Mendel 90 backlash springs ?

Hi guys,

I have almost all of the parts for my printer except the springs ...

I have been watching Madmax' Mendel90 construction series on Youtube and he uses two springs for the z-axis (x- idler and x-motor end) to deal with the backlash, just wondering if anyone could tell me the size of the springs I should buy ?



thanks heaps

Jeremy

In the BOM I generated I have only the two springs for the extruder, I have also read about springs for mounting the heated bed, what sizes would they be ?

Coming from an oritinal Prusa Mendel with springs and going to a Mendel90 using stand-offs (hex pillars), I will not be going back to springs on the bed. Leveling the bed has been much easier and the bed stays very rigid even when moving at higher speeds.

Thanks remailed ! So I won't use the springs for the bed ..... Any idea of which springs I should use for the x-idler and x-motor ends ?

Thanks

Jeremy

The X-axis belt has a tensioner but the design has no springs. That is a madmaxx addition from his earlier experience with a traditional Mendel.

Nophead has some familiarity with the traditional Mendel design (I was told that he produced a Mendel kit before designing the Mendel90) and he must have decided the springs are not required.

Regards,
Neil Darlow

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I try to write with consideration for all nationalities. Please let me know if something is unclear.
Printing with Mendel90 from fedora 25 using Cura, FreeCAD, MeshLab, OpenSCAD, Skeinforge and Slic3r tools.

I may have miss worded the description of the springs,

They go on the threaded rod to separate the two nuts in the x idler mount and the x motor

The X ends no longer have provision for springs. I found they are not required on Mendel90.

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[www.hydraraptor.blogspot.com]

Fantastic -- thanks heaps Nophead !
I received my printed parts the other day, and I noticed a rectangular shape inside the X-motor mount/bracket ... I checked the stls (and its there two), I have to remove it to fit the motor, but I just wondering if its part of the support structure ? (If you could have a look at the picture that would be great)

thanks so much

Yes it was support structure but that is an old x-end. It was replaced with this [github.com] six months ago.

That version did have provision for a spring and a second nut.

Edited 1 time(s). Last edit at 03/21/2014 08:18AM by nophead.

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[www.hydraraptor.blogspot.com]

Thanks Nophead, yeah I came across the new end while only the other day - I downloaded the github file last year, but I could always print the new end once I get the printer running...

- because I am using the old x-ends do you think I should get some springs ? - would there be any reason to use the second nut without the spring ?

thanks so much

Jeremy

I have never fitted the second nut or the spring on a Mendel90. I needed them on my Prusa so I kept them in the design. I think they were only needed in the Prusa because it was very difficult to align the z axis properly. When the axis is aligned and free moving gravity prevents backlash.

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[www.hydraraptor.blogspot.com]

Cool stuff,

thankyou so much for all of the hard work you have put into the design - it is a pleasure to assemble

Jeremy