Lowrider CNC Track Wheels Mod

grabcad

I was having a problem with my 1/2" MDF y-plate and wheels bowing inward, causing some wobbliness in cuts on the y-axis. I made a couple of modifications that seem to have fixed the issue for me:This first fix is probably enough to help most people. I added metal braces between the wheel bolts on the inside of the y-plates to keep the wheel bolts straight. According to the DXF file for the y-plate, the wheel bolt hole centers are 308.2 mm apart. So I drilled two holes 308.2 mm apart using a 5/16" drill bit in a spare piece of thin angled steel I had lying around my garage. I added a couple of washers to the wheel bolts before this piece to keep the wheels from rubbing against them.(Note: I would recommend using something like a flat aluminum bar instead of an angled piece, because the angle interferes with the gantry on the x-axis, causing me to lose a bit of cutting area near the edge.)This next step is probably overkill, but it was a fairly cheap mod so I went for it. I'm sure you can see from my photos that I've replaced the original skate wheels with these wheels that I designed to ride in 1/2" aluminum u-channel. (I used the same bearings from the skate wheels.) I bought two - 8' pieces from my local hardware store for $40. I used clamps to hold the channels accurately in place while attaching them to the wasteboard with screws and took my time to get them as parallel as possible. (This is crucial to keep the wheels from binding)