Hello guys, I hope you’re all fine.
I’m in the assembling process of the MPCNC and I have two problems now
1- Is the T8 Anti Nut Reaction important ? Because I don’t have it
like this
2- After assembling the Z axis the lead screw was so long, should I cut it or buy another one smaller?
I cut mine and have enough for 2 z holders now. It only has to be long enough to hold till the first set of bearings drop off the tube correct?
Actually I’m not sure but it seems right depending on the explained videos on YouTube.
How to measure the length of the leadscrew?
My cnc working area is 500-X 500-Y 80-Z mm
Those anti backlash nuts will just cause you pain. The router will hold it down enough that there will be no backlash.
Since you already have it assembled it’s easier to cut to length based on the assembled Z axis.
The leadscrew must be short enough that it does not extend beyond the bottom end of the Z tubes.
The leadscrew must be long enough that when the Z axis is fully raised (bottom bearings at the end of the Z tubes) the leadscrew must still engage the leadscrew nut.
There is quite a bit of range between these two lengths. Any length in this range is ok. My personal preference is for it to be just a little bit shorter than the bottom of the tubes.
The screws come with one. You can get extras if they wear out. I don’t thunk there is anything particularly special about them, but it does have to match.
I’m actually thinking of cutting mine shorter so that the tubes are on the lower bearings when the Z engages. My reason for this is that unscrewing all that leadscrew every time I remove the Z axis is a pain.
That’s why i asked because i lost them sadly and i went looking for them locally but i didn’t find anything. Is there any other way to fix this?
Thank you
Well, you need at least 1. They are commodity parts. You should have a T8 leadscrew with a 2mm pitch. Most of us use a 4 start, which I think is called a T8-8. But some have found a one start T8-2. You can look at the end of the screw and count the starts to know which one you have, and then hit your favorite online store (amazon, or whatever) and find one. They are quite common for 3D printers and they do wear out faster than the screws, so they are a common spare part.
That’s what I thought. Thank you so much, you’re a blessing
