Help a newbie out

I think i messed up… I was having issues with my table not cutting consistently. I notices some of the carriage bearings not touching the rails, i used the youtube video to level the gantry and the outside bearings still floated. I noticed the tops of the red bearing blocks not fully flush and took them loose and adjusted them until all the bearings made contact with the rails. The inside bearings had more preload, now they all have roughly the same.
I have tried every adjustment i could find on the forum but it still cuts off.
I cut 16ga and did not notice any ill cuts until today when i cut 1//4" and 3/16". The outside cuts and inside cuts have huge bevels and the holes are oval with blowouts at the bottom of the piece. I changed consumables, checked torch height, wiped down the rails, greased the lead screws, checked the lead screws for hangups, but still cant figure out the oval cuts and bevels.
I know the gantry assembly comes preassembled and adjusted on a fixture…did i mess up by loosening the bearing blocks other than whats recommended in the videos?

Thanks for any info.

If 16 ga still cuts fine, then you know it’s not a mechanical issue. If you don’t want to waste any more metal, try to mount a sharpie in the torch holder. Have it draw some circles and squares. If they look and measure correct, you know it’s not mechanical. If you get ovals instead of circles that usually an indication of backlash, check your lead screw set screws.

If you don’t find backlash, it sounds like you have a cut speed issue. Have you cut 1/4" and 3/16" before with success? Post your machine, amp settings, feed speeds etc, and if possible photos of the cut and the gcode. Hopefully someone will then be able to spot your problem.

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Greg thanks for the input.
More info:
OG CF, cut30i, 30a, 20ipm, 70psi at machine while firing, 3/16 plate, new consumables.
I did cut 16ga up to 3/8" with relatively no issues, but the holes have always been off, either beveled cuts or blown out at the bottom.
Doing art stuff, which was not my intent for the table only issues are the excess dross. Cutting parts thicker than 16ga is when i notice all the issues. Of course this is after my attempt to level and square everything.
I purchased the table used in Jan and transported it in the back of my truck assembled and always noticed the gantry not level and not all bearings contacting the rails so i attempted to readjust everything.

Here are pics of the cuts i noticed the issues after the “adjustments”.
The X is start X0/Y0

Checked for backlash on the lead screws and they were tight.Orbital Mount.tap (7.1 KB) Orbital%20Mount

Thanks for all the help!

Here are the two pieces 3/16" and 1/4"

And 18ga for a buddys kid

I don’t have enough experience cutting to give much advice on the cut quality. I’ll just note your machine is only rated to 1/4" for hand cutting. What are the size of the smaller holes? for 3/8" bolts? I think that’s a big ask for most machines. The larger holes in the thicker plates appear round on the top side, at least in the picture, kind of hard to tell. The 18 gauge one looks round. I think the good news is that it’s not a mechanical issue with the carriage. That doesn’t rule out a mechanical issue with the torch in relation to the cut piece. Since you can cut thin material successfully but are having problems with thicker, it could point to the torch not being perpendicular to the metal being cut. Check that the torch is square front and both sides.

Thanks again Greg, i’ll do some more checking/adjusting.
I was able to cleanly cut 3/8" before, but a lot has changed in the shop since then…

Made some test cuts today.
2" squares and 2" circles on 1/4" plate.
Using both shims.
The bigger shim seemed to make better cuts but still leaving a bevel.
Both squares and circles are , longer by 0.02" on one side. Did 6 cuts ranging from 25-35 ipm with new consumables.
Dross on the bottom side is still there, but I’ll worry about that after I fugue out the main issue.