How to assembly right?  

RE: How to assembly right?

The correct screw is indicated with dimension and length in the text next to the image. Just follow the instructions and it will be right.
If you select a screw that is too long, it may cause problems if it collides with other parts of the printer.

RE: How to assembly right?

so how to know which one i should choose from?
the page is not that good when it come to such thinks.

RE: How to assembly right?

@prusaprinters-profile

Use a ruler or micrometer and choose the screw based on the deminsions.  The instuctions are quite specific and you cna measure them to determine which ones to use.  

RE: How to assembly right?

There should also be a stocker on the front of the bag that the screws came showing the screw sizes. Those images are actual size. Place the screws next to those images to work out which are which.

RE: How to assembly right?

I am damn pissed! I try over 1h to assembly that sshhhttt....

https://help.prusa3d.com/de/guide/2-zusammenbau-der-y-achse_165798

Stepp 34

Its impossible to mount it. The Belt is way to short!

RE: How to assembly right?

@prusaprinters-profile

The Y-axis belt should be approx. 650-660mm long. On my MK3 I had to cut off a few cm. I think Prusa has supplied you with a too short part -> Prusachat or, if it should go faster, buy it here -> Gates GT2 6mm

RE: How to assembly right?

One of the belts is longer than the other. Have you used the right one ?

RE: How to assembly right?

I use the "Belt Y".

RE: How to assembly right?

I wonder it you got the wrong belt.  It took some finagling but I go it to fit.  

RE: How to assembly right?

@prusaprinters-profile

Too short belt can sometimes happen, but what the heck. I would report this to Prusa! Just log in with your Prusa account and select the eshop. After a few seconds the chat window should appear on the lower right corner. If the chat window does not open, disable a possibly activated adblocker or try another browser.

RE: How to assembly right?

@karl-herbert

Concur.  Complaining on the forum will not get you what you want.  It might get you an answer, but a replacement will have to come from chat.  

...

Hey everyone!
Sadly I dont have to mode to finish the build. Is there someone who want help me via Skype to get them ready?
Thanks

Belt length depends on the item being assembled properly

I would not let someone who cannot determine the difference between two screws assemble my printer.  Perhaps you need more practice with mechanical assembly.  Given you were not able to figure out which screws were which, I'm assuming the assembly is going poorly and different parts are being used than were intended per step (even though the step-bagging makes this difficult, some parts look similar across steps) ..  If the wrong parts are being used for getting the Y axis ready, the belt has no chance of being able to fit.  

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Well I have some problem with the eye sight.

It's probably the correct belt

Things that impact belt length at the final step are inserting the belt at the first step.  Getting the belt carriage on backwards will also create misfit issues.  That's an easy one to mix up.  The belt provided on both of my MK3S builds was JUST ENOUGH - so you have to be pretty precise and follow the pictures in the on-line assembly manual very closely.  While I appreciate that someone with limited eyesight would want to be able to build their printer un-aided, it's a pretty expensive project to have to not be able to get it built.  I'd suggest getting a mechanically inclined, detail oriented person to assist if you can.