I’m putting my LR2 together and I noticed that the X rails are forming a trapezoid with the XZ Main. I have tried everything I can think of to get the 2 X rails to square up to the XZ Main but I am stumped. The “left” side of my LR2 has a gap on the “back” rail and the "right side has a gap on the “front” rail. The spacing of these gaps on each side is almost identical. Since pictures are worth a thousand words, here they are.
For troubleshooting, I have loosed up all the screws holding the XZ Main to the XZ and XZ Side Belt so everything is just holding together but I can easily manipulate it. Even with everything loose, I cannot get the gap out. The J Spacers are properly inserted in all 4 pieces (I just double checked that). I have also removed the Y Plates (and everything attached to them) from both sides. I haven’t yet put it on my table to check it (partly because I wanted to “dry” fit everything first but mainly because the table isn’t complete yet, lol). I have the X Plate installed and that is sliding ok with no binding. It doesn’t move as easily as I thought it would, I can easily move it with one finger but it doesn’t “coast” at all. Once I stop pushing it, it stops. It moves, but with some resistance. I don’t know if this is normal or not but I figured I’d let you all know in case there is something wrong with it.
I should also mention, that the flat parts were not CNC cut. I printed out the templates to scale and then spray glued the template to my MDF and cut out the parts with a Jig Saw and used my cheapy Harbor Fright Bench Press to drill out the screw holes. Everything seemed to go ok but I can’t be 100% sure. One of my first projects when I get this thing running will be to route out new flat parts.
Sorry this is a bit long but I figured more info is better then not enough - and I’m guessing I still forgot to add something.
Thanks Ryan, I was wondering if it might be the 3D prints themselves. I just loosened things up even more and with a little bit of pressure I can take the twist out. Do you think that will be ok in the short term? At least until I use this machine to print out the parts for my own MP3DP. lol. A friend of mine printed out all these parts for me…
Not the gap, the actual part. Your stepper does not even fit and there should be room I have a feeling it is way off. Put the calipers on right where I indicated on your picture.
Ok, so, I’m getting about 47.7mm. It looks strange though, three sides measure +/- 10% of 47.7mm and the 4th side (the Right Front - with the bigger gap) is measuring 46.75mm. Something is off in my friends printer it seems like. I’m guessing this is where any print issues would show up because of the 4’ width of the X axis that I am doing. Do you think shimming the parts to get them square would be ok or should I have him reprint after he recalibrates his printer?
I’m guessing the printer being out of alignment is why my stepper has no gap to the XZ Main “inside cross grid”? Looking at that, it does look like that part of the XZ Main plate is being bowed out slightly by the stepper…
Thanks for all the input and help Ryan!! These forums are a big part of the reason I decided to build one of these. All the support here from the community and from you is amazing!!
I guess the only way to see what happens is to finish it and see what happens with the Crown test. I should be able to get to that this weekend and I will post up my results.
I had my buddy who printed the part# for me check his printer and it was off by 5 degrees on the Z axis. It looks like you were right! Thanks again for finding that error!
Tell me about it! After hearing that I took a closer look at the printed parts and I can see a cant to some of them, especially the ones attached to the router plate that hold it to the stainless steel x-rails. They are noticeabley leaning to one side.
I might have to scavenge the hardware off my LR2 and have you ship me the printed parts for a MP3DP so I can then reprint them to fix the LR2. It’s the cycle of life. Lol.
Lol - it’s kinda addictive! I already have plans to build another LR2 dedicated to plasma. I figured I’d use the router to get my feet wet so to speak and learn the ins and outs of CNC before I add 3000 degrees to the party!
I also have a couple friends who are looking into the LR2 or the MPCNC.
