So now that I have the 65 sync I was thinking I should start using Nominal Voltage?
What do you other Hyperthem guys think?
If I do go nominal how do i confirm cut height?
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I am contemplating the exact same thing. With smart voltage firecontrol has a selectable delay wired into it so the thc doesnât lock on to a false voltage that happens during the initial pierce and stabilizing time. As far as I have been able to glean, there is no such delay available for nominal voltage. The result will be the torch height fluctuating up and down untill the arc has stabilized, about 1/2" into the start of the cut after which the cut height will be held steady.
On large cut outs this may not be significant, but on small detailed artwork, 1/2" of âraggedâ cutting might be. Of course with fine detailed cuts the thc will probably be off anyway.
Like everything else in life, it is a trade off.
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On both my Langmuir and STV, I actually stuck with the automatic voltage setup.
From what Iâve gathered though, many like to run Nominal only when cutting thin material. This is mainly because -
- Material will flex when the torch probes said thin material especially if itâs in an area between the slats or at the end
- Material can have a bow in it, especially larger sheets
I donât cut anything thinner than 16 gauge, and even then I rarely ever cut 16 gauge so for that reason I run the automatic height setup.
But if I ever did run 18 gauge or thinner, Iâd definitely run Nominal.
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Unsure what you mean about âragged cuttingâ when using Smartvoltage.
This has some small details that cut without issue on a Crossfire Pro.
This one was pretty small as most of this is line work.
This last one isnât a great example due to some of the scales lost, but thatâs user error on my part for having used the wrong tool; I used a 45A tool from my library while running a 60A nozzle on my actual torch. I remember it like yesterday because I told myself to check my nozzle before I commit to cutting. Newbie mistake years ago.
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I was referring to nominal voltage. Since there isnât any delay capability (at least as far as I have been able to discover, have you found a way?) the thc voltage will lock in immediately upon torch firing, and since the pierce is being generated, the pierce hole widening and the cut starting all at the same time, the actual arc voltage will be swinging wildly during these few moments.
With the nominal thc voltage locked in from the get go, the torch will rise and fall during this short period as the thc tries to compensate for the varying voltage, thus the cut wonât be very good at this point.
Once the torch flame has stabilized and the kerf is established, the arc voltage is consistant and the thc then compensates for any arc voltage change.
With smart voltage, the thc isnât âturned onâ untill after everything has stabilized. The default distance delay is 0.5" but you can change that if you want.
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There isnât a need to confirm your cut height because Hypertherm has determined that that should be the target voltage when everything is correct. Now the smart voltage you need to have the correct height so fire control doesnât set the voltage wrong during the sampling period.
My experience with a 65 non sync has been that I prefer nominal most often when working with thin material that has a tendency to flex during the IHS cycle. I have seen several times that smart voltage would set the wrong voltage because of flex. Now with well worn but not worn out consumables smart voltage will cut a little better because the voltage required to maintain the correct cut height can vary some.
I believe if you pay attention to the voltage that smart voltage locks in using the correct cut height it will be very close to what Hypertherm posts as their target voltage.
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Ok so someone explain, if running nominal how does pierce height get set?
does that work just like if you are running smart voltage?
The ihs touches off to determine where the material is then moves up to the pierce height. So yes the same. Now if it flexes the ihs can zero on the material in a flexed state the go up to a set pierce height and the material follow because zero was set at a incorrect place. That can cause the torch to fire and set smart voltage incorrectly.
The thc has nothing to do with the pierce height as a whole.
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IMO, and this is based on my system where it only uses a set voltage for determining cut height, I donât see why you would use anything BUT nominal voltage. The voltage is based on the torch current, cut speed, and material. As far as I know, that doesnât change throughout the entire sheet of material so nominal makes sense from that perspective (do a test run on a flat piece at the proper cut height and record the voltage - easy peasy!)
The second factor that would steer me from âsmart voltageâ is that, as a retired electrical engineer, I have a very poor opinion of the quality of the CrossFire Torch Voltage sensing circuit. Itâs noisy and has poor electrical isolation. Neither of these are conducive to reliabliy reading the voltage during the reading of the âsmartâ voltage.
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@TomWS I agree about nominal. Is it possible it seems to be in my experience that the voltage will change some as consumables wear. I believe smart voltage is valuable with aging consumables ( not worn out though).
I have also watched the locked in voltage when using smart voltage and fire control reports very close within a few volts of what Hypertherm puts out as a target. All this is when stars are in complete alignment. I agree the setup langmuir uses isnât the best out there I donât believe it is that unreliable. Seems every time I see a issue it operator induced. I also believe thatâs what happens most often when we see people with issues.
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Good points, especially about wearing consumables. You certainly have more âmilesâ on that system than I do (like 0)!
Still, it seems to me, if you know what the voltage SHOULD be, why leave it to chance that the initial sample, shortly after pierce, is the correct value?
The smart voltage concept is sound, but it reqiures a highly reliable system to get it right every time.
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I agree completely I use nominal 95 percent of the time. It has always done me well.
I recently cut 1000 washers out of 1/4 material (2x4 with 2- 5/8 holes). 500 with 45 amp consumables and nominal voltage except the last 150 or so that I did with smart. The other 500 was with 65 amps and smart voltage all the way. Cut quality was near the same with both. The 65 amp nozzles was in better shape than the 45 at the end.
As a whole I like nominal I also think smart voltage is fair. I certainly recommend nominal for thin material due to flexing during fire controls IHS.
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good info guys thank you, I am going to cut some 1/2â today. maybe I will do some comparison between the two. This is all new to me as I have always used smart voltage. I hopefully come back with more data.
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You said nothing new that most here donât already know.
My question was regarding your comment about raggedy cuts, and how apparently smartvoltage is the cause of this.
Yet lots of others (myself included) have cut many things successfully without any raggedy cuts regardless of how intricate something is.
I shared pictures to further my claim.
What youâre having issues with is CAM, and not related to nominal or smart voltage.
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Keep in mind that as your electrode wears, your cut height will be slightly altered.
This is because the nozzleâs height in relation to the steel plate will shrink slowly as the hafnium in the electrode wears down.
Hypertherm assumes the end user will perform test cuts every couple of hundred parts and adjust their nominal voltage as the cartridge wears down.
I say this as someone thatâs spoken to engineering at Hypertherm direct, he said your voltage will need to be adjusted slightly to maintain the same cut height over time.
This is mainly why I stuck with smartvoltage.
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Hi Kwikfab, I think you are mis-reading my post. The reference to a raggedy cut was with respect to nominal voltage, not smart voltage.
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Nominal is all I use on my XR table with Hypertherm cutter, never had an issue.
You can check cut height using nominal voltage, pause program once it starts cutting a couple inches on a test cut you design and post process.
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I did misread, youâre right.
Can you share these cuts? Iâm interested in seeing them.
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To be perfectly honest with you, I havenât tried nominal voltage yet. As I stated in my very first responce, I am contemplating trying it. I am researching the pros and cons of it, and everything I have mentioned is a result of this research; it is âbook learningâ only.
I do mostly artwork so a wiggly 1/2" or so to start, wouldnât be very satisfying. Like you, I will probably stick with smart voltage, that is until I discover a way to put in a delay like the smart voltage has.
Not being one to leave well enough alone, I am always âchasing perfectionâ.
Cheers
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Honestly I donât believe you will find this is correct. I do tons of artwork and most always do nominal. I donât doubt that you have read this somewhere do you remember where I would like to read deeper into whoeverâs reasoning.
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