Plasma Cutters anyone?

[wroughtn_harv]

The metal templates to screw up consumables. But silly me I figure that's the reason they call them consumables./w3tcompact/icons/laugh.gif

I like the soapstone line. Something to keep in mind is it's a lot like driving. You're focusing ahead of the torch and not right on it. Another thing I've found is pulling is easier to keep straight than sweeping.

The biggest thing I've found to help is accepting that it isn't magic. It doesn't take something special that only a few blessed folks can do. It's just a matter of doing it and understanding that improvement comes with practice. And practice means you gotta.

I'm learning a new technique today on bending material. If I get the time I'm going to make a couple of jigs anyone can do just about. Then they can do things they hadn't considered doing. That's always fun.

 

[micromike]

brantley

I tried cut and past to the Navy site you listed to read about the oragnepeel technique that has been discussed here. I'm getting a site not found. I did find the Navy site but can't seem to navigate my way to the area you posted about. Could you please check your URL or offer any additional instructions to get to this site? tia.

Mike

 

[brantley]

I just checked the URL and it worked for me. The url was broken up into two lines. You might try grabbing each line separately. A linefeed might have gotten included if you tried to grab both lines at the same time. Below is the url again. I looked at the posting
faq this time. So maybe it will be easier to reach.

<A target="_blank" HREF=http://www.advancement.cnet.navy.mil/products/web-pdf/tramans/bookchunks/14251_ch3.pdf>http://www.advancement.cnet.navy.mil/products/web-pdf/tramans/bookchunks/14251_ch3.pdf</A>

 

[DavidInNH]

Try this <A target="_blank" HREF=http://www.advancement.cnet.navy.mil/products/web-pdf/tramans/bookchunks/14251_ch3.pdf>brantley's url</A>

-david

 

[micromike]

Worked great guys. Twice! A lot of good information there, printing it out now. Thanks for sharing, and responding.

Mike

 

[wroughtn_harv]

Ditto!

 

[Anonymous Poster]

I have a Miller plasma cutter. It is definitely cool, but pretty wimpy unless connected to 220V. If you are not making your living cutting metal, I bet a torch would do the trick. The torch can be used to heat rusted and stuck bolts and nuts too. The plasma cutter will not negate the need for a torch, but if you are not cutting too much stuff you can live without a plasma cutter.

 

[JohnInCA]

texasjeff,

What do you think of the Plasmacam unit? Solid? Work well? Is the software good? I have their video and printed material, and it looks like a fun tool.

 

[TexasJeff]

I like the plasmacam. Good software but for me a long learning curve. It does everything it said it would so far. I have only had a couple of problems. If you get one follow the wiring directions closely esp the limit switches. I thought I did but it cost me 2 drive belts at $10 each.(that was the biggest suprise for me the cost of the tiny drive belts) I did buy an extra hand torch for the plasma cutter because it was a hassle to install or remove the torch out of the cutter and get reset correctly

 

[centex]

This thread is going to cost me some $$. I am going to buy a plasma cutter. Can't get around it this time. One dealer is trying to sell me a Thermal-Dynamics 38XL for $1300 and another wants to sell me a Hypotherm 600 for $1750. The Hypotherm is a larger unit hence the higher price. He told me this price is $150 over his cost so it is probably a good price. The Thermal-Dynamics dealer is one I have done business with for many years but they never give me a discount.

Both dealers clain that their product is the best on the market. Since I know nothing about either except that Thermal-Dynamics is a Thermadyne brand, I need some advice on which way to go.

One of my concerns that both assure me is not a problem is the long term availability of consumables. My fear is that I will buy one of these products and not be able to get the consumables in two years. I bought Linde TIG and MIG welding machines in 1981 because they had been around for many years and their TIG machine was the most advanced of its kind at that time. Union Carbide sold off the welding business a couple of years later. Forutnately I had stocked up on consumables for the MIG torch and there are lots of copies of the TIG torch so I have not had a problem but at the rate welding companys are comming and going I worry about anyone being around in 5 years.

 

[wroughtn_harv]

Don I highly recommend the plasma cutter. The consumables are higher than a cat's back that's for sure.

I've got an ESAB that'll severe five eighths but only cut half inch. I would be hung out to dry without it. I also have a Miller Spectrum 1000 which will cut one and an eighth. But it is set up for three phase so I haven't hooked it up to power yet.

If you're interested I can do some checking around up here for you about price. I know Ron got a heckuva quote on a Miller that'd cut three eighths from my supplier.

I'm gonna look through some pictures I had taken the other day of me using the ESAB. If I can find them I'll post them. If that doesn't bring you to tears then you're one hard hearted son of pisolever packing mama.

 

[wroughtn_harv]

This is three sixteenths plate that started out five by six. I picked it out of drop cause it was odd shaped, weathered aka patina or character, for making some plates for trusses on an open cedar ceiling a friend has.

Ignore the hansome operator of the torch. But do notice there isn't any clamps on that quarter by two straight edge. And please everyone don't try this at home. You're watching a professional in action. /w3tcompact/icons/laugh.gif The camera operator has the safety gear. /w3tcompact/icons/laugh.gif/w3tcompact/icons/laugh.gif

What I've found works best for cleaning slag after a plasma torch cut is a chisel. Not sharpened like a cold chisel where both sides come in to a point. But like a the edge on a wood chisel where one side is flush flat and the other is sharpened down to it.

I'm not saying to use a wood chisel. What I have is a cold chisel I've reshaped in the form of a wood chisel just for cleaning slag. If you slide the chisel along the face where it contacts the slag pushing it back towards the cut you will be surprised how fast and clean it all happens. It's faster and safer than using a grinder. It's also cheaper since all you're spending is energy and an edge of the chisel you need to refresh once every generation or two.

If you look behind that fine figured man with the great personality you will see a chop saw. It isn't just an old chop saw btw. It's welded down into place where it cuts perfect forty fives each and every time.

Now if you can't dedicate a chop saw to just forty fives then you can do what I did before I could dedicate one just for that.

I found the perfect forty five on the saw. Then I drilled through the fence and frame on the saw so I could bolt it when I needed a forty five cut.

You can't trust the marks on the saw. And if you don't have it welded or bolted in place the fence it's going to crawl. Your forty fives are going to become forty fours or threes and then twos. I use a speed square against the blade to orient the fence. It just makes things easier.

 

[wroughtn_harv]

Don this cut is being made with a steady fast pull. What I've got going is first and foremost I'm not exposed to the light from the torch. I am dragging the tip against the steel. So I have that and my hand shielding my eyes. All I'm doing is trying to keep a smooth movement.

I'm only using the straight edge as a guide. I'm not putting any pressure against it at all so I don't have to clamp it.

Another thing that's really nice about a plasma I've found is I don't have to worry as much about torch speed. If I hit a corner and I need to reorient my body to continue the cut I keep the torch going and do so. It isn't like with a gas torch where you change the whole dynamics of the cut with a change in torch speed.

Another thing some of you might like is my sawhorse. It's made of lightweight round pipe. The top is thirteen inches wide and it's six feet long. There's a shelf underneath for holding things when the job requires for the work bench to also be a tool holder for the tools you're not holding at the moment.

Sitting on it in this picture is a piece of five feet by six feet three sixteenths steel. I'm not sure just what it weighs but when bro in law helped me put it on the horse he got that look in his eye like he'd just lost six years of good *** life when we lifted the plate.

I have two of them, saw horses, not *** lives, and find them handier than a pocket on jeans.

 

[Anonymous Poster]

I've had my ThermalDynamics for about 8 years now, and the only problem I had was the cooling fan burned out. As far as consumables, if any of the major manufacturers crap out, I'm sure somebody will supply consumables that fit the machines.
There are already 3rd world consumables being sold for most of the major brands, which aren't worth the postage to get em.
Linde, heck, I still have 3 P&H heliarc machines, just can't wear em out, and I think they will still be running when some of the new machines are on the scrap pile.

 

[brantley]

I was in the same position of deciding on getting a plasma cutter over the last couple of years.

I read a lot of the opinions on rec.crafts.metalworking
about both units. The overall impression I got was that the Thermal Dynamics produced a better cut and narrower kerf, but the Hypertherm had better consumables life.

Do a search on Google groups for Hypertherm and Thermal Dynamics and you will find lots of opinions about both. I ultimately went with the Hypertherm 600 and have been very happy with the performance.

I paid 1790 for my machine. I have seen the Hypertherm 600 listed for as little as 1600 buying over the internet, but I wanted to have local service and support. I also spent an extra 90 for a filter. The filter inserts look like a roll of toiletpaper. One thing consistently mentioned is to get a good quality filter.

I am sure whether you get the Thermal Dynamics or Hyperther, you will be happy with it.

 

[EdDekker]

I purchased a Hypertherm 600 recently. I haven't done much with it yet, so I can't say much about its operation.

There is a lot of good information on the newsgroups sci.engr.joining.welding and rec.crafts.metalworking that can help you with your selection. A google search, for example <A target="_blank" HREF=http://groups.google.com/groups?as_q=plasma%20&as_oq=Hypertherm%20Thermodyne%20TD%20Thermal%20&safe=images&ie=UTF-8&oe=UTF-8&as_ugroup=sci.engr.joining.welding%2C%20rec.crafts.metalworking&lr=lang_en&num=100&hl=en> google search for Hypertherm and TD Plasma</A> will bring up a lot of good information and some direct comparisons about these units. The consensus is that these are the two best brands and that either is a safe choice. The Thermal Dynamics has a slightly cleaner cut and the Hypertherm can cut thicker metal at a given power and has better consumable life.

One major difference between the Thermal and Hypertherm Plasma cutters is the mechanism used to start the arc. The Thermal uses a high frequency, high voltage arc to create a spark and initiate the arc. The Hypertherm uses a lower voltage pilot arc to initiate the plasma arc. The High Frequency from the Thermal Dynamics style will crash a nearby computer. It will also interfere with radio/tv reception far more than the Hypertherm style. If you may someday build a PC controlled cutting table you should get a Hypertherm style Plasma Cutter.

Torchmate has a web page with advise on selecting a Plasma Cutter <A target="_blank" HREF=http://www.plasma-cutter.com/selection.htm> link </A>.

My decision came to deciding between a Hypertherm 380 or a Hypertherm 600. I decided to go bigger. The 600 has a torch which can be dragged while the 380 needed to be kept above the work.

I can offer a few random thoughts from my research and a surprise after I bought mine.

Make sure you can power the plasma cutter. The Hypertherm 600 draws 50 Amps but Hypertherm recommends a 100 Amp slow blow fuse (not a circuit breaker) on the circuit (or a generator with at least an 8000 VA capacity). link

 

[centex]

I have decided on the Hypertherm 600. This was after reviewing the posts on the recommended links. I had to add a 125amp subpanel in my garage to power a Heliarc welder so I already have the power there. This was a supprise to me also. I had assumed that this 250 amp welder would not use much more current than the 225 amp Lincoln buzz box that I had. I had to have them put a power factor correction kit in the welder to be able to get by with a 125 amp circuit. It needed 150 amps without the PF kit. By the way I used a three wire cable and a separate ground wire to wire in the subpanel because it was less expensive than buying 150 feet of service entrance cable in this size. I assume that you know that the neutral and earth grounds have to be kept separated for a subpanel so you have to have four wires for a 220V subpanel if you are going to wire any 120 volt circuits off of it. I do/did some automobile painting also so I have a large air compressor. I had planned to use the moisture separator that I use for painting for the plasma cutter but maybe I should add another of these filters just to be safe. I have been planning to add a dessicant drier to my painting air anyway.

 

[pajoube]

Harv,
I took your advice and went to a welding supply store and spent almost 3 hours talking with the manager.
After telling him what I would be doing now and my future needs he walked me through different machines. He then demonstrated each unit and then allowed me to do the same.
We settled on the Hobart 175 as being the best machine for my needs. He then gave me a demonstration of a plasma cutting system by Thermal Dynamics. This is a new machine, Cutmaster 38, that they just got in. I about fell over with the possibilities for this machine.
My question to you, is there a machine that does both cutting (plasma) and welding (mig)? Looking at price, for the two machines would be $1600. If there is something that is combined it may be cheaper.
The manager did not have anything to offer in regards to a combination unit.
Thanks for the advice of not going with the box stores, the welding store was able to answer my questions regarding differences (box store/welding store), hands on demonstrations, and variety of products and accessories.
PJ

 

[jimgerken]

Hey Pajoube, thanks for the update. What exactly impressed you about the cutmaster 38? I am looking at the same unit. They are asking 1099 for it. What is your dealer asking?

 

[pajoube]

They had a demo cutmaster 38 on site that we used. The price is the same as yours but here is a suggestion.
Pull up www.tollgas.com, they bought a huge number of these machines. They have many stores and also sell via ebay with free shipping (lower 48). Their prices on ebay are lower than in the store.
I was very impressed with this machine considering how it will be used.
PJ