Confirming bad zaxis motor

I have noticed that when my zip axis motor goes up and down it sometimes catches and sometimes doesnt. You can here it grinding so I know it’s sending power to it. I think just doesn’t go up an down smoothly like it used to

See if your pulley set screw has come loose.

Nothing I even backed it to reset it and still does it

When the power is turned off, can you turn the top of the threaded rod easily by hand. It will take a lot of turns but you should be able to move it the full travel length up and down by hand. If not you may have something binding.

Something with the rod and that stupid little plastic piece that holds the spindle bracket on. I was free spinning like you asked and it got really hard in some places so I guess I’ll be ordering a new acme screw and plastic thing. Which I shouldn’t have to cause this machine is less than 3 months old

We will see what happens I have 2 cnc machines a piranha fx and and an xcarve and they both failed on me

When you assembled it, did you run the delrin nut up and down the acme screw 20 or 30 times to bed it in ? Most peoples have some tight spots until they do that.

No no I didn’t why would I have problems now with it after 3 months and using the machine almost on a daily basis

This certainly isnt enough to write off the entire machine and chuck it out the door. These are quite complex devices that can be a bit temperamental at times and occasionally need care and feeding or a good spanking. You say you have been using it daily, by no means is this a set it and forget it forever type apparatus.

MIne was glass smooth at first too. Ended up taking the acme screw and delrin nut apart, cleaning them both, and reassembling them with a dose of PTFE dry lube spray(about 5 bucks at home despot).

I can still hear it tighten up a bit as the screw rotates but it does not bind to the point of stalling.
I suspect that stupid fine wood dust migrated into the threads enough that it was starting to bind.

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I rarely have cut wood with it the past week or so I cut mainly acrylic. I understand things need to be adjusted from time to time. Just for some reason it decided to screw right then and there I could make it go up and down fine and sometimes it would catch and sometimes it wouldnt

I was looking at that also I’m going to put it back together today and see what happens then if I’m not satisfied I’ll call inventables

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You say you generally do acrylic, which I’m guessing is a a pretty constant thickness, so in normal use are you just using a small part of the Z axis range ? Are the tight spots in a part of the movement that you generally don’t use ? If all your material is 1/8" to 1/4" thick, you might only use 1" of the z axis movement on a daily basis.

Your right all my acrylic is .220 so I rarely move beyond that spot when I ran all the way up and down it was fine 2 inches up but had a problem going back down

I actually chose not to use the delrin nut, but rather i purchased a 4 start acme lead screw and anti-backlash nut, then mounted the anti-backlash nut to an aluminum block… i lose about 15mm on z-axis travel, but then again, i don’t have to worry about some bit of plastic gumming up the works every few months.

Please send pics so I can see what your talking about

This could be an interesting upgrade o the delrin setup.

If the issue you’re talking about is outside your normal usage area of the Z axis, chances are you just need to wear the delrin nut in over the length of the acme screw. Run the Z axis up and down over the length of the full travel about 20 times and then report back. It might be that you have some other assembly problem, a search in the forums will help solve that is it is reasonable common.

Well I took it all apart and I’m will be putting it back together when I get home and see what that does to it.

lol. Well… I’m not going to tear down the Z-Axis to give you an exploded view, but here’s a picture of it on the machine… Basically what i’ve done is milled a solid aluminum block the same dimensions as the delrin nut, i then center drilled it to the size of the acme nut’s OD, and seated it, then i drilled and tapped two M3 holes to mount the nut to the block, then milled off the edges of the nut flange so they were flush with the faces of the block. After that, i marked, drilled, and tapped the holes on the aluminum block for the z-axis plate mounting.

Hope that helps explain things, if you want i can also create a schematic for you

Well how much would you be willing to sell one for?