Aligning the axles, Impossible screw placement

[NBull 14]

Hi im trying to check align on the axles using the alignment pins. (have been done before) but the right side x axles the one over the camera i cant get in a position where i can get to the screw. its almost like it have jumped a tooth on the wheel. but the the printer wassent that off alignment. so dont think it have skipped a tooth.

 

So big question is if i should skip a tooth to get to the screw. i can also make a new alignment pin where the groves have ben shifted half a spot, but then i'll probably get the same problem on the other side. so any suggestions?

Edited November 14, 2019 by NBull

[Smithy 1,146]

Just loosen the screw and realign the pulley roughly to reach the set screw. Then use the alignment pins for fine tuning.

[NBull 14]

So skipping a tooth on one side. 

 

I just find it weird that the two set screws can be so much offset compared to last alignment.

Edited November 14, 2019 by NBull
spelling

[Smithy 1,146]

I don't know what you mean with skipping a tooth, but you can basically loosen all pulleys and bring them in a position that you can easily reach the set screws, then start the aligning process.

 

When it was ok the last time you did the alignment, then probably one of the set screws was not tight enough.

[NBull 14]

I will try and explain it better, it can also be that im just doing it wrong!

 

I use the comb tool, but in every groove the screw is not possible to get to, if the rod was placed in-between two grooves it will work.

Thats why i wanna move the wheel one tooth over on the belt so that the screw is better placed when using the comb tool.

[johnse 31]

That axle is just an idler, so moving the gear one tooth on the belt shouldn’t be a problem. The curious thing is that you didn’t have this problem last time you set it. Is the matching gear on the other end of the rod also foo in the same manner?

[fbrc8-erin 298]

If you loosen 2 screws at opposite diagonals then you can rotate them totally freely. 

[gr5 2,234]

If the gear in the photo is a problem getting to the set-screw then tighten that one in any position and instead loosen the other gear on the same belt.  Hopefully that set screw will be positioned better.

 

You should only need to align 2 of the 4 pulleys as fbrc8-erin is hinting at.  It can be 2 diagonal ones, or two across from each other.

[NBull 14]

19 hours ago, gr5 said:

You should only need to align 2 of the 4 pulleys as fbrc8-erin is hinting at.  It can be 2 diagonal ones, or two across from each other.

I was thinking that i was just move the problem to the opposite side doing this. But it is correct i only need to align the wheel on one side. So its just me overthinking the problem. Blinded by the fact that I couldn't make both sides fit at the same time.

 

A side note, are there any need to check the small screw holding the wheel on the steeper? I cant see any way to do this whit out removing the steeper completely. Which i would prefer not doing.

 

[gr5 2,234]

For alignment purposes you don't need to alter this however some printers don't have that set screw tight enough.  The symptom is that the part shifts occasionally in X or Y.  But this is rare on UM2 and newer printers.

 

However also note that I am able to get at those pulleys with the green hex driver supplied with UM2 printers but I don't think supplied with newer printers.

 

Also note that you need to tighten the hell out of all these screws.  Enough that the steel shaft of the driver is twisting a bit.  Enough that if you used the short end of a crappy L shaped allen wrench your fingers will hurt after.  The set screws on the long belts are not as critical as they are doubled up and push with half the force as the one on the stepper motor.

 

[NBull 14]

Thanks for the answer, the question for the steeper screw was more ment as a "service tightening" so since I don't see any noticeable signs that its lose I'll just let i be.

 

But I think I have to get a L shaped wrench, don't really feel like i can tighten the screw well enough with the screwdriver. 

[Smithy 1,146]

Get one with a ball head, then it is much easier to reach the screw.

[NBull 14]

Aren't you more likely to damage the thread with a ball head.

[Smithy 1,146]

Never had any problems with it....