[Closed] Bearings: RJZM-02-08 appears to be a good alternative?  

Re: Bearings: RJZM-02-08 appears to be a good alternative?

What irritated me about RJUM-02 was the following quote from the spec sheet:

"Secured by pressfit in recommended housing bore"
http://www.igus.com/wpck/3661/drylin_r_rjum_02

compared to RJUM-01:

"Secured by retaining clips according to DIN 471 or 472"
http://www.igus.com/wpck/3663/drylin_r_rjum_01

Re: Bearings: RJZM-02-08 appears to be a good alternative?

Thats why I will stick with sheathed bearings as I described. I'm not comfortable with a zip tie being used for creating the squeeze. The ones I mentioned are already set in a housing. The RZM-01-08's are also like this, but they are 16mm OD and while Ive already looked at and tested the modified parts to accommodate this, I prefer a drop in replacement with no mods to the original MK2 parts, for now.

As for press fit, thats a term loosely used too much on their site- all it means is a way to secure the bearing in place.

Re: Bearings: RJZM-02-08 appears to be a good alternative?

Exactly why i used RJZM-01-08 for the y-axis, encased and no mention of press fit. (The extra 1mm didn't matter there. Z-axis was a different story, thats why i went with RJ4JP there).

However, for RJUM-02 the spec sheet clearly states pressfit required despite being sheathed. Which in itself seems to me a tad contradicting. I guess somebody needs to order a set and give it shot.

Re: Bearings: RJZM-02-08 appears to be a good alternative?

The sheath on the one is smooth, hence press fit, vs the RJZM-01-08's having clip channels/retention on the housing. Thats all. Like I said, its a loose term they use on the site and it can be misunderstood as requiring outside pressure like the bare bearings (the cheapy $1.99 ones, in comparison)

Re: Bearings: RJZM-02-08 appears to be a good alternative?

RJZM-02-08 seems ok to me. Didn't notice them before.
Anyway, I still think that for Y the best option is RJZM-03-08 with fixed mounts.

Re: Bearings: RJZM-02-08 appears to be a good alternative?

The sheath on the one is smooth, hence press fit, vs the RJZM-01-08's having clip channels/retention on the housing.

Oh, you're right. That does make sense. I didn't notice that before. Would be kinda hard to use the standard clips without the grooves.

Re: Bearings: RJZM-02-08 appears to be a good alternative?

The "press fit" into a "receiver" is required to get the internal size or bore correct for the bushing.

Re: Bearings: RJZM-02-08 appears to be a good alternative?

Sorry about the late reply. I got three RJZM-02-08 during my MK3 assembly. I put them under the heated bed. Worked great. Even made a comment in the instructions page.

Re: Bearings: RJZM-02-08 appears to be a good alternative?

My Prusa MK3-

I am unsure what the big deal is with using these Igus plastic bearings. I understand the Prusa supplied linear ball bearings are lower quality and have caused problems but I have seen many unsatisfied results on YouTube and forum postings using the Igus plastic bearings. These non-metal cased Igus bears are designed to be pressed into a bore to collapse and hold the bearing in the part and slide on the recommended rod with the proper tolerance. Without the press fit the Igus bearing will run loose on the rod and make things worse than the Prusa bearings. They wear out quickly when not used with the recommended rods and the cost for a conversion quickly mounts in expense.

In my case I researched the Misumi linear ball bearings that I later purchased four via a company setup purchase and have been more than happy with the results. I used them on the X-bed frame only because the bearings had a good close tolerance fit for the Prusa slide rods. I added some Super Lube grease in the bearing before installation and will use these bearings for future replacements. the Prusa bearings are performing just fine. I added Super Lube grease to those Prusa bearings before installation as well. I also spent more time on installing the bearings and making sure the rods were well aligned and movement was as easy as possible.

Re: Bearings: RJZM-02-08 appears to be a good alternative?

Sorry about the late reply. I got three RJZM-02-08 during my MK3 assembly. I put them under the heated bed. Worked great. Even made a comment in the instructions page.

What is your experience with them since you installed them?