I could pay someone for showing me how to use a plasma cutter (Chicagoland)

As some of you may remember, I remade my old Hobart CyberTig to be controlled by a microcontroller and it is now capable of doing "high
voltage DC" of up to 300 VDC (as well as low voltage high current DC of up to 80 V).
The use of low voltage power supply is stick and TIG, which already works.
My intended use for high voltage power supply is to make a plasma cutter. I have a compressor and air dryer. My problem is that unlike stick and TIG welding, I have never done any plasma cutting, have no friends who do such, and would like to see how it works. (I have read some stuff, but reading is not a substitute for experience)
So, if anyone of you are in Chicagoland, own a plasma cutter and would like to get paid some sensible amount for showing how one works (beer is on me), let me know. thanks
ichudov AT algebra DOT com
i
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On Fri, 07 Jul 2006 14:39:59 GMT, Ignoramus12948

Does technicalvideorental.com have anything on the topic, I wonder? That guy ranting about them the other day reminded me of 'em again. Worth checking out anyway.

Igor buys good beer, for the record.
Dave Hinz
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That's a good idea, actually, thank you.
i
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On Fri, 07 Jul 2006 15:31:35 GMT, Ignoramus12948

Once in a while I have those ;)
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Before you go thinking it's something complicated, try this: connect the unit (plug in the power source, plug in a source of clean dry air at the right pressure), then connect the ground lead to a distant corner of the work, put on some #5 shades, hold the torch 1/16" or so above an edge, otherwise straight up, pull the trigger, and move away from the edge, and see what happens. It's a whole lot like an oxyfuel cutting torch except electric, also the slag seems easier to chip off.
GWE
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You know Grant, I think that yes, I should try just that. I can try a "scratch start" without HF, I think, right? (I just care to get an arc going and cut something somewhere) I do not think that 300V would get the arc going from 1/16 of an inch, maybe I am wrong.
Is the torch going to be positive and work lead negative?
i
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Miller Electric has a whole online library of articles: http://www.millerwelds.com/education/articles/articles17.html plus you can download the instruction/owner's manual for their plasma cutters for info & ideas: http://www.millerwelds.com/service/ownersmanuals.php For whatever that's worth, David


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David, thanks, I went and looked and even found a few plasma cutting videos. I am downloading the plugin and will soon view the videos.
i

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On Fri, 07 Jul 2006 19:57:30 GMT, Ignoramus12948

Isn't the internet a wonderful thing? I mean really? Heck, I hear you can even get help with math homework at some places.
Things tend to come around, don't they?
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The torch is negative - a source of electrons - the source is often Hf. Plasma machines use a kick start coil - to arc and get the current flowing. Martin
Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH & Endowment Member NRA Second Amendment Task Force Charter Founder IHMSA and NRA Metallic Silhouette maker & member http://lufkinced.com /
Ignoramus12948 wrote:

-
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Interesting - guess that's a 'new' thing?
10 years ago i had a plasma - you definately had to touch the workpiece with the tip the whole time you were cutting. Tip was brass and needed cleaning a lot and changing occasionally - it featured a large central hole and 5 smaller ones around it.
Seems to me though - no matter if they touch it or not they do cut nice and quickly:)
Scott
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And to a chip code designer - look at Hypertherm docs for theory - they have a multi-step voltage/current that gets the current flowing and then dumps the beam on the work.
Martin
Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH & Endowment Member NRA Second Amendment Task Force Charter Founder IHMSA and NRA Metallic Silhouette maker & member http://lufkinced.com /
Grant Erwin wrote:

-
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Igor,
Feel like a trip to the shop in Joliet?
Rob
Fraser Competition Engines Chicago, IL
wrote:

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Sure! Absolutely!
i

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Cool- Drop me an E-mail off line and let me know what works best for your schedule. If you want to take the train in the Heritage Corridor and Rock Island hit Joliet. Funny thing is I just used it for about an hour this morning. It's been collecting dust for a few months and I really gave it a workout on some tubes from a wrecked chassis totally by chance.
Have a good one!
Rob
Fraser Competition Engines Chicago, IL.
wrote:

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Ron, I sent you email to your address on the next line, without NOSPAM. Thanks.
i

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