need constructive critique

[Welder Kenny]

Hello friends,I need some help my hole cutting is not good any help would be greatly helpful

IMG_20220528_130643170.jpg (63.5 KiB) Viewed 1129 times

[djreiswig]

The holes don't look too bad to me.
Are you piercing towards the center of the hole? Maybe try an arc lead in. Also, circles usually cut better at slower speeds than you use for straight cutting. Try practicing on some scrap using slower and slower speeds until you get a good hole. I've seen anything from 80% to 40% speed depending on the material thickness.

[SegoMan DeSigns]

Are you allowing a pause at the end of a cut? on 1/4" and below I have that at 0 in sheetcam.

[adbuch]

I assume that the second photo is showing the backside of the part. It is possible that your divots are larger due to cutting the same location twice - once at pierce lead-in and once at end of cut. If your software permits, try adjusting your "gap at end of loop" to some small positive value to stop the torch at the end of the cut path before it reaches the original lead-in location. You may find that for the correct value, your divot will be much smaller and the center of the circle will still drop out on its own.
David

[adbuch]

You may also find this helpful.
David
https://www.hypertherm.com/en-US/learn/ ... th-plasma/

[ruralfencer]

I layer my drawings so I can run inside offset for circles and have lead in and lead out arcs.

[adbuch]

I layer my drawings so I can run inside offset for circles and have lead in and lead out arcs.

Are you using SheetCam?
Thanks,
David

[Welder Kenny]

yes I'm using sheetcam, I have a lead in .125 but not a lead out, I also put in a rule to slow down when cutting holes 1.250 and smaller.

[adbuch]

Kenny, does Sheetcam have the option to set Gap and end of Loop? As I mentioned above, this could possibly help. I have found that my best results are obtained when I have lead-in perpendicular to cut path (90 degrees), and set my gap at end of loop to a positive number. If you don't have that option, you could possibly draw your holes as incomplete circles to simulate the gap and end of loop. Other than that, it sounds like you are doing everything correctly to achieve nice cuts.
David

[djreiswig]

I think SheetCam allows a negative overcut. I'm not positive, but I know it's been brought up on the SheetCam forum.

[acourtjester]

I think in SheetCam you would use a cut rule for torch cutoff before the end of cutting.

[tnbndr]

For sure you need a lead out. Maybe a little larger than .125. Play around on some scrap.

[Welder Kenny]

Thanks everyone for the input I'm going to try some of those ideas, going to check the rule and I just changed my lead in and lead out.plus stop before end of cut. Thanks again

Kenny

[cstroke]

I'd double your lead in if not more. I'm running 1/2" lead in when I can, it helps stabilize the arc before the magic happens.

[adbuch]

I'd double your lead in if not more. I'm running 1/2" lead in when I can, it helps stabilize the arc before the magic happens.

[ruralfencer]

I layer my drawings so I can run inside offset for circles and have lead in and lead out arcs.

Are you using SheetCam?
Thanks,
David

Yes. I'm using inkscape for arty stuff, Qcad for editing and design, sheetcam and Mach3