Metal cutting - oxyfuel cutting, plasma cutting, machining, grinding, and other preparatory work.
ex framie
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cfiifly wrote:
cfiifly wrote:I've never used a plasma cutter. Harbor Freight (HF) has a 40 amp plasma cutter on sale this month (Aug 2016) for $399. RF start. Advertised as cutting 5/8" - 3/4". WIll this cutter blow holes/hack up 10-18 gauge, or will it cut thin metal cleanly? Also - if you own or have experience with this plasma cutter, please give me your recommendation on whether or not I should buy it. Thanks in advance for your help.
Thanks to everyone who responded to my request for help. You gave me good food for thought, but no one addressed my question about cutting thin metal with a cutter powerful enough power for thick metal. What happens when thin metal is cut with too much power? Does it cut smoothly, or does the cutter mutilate the thin metal cut line?
Adjust it correctly and they do thin material quite well.
I have a Chinese plasma, I'd love a hypertherm but the govt here won't let you sell children or kidneys.
Read its manual, get some thin material and have at it, hand piece angle, travel speed, amps and airflow/pressure will all have an effect so a bit of practice is the go, sound familiar?
They do eat consumables so get a supply of those and a decent water trap for the compressor, dry air is an important requirement.
Most Chinese plasmas are decent units and getting better, hypertherm quality? Nup, useful? Yep, will they cut the thickness claimed? Sometimes. Are they capable of being thrown into heavy everyday use and surviving? Not yet.
Suitable for hobby use? Yes.
So there you go, isn't choice (or too much of it)wonderful.
Cheers
Pete

God gave man 2 heads and only enough blood to run 1 at a time. Who said God didn't have a sense of humour.....
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Agree with framie - just go in with your eyes wide open, buy plenty of consumables and be prepared to shrug it off if the machine farts, spits and dies one day.

If you're not using it to make a living you will probably be okay.

I have a plasma onboard my Chinese welder. The whole machine has amazing backup by the local seller so I guess I have an advantage there.

I spent a lot of time practising with various amps on many different thicknesses of metal and I'm very happy with the results. It's not a tool I use all the time but I have to say that for those times I use it, I'm very glad I have it as it is often the only tool that would manage the job in question.

Hope this is helpful.



Kym
cfiifly
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jimcolt wrote:If a plasma cutter is rated for 1/2" material...it can certainly cut all the way down to the thinnest materials. If there is a choice of consumables.....such as nozzles (some call them "tips") that are rated for 20 or 30 amp cutting....then you can turn the amperage down, install the low amp nozzle....and this allows you to cut at reasonable speeds for smaller detail on thinner metals. If there is only one nozzle (tip) available...then you can still turn the amperage down and cut thinner materials but expect more dross and a wider cut kerf (width).

You will find that the major brands (like Hypertherm) have a choice of nozzles such as Finecut for under 10 gauge and 45, 65, 85, 105 and 125 amp nozzles for better results on thick materials. Kind of like matching the correct mig wire to your welding application for best results.

The low cost imports cut metal. They have a reputation for reliability issues and for eating consumables (nozzles, electrodes (tips) at a fast rate......while the more expensive major brands are designed for years of use, and lower operating cost based on longer consumable life and better overall cut quality. Typical nozzle life when cutting 1/4" steel at 40 amps with most imports will be about 1/2 hour of arc time with roughly 100 to 300 starts, depending on operator technique. A Hypertherm Powermax operating at 40 amps can easily achieve 2 to 3 hours of arc on time and between 1000 and 2500 arc starts. The import consumables cost less to buy (mass produced in China), the Hypertherm consumables cost far less to use.

Last, but not least. Hypertherm and the other major brands provide excellent product support, detailed operating manuals and a factory number you can call with questions or troubleshooting assistance.

I understand the lure of low price.....however don't expect the same cut quality, operating cost, ease of use and reliability with these units. They will cut metal!

Another option for low price is the used market such as Craigslist. Look for Powermax600, Powermax30, Powermax45, Powermax1000 as good used Hypertherm systems that can often be had at reasonable prices.

Jim Colt Hypertherm
Thanks Jim! EXACTLY the kind of information I was looking for. My normal propensity is to always buy for the long run. I'll try the Craigslist route first, but I'll probably buy new. Thanks again for the outstanding reply!

MikeM (cfiifly)
cfiifly
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soutthpaw wrote:Go to weldingweb.com and contact mechanic416. Or call George at georgesplasmacuttingshop.com I think is the address. He repairs Chinese plasma machines and knows them inside and out. You can tell him Southpaw referred you. The other guy that can result explain the differences is Jim Colt he is on this forum too. 37 years working for Hypertherm. He knows his stuff. It will definitely cut what you asked about. Different people have different definitions of "clean cut"
Thank you for the recommendations. Jim Colt replied to my request with an outstanding rundown. His expertise was obvious, and his suggestions have given me confidence in knowing what I should be looking for. Definite "Kudos" to you for suggesting him. Thanks!

MikeM
hey_allen
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Buying off of Craigslist is an exercise in patience and luck, but sometimes the luck part pays off.

I found a new, still in the various shipping bags, Miller Spectrum 375 for $800 on the local Craigslist, from a soldier who was about to separate from the Army, and his Mrs informed him that their family was growing again...
-Josh
Greasy fingered tinkerer.
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