VOTE: Plasma Cutter

My work has an old, but functional plasma cutter they are looking to get rid of.

It is an L-Tec Plasmarc PCM-70, Single Phase model that can operate off of 208/230/460V AC (54 amps @ 208v, 48 Amps @ 230v). Can be used with either air or gas mixtures.

the manual can be found here:

http://www.esabna.com/eu/literature/plasma%20equipment/cutting%20packages%20-%20systems/manual%20(only)%20cutting%20packages/domestic/pcm-70_plasma_arc_cutting_package_f-14-376-b.pdf

looks like they sell used from $400-700 depending on condition, they want $480 for this one.

circuit breaker, plug and wire to have a dedicated 60-amp circuit for it would likely be ~$250-300 depending largely on the length of the cable run. so including that cost, I propose the vote be for $800.

Thanks,

Kevin

Is it three-phase or single-phase?

Single Phase.

I vote yes. We have a spare 60A breaker already, so there’s that.

Oh, and we have a piece of 3/4" flex conduit already, and probably the fittings. I’ll take stock. I would assume that we’d put it in the dirty room, and probably attach a NEMA 14-50 plug to it (which we already have a pigtail for).

The manual says it uses a drag type tip which is definitely the kind we want at the hive.

very definitely vote yes.

Greg,

wouldn’t it be more appropriate to use NEMA 14-60 for this? I wouldn’t want someone trying to plug it in to a 50 Amp circuit.

Thanks,

Kevin

Yes from me

I am in support. However, I recommend that we consider where a plasma cutter would be used, what additional infrastructure or work surfaces are needed, and what needs to be done to reduce the risk of fire, injury, etc.

I’ve never used a plasma torch, only a oxy-acetelyne cutting torch, however, both can shoot very hot sparks, dust, and pieces of metal onto floor, walls, etc. What do we need in order to have a safe, controlled environment for plasma cutting? Could someone who knows more about this add this into the vote, (ie fire extinguisher, welding curtains / dividers, floor fixes, etc)? Even if I’m over-reacting, it would be best if we committed to any needed contingencies from the get-go. Also, remember that the fire marshal does inspect Hive13 on a regular basis.

Lastly, we had a plasma cutter 4-5 years ago. I’m sure it was not nearly as cool as this one, but it was hardly ever used and broke rather suddenly. How temperamental are these things? Do we need drier shop air, better maintenance, a cutting table?

I’m being a bit of a buzzkill here, but I don’t want to see scenarios in which we get a plasma cutter but can’t use it, or get a plasma cutter and a hefty penalty from the fire marshal.

Lorin

We definitely need dry air, I'd suggest we get a cleaner, dryer, and regulator just for this. It would also be a good idea to have a stock of the consumables so they can be replaced as soon as they are worn.

The "table" we have in the hot room is actually more of a plasma cutting table than a welding table, it should be fine for light use. That said, I have considered putting up for vote the materials required to put down a layer of cement board and tile in the hot room, because having hot work over that wood floor (even with a sheet metal layer over it) scares me. There isn't much that would be more fireproof than a layer of cement and ceramic tile.

One problem with tile is impact resistance. It's pretty easy to shatter with a dropped weight. I like tile but not where heavy stuff is likely to be dropped. We probably don't want to spend the money for porcelain which is the toughest tile but still shatters. Concrete board well grouted is very tough.

We need to assure the hot room conforms with fire code. Google fire code chapter 35 Welding and other hot work. That should be our guide for room prep and fire watch tasking.

Just wanted to clarify this vote is not for tonight’s meeting, though I am sure it will be discussed. Unfortunately I will not be able to attend tonight’s meeting. If someone can post here the key points and questions of any discussion, I would appreciate it.

Thanks,

Kevin

The old plasma cutter I brought in years ago was basically junk back then… so it lasted a lot longer than expected. :wink:

As for where… the dirty room already has a welding table in it and we upgrade the floor to handle it… that parts already done as well.

Bill

We need to recognize what it takes to have a proper Hot Work room.
The fire code is pretty lengthy but the key is that walls and floor need to be 1 hour fire rated.
It means all the way to the top of the 20 foot tall wall needs a layer of 5/8 fire rated dry wall. The floor probably needs two layers (1 inch) of fire rated Durock concrete board.

We should not consider a plasma cutter without the proper preparation of a Hot Work room.
Actually, we need to do it for the MIG and TIG welders we have.

Would someone be willing to take on the project manager for this - doing a little light reading, putting together bill of materials, a few volunteers, and a vote to make some durock & anything else needed happen?

Even though this is not glamorous volunteering, we need someone to do it, other than myself, Brad, Dave V, Ryan, or Greg. With the lounge, the laser renovation, annex move, etc the four of us have more than our quota of project management. Of course, anyone can be enlisted to help, but projects like this only happen if someone leads. Any takers?

Lorin

In light of all of the work to get the metal room ready for a plasma cutter and having given the thought more consideration, I have to change my vote to no.

Even if it may not be usable right away, and with knowing we will have to upgrade our Metalworking (or whatever room we decide to use) to handle I am going to vote yes, this is a good deal and it appears the cutter has a good rating (from what I could research.)

Yeah, either fire rating the welding room better, or putting in an outlet by the back dock would be the safe way to tackle it. If others are with using it on the dock I will stay at a yes vote.

It wouldnt be as volatile as oxy torch setup however it produces endless ignition places even by acciden. If the back dock is not a option. I move to a no for the time being.

The improvements to the hotwork room need to be done for the welding equipment that is currently in there, adding a working plasma cutter would not affect that situation…

Even if this thing sits uninstalled or gets used on the loading dock, it seems like a good deal, and adds important capability to the Hive.

As much as I would like to have a plasma cutter in the HIVE, I have several concerns with this proposal and must vote no.
We need further discussion on the choice of the cutter and agreement to go ahead with a hot room.

It is fair to ask; Why is this 25 to 29 year old machine being sold? My bet is concerns with parts and service cost and availability. While there are replacement torches and consumables the cost of these parts adds up. Service parts for the machine itself appear to be a problem. As in, when it dies. It’s dead. No warranty. Not economically repairable.
It is important to ask how you maintain and fix a machine this old. The original maker was bought out by ESAB.

With this in mind, I want a competitive bid comparison with other plasma cutters. Do we really need 3/4 inch cutting capacity? A 60 amp circuit? Has there not been any improvement in the last 30 years? We need to know the alternatives.

What other plasma cutter could $800 buy? Could an alternative just plug into the circuit where the MIG and TIG welders go?

Next concern. Hot Work Room.

We actually need to set up a hot room because we are welding right now.

Operating a plasma cutter carries considerable risks.
Building a Hot Room with fire walls, certification of operators and fire watch tasking are minimum risk mitigations.

Read the fire code.

You need to check terms and references to find the code requires 1 hour fire rating on Hot Room walls and floors in addition to sprinklers, fire extinguishers and a fire watch.

This means:

  1. Get someone to volunteer to lead the hot room project. (As Lorin suggested, Not me. I will help, but I will not lead this one.) Get general member agreement on the overall plan including a $4000 budget including competitive bids on plasma cutter. Get permission from Garden Street to build a Hot Room. Get fire marshal approval on plans. Review plans with membership and get agreement to execute. This would include commitments of labor on a schedule to get this done. This is more work than the annex move and the lounge build out which are not yet complete.

  2. Prep the room. Clear out EVERYTHING. Remove pipes and wires from walls to clear the way for drywall team. That means all the way to the ceiling. This means temporary movement of the air compressor.
    3)Establish layout for new metal working area for Lathe and other equipment outside of the Hot Room. Relocate Lathe.

  3. Contract with drywallers for installation of 1 hour 5/8" fire rated drywall. Scaffold work required. Anyone of you volunteering to hang drywall 20 ft in the air better bring your A game. My scaffold climbing days are long over. Budget $2000 for Drywall

  4. Install 1" of fire rated Durock Concrete board on floor. (two layers of 1/2" board.) Budget $600

  5. Finish piping and wiring the room. Budget

  6. Set up welders, plasma cutter, welding table, blast cabinet, grinders, chopsaws. Anything that makes fire or sparks goes in the hot room.

  7. Establish process to assure everyone using equipment is certified and observes fire watch procedures. (This actually makes welding and plasma cutting a minimum two person operation)

  8. Train and certify welding and plasma cutter operators.

Have a nice day.