Miter Saw Fix

One of my earliest “nice” tools was a compound miter saw. I bought a “new”1 Ridgid 10″ miter saw about 15 years ago. It’s been pretty handy over the years, but I noticed last year (on my finishing storage rack project) that the fence was bowed. As the blade would cut through he piece, the piece would then pinch into the blade. At best, that just ends up messing up an otherwise clean cut. But worse, it can be a bit dangerous any time a piece is pinched like that (at least with a miter saw, the blade is generally pulling it downward into the support). I searched for a replacement part, but those are no longer available for this model.

Thus it was time to just try to fix it. The fence is a very oddly shaped piece of aluminum. I had to unthread the four hex bolts holding it in place. They were pretty tight, to say the least.

I nearly broke my Allen key set getting these bolts loose

It’s important to have a references for “straight” and for “square” and so any maker should know what the flattest and most square things in their shop are for a true reference. I don’t have any machinist’s squares or a heavy, cast-iron table saw, so I just make do with some aluminum tools that are pretty good. I grabbed the large dry-wall square to use a flat reference. Sure enough, there was about an 1/16″ bow in the fence.

Tough to capture with a cell phone camera, but both points in the middle are off the straight edge

I placed some scrap pieces on the garage floor and used a 4lb sledge to hammer the center of the fence. Aluminum is a brittle metal, so I had to go slow. This usually mean 1-2 firm whacks and then check to see if it was level. I actually went a bit too far, and the fence started rocking side-to-side on my straight edge. A couple of whacks on the other side got it right on. I did have to shore up one side as the points nearest the blade weren’t in line any more (or maybe they never were?).

Precision sledge work

This was the most tedious part, but I got it so I could just slide a piece of paper under it. That’s going to be about as accurate as I can get using this method I think.

A lot of effort to close a very small gap

The fence is attached with round (or fixed) holes on one side and slotted (or adjustment) holes on the other. I got the fence placed on one side and then used my aluminum speed square on the other. This is where a good machinist’s square would be used if I owned one, but again – this whole fix is a bit rough anyway, so the speed square is good enough.

Not the ideal square device

I also noticed that in addition to the “fixed” fence having been warped, which would have just resulted in the same issues. So I quickly adjusted that one too (no sledge hammer required).

While tightening the main fence, I noticed the bolt-on wing wasn’t in line

A quick test cut and I immediately could tell the piece didn’t move a bit as soon as the blade cut through. And, just as important, it was square! (well as sure of square as I can be with my tools!)

  1. Though as it turns out, it had been used to cut some stuff and returned (probably by some 2nd rate contractor), only to be sold as “new” by Home Depot. But it worked fine and I needed it for something at the time, so I just lived with it. []