Anyone have a plasma cutter?

[davesisk]

I've been looking for a short time, and there seems to be a huge difference in price between some of the name brands vs. some of the off-brands. For instance, Harbor Freight has a Chicago Electric (their house brand) 35 amp plasma cutter with a 40% duty cycle for $899. A similarly-equipped Miller or Lincoln (or even ESAB) is almost twice as much.

There's also a 30 amp plasma cutter that's a discontinued Chicago Electric model on Ebay right now at what looks like might be a pretty good price.

Specs on both of these say they will cut up to 3/8" steel plate. At this power-level, should I expect the cut to be really neat, or jagged and ugly?

Does anyone own one of the Chicago Electric plasma cutters? Any problems with it? I started my welding experimentation with a $150 Chicago Electric flux-cored wire feed welder, and it was pretty crappy. I replaced it with a small inverter-based Chicago Electric stick welder, and I'm pretty impressed with it. I have an ESAB Heliarc 161 AC/DC TIG welder now also, and I love that one machine! I'm thinking (based on the quality of the CE stick welder that I have) that these seem to be reasonable levels of quality, at least plenty good enough for home workshop. I favor the inverter-based devices because they tend to be small and lightweight, and usually have low current draws compared to their transformer-based counterparts...these characteristics are important to me in a home workshop: I can run things off a 30-amp 220V dryer circuit.

Anyway, please share your experiences if you have any.

Thanks!
Dave

 

[johnbilt]

Hi Dave

I purchased a plasma cutter last year. I ended up choosing the Hypertherm 1000, which is a 7/8" machine. I wanted to be able to cut 1/2 and 3/8 steel cleanly.

I experimented with the smaller 40A machines, which are generally rated at 1/2", but found that this is optimistic. I demo'd the Thermal Dynamics Cutmaster 50 and the Hypertherm 600. The welding shops generally indicated that these were superior to the Lincoln/Miller line. I would recommend a minimum of 40A output for cutting 3/8" with reasonable quality.

Of course, these machines cost in excess of $1000 plus. I can tell you that the Hypertherm brand is an excellent quality machine. I personally believe they are the best available. I eventually reasoned that I would rather spend $$$$ on a machine that did what I wanted, rather than spend $$ on something that didn't. I had to grit my teeth at purchase, but I have been happy with the performance.

If you are looking for an inexpensive machine, I think you are on the right track to search Ebay and Harbor Freight. I would be sure to get a warranty and see where the nearest service center is located. Also be sure that you have a reliable source for consumables.

My favorite and excellent source for this type of equipment is welders-direct. They are based in the NW and offer free shipping in the great USA. They carry the major brands and models. Give them a call and ask about the equipment; They are nice people !! (I'm not affilliated with them in any way, I have purchased several pieces of equipment from them, and I have found them to be very professional)

Central Welding Supply

Good Luck /forums/images/graemlins/smile.gif

 

[Taylortractornut]

I dont think Id go with the Chicago electric stuff. My neighbor bought one a few years ago and tips were hard to find the import store here had them one time. I have a friend with a 2100 dollar Hyper therm Ithink I cant remeber exactly and it will cut up to 1 inch and 1/8 as quick as you can move. His is inverter based i think it weighs sixty pounds. I belive their smallest machine is about a 1000.
I dont mean to knock the Chicago electric stuff but 800 is lot of money to me to not have a parts gaurantee. My neighbors machine could cut 5/16 at the most. Hed come use it in my shop when i fixed his equipment and it wasnt handy as parts took 2 weeks to get there.

 

[GaryM]

</font><font color="blue" class="small">( Also be sure that you have a reliable source for consumables.)</font>

Pardon my ignorance, but what exactly are the "consumables" for a plasma cutter? I have a wire feed welder and the consumables would be gas, wire, and the occasonal contact tip.

My slight knowledge of plasma cutters is that they use compressed air. Are there electrodes that hold the arc the gas passes through to make the plasma? If that's the case, how often do they need to be replaced?

 

[JohnMiller3]

About 10 years ago, I attended a bankruptcy auction. On my cell phone, I called a friend and asked if he would be interested in this “XYZ” plasma cutter. He laughed and told me he’d take it for no more than $125…

So, later that day, I drove up to his garage and he just about fell down when he saw boxes and boxes of tips/hoses/tanks/replacement parts etc. along with the plasma cutter and wheel cart… I just purchased for $110… /forums/images/graemlins/smile.gif

I don’t remember the brand name… but the last I knew… everything was still working fine… /forums/images/graemlins/wink.gif

(My buddy, told me later, he was joking about the price and never dreamed of the unit being sold for such a give-away price… /forums/images/graemlins/laugh.gif)

 

[johnbilt]

Hi

The consumables for my Hypertherm are the contact tip and the nozzle insert. Please forgive me if I am using an incorrect part nomenclature. That's what I call them....The other machines I have seen have similar consumable parts.

The tip and nozzle longevity depends on how many starts and stops, humidity of the compressed air, thickness of metal, poor technique in shorting tip to workpiece, etc...

I used the same tip for quite a bit of steel cutting. My tips wear faster with aluminum. It is softer and tends to spit molten metal back into the tip. Not so good ! Travel speed and current setting are everything.

The Hypertherm features a standoff work nozzle which makes it possible to drag the tip directly on the material. This way a straight edge can be used as a handy guide. Many other machines require the operator to maintain a 1/8" to 1/4" distance from the material. I found this to be more tricky. Also, the Hypertherm has a great torch setup with a flip down safety trigger.

I just came in from the shop cutting 1/4" alum plate for mounting a boat motor. Cuts like butter...

Good Luck
John /forums/images/graemlins/smile.gif

 

[Hambone]

We had a Thermal Dynamics and were not pleased with it. We had sent it back to the shop several times. We finally replaced it with a Miller. Parts and service are readily available.

Which ever brand you decide be sure and put a good water seperator on your air hose. Very important!!

 

[jimgerken]

From my experience, whatever they rate the unit at, cut that figure in half for what it will cut fairly cleanly. Also, consider duty rating. For instance, my Thermal Dynamics Cutmaster 38 is rated for 3/8" cut, but it will not pierce 1/4", so for above 3/16" you must start the torch from an edge or existing hole. The cut quality in 1/4" is not that great, pretty slaggy. To cut a 8" diameter hole in 1/4" material required three sessions, due to the machine stopping to protect itself from heat buildup. It will cut for about three minutes continuously at full power, then must have a minute to cool. On thinner materials, (90% of my "work" is in 14 gauge, 0.078", stainless), the quality is excellent. FWIW...

 

[em14]

Jim,
What is the duty cyle per the mfr on your cutter? Is it close to what you are experiencing? Also, the thickness that your machine is rated at, if I understand what you are saying, is about twice what you can punch throught, but, can it cut the rated thickness once you start, say, on the side of the metal. Are your observations including mild steel or just Stainless. I'm trying to decide whether to just use Oxi Ac or take the plunge into plasma.
Leo
Thanks,

 

[jimgerken]

From memory, the rated duty cycle is 35%. I am not sure how this relates to the real world. It will run several minutes at full power and then stops and can be restarted after about a minute. The material being cut does not matter, except that to cut stainless you must travel slower (so maybe it won't cut as thick of stainless as it will mild steel either, but I havent tried to cut any thicker than 0.090" S.S. . The 8 inch circle was in mild hot rolled steel. Plasma sure does nice things with thin materials. The sheets do not heat up nearly as much as Oxy/Gas processes. Until I can afford a lazer I will need to own a plasma unit. Just kidding, I will surely never afford a lazer. /forums/images/graemlins/grin.gif