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shoeswith
15-06-2015, 02:19 PM
Hi

I have a quantity of 25mm with a 1.6mm wall thickness polished stainless steel tube I was wondering if it would be possible to run round (LMU type) linear bearings on it. The stainless steel tube definitely seems harder than mild steel tube but it may not be as hard as proper ground linear rail. Its for a wood router so its probably not getting that much abuse and the difference in accuracy is not going to be a factor. I am wondering if the small contact area of linear bearing will wear the tube or even if the tube will deform under the pressure of the bearings. Has anyone tried this?

Thanks

Robin Hewitt
15-06-2015, 05:49 PM
I thought stainless tube was usually sanded or sanded and polished, not ground.

OTOH just because I think something doesn't make it true :thumsup:

shoeswith
15-06-2015, 06:33 PM
I thought stainless tube was usually sanded or sanded and polished, not ground.

OTOH just because I think something doesn't make it true :thumsup:

Yes you are probably right its probably sanded and polished. I've measured it with a micrometer and it seems pretty accurate. I can't see why in this case it couldn't be substituted for round linear shaft. I have it from a previous project so its going to cost me nothing. Is 1.6mm too thin a wall thickness? It's harder than mild steel ive drilled it but I've never drilled standard linear shaft. People say its hardened but actually how hard is it?

totts
15-06-2015, 06:42 PM
Linear shaft is induction hardened, which means the outside layer is hard. Around the 50-60 hrc. The middle of the shaft is usualy soft enough to drill and tap.

The stainless steel tube will pit after a short while where the internal race of balls will wear into the stainless shaft loosing the accuracy and smoothness.

Also tubing will be far less rigid thand solid hardened shaft/ supported shaft.

If you want to use the stainless shaft then you are best off using ferrite/ brass bushes lightly oiled.

Hope this helps

Desertboy
31-07-2017, 04:19 PM
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