I feel that I need to share this one with you.

gplus
(Markus Granberg) #1

I feel that I need to share this one with you. I have had a lot of problem moving from linear bearings to bushing mainly because of how sensitive bushings are to over constraint. I found it impossible to print two holders that was lined good enough to make the bushings slide as smooth as they do “alone”. One way I found out that works a little is to heat the mounting and let the bussing settle. This however still does not give you that super smooth motion as a “alone” bushing on a rod. And it might mess up lining to other things as well.

I found out that the solution is to remove “constraints” from the bushing mount and only lock the direction that is required, then the rod is the only thing thats lining up the bushings = NO BINDING! And the motion is super smooth! This basic test plate is a easy proof of this (download it and give it a try!)

And if you are running linear bearings give bushings a try. They are silent, cheap and runs fine on drill rod.

stl (12mm rod = 18mm dy bushing)
https://drive.google.com/file/d/0B7kgdYk7GVumT01qQnIxX092QVk/edit?usp=sharing

solidworks 2012

https://drive.google.com/file/d/0B7kgdYk7GVumS1hvRVFGbk43aDg/edit?usp=sharing

(Nigel Dickinson) #2

Are you running non heat treated rods. As that would be my only reason to swap to solid bearing.

(Dale Dunn) #3

No worries. “Languish” is a fair description of me trying to speak German.

Nice work making a simple sleeve into a self-aligning bushing.

@Shauki needs to see this.

(Markus Granberg) #4

Nigel your post got removed for spam (dont know why?). Yes the bushings that I use (and bushings in general) does not need treated rods. But they still need to be at least H8 in dimension tolerance. The image is misleading I dont use that type of bushing, I use ptfe coated (but the ones in the picture works fine to but is heavier).
http://www.mecmove.se/glidlager/bkbBK1.asp

(Nigel Dickinson) #5

@Shauki thanks, the fit isn’t a problem for me as I can make the bushings to fit the rod as I have a lathe.

(Markus Granberg) #6

i was wrong H7 is fine too.
Shauki I cant say that i understand were your problem is (im not familiar to quadstrap). The bushings that I use (12mm axle) are about 0.5 Euro here in sweden :slight_smile: