Cut Bevel Problem Hypertherm Powermax 45 & Plasmacam DHC

[knoeberm]

I'm running out of ideas as to why I'm getting beveled cuts! It's happening on all types of steel, too.
I've got a Powermax 45 on a Plasmacam DHC table. My torch is a manual torch, not a machine torch.
I've got a couple of jobs using 10 ga steel, and I'm getting a positive bevel.

My settings are close to the recommended settings in the book:
Cut speed : 145 IPM
Cut height: .063"
Pierce Height: 0.15"
Arc Voltage Shift: 1
I've got the air running through a water trap/regulator right off the compressor, then another filter right behind the cutter made by Thermadyne that claims sub-micron filtering.
I've had bad luck letting the machine set pierce height, so I've been manually setting it before each pierce.

I check the cut height periodically, and it seems to be maintaining it well. A positive bevel should mean I am cutting too high, right? is it possible that the shield on this torch is "hiding" some of the cut height? If so, is there any remedy for that? I'm afraid if I get much closer, the height control won't be able to keep up with warping on thinner stuff, and will cause the tip to contact.
Any ideas?
If I wasn't already bald, this cut bevel thing would send me down that road!

[jimcolt]

You don't say how much of a bevel you are getting.....there will always be a bit of bevel, and it should be consistent all the way around the part. Your comment about the shield.......you should be using the machine torch shield, and yes, it will work on your hand torch. The hand shield is designed for hand cutting while dragging the torch......the machine shield is shorter and is designed for use with a torch height control that maintains the .062 standoff. If you are holding .062 from the face of the hand shield, the torch is way too high, which will increase the bevel.

Get the right shield.....try that....and if the bevel is still unacceptable for you.....turn the power down and slow the cut speed down.....you will have to experiment to create a balancing act between edge squareness and dross. The 45 will provide cleaner squarer edges that any other air plasma I have ever tried or seen.....but it is not a high definition class plasma (10x more expensive!) or a laser (40x more expensive!).

Let me know if the different shield helps...

Also....PlasmaCam has an upgrade for your DHC machine that brings it up to the DHC2 specs.......according to everyone I have talked with...it is worth every penny as it gives superior initial height sensing capability before every cut....this insure accurate pierce height and accurate cut height without intervention....and improves consumable life dramatically.


Best regards, Jim Colt

[pipeliner]

Hello, new here, very nice & helpful site, I have DHC2 w/Hypertherm 600, Jim is 100% correct ,with the hand cut sheild, the standoff has you .062 off the plate to start, you need a machine sheild, I am using the hand torch like you, I'll check the Voltage shift today, they all vary in settings, tell you where I'm at, this will correct any digital highth control problems. 10 gauge I run 85 IPM, 40 Amps, .110" peirce, .062" cut, with a nice & very little easy to remove if any slag. Hope this helps you & will post Voltage settings tonight when I get home from work.

[knoeberm]

Thanks for the help guys. I've got the new shield on the way - nearest dealer is 35-40 miles off.
I'm getting about 10-15 degrees positive bevel (as close as I can estimate). I've seen the DHC2 tables in action, and they've fixed everything that frustrates me right now. Unfortunately, an upgrade doesn't look like it's in the cards - I'm running this table in a high school setting, and budgets are too tight to allow it.

[jimcolt]

It wouldn't hurt to call PlasmaCam sales and describe that you are an eductational institution.....and that everyone has told you the DHC2 upgrade will help your students understand the process better...it may help!

Jim