z axis spring solution

Hey everyone,

I am finishing up my mendelMax 1.5 and I am noticing that when I try to zero out my z axis, at the very bottom when I turn the motor, the rod is turning slightly, however, the extruder seems to not move for a few micro turns, then all the sudden kind of clunk down to the bottom and make up the lost turns.

I am not sure what this is, but I have seen some use a spring solution in the Z axis between two nuts.

Anyone have any suggestions?

If I should try the spring solution, can anyone explain or point me to a link on how to do it?

Thanks!

What kind of Z-axis couplings do you have?

A pic would be good if you can.

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- akhlut

Just remember - Iterate, Iterate, Iterate!

[myhomelessmind.blogspot.com]

Look around on youtube. I watched a video a couple weeks back where someone demonstrated installing a spring in an x-end for the z-rod. It was exactly what you're looking for.

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ΜΟΛΩΝ ΛΑΒΕ

Do you mean one side of the X axis is hanging up when the axis is being lowered? If so, then your bearings on that side are binding on the smooth rod.

Everyone, thanks for the replies.

I discovered that my x carriage was not 100% level on both sides, so it was binding on one side.

Once I got it exactly level, this stopped happening.


Thanks for your help everyone!

The spring between the two nuts is a method used for anti-backlash. I've been using that method since my first RepRap. It works by putting opposite force tension on the nuts which in turn takes out any slack on the threaded rods. I recommend it. Its always served me well at least. It was a method that is borrowed from CnC builds. I used to build CnC's. I'm glad you got it figured out.

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Knimrod Wrote:
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> Look around on youtube. I watched a video a
> couple weeks back where someone demonstrated
> installing a spring in an x-end for the z-rod. It
> was exactly what you're looking for.

I found the video again for those that want to understand how it works: [www.youtube.com]

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ΜΟΛΩΝ ΛΑΒΕ

Reprap squad and knimrod, thanks guys. This may be an upgrade I try to make once I get printing if I am not happy with the accuracy.

Very helpful, thanks!

Ya no prob we are always here to help. I've never really compared the difference between with and without the spring for anti backlash. I have with CNC'S but never on repraps so if you ever do a before and after I would love to see the results. Keep me updated.

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--------------| For Everything |--------------------------
Check it out here:
[reprapsquad.wordpress.com].
---------| For Everything Prototype Related |------
Now featuring comp case mods:
[RepRapLab.wordpress.com]

--------------| Find us at Twitter|------------------------
@REPRAPSQUAD (RS Main)
[mobile.twitter.com]
@REPRAPSQUADHQ (ProtoLab)
[mobile.twitter.com]