# 4900 Carriage Freeplay



## robotwizard (Aug 10, 2016)

Can't find any specs on what the vertical freeplay on the carriage should be for the 4900. I measure approx .020 with magnetic base and dial indicator. I removed shims on rear but not enough. I did the trick of tightening carriage lock until slight drag to check for bed wear, but don't have any tight spots along bed. Should I find a surface grinder and take the bed clamps down a bit or should I look for another good carriage? and also a good bed? thanks


----------



## wa5cab (Aug 10, 2016)

I don't have access to any specs, either.  But would assume that vertical clearance should be no more than 0.003" to 0.005".  If it doesn't get tighter toward the tailstock, the bed is probably level.  As there is no way to know whether or not a replacement carriage would fix the problem (and you'd be stuck with two of them), I think that I would have the carriage ground.


----------



## 4GSR (Sep 3, 2016)

I've taken the hold down strip and milled a step on them as needed to get the .003-.005" running clearance needed.  It don't have to be exact.  It's mainly there to keep the saddle from rearing up when cutting on larger OD stuff.


----------

