Well here goes... Aluminium frame router design

[CharlieRam]

So I stripped the carriage, 119 ball bearings, measured quite a few of them and they were 3,975-3,988 ish so my measurement last night was good, still notchy :-(

Would the lack of one ball really cause this issue? degreased and checked all ball tracks, checked the end plastic things by pushing the balls back and forth and they seem ok? Could the plastic cage thing be chafing?

Just out of interest I got some digital kitchen scales on the end of each rail and pushed on it until the rails started to move, the good one started to move at about 400g of pressure, the notchy one was just over 1000g, for info the rails are 375mm long.

BTW, the brand is PDF and model is DFH20A