I think this is directed to Bird, Tin or Geir,
Did you guys have any issues with your LM8UU bearings? My LM10UU bearings showed up yesterday (identical to "standard" reprap linear bearings but 10mm instead of 8mm) and of course, I quickly had them on my drill rods to start playing with them. They are chunky and simply don't slide all that well. I have found I can rotate them around the drill rod and find a "sweet spot" but what ever I do, the are just not that friction-free feeling I was expecting.
I don't know (and can't seem to find) solid information on if these guys should be lubed, if they are lubed etc. My assumption is that if indeed I were to add some goop to them, it would be white lithium grease, but I am wondering if I am going to make a mess of things.
Any thoughts?
Hi ChrisMy experience is
Hi Chris
My experience is only with the LM6UU for the XY-table and my findings are much the same as yours. The movement where jagged and not as silky smooth as I was expecting. My problem was probably more related to the low quality rods that I used and not the bearings them self.
I got some results by polishing the rods and added a small amount of oil.
The high quality LM8UUs that dgyver bought,
worked very nicely on the fancy rod that he bought with them. He is talking about purchasing some cheaper knock offs and trying them out with drill rod. He is looking to avoid the $50 or more investment in quality hardware just to make a smooth moving machine.
All I can say for now is the stainless(?) rod that he purchased to go with his bearings was very free and still is. Compared to the bushings that are on my table his machine is smooth as silk.
Thanks guys, I think you confirmed what was in my head
I was wondering about the drill rods…
I got mine from McMaster Carr and they were around $7 for a 3’ section (to be later made into a pair of 18" guides). The specs had them with a pretty good dia tolerance, +or- .013mm so I assumed they would be ok. In addition, when I got them they “looked” shiny. --The assumption is that if something looks shiny and pretty, it must be good, right? At this point, I wish I had gone with Bird’s suggestion above --simply getting higher quality SS rods.
Well, ok, here we are. I suppose I will take Mr. Andersen’s advice and see what I can do with the rods I have now. I have a drill press and I have a very good collection of wet/dry sandpaper going up to #8000 grit (I use paper this fine to sharpen chisels). I know for a fact that I can polish these guys up to a mirror if need be. I will chuck the rods up in the drill and see what I can do about smooth-a-fiying them.
It’s at least good to know I am not the only one with this issue, thanks.
