cutting acute angles safely

[billvan]

see link:

https://www.garymkatz.com/Publicatio...cuteAngles.pdf

[LarryG]

For 3" wide pieces, I'd probably use my CMS. For a 30deg cut, a 15deg wedge against the fence would bring the blade angle within the 45deg range of my saw.

Alternatively, and especially for wider workpieces that might not fit on the CMS, I was going to suggest something similar to what pecker shows. A number of the workpieces could be ganged together, side by side and with the ends staggered to minimize waste, with a straightedge laid across them to guide a circular saw. Make the rough cut with the CS; then adjust the straightedge position as required to make a cleanup pass with a router loaded with a straight bit. (Add a piece of scrap at both edges, to control blowout.)

[pecker]

Maybe cobble together a jig/guide for a handheld circular saw. This jig/guide could incorporate a shooting board (look it up) so you could true up all your cuts with a hand plane, if you needed a more accurate cut than your circular saw provides.

I have something like this one...

but you could easily make something out of scrap for one specific angle.


You can also make something more elaborate to provide more support for the stock. Sort of like this picture, but with your guides at the prober angle.

[poolhound]

For stock 6' long, I'd be thinking in terms of moving the tool rather than moving the workpiece, if possible. That points toward your choice "b) attach to the CMS fence to get the correct angle."

But how wide is the stock, and what is the capacity of your CMS? A 30deg cut on a 1x8 (7-1/4" actual) will be 1'-2 1/2" long. On my 12" non-slider, with roughly a 9 1/4" crosscut capacity, I'd be limited to stock about 4 1/2" wide at that angle.

EDIT to ask two more questions: what is the material, and how many pieces do you have to cut?

I am still working on the design but I would say that the widest would be no more than 3". The material is Walnut and how many is tough to say at this point (still design dependent). Not a huge number i.e 100s but somewhere between 6 and 20 something.

The basic concept design as you may have guessed is a triangular structure, hence lots of acute angles that must be repeated.

[LarryG]

For stock 6' long, I'd be thinking in terms of moving the tool rather than moving the workpiece, if possible. That points toward your choice "b) attach to the CMS fence to get the correct angle."

But how wide is the stock, and what is the capacity of your CMS? A 30deg cut on a 1x8 (7-1/4" actual) will be 1'-2 1/2" long. On my 12" non-slider, with roughly a 9 1/4" crosscut capacity, I'd be limited to stock about 4 1/2" wide at that angle.

EDIT to ask two more questions: what is the material, and how many pieces do you have to cut?

[pelligrini]

I've used an additional 45 degree angle between the piece and the SMT fence on my tablesaw. Much like back when hand drafting when combining a 45 and a 60 to get other desired angles. I don't have a CMS, so I never tried a solution there.

A speed square clamped to the miter fence and the piece clamped to it makes for a quick & dirty cut. I used to have a simple jig of ply & 1x material making a nice clampable (and much safer) 45 degree. It got taken apart for use in something.

[poolhound]

I am about to start a project where I will need to cut a bunch of small acute angles < 30 degrees. To make it trickier many of them need to be on stock 6' long.

My CMS cant be set for much less than 40 the SMT around 35 and the miter gauge on my BS at 30.

The options I have come up with all require angled support jigs that will let me either

a) use the rip fence on either the TS or BS
b) attach to the CMS fence to get the correct angle
c) use the BS miter gauge or SMT

What have any of you folks done to solve this problem and which do you think would be the easiest and safest way to go?