Another plasma component...

Fantastic info. Thank you.

rodw wrote: jimcolt

One of the overlooked components in a THC is the mechanical tightness as well as the lack of "overshoot" of the z axis lifter. A loose lifter requires that the voltage range (deadband) is loosened up, a lifter that does not instantly stop (braking) will do the same. The z axis lifter, properly designed will be the most costly part of any THC.

That's an interesting bit of info for me to keep in mind as I build. lol, I got about $50 in my z axis lifter!

AgentWD40 wrote: Fantastic info. Thank you.

That's an interesting bit of info for me to keep in mind as I build. lol, I got about $50 in my z axis lifter!

You remind me of Tommy. Hes the expert of ghetto builds!
Well it took me 3 months to build mine.
I figured If I could make that, I could make everything else!
If I did it again I'd buy a prebuilt stage and a breakaway.

That's an interesting bit of info for me to keep in mind as I build. lol, I got about $50 in my z axis lifter!

I have about AUD80 in mine plus some time and scrap bin parts for the breakaway and float switch.

Cheers, Phill.

AgentWD40 wrote: I certainly wouldn't argue with checking its calibration. I checked my thcad-10 with a 9.5v wall wart and a voltage divider circuit with a potentiometer. I checked it at several different voltages over the 10v range. The calculated voltage using Mesa's calibration frequencies matched my multimeter within 0.1 volts. Speaking just from my gut I think I trust mesa's calibration better than my multimeter. it's a cheapo meter, so I suppose that's the best I can do.

[edit]
Maybe another calculator for the user to plug in a series of their own frequency vs known voltage pairs and do a simple linear regression? let the user decide what they trust. I'm just thinking about convenience for the user. I would offer to do it but I know squat about gui programming in linux... maybe it's a good time to learn though

[edit x2]
Here's my test data. It was closer to +-0.03 volts, not 0.1v.
image missing https://i.imgur.com/JLdmA0I.png

Oh crap, I completely forgot to write down the calibration numbers on the back of my board before I installed it. I would bet my voltages are a good bit off. What I did was subtract the voltage it displayed when at zero volts (this was jumping all over +-20v). Then adjusted the other number till it showed what my volt meter showed. looks like its time to dig into the controller and get a peak at that label.

Well, from the discussion before it may not be necessary or worth the trouble. Your method may even work better depending on how much you trust your meter. Hows the quality of your cuts using mfr cut chart voltages?

Its a cheep meter so i'm not sure how much i trust it. Im running a hypertherm 30xp so I dont have a cut chart. I have looked at the 45xp chart and thy say around 111v. I have played with all kinds of voltages and in my line of work im after square edges and minimum HAZ. im going to switch over to fine cut consumables today with ohmic sensing off the nozzle and try that. I would like to completely remove slag but i would rather have the big slow cut slag that is easy to remove then the tiny slag that has to be sanded off. I cant sand or grind the surfaces of the blades i cut out so easy to remove slag is key.