I agree John, they fit the saddle but not the bed!Funny you mention rubber, I was going to use some wet suit material, I assume neoprene, that my brother has a lot of offcuts from a previous job, but didn't like the idea of the seal picking up a chip and then dragging it backwards and forwards across the bed. Having said that, I am sure felt would do just the same unless if fits tight to the bed rails. Given that my Student is a roundhead from the early sixties, it has remarkably little wear on the bed, and I wanted to keep it that way, so I took the saddle off, replaced all of the ball lubricators, which had long since lost their balls, punched the plugs of compressed swarf out of the oil holes, and generally gave the saddle and apron a good sorting. The difference to the feel of the saddle was amazing. Not difficult to do, but involved, leadscrew and feed shaft off, which meant I had to go in the feed.QC gearbox, noticed the spacer and circlip missing from the leadscrew, and also that someone had been in before me! Found the spacer and the circlip loose in the gearbox bottom, plus another circlip partially jamming the selector gate, ended up taking the front off the qc gearbox to clean it all out, and it is now silky smooth. Went on to change the oil in the head stock, and clean the sight glass, so naturally, having been successful with magnet treasure hunting in the QC/feed box, I dip my magnet into the head stock, and find the original drain plug, still resplendent in Colchester green,(someone has been in here too, tightening the end-float on the spindle bearings) and another circlip and spacer, which I think is from the feed reverse mechanism. When I move the machines to the other end of the shop, and have a bit more room around the machines i am going in again to replace the rather noisy spindle bearings with another set of Gamets that appear almost brand new. I will investigate the reverse mechanism at the same time, but it appears to work fine, so I wonder if the originals had been "lost" in the oil, and replacements fitted. I try to make all my seals "Hermetic", and being a Yorkshireman, you could also call me Herma-Tight.