correct belt dimension??? 300mxl or 240 mxl ?

[italianmaxx 0]

I'm building my UM, just finished step 3(the hard one) but I found the belt very very loose :evil: . UM dispatched me four 300 mxl belts, but in the videos (correct belt tension) and in the forum I found that on UM are installed the 240mxl.

wich are the correct one??? with my loose belts i thing that the thingiverse tensioners wouldn't be of any use. I tried with a clothes spring and it works but I dont want a 2000K $ machine run on spring clothes...

and where to find 240xml belts?

thanks!

[c-ernst 1]

Interesting thing about the belts, the ones that came with my machine were marked 240mxl so I ordered 240mxl belts. WAY TOO SHORT, by like 2 inches. I don't know if there is such a thing as metric and imperial belts or what.

I ended up ordering a set of 300mxl, 297mxl, and 295mxl from this company B7B manufacturing.

300s were too long and the 295s were just a tad too short. Ended up with the 297s

Got them from here:

http://www.bbman.com/

product page:

http://catalog.bbman.com/db/service?dom ... 297MXL025G

 

[italianmaxx 0]

After a lot of search and an email from ultimaker support I am sure they send 300mxl belts. almost all people use some kind of belt tensioner, fom a simple clothes spring to some tensioner found on thingiverse. I think a 2000 € machine MUST work out of the box, but maybe not all people agree with me... Anyway i finished my UM tonight, the belt are slack and loose but better than yesterday after a lot if tweaking. I am going to print some belt tensioner from thingiverse asap, but in the duture i will try 297 or 295 mxl belts.

Thanks 4 your reply and your link.

[joergen 2]

After a lot of search and an email from ultimaker support I am sure they send 300mxl belts. almost all people use some kind of belt tensioner, fom a simple clothes spring to some tensioner found on thingiverse. I think a 2000 € machine MUST work out of the box, but maybe not all people agree with me... Anyway i finished my UM tonight, the belt are slack and loose but better than yesterday after a lot if tweaking. I am going to print some belt tensioner from thingiverse asap, but in the duture i will try 297 or 295 mxl belts.

Thanks 4 your reply and your link.

your research, and your emails with the UM, did it clarify WHY the belt has printed "240MXL" on it, when it's an almost 300MXL in reality? I mean, the manufacturer doesn't print 240 on something that is a 300 (which refers to the number of teeth I would say), and a 240 is simply 5cm too short... and it's a closed loop, so how can this happen?

[italianmaxx 0]

I found some producers naming belts by th eteeth and others naming belts by the lenght in inches. So a 240 mxl could be a 240 teeth or a 24 inches belt. Most of the use teeth numbers so 300 teeth x 2,032 = 609.6 = 24 inches or 240 mxl = 24 inches = 300 teeth. Different producer, different name , same belt.

That can't explain why on theum you have a 300 but you actually need a 297 measuring circa 6 mm short. So better print a tensioner as soon as possible...

[c-ernst 1]

Actually I have a correction I bought 298mxl belts also. So on my X axis I have 298 on my Y axis I have 297. Call me ocd but the tensioners really started bugging me so I did the tentioning (real word?) through swapping out the belts.

They are absolutely perfect now in tension.

[clem 0]

I'm going to replace the belts on my ultimaker. I haven't met the minimum order at bbman, anyone know the specs for the drive belts (the shorter ones)?

[thedudevt 0]

Mine says 80MXL on it FWIW... I ordered some from McMaster-Carr on Monday, we'll see if they fit. I ordered 64MXL per a post on this board last week and they were too small.

[igull 0]

Hi

FWIW, I'm scratch building an Ultimaker and eventually managed to figure out the MXL sizing conventions ...

The ultimaker has 2 MXL belt types (MXL belts are imperial pitch - 0.08" - 2.03mm).

The 2 belts are 300 teeth and 100 teeth - therefore 300 x 2.03mm = 609

mm or 23.976 " - to confuse the simple minded, they are marked 240 MXL - 24.0" :smile:

The 100 tooth belt is 203mm or 7.99" - marked 80MXL - 8.0"

The pulleys are 20 tooth MXL - I couldn't get 8mm bore, so just bored them on the lathe to 8mm and 5mm.

The belts I have seem to fit perfectly to the ply framework I cut from the thingiverse data (for now at least :smile: ).

Cheers

Neil

 

[calinb 11]

It seems like the 297 mm belt (297MXL025G) is probably best for an Ultimaker Original. My long belts are getting long enough that it's becoming difficult to take up the slack with my clothespin spring tensioners so I'm planning to order new long belts from B&B. The minimum order is $35 and they also offer a discount for 10+ quantities of the same belt SKU. If I order three long belt sets (12 belts), the price works out to $19.92 / set total. (Including the B&B shipping and handling charge of $10.07).

If anyone in the U.S. needs new belts, I could package a set or two in a $5.95 USPS small Priority box (which includes up to $50 insurance) and mail them to you. At $25.87 / set, you'll be out of pocket about $20 less vs. placing a single set order with B&B. Please PM me before the end of this week (August 23rd, 2014), if you are interested in a replacement set(s).

-Cal

 

[InfiniTTTy 0]

It seems like the 297 mm belt (297MXL025G) is probably best for an Ultimaker Original. My long belts are getting long enough that it's becoming difficult to take up the slack with my clothespin spring tensioners so I'm planning to order new long belts from B&B. The minimum order is $35 and they also offer a discount for 10+ quantities of the same belt SKU. If I order three long belt sets (12 belts), the price works out to $19.92 / set total. (Including the B&B shipping and handling charge of $10.07).

If anyone in the U.S. needs new belts, I could package a set or two in a $5.95 USPS small Priority box (which includes up to $50 insurance) and mail them to you. At $25.87 / set, you'll be out of pocket about $20 less vs. placing a single set order with B&B. Please PM me before the end of this week (August 23rd, 2014), if you are interested in a replacement set(s).

-Cal

 

How did you make out with the 297MXL025G belts? I too JUST got in replacements for my Ultimaker Original and they are indeed the 300 MXL belts which are too big (by a hair). The original Ultimaker instructions were clear about making sure they were tight.

I got this response from the supplier support team:

"We do have the same thing on our UMO, that one of the belts are not as tight as the other belt (not drastically but a bit of sagging). When we brought it up to support about the issue, we were told that it was normal and could get a tensioner but didn’t need it. After 2 years, turns out they were right since the belts don’t stretch and are notched, things have been working fine even without a tensioner. "

Hoping for some direction here. Thanks!