I’ve been noticing a lot of slop in the plastic part that rides on the Z-axis screw—looks like it’s wearing down, and the screw itself has some wear too. I’m looking to 3D print a replacement using a stronger material like carbon fiber, but I’m having a bit of trouble dialing in the screw dimensions. It seems like the wear is mostly in the middle of the screw, since the part fits snugly at the top and bottom but gets loose in the center.
If anyone knows the exact specs for the lead screw or where Langmuir sources them, that would be super helpful. I’m guessing it’s either a 3/8-8 ACME thread or a TR10x3 trapezoidal thread. A direct link to where they get them would be even better.
I was hoping one of them would chime in tonight so i could get one printed with the right profile. I was going to call tomorrow if i hadnt heard anything. Ive got a whole second z axis but they are both sloppy from everyday use. Id say i get about a year of use before the z nut gets real noticeable slop in it.
Ill end up ordering new ones tomorrow. This is just to get me back up and running till it arrives. The set i have on the plasma now is jamming. I have my buddy the spare set i have to work with
One thing I have to mention, that I have experienced since the start of CNC, and have experienced it on my Crossfire XL, as well as my Crossfire Pro, and on my replacement Z axis assembly.
It will sometimes “bind” up and activate IHS as it jogs down sometimes to initiate height sensing.
I had contacted Langmuir as I suspected it was the black plastic nut you’re looking to make yourself. Well, I got an entirely new Z axis assembly and it did the same thing from the start. I was even able to demonstrate it with the assembly off the table, and spinning the leadscrew by hand.
Happened on both a new unit as well as a used one. Just something weird about the last two inches of travel or so (even with enough of a gap to prevent from bottoming out).
Yup, ive experienced that as well and it is likely due to the odd screw size paired with the acme threads on the screw. Ive broken countless(12) of the other half of the ihs sensor from it not sensing correctly. I have started printing those in bulk and have beefed up the design which helps. The problem with plastic parts is they become wear items.
The odd part though, is the new one would bind up exactly the same before it was ever installed. Just turning the leadscrew by hand would cause the IHS to catch a good inch or two before the coupler got close to bottoming out.
the problem im finding is that early on they used a 1 start screw, and then later switched to a 2 start screw. i have a new screw and nut coming in the mail and will see what style they are using now. and from there i will work more on figuring the screw out. i spoke to them on the phone and they are not able to disclose the thread information on them, i can however confirm it is acme since that is in the part number.
