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pp-gp0363 too tight tolerance to insert metal (AS-PR... belt assy)
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The PP-GP 0363 part is too tight in the X by aprox 1mm. If we would open that part up just a bit, then when the completed part, AS-PR0122 has the belt assy installed, it will fit. As it currently is it requires the belt assy to be jammed in.
Recommend a change to the PP-GP0363 part.
Part number can stay the same.
Roll in change.

Event Timeline

This would be a change order to update this.

@west @kent @Steven


tutley added a subscriber: tutley.May 20 2019, 7:37 AM

@david.hall can you clarify the issue? is this an issue with inserting brass inserts?

oliver added a subscriber: oliver.May 20 2019, 7:47 AM

@tutley I believe this is talking about the YZ idler that the belt attaches to.

@oliver @david.hall we need the yz idler pocket to be relatively tight so it doesnt turn when tightening to increase belt tension and cause the belt to sit crooked. If it is turned this will cause the belt to ride up one side of the idler bearings and end up rubbing

@tutley The tightness is in the X position on this part. It does appear to fit in the Y position, but the X is so tight, that you have to use pliers to get the The AS-PR0124 metal piece in the printed part.

@david.hall then something must be up with the slice or the machines these are being printed on. this pocket is modeled to the same dimensions in x and y. If it is fitting one way and not the other, then the parts arent printing dimensionally accurate

I agree that this is a slice or model issue, which is why I put the ticket in. The rest of the parts that are printed on the same printers have no tolerance issues, so it would seem that we either have too tight of a tolerance and thermal swell has not been accounted for, or we have another issue with the part. I am unsure of the ultimate cause for this, but we will need to look into it so that production can build the assembly without issue. Thanks

@david.hall if the part is coming out dimensionally accurate in one axis but not the other then we have to evaluate which axis is failing based off of the orientation of the print. From your earlier comments, I am gathering that it is fitting fine from the top of the part to the bottom (Y axis) but not fitting in the left to right (X axis). Using some calipers, can we verify the distance across 10 prints worth of parts (30 individual pieces)? Worst case scenario we can use these data points to determine if machines in cluster are out of calibration.

@west @tutley I think slice might be the easiest solution for this, but I think a model change might help with hitting the tolerance a little easier. The right angles in the X axis of the part which frame the belt path will cause issues when printing at higher speeds. If it was sloped down to each height this will discourage travel blobs from forming on sharp corners.

tutley added a comment.EditedMay 20 2019, 2:14 PM

@david.hall it is not a model issue, it is a printer or slice issue.
Only as a last resort should we touch the model. These were all fine throughout prototypes, alphas and betas. So something on cluster's end changed

we are going to try to re-slice it first, but again may to adjust the model.

@EricNugent are you able to reslice this and test it please?

@EricNugent have you been able to test this at all?

@DaniAO I was able to get some initial test theories underway. The best solution has been to lower the layer height, which will increase the print time. Lately I have not been able to give slicing full attention though since we have been assisting in calibrating production machines