Miters with a cold saw HELP

[barn full]

I have been having lots of trouble cutting miters in steel 1 1/4 angle iron. I am using the Milwaukee 14" dry cut saw:

Basically, the on board clamp holds the work piece perfectly for 90 degree cuts, but for any type of miter, it doesn't hold the work solid. The blade ripped the work piece out of the clamp and launched it dangerously. The blade is trashed now.

Am I missing some bit of critical set up to make these cuts? The saw makes perfectly machined pieces when it works correctly so I want to use it for this purpose but i can't afford to replace the blade or go to the hospital.

 

[tube_guy]

How are you clamping the angle iron into the saw's vise? For 90 degree cuts, it should be clamped with the point facing up, like this '^.' For miters, most of the time, that's not possible due to the direction of the angle required on the finished piece. If you have to clamp the piece with a flat side against the base of the saw, like this 'L', you should make something to place into the angle iron so the vise will clamp the angle iron more securely. Sometimes I stick a piece of box section steel into the angle iron so the vise will squeeze the box section steel against the vertical portion of the angle iron and the back of the vise. But 45 degree cuts can still be a challenge because the component of the clamping force parallel to the back of the vise is starting to get large and the clamped pieces tend to want to slide around.

 

[Zrexxer]

For any miters on steel I put a pair of Vise-Grips on the material at the back edge of the vise... it acts as a stop to keep the blade from pulling the material through the vise when it's at 45°.

 

[barn full]

Zrexxer: are you clamping the piece to the fence with the vise grips or just using them as a stop. That's a great idea.

Tube guy: Yeah, the finished pice will not work if I place it in the vise with the pointed side up. So it goes in like an L. I haven't worked with it since the I posted but I think I figured out one problem and a solution. When the vise is turned for making a 45 degree cut it places the work piece at the back of the saw blade where the teeth pull thie peice up and back. Pulling in that direction overcomes the friction from the vise and rips it loose. My plan is to add a wide Aux fence to the vise that will place the work piece at the front of the blade where the teeth will push the piece against the fence, rather than pull away.

 

[alex71]

To the OP--you're using a dry cut chop saw. A big difference between these and most cold saws, is that the cutting head on the cold saw will swivel in both directions to allow + and - mitering, similar to a miter saw for wood. Your saw only has a swivel vise, and as you've found out you can miter the work in one direction relatively easily, but the other direction is a pain.

 

[barn full]

To the OP--you're using a dry cut chop saw. A big difference between these and most cold saws, is that the cutting head on the cold saw will swivel in both directions to allow + and - mitering, similar to a miter saw for wood. Your saw only has a swivel vise, and as you've found out you can miter the work in one direction relatively easily, but the other direction is a pain.

Yep. Maybe its time to fab a swivel mount for it.

 

[sberry]

I rarely cut miters on a chop saw, I usually make 90 and nip the corner with a plasma. I actually seldom use a 45, I design with cuts in mind.

 

[barn full]

I rarely cut miters on a chop saw, I usually make 90 and nip the corner with a plasma. I actually seldom use a 45, I design with cuts in mind.

Was your set up in FarmShow magazine? Looks familiar.

 

[sberry]

Yes, it probably was. I had a few things there over the years.

 

[barn full]

Yes, it probably was. I had a few things there over the years.

Very cool. I have a few things I need to submit. We raise dairy goats and I have done a lot of "invented in farm shops" mods. I love that magazine.