Source for 8x11x30mm sintered bronze sleeve bush(ing)

[anon4321 16]

Anyone know where someone in the US could source the 8x11x30mm sintered bronze sleeve bush(ing)s used in the XY blocks?

I want to print a second set of XY blocks and kept the originals intact.

 

[callum-burns 0]

The only place other than Ultimaker to buy them ready made was aliexpress. Arrived perfect!

[3dguy 0]

I have been searching for the same things lately and I have found a few bearing companies in the US and Germany but none that have the 8mm x 11mm x 30mm bushings, I have found some that have 8mm x 11mm x 25mm in bronze, and 8mm x 11mm x 20mm and a company that makes custom bearings but I do not have any idea what they charge for the custom work.

http://asbbearingsonline.com/

http://www.symmco.com/metric.html

and 8mm x 15mm x 24mm aluminum, lined bearings from PBC

http://www.pbclinear.com/FJ-JIS-Closed-Linear-Bearing?tab=Specifications

and 8mm x 15mm x 24mm and 8mm x 16mm x 25mm from

http://www.igus.com/wpck/3542/DryLin_R_Lineargleitlager

The bushings don't have to be the same length if the part is slightly redesigned they just need the same diameter.

IGUS's prices aren't the cheapest , they cost more than bronze by quite a bit.

oh, and aliexpress as Callum Burns noted. They have quite a few available through vendors in China at really inexpensive prices, though I do not have a clue about their shipping charges.

http://www.aliexpress.com/wholesale?SearchText=Ultimaker+8mm+bushings&catId=&initiative_id=SB_20140622000930

 

[anon4321 16]

I wonder how important the length is... The obvious important dimension is the 8mm ID. The OD is less critical as any custom XY blocks could be adjusted to 12-14mm OD.

There looks to be approx. 5mm extra on the length in the standard UM blocks. Obviously, a shorter bushing could work.

However, I wonder if it would allow more angular play. Or in other words, would shorter allow the smaller axes to deviate from 90 degrees more than the 30mm versions?

Since the smaller rods are driven at both ends, does it matter?

 

[anon4321 16]

3dguy, I think it hit most of those links. Thanks, I'll relook at them.

 

[3dguy 0]

I don't think it will matter. I could see it making a difference on spans much wider than 12 inches. I will probably find out in the next week or so as I opted to go with linear bearings that are almost 1" shorter than the ones that are currently on the z-stage for the aluminum stage I am trying to implement. If it doesn't provide the need stability then I will have to order the longer 2"ish bearings.

 

[jonnybischof 60]

The length of these bushings shouldn't matter "much". I have the same problem atm: Misumi only has 25mm long bushings. I am going to use these though, because I think that it won't matter.

Longer bushings keep them from "twisting" off the axis (difficult for me to describe, I hope you know what I mean). But that isn't necessary, as the rectangularity of the X-Y gantry is given by the X-Y belts and shafts. As long as these don't allow for any deformation, there won't be a problem with the bushings getting out of alignment.

So it shouldn't be a problem to use slightly shorter bushings.

 

[anon4321 16]

Hey Jonny,

I think you modded or built a UM1 with upgraded 8mm rods (for direct drive).

Did you get the rods from Misumi? If so, what are the part numbers? And what tolerance bronze bushing did you use?

 

[jonnybischof 60]

I'm still building, but yes, I get pretty much all the hardware from Misumi. You know you get the very best quality there. Don't mention the prices though...

Part numbers for the shafts: RSFJ<diameter>-<length> (These are with LTBC coating which is expensive but mostly cosmetic).

SFJ<diameter>-<length> is the standard shafting.

I used g6 tolerance which is what they recommend to go with their linear bearings and bushings. There is "some" tiny amount of play with the linear bearings, but they move with almost 0 resistance. Nothing like the UM original stuff.

Bronze bushings: SHBR8-25

I don't have these yet, but will get them with the next order.

You should take a look at their flexible couplings: CPSX19-5-8

Insane price compared to the chinese stuff, but they are also "a little bit" better than these

Most importantly, they do not allow for any little bit of torsion.

 

[anon4321 16]

Jonny,

Did you ever install the LTBC rods? The coating on the ones I'm using is slowly wearing off.

Have you experienced the same?

Should I care?

 

[jonnybischof 60]

I've also noticed that the LTBC wears off over time. Maybe it's not meant to be used with bushings? I don't know...

It shouldn't matter though, as the LTBC is only a few microns thick (if even). I'm buying the hard chrome plating (HV750) now. Haven't used any of these yet... Maybe non-plated is actually the best thing to go, I'm not an expert on these things o.O

 

[tommyph1208 55]

E3D sell 15mm. versions at 1£ each... You could just place two next to each other if you want...

http://e3d-online.com/Mechanical/Motion/Bronze-Bushing-for-8mm-Rod

 

[anon4321 16]

I went with the full misumi solution, rods, bushings (25mm) and couplers. I also switched to direct drive and GT2 belts plus the twisterblocks.

Everything is very smooth and positioning seems very precise.

Oh and I updated to the UM heated bed kit.