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View Full Version : Bent AL casting on Miter saw?



Jeremy Chisholm
10-10-2006, 11:31 PM
Ok, I'm pretty frustrated with a tool and not sure what the heck to think for a solution.

About six months ago I purchased a Bosch 4212L 12" compound miter saw (non sliding). This purchase followed about three months of reserach and comparison shopping, and very careful thought. I've had nothing but praise for the saw since the purchase, and have in general been a very satisfied customer.

When I checked the saw for square to 'fine tune' it (one of the saw's big selling features is it's ease of adjustment) immediately after purchase, it was well within my range of specs in every dimension (again, a very satisfied customer here). I've used the saw since purchase to trim to length 3/4" solid oak hardwood flooring. I've carried it to and from the worksite (on a Rigid MSUV), and have cut the ends off several thousand bf of lumber- all without a complaint.

So while preparing to cut to length several pieces of nice cherry for a bed I'm building, I was SHOCKED to find that the main fence, checked against a registered straightedge, is bowed inward a full .23" over 18"!!! :eek: No wonder some of my floor ends looked a little out of square- I'd simply attributed the 'off' look to operator error on my part (moving too fast). But it's true- the fence actually is bowed into a concave arc!

Any ideas? Did I do this to the saw somehow? Does it move that much with temperature? I'm flummoxed.

The fence is a three-piece unit- the bottom fence is a solid cast AL piece, looks like a the pic below (viewed from above, at the front of the saw). Attached to each "wing" is a sliding extension wing, also of AL. It's the lower, CAST AL piece, that is "bent."


Should look like this:



Actually looks like this: (proportions exaggerated for sake of clarity)



Thanks for any ideas- and I am going to contact Bosch USA.

JC

Richard Wolf
10-11-2006, 7:54 AM
This happens with most CMS. Stress from the bolts or a hard hit from a piece of wood not frimly against the fence will cause the bend. Remove the fence and carefully hammer on the half ring to straighten it out. The Al casting will move back to it's shape. When you reinstall, recheck as you tighten the bolts.

Richard

Jeremy Chisholm
10-11-2006, 8:05 AM
Thanks Richard, I'll give that a try.