@Pᴀᴜʟsᴛᴇʀ2 - Yeah, I'm not sure either... I mean, I can see the linked to bearing are encased in a black metal case. I wonder if that prevents expansion or slight deformation of the plastic. He may have a point. Seems interesting, and I had not noticed them before. Obviously, the regular igus are better than the cheap metal bearing, but maybe these enclosed igus are a step above? Could be worth a punt? Although they are £11 each!!!
@Greenonline I have a reasonable amount of experience as I print my own bearings from POM. Indeed deformation is something that should be taken into account by the support structure, if the bearings are tightened incorrectly they deform and cause binding on the shaft. E.g. for this reason I designed this for my CoreXY printer
The left is the original that presses onto the bearing, the right has an extended flange and 2 screws inside the cylindrical holes take the load from the 8 mm steel shafts.
@0scar I've been vaguely surfing and looking into this whilst eating breakfast and I've noticed a couple of things wrt Drylin (1) Most of the applications linked to from the igus site do have the bearings encased in a metal holder (whether this is to simply hold, or whether it is to constrain under pressure, i don't know. See, for example, CNC engraving machine.
(2) There are thinner liners that are available, igus.com/info/…, that would require constraining, as they are very thin
(3) Looking at (2) the igus bearing that Paul and I were looking at (RJM-01) are substantially thicker, so I don't know if they do need constraining, but maybe constraining them would improved their performace, nevertheless.
(4) This page, overview shows the range of the drylin, some of which are encased, some are "naked", and some are described with the word "liner", which implies a replaceable inner, and possibly thinner, part.
@Greenonline In principle, the bearings themselves are not rigid enough to take the loads the could carry, hence encasing in alu housings. But, considering the forces we are talking about for our applications, I don't think that will be an issue. The biggest issue is deformation by assembly forces.
(5) In my blog, I wrote about RJ4JP-01, but I am not sure how they differ from RJM-01. I just got the model number from the ebay listings. I don't even see RJ4JP listed in the overview page.
I can now print in the living room without my wife complaining! :) My Anet A8 has Chinesium "Drylin" bearings, I could not get iGus Drylin affordable in The Netherlands a few years ago. The CoreXY uses POM on X and Y carriages. My new i3 Prusa will also use the self-made POM bearings.
Nice addition about the long bearings! that is exactly why I designed the long POM bearings, you then have no misalignment with respect to using 2 bearings!
@0scar - I've posted this question about the lubrification and immediately deleted it, so it is ready to be resurrected as need be, when you are ready.
@Greenonline - I commented back on your comment to my question ... the type I bought from Amazon was: RJ4JP-01-08
@0scar - In the Meta Answer you provided a link to the overall "Game Plan" question ... I've added the scope to it, as that's what it's about. It's the reason I didn't find it when I wrote the shopping question.
@Greenonline @0scar You two shouldn't encourage me so much ... it might backfire on you. I might start making all kinds of changes to the site, lol! J/K :o)
@Pᴀᴜʟsᴛᴇʀ2 - The more you do mate, the less we have to! lol :-) Seriously though, I really really need to move what is on that On-topic meta question, on to the On-topic help page. I just can't face it, or rather face starting to do it. I think that once I get started, that I will get quite into it. However, I know what I am like, and the On-topic page will probably end up being very very long and overly inclusive. And overly detailed.
@Pᴀᴜʟsᴛᴇʀ2, yes, I will probably need your expertise, I was thinking that myself... OK... Wow, it is night time already. 18:45... I starting messing about with an answer to that CD/DVD drive motor printer question at 16:00, or just after. Time flies when having fun, etc... Ok, I need to step back from the keyboard and do something, like play an Xbox game. Catch you all later, in a couple of hours maybe.
