficult to cut on a TS. Cutting at 30 degrees would result in a six sided frame. Using the blade tilt gauge or miter angle gauge you would need to be able to cut at 60 degrees to have a closed 3 sided frame.

To end up with a closed frame the "cut"angle degrees need to add up to 360 degrees. Typically you determine the needed angle setting by dividing the sides into 360 and then dividing by 2. Same with a triangle.

If your TS blade or miter gauge could be set to 60 degrees or greater you could cut the triangle angles needed. The only way to cut at 60 degrees on a TS is turn the piece 90 degrees from the normal position and then set the blade or miter angle to 30 degrees. Having the end of the board against the fence on the miter gauge is difficult to do on narrow pieces.

[David G. Nagel]

Attach a sacrificial board to the fence. This will enable you to move the fence right up to to the saw blade without damaging the blade or the fence. If you don't want to use tenons to attach the sides together you can use biscuits.

Dave N