Failing linear bearing/rail

[CriticalMass]

Nearly certain I have a failing linear bearing like Martin had. Right side Y is making a grinding noise and occasionally causing the belt to slip/jump teeth. Also what looks like rust being deposited on the rail. In addition to being poor quality, I think the linear bearings were not properly lubricated from the factory. However, there does not appear to be any grease fitting, not sure if there is a clever way to pack some grease in the bearings without removing it from the rail.

These are knockoffs of the HiWin, so I'm delving into a dumb experiment. I'm going to try some real HiWin blocks on the knockoff rails. Probably a bad idea since the tolerance tends to be very tight on these things. Will let you know my results when I get them.

[cbarkie]

Have you ensured that your rails are parallel to themselves in every plane? I had a similar issue and turned out one corner of my machine was higher than the rest.

[CriticalMass]

I'm sure it's off if you were to measure it on a small enough scale. However, I'm pretty sure it's within reason, it was an effortless glide before it had any operational hours

[CriticalMass]

Ok, couldn't stand waiting for parts to come in. Especially, when they may not help and I wanted to print some stuff this weekend. So I took the stock linear rails/bearings off.

When you turn the rail upside down you gain some access to the ball bearings.

At this point I put some gear oil on in the crevice and worked the carriage back and forth. Rinse/repeat

You can see on the napkin the rust I was talking about. (the gear oil is a honey color, not dark brown)
The bearings were starved for lubrication (I'm guessing the race in the carriage block was emitting the rust). When I first took them off and began inspecting them, often the balls on one side would not even recirculate when sliding the carriage.

So, it's been working most of the weekend now, not sure how long they will hold up

Hmm, these image uploads don't seem to work well. Edit: PNG's under 2meg seem to work

[Walter]

I gave them before mounting some drops of TriFlow. Even then they had some rust traces.
Now they are running smooth over one month now and not 'leaking rust' anymore.
I think that they are not well prepared in the plant (oiling/packaging) and that they not protected against moisture during transport.
Oiling them is just a good idea!

[CriticalMass]

Let's try with a smaller image

Ok, smaller PNG seemed to work. Not sure why it wouldn't take the other images, they would get to 100% then just pinwheel

[CriticalMass]

Definitely should be in everyone's assembly checklist. I've worked with many linear bearings, never had issues with ones that weren't lubed from the factory. Of course the ones I'm thinking about were THK or Misumi

[Martin]

Hey everyone, thanks for the hint with the oiling! Will do that on mine to hopefully extend the life of the remaining two original rails.

[csorrows]

With cheap Chinese motion assemblies it is always best practice to remove the crappy machining contaminated lubrication from them anyway. They just do not use much effort cleaning off machining debris before assembling and lubrication them. Plus the cheap grease they use is simply low quality crap. I use a thin lube like 3-in-1 oil to get most of the crap out then lubricate with a PTFE based grease.

[CriticalMass]

As promised I got the HiWin carriages and have installed them

Fun detail, the authentic ones have an actual grease port

Spent a good bit of time cleaning the rails.
The first carriage I tried fit perfectly on the knockoff rail. The second felt pretty tight, but once put together the assembly felt subjectively smoother than before. Sounds better too, but I suspect that owes more to the PET gantry brackets I installed in place of the melamine ones.

The set of 3 set me back $88

Haven't got around to installing the X carriage yet. The system is running as I type.

[Walter]

It's a whole difference when they put their name on it!

[CriticalMass]

Cross posting thing in this thread too

Since I am one of the few people with extra carriages and shipping inserts. I made a model of the shipping insert for the carriage. The carriages that came with the printer (mine anyways) have wires that should retain the bearings in most situations if you are careful.
http://www.thingiverse.com/thing:1972859

[Troy_Rutledge]

I have a question...
can this part be ordered form someplace? I have one that leaked a ton of tiny silver magiks tonight and can not find them all to even begin trying to put them back in. I sent a message to Folgertech but if they are not high dollar I would not be opposed to buying another so the wait will not be for ever and day trying to get a replacement for the one holding me up. Any help would be mucho appreciated, thanks in advance.

[PaulS]

try this, looks like lots of parts for ft5 not sure about teh exact 1 you are looking for but
http://www.thingiverse.com/search?q=ft5&sa=

[Troy_Rutledge]

thank you but i need machine parts, yet to get it all up and running to print any yet.

[PaulS]

i believe they offer print services as well but never tried it. Anyone have experience with that? My printer will be here Saturday so i am in the same boat!

[CriticalMass]

Which part are you asking about? The linear bearing carriage?

I am going to assume that you are asking about the cart. The knockoffs can be found on amazon and ebay. The only place selling the authentic HiWin parts that I found in the US is a vendor called "Motion Constrained" who also sell on ebay. Searching for MGN12H will find both the HiWin and the knockoffs

[Troy_Rutledge]

I went with amazon, it has shipped and am looking to getting back to work monday.

[Martin]

Quick update on my rails: After the fifth purging with oil (now PFTE) I still get messed-up paper towels. The amount of brown gunk that sits inside these carriages is unbelivable. At least they seem to last with that kind of lubrication.

[dimeusa]

From the second item I printed I have been having an intermittent problem with my FT5 where it would randomly offset a layer. Over the last several weeks it has been getting worse. I checked the rails numerous times and they have always seemed free. Yesterday I started to see debris under the rails. I disassembled everything and found I had the same problem with the bearing. They did not seem to stick in the same spot each time, it was random over the length of the rail. I did a quick search and found this doc about oiling /greasing the rails. http://www.intercom.si/web/dokumenti/HIWIN_LI_EN_V1_1.pdf
The doc is on the real HiWin bearing but I think it may help others. I just used WD40 to flush them, have everything moving smooth now. I guess this is going to be a regular maintenance item for this printer. Hey one thing in this doc is that the oil port shown on the real units, this doc says you can add them by just hitting the spot with a poker. I don't have a spare set of bearings to test this on, so I'm not going to try this at this time.