Anyone can comfirm a 9mm pulley dimension?

I ask here cause its problably where must of those idler/pulley are used.

Im looking at robotdigg 9mm idler smooth (brass one) and toothed link and cannot find the right dimension. They said they use 695 bearing (13mm OD) in them, its impossible for the toothed (20 tooth = 12.10mm) so this must be for the smooth one but they have very limited dimension info.

Anyone have them and can comfirm the OD of the smooth one where the belt sit and the height of both toothed and smooth?

I write a email to them asking the right dimension but since they know for not answering must of the time I try to double my chance asking here too just in case.

I guess im force to take a break into designing the printer then, without those info its kinda hard to plan the alignment or bracket dimension to fit them.

When they say 9mm pulley, they are probably referring to the belt width, as opposed to the usual 6mm belt width.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

I know that, my design call for 2 meter belt so that why I prefer 9 over 6mm. I already have 2 meter long 6mm belt on my delta and know how tight they need to be, but for my next printer 9mm make more sense for the small price difference, but without the dimension I think I will be force to fall back to 6mm.

Since im planing to build 5 printer in a shot minimum I dont feel like ordering all the idler without knowing the dimension first or order a sample and pay shipping 2 time.

I suspect they smooth idler are 12mm height and maybe 15 or 16mm where the belt go

Does the size matter that much? If you're designing/building the printer yourself, get all the pulleys and design around them. There can't be more than a few mm difference in sizes of different pulleys. I don't know if you've used that type of pulley before, but they usually don't have spacers between the center rings, so you have to be careful not to over tighten the mounting screws (creates huge side load on the bearings), or make spacers for them yourself.

A pair of F608zz bearings makes a great flanged pulley for 9mm wide belt, and you don't have to worry about making spacers to fit between the bearings for each one:

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Shoulder screw 5mm are so rare and expensive even here in canads a metric country, so I plan of using 5mm smooth rod as a fix shaft so the preload will be light, washer on each side and 2 independent bracket sandwich the idler creating preload, but I thought about putting a spacer in the idler just in case.

I see lot of ppl using regular m5 bolts as shaft and I refuse to do that its not a good way to do it, on my delta I had some custom shaft made as shoulder screw with a flat and regular pulley runing on bearing block but it cost more and those printert I try to keep the cost down.
I wish I had a metal lathe...

I've seen a lot of machines designed with the pulleys mounted on studs/shoulder screws and as soon as the belts are tightened, the screws flex and the pulleys tilt.

In the setup in the photo I used M8 bolts with 50 mm long shanks. The bearings fit over them easily but they don't wobble because both ends of the bolts are secured by the rectangular aluminum tubing and nylon washers to take up the extra space between the bearings and the tubing. The rectangular tubing prevents the bolts from tilting due to belt tension, and the tubes don't tilt because they're secured with 4 screws at their bases.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

The problem using bolt m5 or m8 or whatever is they are not 5mm with the right tolerence (h6 etc) but always smaller causing the bearing to not be tight on the bolt and move under the belt tension. This is not a good solution in my book, im anal about precision, that why I had shaft made on my delta to match the bearing with tolerance. Im ready to lower my expectation with a 5mm smooth rod cause I want to cheap out a little bit (china bearing even) but not with bolt.

Its not about being supported or not, off couse you can support shoulder screw on both side too... Putting a m5 shoulder they usally m3 thread not supported on both side will bend I agree.

Robotdigg answer me.. Comfirming the 20 tooth use mr105 bearing and no answer about the dimension I ask...

For future reference on those pulley/idler I got an answer.

The height is 11.3mm
Smooth, belt seat D1 15.9mm, Flange D2 17.9mm
Toothed please refer pitch of 20 tooth gt2 pulley.