Fixing Pulley Innacuracy

[aklion 0]

If I'm still not too late. Can I get these bullets to GT2 belt width 9mm shaft hole of 5 mm. I need three bullets.

 

[hreedijk 4]

Recieved the pulley's last week, installed them yesterday, working like a charm.

Thanx again Markus!

[sigmaprojects 0]

Are these still available to order?

 

[foehnsturm 969]

Well, I'm somewhat irritated by Ultimaking's pricing policy. Currently, they sell 10 pulleys for 49.95 + tax. I don't know if the quality is still as low / varying as it used to be. But as far as I know they should be buying close to 1$ or 1€ / pulley.

Following the same policy I would have to ask for 150 € a set. I won't do that, but I don't want to sell immaculate precision mechanics quality for almost the same price tag as Chinese bulk ware, either. I feel some responsibility for my supplier and the value of his work.

 

[ji11 3]

I have been contacting you via pm. Got no reply...are the any pulleys left? Or will. There be an other batch any time soon?

[ballanux 0]

Well, I'm somewhat irritated by Ultimaking's pricing policy.

 

I'm an electronic engineer and I can tell you that the price of the electronics is easily more than 5 times the price of the materials, even if you are doing very short production series of boards that price is ridiculous!

Also the quality is bad, or at least they don't test the boards, the first ulticontroler I received had a bad SD socket, they sent me a replacement... and it had a broken transistor... I repaired the second board using the transistor from the first, but having to do that, again, is ridiculous...

 

[foehnsturm 969]

@ji11

I still have 2 pre-ordered sets left. If nothing happens until Friday one is yours.

 

[ji11 3]

Cool sounds great! Hopefully i will get them

[ulbie 0]

@foehnsturm

I would take the other set if it is still possible. I live in germany so delivery should not be a problem

If you need a pm please give me a sign

Thanks, ulbie

[baasb 6]

Ai, are you planning on making some more sets foehnsturm? I'd also like a full set... :mrgreen:

 

[irongland 1]

I too would buy a full set if you were going to do another run of them.

 

[baasb 6]

I'm sorry for those who hadn't had a chance to buy a set, I don't want to poke you an eye out but...

Man, what a difference! I was very sceptic at first but with all those enthusiastic replies.. I had to get a set for myself. Because the whole XY part had to be disassembled, I took this opportunity to also upgrade the slider blocks. I printed the reptar blocks (newest version). Also printed some external tensioners for the X and Y motors and used clothespin-springs to tension the long belts. Will post some pictures later. It runs so smooth now, very little resistance when manually moving the head. And because of the more accurate positioning and smooth movements, even with high travel speeds, it will travel back to the exact same spot every time, which greatly increases the XY surface quality! Somehow it's also much quieter (almost as quiet as an UM2).

One (important) thing I noticed when I was sliding the brass bushings over the XY rods was that, if you use machine oil as lubricant, it was much less smooth then with a silicon lubricant. The machine oil felt like it was behaving as a newtonian liquid! The faster I moved the bushing, the harder it became! So especially with the high speeds of 3D-printing, I'm going to use a silicon spray lubricant.

 

[jumpmobile 0]

Yeah, if there is a second/third (?) batch then count me in, too...

Will follow this topic.

I think i'm switching to GT2-Belts and Pulleys.

 

[baasb 6]

Here some photo's of the things that really helped me improving XY and Z accuracy.

The new pullies from foehnsturm make a huge difference like I said in two post above. After one print, however, I noticed that the Z-wobble was way more visible because it stands out in comparison with the very accurate XY. The Reptar XY Blocks are nice. They don't give you any accuracy improvements but removing the 6mm rods and printhead is super easy with these blocks. They don't have a belt-tension option so I used some clothespin springs for that. The smaller printhead is lighter so theoretically you can print faster but I don't expect much quality improvements other than I think this head just looks nice.

 

 

Fortunately, today, three flexible couplers came in which I had ordered earlier. Just by replacing the UM coupler with the flexible one, the wobble completely disappeared immediately! So for only a few bucks and no tinkering, one of the best upgrades :grin:

 

 

Two other upgrades/tools are these XY belt-tensioners and endcaps. I think everybody knows these endcaps by now, and be sure to print the ones where you can put some set-screws in them. The belt-tensioners are just perfect and really easy to set to the right tension.

 

 

Good luck with improving your machine!

 

[Nicolinux 288]

Hey BaasB, thanks for the infos. Where did you get the flexible couplers from?

 

[baasb 6]

On Ebay from a guy from China. It only costed 11,80 euros for three couplers including shipment. If you search for 5 to 8 mm flexible coupler, you can find many more suppliers on Ebay.

 

[LePaul 321]

BaasB tell me about the print head/feed system mod you have there.

My Ultimaker keeps blowing off the bowden tube and while there are a few ideas I have yet to try (since I can't print them!), I was curious about what you have done.

 

[jhertzberg 19]

How rigid are the flexible couplers along the axis? Do they expand, compress or bounce when torque is suddenly applied? It looks like a great idea, but I don't want to trade off z-height accuracy.

 

[baasb 6]

# LePaul

The printhead is here: http://www.thingiverse.com/thing:154845

It uses the same white insert as the original head to prevent the bowden from popping out. And the blue horseshoe holds this white insert in place. I never had problems with the bowden comming out. If I pull hard on the bowden tube it's very hard to pull it out and I have to push down on the white insert. I think you should check this white thing if it is tight enough arround the tube.

# jhertzberg

I did not test this other than printing a simple iphone casing. And I didn't see any changes in the layers on that print. It needs a bigger, or at least, higher print to evaluate that. But even if it's flexing/compressing, this effect should be the same at each layerchange and I think only visible at the Z-seam. A couple of UM users on this forum use the same couplers for direct drive on the XY-motors and as far as I know they have not reported any problems. I'll let you know when I've printed some more

 

[david-lawson 0]

@ji11

I still have 2 pre-ordered sets left. If nothing happens until Friday one is yours.

 

@foehnsturm any chance of getting hold of a full set of pulleys?

 

[drayson 75]

Guys, yesterday I found the time and upgraded my UM with the pulleys supplied by foehnsturm.

I have to say GREAT!!!

@ Foehnsturm: Thank you for providing it - they work like a charm...

The belts are running perfectly without "wobbling" and the noise of the whole movement is gone.

Definitely every Euro worth... :-)

 

[foehnsturm 969]

Thank you drayson.

To all who asked (and didn't get a response so far):

There will be another batch early next year. I have to order some 100 to get a reasonable price. I don't want to ask for a markup like Ultimaking but I have to control my financial risk. Therefore, I will start to ask for binding pre-orders in January.

 

[kitwashere 1]

I will be jumping onto the next batch of these. If a deposit will be required, that's fine by me. You seem trustworthy judging on how happy everyone in this thread is with their purchase. Looking forward to an update.

Thank you for doing this for the community

 

[aviphysics 9]

Would there be any interest in doing an american made batch? If there are enough of us in the US that are interested, it might be significantly cheaper than manufacturing and shipping from Europe.

This all assumes that Foehmsturm would be ok with that and willing to send details. If I were to setup the arrangements, I would plan to sell them for close to cost and be perfectly happy to send Foehmsturm royaltees, if he so desired.

 

[foehnsturm 969]

Of course I'm fine with that.

However, I have no details which I could send (and ask royalties for). Just look http://umforum.ultimaker.com/index.php?/topic/1611-fixing-pulley-innacuracy/?p=13534. There is just an empirically developed CNC program at workshop. Prices are mainly based on set-up costs and machine runtime per part, which is around 4 min on a CNC bush-type lathe.