Easy way to tension the Z belt
Easy way to tension the Z belt
While rebuilding my Z axis carriage, I decided to do a better job of tensioning the Z belt, since it was always much looser than the other belts on my machine. After a bunch of pulling, lifting, fastening, and unfastening, I had a really good idea.
Just loosen the Z motor bolts, and shove a wooden door shim in between the motors from both sides:
Then tighten the Z motor bolts, and remove the shims. I had to use a hammer to get them out, but you might be able to just wiggle them free.
These shims are cheap and easy to find, I think my hardware store sells a pack of a dozen for $2.
Just loosen the Z motor bolts, and shove a wooden door shim in between the motors from both sides:
Then tighten the Z motor bolts, and remove the shims. I had to use a hammer to get them out, but you might be able to just wiggle them free.
These shims are cheap and easy to find, I think my hardware store sells a pack of a dozen for $2.
Shapeoko 3 #192 - Complete! Needs limit switches.
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Re: Easy way to tension the Z belt
Yeah, I had to use a small pry bar on mine, and I worried about bending the motor shaft.
Added to the wiki.
Added to the wiki.
Shapeoko 3XL #0006 w/ Carbide Compact Router w/0.125″ and ¼″ Carbide 3D precision collets
Re: Easy way to tension the Z belt
This is how I tension mine too. Works a treet.
Re: Easy way to tension the Z belt
I use wedges to tighten my X axis as well, leave them in place, then tension the Z axis motor the same way.
Re: Easy way to tension the Z belt
Major kudos, CastIrony! This saved me tons of grief on Friday. In the middle of running a few projects, the Z axis just gave up and barely skimmed the surface. Thankfully, I still had a few shims in my tool closet (my wife - God bless her soul - used most of them as paint stirrers).
Ten minutes later, I was back to making a pile of oak chips. Cheers!
Ten minutes later, I was back to making a pile of oak chips. Cheers!
Shapeoko3 #1153
Re: Easy way to tension the Z belt
Some reason my belt was already tight with the stepper in the lowest position. I had to loosen the two 15mm spacers to gain enough slack to get the belt over the top pulley. Once everything was routed correctly, I tightened those two spacers which tensioned the belt without having to raise the stepper.
Re: Easy way to tension the Z belt
Do you have the old or new style Z carriage plate? The old one was a little bit more adjustable, which might explain that.KAScnc wrote:Some reason my belt was already tight with the stepper in the lowest position. I had to loosen the two 15mm spacers to gain enough slack to get the belt over the top pulley. Once everything was routed correctly, I tightened those two spacers which tensioned the belt without having to raise the stepper.
Shapeoko 3 #192 - Complete! Needs limit switches.
Re: Easy way to tension the Z belt
CastIrony wrote:Do you have the old or new style Z carriage plate? The old one was a little bit more adjustable, which might explain that.KAScnc wrote:Some reason my belt was already tight with the stepper in the lowest position. I had to loosen the two 15mm spacers to gain enough slack to get the belt over the top pulley. Once everything was routed correctly, I tightened those two spacers which tensioned the belt without having to raise the stepper.
Hmm, I'll assume it was the original style. It was the spark fun edition purchased Dec 2015. I just got the upgraded (front) Z-Plate few days ago.

What I don't have is that adjustment screw on the back plate that puts tension on the z-belt pictured here.

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Re: Easy way to tension the Z belt
Pick up a stainless steel SHCS at your local hardware store.
Shapeoko 3XL #0006 w/ Carbide Compact Router w/0.125″ and ¼″ Carbide 3D precision collets
Re: Easy way to tension the Z belt
WillAdams wrote:Pick up a stainless steel SHCS at your local hardware store.
That would be sort of obvious if the plate had an adjustable slot for the bottom guide pulley and a threaded bung welded to the plate for that steel SHCS tension screw.

Maybe this is a Sparkfun thing?
