Cut quality on smaller openings

[Spb311]

Hello, I am having a problem on cutting smaller openings say 1/4"-1/2" wide. The cut gets jagged and there is a tab where it lead in and lead out. I have a Thermal dynamics A120. I tried cutting something out of 1/8" steel with 40 amp settings. The larger cutouts came out ok but the smaller ones look horrible. I am new to cutting detailed items. Can anyone recommend anything to try? Am I asking for too much?

Thanks

[tnbndr]

Here is a file I saved that Jim Colt posted a while ago.
There used to be some stickys in one of the forums with his tips and tricks but I don't see them now.

[Brand X]

No real way to really help, with limited info. Table type,parameters including the table ones.. Maybe run some exposed 20 or 30 amp tips on the cutmaster a-120.. cut height .1400 air pressure 75 psi You can put the machine @30 amps on the dial, and get good life even out of the 20 amp 9-8205 tips..(same orifice size as the 9-8206-30 amp tip) I would get awesome cuts out of the A-120 I had. It will also go lower on the dial, and seems to be way under the 30 amp low end advertised.. The cutmaster series loves good factory electrodes, or all sorts of problems show up..You would think a tip or shield is messed up, but a new electrode will do wonders without changing any other part..Aftermarket electrodes/tips are a no-go too..

I am one of the few around that really think the cutmaster is a excellent machine.. They are not the easiest machine to figure out, but once you get on to what they are telling you, they work great.. I am kind of thinking use the A-120 air parameters/Kerf settings, and the Cutmaster 52 machine cutting parameters for everything 60 amps, and below.. I also believe the 50/55 amp tips(80 psi) are another underused option.(like the 70 amp tips) Yes,Victor/Thermal calls them tips. 40 amp tips can work better by lowering the amps to 35 in certain cases. Try that first..They are some of the trickiest tips to use on the cutmaster..(IMO) Try exposed, and shielded too..

Pictures help too..

Like my favorite ones lately..

[Brand X]

I tried the un-shielded .9-8206 (30 amp) tip on .120 ms.. nice cut but too much dross.. I needed to work up a .120 MS setting anyway..

40 amp tip (9-8208) Shielded.. use 40/35 amps and see what you prefer.. Pierce height .1900/ Cut height .1400/ Arc volts 112/ 80 ipm.. works for me, and excellent cuts.. Play around with the IPM of course.. This is a cutmaster 52, but I don't see much difference between the A-120, 60 amps and below..

[Johnnybravo]

I had a similar problem with my table. Turned out that the drive belts on my Xbox and you axis were a little loose giving me some backlash.
Don't know if that helps...

[Spb311]

Johnnybravo,
How much play did you find? I did find them to be a little loose but nothing extreme. I am tightening them up and going to try what others have said. Can anyone tell me what effect having the air pressure too high would cause?

Thanks