Circle and Slot quality

[corncrazy]

would any one here be willing to post up some pictures of your small slots and bolt holes for me to compare my results against?

[jimcolt]

These are cut with a Hypertherm Powermax85 on 1/4" steel at 45 amps. Bolts fit through very nicely.

Jim Colt

would any one here be willing to post up some pictures of your small slots and bolt holes for me to compare my results against?

[corncrazy]

what machine did you cut that on and what tip and speeds

[jimcolt]

The pictured parts were cut with a Hypertherm Powermax85 using the 45 amp shielded consumables at 45 amps. Cut speeds for the outside perimeter were at book settings (dirctly from the Hypertherm operators manual) the holes were cut at approximately 60% of the book settings. The cutting machine was a PlasmaCam DHC2 with full height control.

The book speed for .25 steel is 48 ipm.


Jim Colt

what machine did you cut that on and what tip and speeds

[dynatorch85p]

i use lead ins in my circles and slots i will try to get a pic tomorrow for ya but i use the same plasma cutter as you but a dynatorch table with thc. When i do a circle or slot i use the lead ins that the shape program has that came with our table and it starts at center and goes out at a .25 radius.I always get a lil spot there where the lead in came out and started to go around or sometimes i get ovaled holes to. But the finecut will usually make beautiful holes like u have there but no matter what we gotta make our holes a 32 or 1/16 bigger than what we want so it comes out right did u do that there i tried all kinds of feed rates and pierce heights and torch height but usually keep the powermax at 85 or 80 amps unless i and using fine cut tip.the boss only buys 85 amp shielded consumables and 45 amp fine cut I run this thing at work so cant scrap to many things trying to many different things but u think turning the amps down will help me or not. I also i seen somewhere that u work for hypotherm our powermax is like 9 months old but i notice alot of times the thing will sound like air is blowing straight through it if i lower the torch down u can see if bubble in the water and this is long after its done cutting and the only way to make it stop is by unplugging the air for one sec then plugging it back in then its good to go but it does this pretty frequently.it aint done it in the last couple days but i am sure it will. The only air filter we got is the one that came on it would dirty air cause this. What about to much air we got 2 compressors but idk how much air we actually got back that far its a pretty big shop and we got one compressor like 25 ft away and one like 40 ft away but is only piped with real small pvc and some regular size aire hose.But the gauges both read 100 pounds so thats 200 but the filter bowl is only supposed to have 135 and it aint blown. it has before when some idiot plugged in a commercial compressor in and the bowl got a bunch of little splinters in it had to get a new one. We also get the 0-30 error code more than usual i think also sry this prob isnt the right forum for all this but this one came up in my search thank you i will take some pics for ya tomorrow

[pertneer]

The air blowing after the cut is important as it cools the torch down after the cut. By you stopping the air you may be prematurely damaging the consumables. I could be wrong that they are damaging the consumables, but it may be. The 0-30 error code may be an indication of the air being shut off prematurely.

Dirty air or air that is not dry will cause issues. Having the two air compressors plumbed together (I assume because you added the pressures together) does not double the pressure. It is still 100 PSI total assuming they are plumbed together.

If you have to add to the size of the hole I wonder if the machine is not calibrated correctly. Are any of the straight sections also incorrectly sized after the cut?

[dynatorch85p]

I know what your talking about with the air blowing through after a cut is done i dont stop that i always let that finish it only takes about 10 seconds. But what i am talking about is a little different and it will do it all day if i dont unplug the air for a sec. I have come into work in the morning and it was doing it i thought the cup cracked again cuz someone must of left the compressures on overnight but it wasnt the cup it was just blowing through and it blows clear to the shield but there aint much air coming out at the shield but the air going through the plasma sounds like alot. I am pretty sure its just dirty air causing this though. I will get some pics up of the holes here soon so we can try to figure those out thanks