I’ve just completed a Lowrider 2 build with a cutting area a couple inches longer than 48x96. I’ve run a bunch of small tests and things are mostly running well. Today, I need to make some longer cuts, full 96" and I started running the gantry out to the end of my Y axis and then bringing it back to 0 without any cutting. Unfortunately, the bit ends up about 1/4" left (-X) of where I started. It seems to track out fairly straight (+Y direction) but wanders left when it is coming back to the origin (-Y). I’ve tightened all my belts. I’ve squared the machine. I’m using the double end stop so it auto squares at the beginning and it starts out square. Both motors seem to be working, I’m not hearing anything skipping steps. I’m using the endstop/belt holder on thingiverse by Tailside and have used those to set the width of the table so the Z tubes are sitting equidistant from the rails.
I’ve run out of ideas to troubleshoot. The wheels are just rolling along on MDF and it is getting off track enough that the wheels are nearly falling off one side. Any ideas?
I’m about get desperate and try some y-rollers like those on thingiverse by GoatDIY (won’t let me post links). Might print those overnight if no one else has any ideas. Thanks!
Pulleys was my first thought too. Also check that your y plates are actually parallel to each other. Or maybe move the y plates in closer so that the z rails are even closer to mdf, using the edge itself to keep you tracking straight.
…I got tired of trying to tune this out and just put down some 3/4" aluminum angle to guide the skate wheels.
Thanks for the advice. Pulleys and grub screws are all good. I guess I’ll try some sort of guide. Either some y-rollers that mount on the plate and roll along the edge of the table, or a wheel guide. For those of you who did a wheel guide, are you basically laying down a 3/4" strip or whatever on each side of the wheels so they just roll down a narrow channel?
Did you check your belt tension with the carriage centered on your workspace? It smells like you’ve got slack on one outfeed belt, so everything is square going one way, but not the other. Alternately, double-check for debris or damage to your wheel paths.
That’s what I thought too. I had that problem on the X and tightening the belt a couple of clips on the zip tie fixed my x axis but that hasn’t solved my Y problem. I’ve checked for debris and damage and everything is nice and smooth and flat and should be running fine.
I’ve got two options for paths forward and trying to decide between the two. 1) print a y-axis roller that mounts perpendicular to the wheels and rolls along the edge of the table. or 2) cut some strips of 3/4 plywood and place them on the inside of the wheels to keep them from turning as there isn’t much room on the outside.
I’ll have to redesign a part for 1) so am going to take a look at that and then print it overnight and/or cut the strips in the morning and try this again.
Just wanted to let everyone know that I installed a rail just on the inside of each of the wheels and it seems to track smoothly and straight now! Thanks for the suggestion! Now to make some sawdust! 4 hours of cutting t-track slots in MDF for my new workbench top… Really wish I had time to come up with a dust solution before I started this but I need to get it made! Thanks again everyone for the helpful and rapid help!