Metal Shop Hand Plasma status

Fresh in the mail, we are happy to announce we have a hand torch for the new plasma generator!

What does this mean? We have a fancy Thermal Dynamics Cutmaster 120A (courtesy of @Laserfixer ) that will be available for use soon, in all the 80 Amps of capacity we can offer.

Wait, 80A? That’s a 120 Amp unit!

That’s right. Until we run the 480v (or 100 Amps of 208) we’re not going to be able to run it at full capacity. However, it will be a large improvement over the previous unit (and also hopefully more often in service)

How can I help?

Power

First, we need to wire the power. @TBJK, @procterc, and I talked about it last night and we think hard wiring it is the best way to go. However there is only one 3 phase service in the room that has enough of the angry pixies that make electrons go to make efficient use, and unfortunately that shares the induction forge outlet.

Luckily, the hand plasma is not the most heavily used item in the shop so, similar to the oven, we believe this is workable between @Team_Metal_Shop and @Team_Blacksmithing

Since we’re hard wiring the unit, rather than making an oversized circuit plug, we’re putting in conduit and a disconnect.

We’re additionally putting breakers on the plasma side if we can, at a slightly lower amperage than the main breakers for the circuit (45A versus 50A). This way if someone cranks the unit up and trips a breaker you do not need access to the electrical room to reset the breakers for the induction forge.

Power Parts

Based on a cursory look, the following transfer switch seems appropriate (we have an extra nema box lying around in that room). Someone correct me if anything isn’t right or has a better idea

Alternatively one of these though they’re pricier: https://www.platt.com/platt-electric-supply/Double-Throw-Non-Fused-600-Volt-3-Pole/Eaton/DT362UGK/product.aspx?zpid=80784
(yes, I know they make fusible ones… double the cost and class H fuses rather than breakers, so I’m considering if it’s better to use a local load panel with a 45A breaker.

Jigs

Hand plasmas are valuable for things like pipe, tube, and creative hand use when you don’t have a CAD design to match. Some JIGs like rollers for pipe are useful and any volunteer can weld some up (though if you need more than the steel or parts on hand let me know what the materials are to budget them / order them). Remember if it’s for a committee need, you may use from the DMS metal stock at the front of the room within reason.

Training

The previous plasma was a spot train for those with existing CNC plasma training, and I’d like to either keep that or do a Video training. If someone has a proposal for a Video / Moodle course please reach out to the metal shop committee. If we don’t go the self-train route, I will need volunteers to do the spot train. To get you able to teach it would be relatively easy for prior plasma use (to use it safely that is). I usually did the spot trains for the hand plasma in 5-10 minutes on the old machine and I expect this will be similar.

Signage

I still need someone to give me a refresher on the CNC Vinyl cutter, but until that happens we’ll need signage to be made by a volunteer comfortable with the machine.

  • “Only Energize One Disconnect at a Time” (this will go over near the 3 phase plug next to the disconnects).
  • "Do NOT exceed XXX Amps on Hand Plasma: (this will be on wall above plasma when we determine the final amperage limit)
  • “Training Required” labels to put on the machine itself (and if at it already a few extras; I’ve found some have since come off the other equipment over time so a handful would be nice)
  • QR Code on Power - we can have it point to a video explaining the power as a reminder for those who may forget, or not know about the changes. Explains that the outlet only has to be de-energized when the second plasma is in use, and not required to be done for the CNC table or forge.
3 Likes

Please don’t do the electrical work yet.

We have an electrician coming in to handle some work on the woodshop and will have him do the work.

Thanks James

We’re not in a rush, but to be clear there is nothing happening that’s not on just the local outlet itself.

However, if they’re going to be wiring the metal shop’s 480v transformer whilst doing everything else then it’s moot anyway since that won’t require outlet sharing. However the metal shop committee has heard nothing about the progress on that.

1 Like

When is the electrician scheduled.?
Can he put the 480V 3 phase through the demising wall as specified in the expansion plan?

Yes please!

Metal is no longer going off the 480 that was run in the 102 side (at least last I was told, going on a year now) and instead the old 480 transformer from that side is being installed in the 104 side so it does not have to penetrate the wall.

If there are any changes to that I haven’t been told

Why then was the transformer wired up where it now is? Are we going to undo the work we just paid for, move the transformer and pay to have it rewired? Recently a member said they had a transformer to donate, and Rich said that it would be too costly to install.
Is anyone in charge?

I don’t know I’d go that far, but it seems a bit silly we (the metal shop) have secured donations of transformers, volunteered time to work on the 480V drops, architected multiple solutions to the issue, and still don’t have power a couple years later.

Do you know where Rich’s drawings are, the one’s approved by the city.

That 480v line (which has a new transformer) was basically hijacked for the HVAC on that side. The old transformer is being moved to the 104 side for metal and will come off those panels.

The larger capacity transformer that was up for donation was large enough that code would have required it get its own room, which was not going to be reasonably accommodated.

Could you include the size that the lettering needs to be (or dimensions it needs to stay within?)

1 Like

Sorry for the lack of updates on the electrical. I will try to get it all aligned next week and let you know the status.

1 Like

Since the electrical may happen most of it is on hold, but I’ve got a few that still need to be done. I’ll drop you a DM sidebar with more specifics.