Anybody having problems with the fence on the Bosch 4100 table saw ?I've been using mine for about a year now without any real problems but yesterday noticed that the fence tilts out of perpendicular / square to the table when I tighten it down. I cleaned everything possible, checked for broken parts, adjusted the rear tension but when the fence is locked down it seems to torc itself about a 1/8" to the right of the blade. The only ( temporary ) solution I have is to spring clamp the left hand side of the fence down onto the track it runs in / on. Any ideas ? this is driving me crazy since it essentially renders the saw usless. Thanks.