No, just the first cut / ie the first pass went slightly angled. The rest of it is fine and I did remember to put the tabs on this time… Here are a couple of more photos I did not realise I took.
So one shot shows the other side of the cutout/hole and it is fine. The other is the wonky bit.
Is the shift parallel to your belts? If so your wheels got nudged on the table. Before you start a job run the machine the full length of the belts a couple of times to make sure they are tracking correctly.
So today did another run and it went funny again. I also was trying a 32mm 3.18mm bit that I bought and I was not happy with that but I don’t think that was the problem. It did not cut good circles.
It dragged itself across the table by about 3mm. Nearly failed the job at the end but I was watching and stopped it all.
So pulled the old girl apart.
Couple of observations.
grub screw on X axis seemed tight. But took it apart, cleaned it all with thinners and put it back together with locktite.
noticed that the teeth of the cog wheel thing look like they have been deformed a little bit. See photo. But I don’t think it is the problem. (sawdust?)
3.slid the carriage back and forward with out the belt off and it runs really freely across the X axis, not binding.
considered my patent brush dust shoe could be catching and dragging the setup to one side but I doubt that. So have removed and am printing the one with the shower curtain as a barrier. Should be done in 10 hours.
noticed on reassembly that the X axis Stepper seems sort of loose in it’s frame on the plate. See video…
Does this look right or should I take it off and disassemble it too and retighten everything…? Or does this settle when the belt is on…? https://photos.app.goo.gl/xLjGcPGF8Yiy1Y1V6
The pulley looks fine. It doesn’t have to have a perfect finish to be accurate. Most of the surface is good. The motor being loose looks like maybe the screws going into the motor are loose?
Are you sure your wheels aren’t just skipping sideways?
When a motor skips, it sounds a little like gears crunching. That is going to happen if things go wrong. Nothing mechanical is grinding though, it is just the motor jumping from one phase to another really fast.
I don’t think there is enough ‘slack’ in the gantry to allow it to move across the table but I have not checked that.
Will reassemble and look for that effect. Guess the idea is to go then put some L bracket on the sides of the table to hold the wheels? I remember seeing photos of something along those lines on the forum.
I have found a couple of things but your last comment is the one about the thing drifting +/- on X axis. ie wheels move left and right
redid grubscrews.
that wobble in the stepper was due to a bolt missing??? Fallen out or failed to put in.
went into town and bought more.
refitted
got a bit of aluminium L bracket and there is a 5mm drift across the x axis for the whole gantry. ie I can push/pull it 5mm either way.
6.did a test pattern in Fusion and it cut fine but you could see it pulling the wheels one way then the next.
So… going forward.
do I tighten up the gantry across the x axis to take that 5mm out and create friction in the setup
or
do I go and buy 2 lengths of L bracket and screw it to the table to stop the wheels drifting left and right?
Hi, New to the forum. There is a thingiverse part that uses rollerbearing wheels on the side of the table which are perpendicular to the Y axis wheels. This seems to help keep the X axis from drifting. Have only used a couple of times though
I don’t know of one on TV but I did one for my rolling-gantry FoamRipper… which runs on a hollow-core door. There’s one on each end of the gantry and opposes whichever way your gantry wants to drift. It’s obviously unique to my machine but its the same concept and could easily be adapted for another machine…
Depending on the table I suspect you could shim the unistrut to suit.
I spent the better part of a week dialing in my table by sheering off tiny bits of the sides until the table was trued up. The effort was worth it in the end I suppose, however I could have saved substantial time by just using the conventional/tested solution.