Welcome! Log In Create A New Profile


Mounting the threaded rod

Posted by khiraly 
Mounting the threaded rod
December 17, 2008 01:46PM

I have finally built my repstrap mechanically (mcwire-variant), what is left is only the motor mount and the threaded rod.

I have modified the original design, I use 6mm diameter rod and
teflon (ptfe) block (drilled through 6.1 mm drill bit) as guide.

All the stages moves a bit hard, because the teflon block and the steel rod interlock(is this the right word?) firmly, need a bit of wearing.

On the mcwire design page:

It looks like, the threaded rod is only attached to the motor shaft.
I dont think it is enough in my case.

So the question is:
- How should I mount the other end of the threaded rod?

I will post photos tomorrow.
Re: Mounting the threaded rod
December 17, 2008 02:04PM
Not hooking the other end to anything eliminates the need for exact alignment. That's what I do with Tommelise 2.0 and it works just fine. smileys with beer


Hell, there are no rules here - we're trying to accomplish something.

Opportunity is missed by most people because it is dressed in overalls and looks like work.

Thomas A. Edison
Re: Mounting the threaded rod
December 17, 2008 03:31PM
First, make sure your stages move smoothly by hand. If they are harder to move at one point than the others, then your rod could have a bend or a defect in it.
If it is a bend, see if it is a physical bend or if the rod is bending due to loading. If it is a physical bend replace the rod, if it is bending due to loading, then check the alignment and/or end play. If there is a defect in the rod like a little bump, then use some fine grit sand paper or a whetstone to get the bump(s) out.

If it is moving smoothly, but just too tight then the first course of action is lubrication, lots of lubrication.
If it is still too tight after lubrication, I'd check and make sure the rod really is 6 mm. Depending on the quality of the rod it might be off by 0.1 mm.
If it is bigger than 6mm, then use sand paper wrapped around it to polish the shaft down.
Then there is the hole in the teflon, if you used a standard drill, the hole is
probably not perfectly round. Run sandpaper around the inside of the hole a bit to smooth it out.

For the end mount, you could use another teflon block (or wood, or delrin, or whatever). The quick way to do it is to put a through hole in the mount block, and use a shaft that sticks out about 5 mm past the end of the hole. On the end of the shaft sticking out put a flat washer on and then put an e-clip on the shaft after that (or maybe that should say use an e-clip with a flat washer between the clip and the block). You could also use locking nuts, a pin, or a big glob of glue.
Re: Mounting the threaded rod
January 08, 2009 11:54AM
> I will post photos tomorrow.

Sorry for being late.
I made some videos the day before yesterday. You can see it here:

From since, Im olways running the Z axe for wearing a bit...
Sorry, only registered users may post in this forum.

Click here to login