Replacement pulleys for UM2?

[3dnerd 6]

Hi,

I found out that the pulleys of my UM2 are not centered and the axes.

It seems the inner diameter of the pulleys is a littlebit bigger than the diameter of the axes.

Since there is only one screw in the pulleys there is no way to center the pulleys.

If I move the print head by hand I can hear a different noise every 360 degree of the pulleys. Something like 'weeeeeweeeeeweeeee'.

Since I still have problem with not touching top layer I want to replace them completely.

- Are there any UM2 pulleys available which fit better onto the axes?

- Could you recommend any?

- What is the correct name of the pulleys?

- Do I have to replace the belts as well?

- Does anybody have experience with replaced pulleys on UM2?

Thanks for any help...

[3dnerd 6]

Hi,

I don't want to push - 73 user read this post but nobody can give me any recommendation or tell me some experiences?

Did you check if your pulleys sit centered on the axes on UM2?

What do you do if they are not centered?

[tommyph1208 55]

Hey

You can find all the parts of your UM2 on GitHub:

https://github.com/Ultimaker/Ultimaker2

The pulleys you are looking for are 20 teeth 2GT (or GT2) pulleys with an 8mm. bore, - The UM2 uses both single and double ones, ie.:

https://github.com/Ultimaker/Ultimaker2/blob/master/1166_Timing_Pulley_8mm_Shaft_GT2_(x8)/B1166-B2P-B.pdf

and

https://github.com/Ultimaker/Ultimaker2/blob/master/1167_Timing_Pulley_Double_8mm_Shaft_GT2_(x1)/B1167-B2P-A.PDF

They are available from many many sources and vary greatly in quality, so if you are replacing them in hopes of getting better performance, you probably want to go with something like misumi or similar, rather than cheap chinese ones from ebay or aliexpress.

You should be fine with the belts you have (unless they are worn)

Edited May 23, 2016 by Guest

[3dnerd 6]

Hi tommyph1208,

thanks for reply, that helped me to go one step further ;-).

You said 'misumi or similar'. Could you tell me what you mean with similar?

Do you know brands which produce high quality pulleys beneath Misumi?

What about the UM2 dual pulley - who provides this one in good quality?

Thanks again...

[tommyph1208 55]

Hi tommyph1208,

thanks for reply, that helped me to go one step further ;-).

You said 'misumi or similar'. Could you tell me what you mean with similar?

Do you know brands which produce high quality pulleys beneath Misumi?

What about the UM2 dual pulley - who provides this one in good quality?

Thanks again...

 

I'm afraid I can't really help you with specific vendors, the only GT2 pulleys I myself have bought (for other projects) have been the previously mentioned cheap chinese ones...

I would generally say that you get what you pay for, so if you find some expensive ones somewhere they will be better... Be careful, and evaluate the shop though... Sometimes the price difference is mostly markup for the guy who owns the shop, and they end up being in fact the exact same ones as the china ones.

I have not had any problems so far with the ones I have gotten form eg. ebay (and even if one out of a batch of 20 is bad, I just throw it away), I am not that picky though...

[3dnerd 6]

Hi tommy,

thanks anyway.

I contacted Misumi already but they sell only to business partners and not to private persons like me :-(.

Does anybody know where to get Misumi pulleys (especially the dual one) as a private person in Germany or Europe?

What other brands are known to provide best quality pulleys?

[tommyph1208 55]

Maybe RobotDigg?

http://www.robotdigg.com/category/9/Timing+Pulley

Edited May 23, 2016 by Guest

[3dnerd 6]

Hi tommy,

thanks - I already found this shop yesterday as well using Google.

But since it is located in China I doubt about the quality.

They offer also the dual pulley, but I know neither the brand of the pulleys nor the quality.

I also have no experience ordering goods from outside Europe.

What about customs clearing and fees etc?

Edited May 23, 2016 by Guest

[neotko 1,417]

You could send an email to http://www.technobotsonline.com o http://www.makertronics.co.uk/ they are the same company and maker has gt2.

I bough from them a z pololu nut and bearings and all was very high quality. It's very hard to find europe shops that don't sell just bad brandless china stuff.

[tommyph1208 55]

Hi tommy,

thanks - I already found this shop yesterday as well using Google.

But since it is located in China I doubt about the quality.

They offer also the dual pulley, but I know neither the brand of the pulleys nor the quality.

I also have no experience ordering goods from outside Europe.

What about customs clearing and fees etc?

 

I think customs rules etc. differ from country to country... I live in Denmark, and we have a minimum threshold of 80kr. (around 10 euros), below which packages are disregarded as far as customs are concerned.

Above that it gets really expensive with up to aroun 35% of the price added + a 20 euro handling fee...

Edited May 23, 2016 by Guest

[StephanK 30]

What about customs clearing and fees etc?

 

Since you seem to be in Germany like I am:

None if the total amount incl. shipping is below 22,00 Euros.

Between 22,00 and 150,00 Euros you will be charged 19% tax

above 150,00 Euros you will be charged 19% tax & customs duty on top. I got no clue how many % that might be for pulleys from China.

[neotko 1,417]

I don't know how it's in germany but I never got taxed from an import unless I buy using ems/fedex/ups. Using normal delivery I never got taxed.

Edited May 23, 2016 by Guest

[3dnerd 6]

Hi,

thanks to to all.

Did anybody buy from RobotDigg or does anybody know who is the manufacturer of RobotDig pulleys?

What else brands are available (Europe or Germany) which provide high quality pulleys?

[kaasplank 2]

I've bought pulleys from RobotDigg before and they were good quality. I believe they produce them themselves. Of cource you could buy pulleys from SKF or other big brands but they are far more expensive and they dont have the double GT2 20 pulley.

[gudo 246]

" Something like 'weeeeeweeeeeweeeee'.

Since I still have problem with not touching top layer I want to replace them completely "

Hi to all, hi 3Dnerf

The ends of diameter 8 shafts are centered with flanged bearings

even if the pulley is not well centered, at least initially, it should not have a great impact on the layers height , the noise makes me doubt ...

may be you should check the flanged bearing on the defective pulley side and if its seat has become oval following the pulley centering problem.

[3dnerd 6]

@gudo: thanks, just to make it clear the 'weeeeweeeeweeee' I can hear if I move the head with my hand. Each 'weeee' exactly follows one turn of the axis. I normally would expect a 'weeeeeeeeeeeeeeeeeew' if I move the head from front position to back position. But it is not it is this 'weeeeweeeeweeeeweeee'.

I don't have problems with layer height. I have problems with not touching top layers. If I take a close look at my top layer there are regions which are closed like expected. But a few milimeters before or after the lines ar not closed they do not touch and small gaps appear. This is repeatable so if I print again then the gaps appear always at same position on the printbed.

Then I measured the diamater of the string coming out of the nozzle using a digital caliper and it has a diameter of only .35 instead 0.4. Reducing the nozzle size setting in Cura from 0.4 to 0.35 improved the top layer quality already significantly.  But still there are gaps here and there.

I assume this has mechanical reasons. Not centered pulleys cause the head move a bigger or smaller distance and not a homogenous/linear distance which I think could be the problem. If two or more pulleys are not centered then the error will sum up further.

Edited May 24, 2016 by Guest

[ultiarjan 1,223]

I assume this has mechanical reasons.

 

Did you check if your xy axis are straight? if not I would advice to check this.... the new xy axis in the upgrade kit solved it for me...

[gudo 246]

Hi, thanks !

Ok ! I see

[3dnerd 6]

@ultiarjan:

Do you mean the 6mm axes where the head is mounted on or the 8mm rods?

And how can I check if they are straight and not bent? Just take a look?

Thanks...

[ultiarjan 1,223]

The 6 mm xy. Just take them out and roll them on a flat surface like a stone kitchen top. For mounting/unmounting have a look in the manual from the um2 upgrade kit. Download in the manual section on this site.

[3dnerd 6]

Hi ultiarjan,

thanks, I checked the xy axes now and they are completely straight.

I got some new pulleys now and coming weekend hopefully I will find some time to exchange the original ones.

Is there anything to consider before I replace the original ones?

E.g. what I have to consider to not damage anything?

Thanks for any experiences you can share...

[ultiarjan 1,223]

https://fbrc8.zendesk.com/hc/en-us/categories/200131460-Installing-Parts

Think this will help you...

[3dnerd 6]

 

@ultiarjan: Thanks I will take a look and hopefully I will be best prepared for the surgery ;-)

[3dnerd 6]

Hi,

I wanted to start now to replace the pulleys and found out something more.

On moving the printhead by hand I could see one of the Y-shafts (Part-No. 1011 8mm x 348mm) is not straight. The sliding block moves up and down a littlebit so I think I heave to replace it as well.

Can I get one directly from Ultimaker company?

If not does anybody know where to buy one?

Thanks...

Edited May 28, 2016 by Guest

[ultiarjan 1,223]

you can get them from UM re-sellers, so in your case try Igo3D