Z axis Belt - Tension (am I doing this right?)

[tank6035]

My belt is very loose too. I contacting support.

Edit 5/28/2015: Edward emailed me

"Regarding the belt - We apparently had a bunch of out-of-spec belts get delivered, and then subsequently shipped out to customers, such as yourself.
We have ordered a new batch of belts that should be delivered today or tomorrow. Once we take delivery, we can quickly ship you out a replacement."

[FabricatorCraig]

Not trying to be negative, but this DOES seem to be an issue for a lot of folks and I'm concerned that I will end up in the sam boat. With everyone being told to contact Carbide support, what has their response been? I'm curious as to the root cause... Design flaw? BOM issue with either incorrectly spec'ed or incorrectly picked parts? Missing, confusing, or otherwise flawed assembly instructions?

When you see enough repeated instances of the same problem, it would be nice to hear an official statement regarding the problem and either what the official/standard/accepted fix is or (and?) what changes might be made going forward to eliminate the issue.

EDIT: apparently I missed the edited/updated post right before mine. Out-of-spec belts...so a BOM issue apparently.

-craig

[WillAdams]

Out-of-spec belts...so a BOM issue apparently.

A supplier supplying an out-of-spec (in this case too long) product is not a problem w/ the B.O.M.

http://www.shapeoko.com/wiki/index.php/ ... 8B.O.M..29

Curently this is listed as:

23 1 S3074 GT2 Profile - 524mm Endless Belting

If something different is to be used, well, I'd like to know so that we can update the B.O.M.

[FabricatorCraig]

Out-of-spec belts...so a BOM issue apparently.

A supplier supplying an out-of-spec (in this case too long) product is not a problem w/ the B.O.M.

Sorry, Will. It was a generic, overarching reference to my BOM comment that mentioned several possibilities under that umbrella. Rather than being incorrectly spec'ed, the actual picked item was faulty (though not really the SO3 Packers fault because a last-moment visual quality control inspection wouldn't likely catch a slightly-longer-than-spec belt). My guess is the supplier of the belts will be much more closely scrutinized if they are used in the future...at least that's what I would do.

-craig

[StevenLee]

I have same issue with Z axis belt. My solution is 3D printing another GT2 pully.
I tried many different tooth 25-35, the GT2-30 pully is the best fit for my machine.
Now my Shapeoko3 is up and running

The 3d printed GT2-30 pulley vs GT2-20

The installed pulley


The attached file is the STL file and the openscad code,http://www.thingiverse.com/thing:858229 ( download and modify from thingivers http://www.thingiverse.com/thing:343343)
Hope this will help someone to get his machine up and running.
Good Luck

[edwardrford]

Clever Fix! Have you tested for interference against the z-rail, from the larger OD of your modified pulley, or did you modify the 30 tooth, to maintain the same OD (body) as the original 20 tooth?

For anyone who is having an issue with your z-belt - please email support@carbide3d.com - we'll put you on the list of people to send out a new z-belt to as soon as we get them.

This is a pretty odd case. More than 90% of all machines we've shipped *don't* have this problem, and randomly checking a few of the belts we have left, all of them are within tolerance and appear to be acceptable parts. The problem belts seem to be completely random.

Anyway, the new belts are due in any day (they've been stuck at a DHL facility about an hour from me for the last couple of days). Once they're in, we'll get everyone's belt shipped out the same day.

-Edward

[zymurgy]

I have same issue with Z axis belt. My solution is 3D printing another GT2 pully.
I tried many different tooth 25-35, the GT2-30 pully is the best fit for my machine.
Now my Shapeoko3 is up and running

The 3d printed GT2-30 pulley vs GT2-20

The installed pulley


The attached file is the STL file and the openscad code,http://www.thingiverse.com/thing:858229 ( download and modify from thingivers http://www.thingiverse.com/thing:343343)
Hope this will help someone to get his machine up and running.
Good Luck

Thanks for creating this. I'm going to give it a try while I'm waiting for my replacement belt to arrive. Though your STL file has some non-manifold geometry. I ran it through NETFABB (https://netfabb.azurewebsites.net) and I'm printing it tonight.

[WillAdams]

Another option may be wrapping the spacers w/ zip ties, which is what I’m trying now.

[kristenanne77]

Well now its my turn to order a belt.
Spent two days taking things apart and tweaking to get everything "lined up" and tightened as much as I could ..... but my belt is a teensy bit too long.
Foiled again! (And I didn't even get to the electronics yet). I wish my son's super cute Pomeranian was here to help me, but he moved and I'm on my own!
Contacted carbide. I hope I can get it done by Sept for the Orlando Makers Faire!
In the meantime, its a few more days of not using the table to for eating.

K

[eefits]

Clever Fix! Have you tested for interference against the z-rail, from the larger OD of your modified pulley, or did you modify the 30 tooth, to maintain the same OD (body) as the original 20 tooth?

For anyone who is having an issue with your z-belt - please email support@carbide3d.com - we'll put you on the list of people to send out a new z-belt to as soon as we get them.

This is a pretty odd case. More than 90% of all machines we've shipped *don't* have this problem, and randomly checking a few of the belts we have left, all of them are within tolerance and appear to be acceptable parts. The problem belts seem to be completely random.

Anyway, the new belts are due in any day (they've been stuck at a DHL facility about an hour from me for the last couple of days). Once they're in, we'll get everyone's belt shipped out the same day.

-Edward

@ Edward

If the GT2 pulley mount on a horizontal slot instead of a hole. Will that also make it easier to adjust the z belt tension or/and correct slightly larger belt.