Jim: Optimizing Small Hole Quality (Edge Control) - Pics

[racesol]

These flanges were cut with the HD3070/HYPR torch ugprade. 85 IPM. 3/8" Plate, MS. The cut quality is superb. Minimal dross. Square edges.

However, the hole quality has something to be desired.

What can we do to minimize the apparent ovalization of the holes? Is it possible to slow down the control when it cuts the holes and have it cut the rest of the flange at full speed? We have experimented with changing the arc radius from .09 to .11, but since the holes are 0.403" we can't get much larger.

Thoughts? Thanks!

BTW: Jim & Bob at Hypertherm Tech Support deserve a serious pat on the back for the level of knowledge and experience they have provided to me in getting this system running. I couldn't have gotten all these bugs ironed out without them! Having talked to tech support nearly everyday for the past week or two, I have to say hypertherm has one of the best tech supports out there bar none. I wish we had this level of support in the bending machine industry!!

[jimcolt]

If you send me a direct email I'll be happy to send you a .pdf copy of a pesentation called "best practices for hole cutting".

Here are the critical functions to hole cutting:

1. Torch pierce height
2. Torch pierce delay
3. Torch physical cut height
4. Ability of the machine code to freeze height at the physical cut height (for holes only)
5. Location of pierce hole (dead center of hole)
6. Shape of lead in (depends on the mechanical and acceleration ability of your machine)
7. Ability to program an overburn instead of a leadout.
8. Ability to shut the plasma off in advance of stopping machine motion.

The presentation will get into more detail!

Jim Colt jim.colt@hypertherm.com

[racesol]

Jim,
I sent you an email for that presentation. Thanks
Adam

[jimcolt]

Adam.....I don't have an email from you. Need your email address if you want the hole cutting presentation.

Jim Colt

[racesol]

Jim,
admin@mandrel-bends.com

Also an add behavior with the PHC I'd like your input on. We issue an F30 for speed then an M50 for torch height freeze. 50-60% of the time, the holes are cut @ 30ipm and the torch head comes down touches off to preset distance, hold light goes on the phc and it cuts without issue. The other 40% of the time it starts to cut and then retracts about 1/2"-1" an inch. Any insight?

[jimcolt]

That certainly is not supposed to happen! Sounds like possibly electrical noise......do you have everything well grounded and a ground rod driven?

Jim

[racesol]

We poured a 30' ufer ground 5 feet from the machine. Grounding is good. I think we were setting the pierce height to high and a loose electrode. The combo was getting us arc failures.

Please resend that presentation at your earliest convenience. I didn't get it if you sent it this time around

Adam