Does anyone have a definitive fix for a loose motor coupler? It’s loose on the lead screw side. So far I’ve tried High strength loctite, wrapped tape around the turned end of the leadscrew to widen the diameter a bit, and most recently widened the slot to get a little more clamp out of it. All have eventually slipped. I emailed support originally and there solution was to “crank on the cap screws really hard.”
I can definitely see that there is no gap on the screw side…but a gap on the motor side…good picture by the way.
Have you tried to flip the coupler around?
I would consider putting some small grooves in both the coupler and on the screw shaft…then by adding a little metal shim you might gain some traction…
one other thought…do a measurement with calipers of the shaft size of both sides…post the diameter you get…you might have a possible improperly milled screw shaft…
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Did you use bearing retainer loctite or regular loctite. The bearing one is meant for larger gaps, I believe the 660 version will fill the larger gaps (to 0.02"), LOCTITE 660 - Retaining Compound - Henkel Adhesives
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The coupler should definetely not be fully collapsed around the stub end of the lead screw. Can you confirm that the stub end should be 1/4" diameter? Likely that is it undersize which is causing the problem.
I just measured the stub ends of both lead screws and the left is undersized. Do I need a new leadscrew or do you recommend another solution?
Sendv5ge pictures to the suport email . I have a feeling you will be getting a new drive shaft.
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Yep, that is a mistake, send an email to support and we will send you a new lead screw.
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I just ground a flat edge on all my ends, motor and lead screws. When the X axis is at far bottom corner of table, that is when it would slip the most. Got sick of it so decided to take them all apart and grind flats. Kinda like a drill bit, when it slips you need to make a flat on it. I’d do that when your new lead screw shows up.
How does that prevent slipping if the mating surface of the coupler is round? Did you drill and add a set screw to the coupler?
Because two round surfaces don’t make right. One needs something to bite on. If one has some grip than it lessens the chance of spinning out, just like drill bit in a drill. If its round it wants to slip and push into the drill, but if you grind a flat on it the drill has a better bite. Thats what I did and I haven’t had any Z slippage. The X was the real culprit. I just got new bolts today bc I had one head stripping. I ran the setup today and had no slippage. So now all my lead screws and motor shafts have one flat edge. Its just what I did, you don’t have to try that.
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Hello from the Czech Republic, I solved the problem with loosening the screw coupling by centering the screw so that it is not bent (I had a bent screw), then I tightened the screw at both ends and finally tightened the middle assembly
Hi…the couplers I utilize that are mounted on a shaft with no level and so forth, have a twofold set screw at 90°, you could generally bore and tap another, yours coming from China they are destined to be measurement.
The name depends where you get them from, set sinks N.A. Grub tightens UK.
I got the sharp ones in the couplers I bought.
I just ordered some of these from Ruland. Iv since fabbed up my own while waiting on these. My supplied ones were killing me on the X axis. I ended up stripping the coupling too. So these should def help.
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How can I order one of these?
I got em off ebay, prices are all over the place but well worth it type in Ruland Manufacturing Clx-4-4-F Coupling, One Piece, Bore Dia 1/4 In, and or part of that and see what comes up. Id say $25 to your door is a really good deal, sometimes these are 30-50 bucks.
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Thanks. I’ll check those out. I installed the new lead screw that LS sent me and the coupler is holding tight for now but is pretty beat up from me modding and trying to make it hold these past 9 mos. I found a few on Amazon but these Rulands look like much higher quality.
I ordered another cheap one off ebay that is aluminum but has set screws on opp sides of each other. Got it just incase, it was dirt cheap. But yes I think this is going to be the best one there is. Iv notice the farther out from the motor the more likely it is to slip. Also I notice in same area when zipping around at 300IPM my lead screw will vibrate, sometimes making noise. So I think that effects it coming loose too. Gotta really make sure the lead nut isn’t off center also.
@num1husker, @directioneast Were you guys able to to get the Rulands to work. It was a total fail for me! I bought one to replace my mangled coupler but stripped two of the screws while tightening and another of the screws threads stripped internally. They are really small and can’t take much torque. I think I’m gonna contact Langmuir and see if I can get another stock coupler…
