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Just wondering if any of the magnetic arm owners have come across creaking rods. It's almost like a switch was flipped on my machine. The thing was whisper quiet, then all of a sudden, most of my rods are creaking like rusty doors. It's like all the rods are too tight or something. I've got everything all lubed up, and when the rod is only attached at one end, it moves and spins just fine, but attach the other end to the cheapskate or the effector and suddenly it feels super tight.

Maybe the cups on the ends have all changed shape slightly from use? I'm a bit stumped. I don't want to print anything with the rods like that because it's a real pain to listen to.

Is it the rods or is it the cheapskates?

McSlappy wrote:Is it the rods or is it the cheapskates?

Definitely the rods.

You might consider a small dolop of paste wax on the balls.

I use Conservators Wax for stuff like this, Lee Valley carries it in the Great White North. This is a really pure wax that leaves no buildup on the surfaces.

nitewatchman

Maybe a dab of lithium grease?

I think nitewatchman's wax would work the best but in a pinch a small dab of bees wax or even white grease would probably work.
Some oils can deteriorate plastic that's why I like the wax solution better.

Thanks guys for the suggestions, but I would have thought the vaseline would have taken care of any binding if that were the case. Even temporarily that should have done something, no?

Tinyhead wrote:Thanks guys for the suggestions, but I would have thought the vaseline would have taken care of any binding if that were the case. Even temporarily that should have done something, no?

Yes, it should have made some difference. I assume it did not?

Geesh, if that was the only problem I had...LOL

Really though - that would drive me nuts too.

I have experienced intermittent creaking coming from ball joints on the cheapskate end of my Y tower. It's possible the plastic cups for the bearings have worn in to the point where the ball can touch the magnet. I've used no lubricants and it's only intermittent, so I'm ignoring it for now.

I've had other squeaking noises come from the cheapskates before when a screw was over tight and rubbing against the aluminum extrusions. This is different and seems less severe.

JohnStack wrote:Geesh, if that was the only problem I had...LOL

Really though - that would drive me nuts too.

Too late John.

barnett wrote:I have experienced intermittent creaking coming from ball joints on the cheapskate end of my Y tower. It's possible the plastic cups for the bearings have worn in to the point where the ball can touch the magnet. I've used no lubricants and it's only intermittent, so I'm ignoring it for now.

I've had other squeaking noises come from the cheapskates before when a screw was over tight and rubbing against the aluminum extrusions. This is different and seems less severe.

That's what I'm guessing at this point is that the cups have worn in enough to hit the magnet. It's just odd that it's affected more that one arm at once.

Ok. So I think I've figured out my problem and I was too dumb to realize it. I never put the connection together because I've been working my ass off the last week and haven't had much chance to get on the forums or do any printing, but just before I started that job, I had changed my effector plates for the stock end and E3D from PLA to ABS... and I had forgot I did it. I don't think I did any scale compensation for the ABS effectors... so now, the rods are just slightly closer together on the effector plate end, but this difference is causing the arms to fight one another as soon as it leaves position 0,0 - making it very tight and very creaky.

I found one of my old PLA effectors and tossed it back on and it sounds like a feather falling on a cloud. Any noise is completely gone.

I guess I'll put my PLA effector back into play for a few hours and print the cheapskate mounts out of ABS too. This should end up giving me the same separation distance again. I hope.

Outstanding!

Do you have any idea how much "slightly closer together" is? How much error becomes significant?

I want to start machining a set of arms and balls this weekend now that all the material has arrived. I plan on using 5/8" Class 100 balls, N50 Magnets, 1/4" Carbon Fiber Rods and 3/8" Carbon Fiber Rod End Sleeves. Should be very light and very stiff.

nitewatchman

nitewatchman wrote:Outstanding!

Do you have any idea how much "slightly closer together" is? How much error becomes significant?

I really don't know how much would be considered significant. Laying the PLA effector on top of the ABS, it looks like there is an overall difference of about 2mm on the longer edge. So the holes are probably at a difference of less than 1mm between the two materials. Just try and get your stuff as close as you possibly can.

Sounds like you've got quite the setup in mind for those arms! You'll have to toss up some pictures when they're done.

I am also interested in nitewatchman's setup and would appreciate some pictures.

Done deal.