Welding Tips and Tricks

Christmas comes early. Received my Stel S300 plus a mystery box








Conductors are tiny! Very little amperage needed.





Checking the voltages. Nicely balanced, coming from the 3-phase transformer that is being fed from the 30HP rotary phase converter











Can't wait to put it through it's paces.

Stel rates the machine to be able to use 8mm (5/16") carbons.....hmmm





what do y'all think?

I think the * trumps the top of the chart.

Poland308 wrote: ↑Sat Sep 25, 2021 6:19 pm I think the * trumps the top of the chart.

How so?

Maximum electrode footnote.

Maximum electrode size....... for 100% duty cycle. Seems that is just a reminder in the event that the user wants to maintain 100% duty cycle.

The lil' S300 handled the "big" 8mm carbon rods pretty well. I had it turned all the way up to 300A in gouging mode.

Interesting, I have no arc gouging experience but it certainly didn't look inconsistent like it was struggling. Did you get this machine to spare your HTP Invertig 400 the abuse from arc gouging? Or did you just want to see if a dedicated stick/gouging focused machine would stick weld better than the Invertigs? I'm just curious because the Invertigs seem to have all the typical stick welding luxuries, hot start, arc force and will run 6010. Though they're not rated for gouging, my Lincoln Invertec 275 specifically was but it didn't have a specific gouge mode, it just specified to turn the arc force up all the way.

I never really gouged with mine simply because 1 the air compressor I had would provide all of about 15 seconds gouge time, and because I've heard gouging is destructive on machines and because it welded so nice I didn't want to risk it.

300A is at the low-end for the larger 8mm carbons, but it did quite well, IMO. I'm basing off of what I have seen on YouTube and the results that others have gotten. I'm sure it would have been better with another 100A, but then again I can always drop down a size, no big deal. I never really thought about gouging with the big TIG or MIG, but I think they would be fine.

I've also read about gouging being "hard" on machines, but call me naive, I don't think that gouging (arc) is the root cause of the problem. I currently feel like the root cause of tiring-out welding machines by using them for air arc gouging is simply because it requires so much amperage, that most machines have to be run wide-open to light up decent-sized carbons, and thus possibly exceeding the duty cycle and the operator not knowing. With a standard machine that only shows the over-temp light, it might already be too late since the over-temp light is not always connected to the actual duty cycle rating of the machine.

https://forum.millerwelds.com/forum/wel ... ng-machine
https://forum.millerwelds.com/forum/wel ... ng-air-arc
https://forum.millerwelds.com/forum/wel ... rc-gouging
https://forum.millerwelds.com/forum/wel ... c-settings
https://forum.millerwelds.com/forum/wel ... 17-air-arc


The real kicker is going to be when I parallel the S300 with one of the other machines to bump up the amperage for gouging with the 8mm carbons! Oh and I got this machine because the tough decisions in my life go as follows: buy machines and other toys.....OR....spend the money at Hooters?

Oscar wrote: ↑Tue Oct 05, 2021 7:49 pm I've also read about gouging being "hard" on machines, but call me naive, I don't think that gouging (arc) is the root cause of the problem. I currently feel like the root cause of tiring-out welding machines by using them for air arc gouging is simply because it requires so much amperage, that most machines have to be run wide-open to light up decent-sized carbons, and thus possibly exceeding the duty cycle and the operator not knowing. With a standard machine that only shows the over-temp light, it might already be too late since the over-temp light is not always connected to the actual duty cycle rating of the machine.

Yup, that's been my theory too, very few machines at all are intended to be ran wide open at 100% or close to it but that's exactly what people tend to do when gouging, they rarely gouge with a smaller electrode and less amps than their unit can produce, and only if they have to for a specific reason. A machine may very often give a 100% duty cycle at a specific amperage, often corresponding with the name of the machine XMT 450 for example, but they're capable of putting out far higher current at less than 100% duty cycle. I think when this subject came up also, a machine with a 100% duty cycle, or any percentage duty cycle also has a corresponding voltage with it. I've seen references to gouging requiring higher voltage than stick welding to maintain the same current, and a 100% duty cycle machine at 300 amps, 30V wouldn't necessarily be a 100% duty cycle machine at 300 amps and 38 volts. That's just a theory of mine, though that extra wattage has to come from somewhere. One would assume a modern high end inverter machine would be more than capable of either limiting the voltage to not exceed a certain number when maxed out to avoid damaging the machine or would be built with components that could handle running maxed out at a few higher volts than one would typically experiencing stick welding and heat buildup would be the main issue, so either way, you're probably right about just running them far past the duty cycle over and over until they're cooked.

It causes a lot of smog and slag spray.
Breathing protection is a must.
It very difficult to keep the power source away from it all if you have a fair bit to do.
We take covers off ours and blow them out fortnightly and a lot crap comes out. Rarely do you air arc without grinding so it can add up to a crap enviroment for tig welder.
Nice gouging Oscar.

sbaker56 wrote: ↑Tue Oct 05, 2021 10:49 pm One would assume a modern high end inverter machine would be more than capable of either limiting the voltage to not exceed a certain number when maxed out to avoid damaging the machine or would be built with components that could handle running maxed out at a few higher volts than one would typically experiencing stick welding and heat buildup would be the main issue, so either way, you're probably right about just running them far past the duty cycle over and over until they're cooked.

Also on old transformer machines the 'overheat' cutoff really was just something like a bi-metallic contact on/in the transformer core that would open when it got above a certain temperature.

Now, that's not terribly accurate temperature-wise in many cases to start with and gets worse when it's not regularly (re)calibrated so it may well cut off when the core and windings have gotten a bit too 'toasty' for their own good.

Also on big transformers you get the effect of hot spots where there may be areas on the transformer core and windings that are MUCH hotter than where the overheat trigger contact is and as a result it starts cooking the insulation..

So on these I can well imagine that they simply 'wore down' a lot quicker when used to gouge and didn't work quite as well anymore when used as a normal welder.

On modern inverter machines, and especially better desgined ones, this is much less to not such a problem. The active control of voltage and current and heat management means that it's much less likely to wear or develop internal damage on an 'overheat' or 'duty cycle exceeded' situation as a pure transformer machine would.

Of course as it's a process that's running a machine at 100% capacity for a long duration it's still a very good way to find the 'weak' designs when the magic smoke comes out of these

But on any decent (brand) inverter machine I would not expect it to have any longer term issues when used for gouging.

Bye, Arno.

Your term "magic smoke" reminds me of my days studying ECE

I have never heard of Stel. Is this another knock off cheap brand?
-Jonathan Lewis

Superiorwelding wrote: ↑Tue Oct 26, 2021 9:37 am I have never heard of Stel. Is this another knock off cheap brand?
-Jonathan Lewis

It's the manufacturer HTP contracts with for their own welders. Basically it's an in house/country HTP. Correct me if I'm wrong Oscar

Correct, sbaker. The are the actual manufacturer of most of the HTP machines, based out of Italy. Definitely not cheap, lol. To the rest of the world outside of the US, they are to those countries what Miller/Lincoln are to the USA.

https://www.youtube.com/user/StelWelding/videos
http://www.stelgroup.it/?lang=en

opened it up to blow out the dust. Fully enclosed "wind tunnel" design. I like it.











Beefy.

Looks very nice. 200A @ 100% would cover about 100% of what 99.9% of people need.

On the note of 3 phase, I'm doing an application right now to see about getting 480 3Ph in here. Looking at buying a machine that requires 1200A/480V service. I can't wait to hear what that's gonna cost.

BugHunter wrote: ↑Thu Apr 28, 2022 9:01 am Looks very nice. 200A @ 100% would cover about 100% of what 99.9% of people need.

On the note of 3 phase, I'm doing an application right now to see about getting 480 3Ph in here. Looking at buying a machine that requires 1200A/480V service. I can't wait to hear what that's gonna cost.

That's a lot of percentage right there!

Buggy, did you hear that Oscar is financing all 3 phase installs?
Keep me posted, I'll make a road trip when ya get 'er done.

1200A?? I'm guessing a Subarc machine? I can't imagine anything else that could require that many amps, gouging probably, but on WHAT?

sbaker56 wrote: ↑Fri Apr 29, 2022 9:08 pm 1200A?? I'm guessing a Subarc machine? I can't imagine anything else that could require that many amps, gouging probably, but on WHAT?

No welding equipment, it's a machine. BIG machine. Has BIG motors on it. Just the main motor for it is 600HP. I'm told just that motor pulls around 750A continuous. The smaller ones are obviously way less, but it all adds up.

My power company application asks about other loads, such as lighting. I wanted to reply, can you say insignificant!

BugHunter wrote: ↑Mon May 02, 2022 12:36 pm

sbaker56 wrote: ↑Fri Apr 29, 2022 9:08 pm 1200A?? I'm guessing a Subarc machine? I can't imagine anything else that could require that many amps, gouging probably, but on WHAT?

No welding equipment, it's a machine. BIG machine. Has BIG motors on it. Just the main motor for it is 600HP. I'm told just that motor pulls around 750A continuous. The smaller ones are obviously way less, but it all adds up.

My power company application asks about other loads, such as lighting. I wanted to reply, can you say insignificant!

Jesus Christ

I"m curious to see what the electric company says the electric bill will be. Commercial electric uses a demand billing, which if you're not familiar, means they charge you demand for the entire month at the maximum rate of consumption, as if it were running 24/7. That's the part that kills you if you're not running the machine all day. It's not insignificant... Deep in 5 figures per month. The idea is that if you pull that power, they had to provide infrastructure to provide it, so here's your bill. It's enough that I'm contemplating running the machine for a month, shut it down and "unplug it", and wait till the next billing cycle begins before running it again. At least till I can build up enough business to keep it busy.