Hi All. My name is Reg and I am a new member. I am still trying to figure out if my son was doing me a favour or putting a curse on me when he gave me this mpcnc Primo kit. From reading some of the posts I see I am really in for a challenge which is way above my pay grade. Anyway, I am taking things one step at a time and for now I will be content to just get the x and y rails as well as both gantries put together. I have not been able to find step by step instructions for dummies and hope someone can steer me in the right direction. So far I have the x and y rails assembled and I am about to start the gantries and z assembly but ran out of 1 inch tubing. I have made my x and y axis 24 inches but am at a loss how long to cut the tubing for the z axis. I would be grateful for any advice that may be forthcoming.
Welcome to forum.
There are parts of the build that can be tricky but worthwhile once it is up and running.
Which one are you assembling? You mentioned the MPCNC Primo but your topic is under the ZenXY section.
Here are the documents for the Primo: Introduction to The MPCNC - V1 Engineering Documentation
Here are the documents for the ZenXY: ZenXY v2 - V1 Engineering Documentation
I am going to make the assumption that you are making a Primo since you stated that and are talking about Z axis and the ZenXY doesnt have a Z axis. @vicious1 or @jeffeb3 can you move this to the MPCNC Section?
You came to the right place for help! Post pics and ask any questions you have and we will help you along the way! Lots and Lots of experienced builders here on this forum who are all willing to help as much as they can!
There’s a section in the documents called the Calculator. It will give you tubing lengths once you’ve entered your desired work envelope.
Yes, I recall seeing something about the calculator and yes it is the Primo I am building. At this point I have the x and y rails as well as the gantries installed (I got more tubing today). I now have to wait for my son to print a few parts that broke due to overtightening, I am learning that this plastic can’t take a lot of pressure. I expect that with 24 by 24 base I should wind up with a usable workspace of about 18 inches square but I guess its probably best to wait until the router is mounted to determine exactly what the workspace will be. Would I be correct in assuming I will have to determine the maximum drop of my subfloor before referring to the calculator for the length of the two z tubes? I am trying not to take on too much at a time since this project is a bit daunting to me to say the least. If I just do it in baby steps without looking too far ahead I might not get so depressed LOL. Its great that there are so many people on the forum who have all that experience building these things
Just remember that people come here when they have trouble, or they want to stretch past the “normal” operation (what we call the yellow brick road). So I expect your experience to be simpler than most forum posts.
Overtightening is a common issue. The design is to use parts and screws big enough to be common and strong enough. But they are more than capable of destroying the parts if they are tightened to their capacity.
I have reached the point in my MPCNC Primo where the x and y rails are installed and square and I am working on the z-axes. All the parts which are made to accommodate the 1’ rails seem to fit perfectly, nice and snug but not over tight, with one exception. The holes in the z-coupler and z-motor seem to be about 1/32 in too small. This kit was printed by a fellow who has since passed away and my son acquired it from his widow about two years ago then passed it on to me. I am wondering if the guy who printed the kit perhaps printed the wrong size z-coupler and z-motor parts. Just thought I would ask before I bother my son to print new parts.
From the Docs:
There are 3 different sets of printed parts C-23.5mm, F-25mm, or J-25.4mm (1 inch). The measurement is for the Outside Diameter of the conduit/rails/tubing.
The parts that contact the tubing should have the letter C, J, or F embossed in them somewhere to show the size of tubing they’re designed for.
Thanks for that info Tom, as it turns out the two parts with the undersized holes do in fact each have an “F” on them (really hard to see too, I had to use a pencil and overlay a piece of paper to see if it was in fact a letter. So that explains why the holes are too small. I’ll ask my son to print the new parts. Thanks again. Reg
Glad the information helped!
Great catch.