View Full Version : "Drylin" linear bearings?

08-08-2007, 04:57 PM
I saw these here...
and they look like they would be nice for some CNC type operations. It seems to be linear bearings of various types, made of some kind of plastic- "Drylin"

Looking at some of the various products, I am surprised to see that they are much cheaper than the typical ball bearing slides I'm used to seeing on Ebay. They seem to be rated for loads that would be OK for a CNC gantry or similar (just after my round tuit on the "to do" list:D)

Anyways I looked at the price of the liner alone, it's like $3 for a 1" one! It looks like that's the only part that I couldn't make myself, pillow blocks/bearing holders/whathaveyou seem like they're a hole in a piece of metal, not sure how much more complicated it could get. A quick glance at McMaster shows the hard-anodized aluminum shafts to be cheaper than the steel ones used by traditional bearings.

Anyways just wondering if any of you had any personal experience with these things, or similar products. They look like they would work well for someone on a college-student-level budget!

(no association, blah blah blah)

08-13-2007, 12:25 AM
Thanks for posting this website. I have several grinders that run linear bearings. They all use the recirculating ball bearing type. I am in the process of building another grinder for sharpening planer knives and I think these may be just what I need.

John Stevenson
08-13-2007, 04:43 AM
On the older type laser cutting machines we used to look after they had these recirculating ball bearing slides on the Y axis which was aboce the cutting area on the gantry.
Because of the fumes dust etc which would settle on the rails these had to be removed about every 6 months and washed out and the rails polished.

Every so often the ball slides would have to be replaced due to sticking.
One day our local supplier had no ball bearing slides and only had the dry lining ones so we fitted these as a stop gap measure whilst he ordered some ball slides up.

We found these to be far better as they didn't stick and get crud inside like the ball type.
This them meant you could clean and polish the ralis at longer periods without having to strip down.

We also did some routers with these and had the same results. Where they kept sticking with MDF dust the dry lining type kept on working.


08-13-2007, 02:37 PM

In the above link is a competetors product that I am familier with. I used to work in the automated production production and used the Frelon bearings sold by pacific. What I discovered that they were less prone to failure like the ball bearing type that would lock up and slide ruining both the shaft and bearing. The plastic type would wear and tolerences would open up causing other problems with alignment of the tooling. Frelon run dry would generate particles that had to be delt with, and when running lubed then they would have to be kept lubed or gum up. Like John said in a dirty environment they will handle "stuff" better that a rolling element bearing. Dry they have a higher friction that rolling element. They have an advantage that they will do linier and rotary motions where as rolling element usually inly do linier.

So the plain type bearings have there place, Understand what the limitations and advantages of each style are select the style that best supports your particluar need.

no neat sig line

08-13-2007, 09:47 PM
Go to the 'metalillness' website and search under 'linear bearings' by a charachter named 'rustybolt'. it might give you some ideas.