Doubt about wiring THC to Plasma Argon PLC65

[sibelius]

Hi
How things are going? Valerio here, new member.

I have lots of problems and I am trying to face one by one.
I will start from this:

I bought my first plasma cutter, very cheap; it is called Plasma Argon PLC 65 Pro and a THC Proma SD, very well!
Now I need to wire the THC to the plasma cutter on the raw arc.
In order to do that I need to add two wires from the minus and plus from the plasma to my THC and what i am looking for is a tidy and safe way to do so without open the plasma.
As you can see from the front of the plasma there are not predisposition to add any wire in the front.
I was thinking to curl the conductors in some way but it seem an unsafe way to do it.
Any suggestion would be appreciated.
Thanks.
V.

Plasmargon-Air-Plasma-Cutter-PLC-65P-pilot-arc-IGBT-Inverter-DC-CNC-Compitable-Fully-digital-panel.jpg_640x640.jpg

[acourtjester]

You will need to open up the case of the plasma unit to get at the wiring for the THC connections. The plus connection is the work lead (attaches to the metal being cut) minus is the torch connection.
Here is a video showing what the inside look like but no real info, no manuals to download from the web????

[sibelius]

Hi friend, thanks for your answer.
My plasma came in a carton box without instructions but I am not to worry about that.
I am sure I can connect the plasma to the THC opening the plasma box, I m just not so keen to do so but I might have to go this way.
Thanks again for the video and your help.
ciao

[robertspark]

make sure you wire the plasma cutter to the THC the RIGHT way around (polarity).

The clamp is (+) and the torch is (-) with respect to to the clamp.

[Dingo74536]

This video from Proma although about the Myplasm system, the principle is still the same in regard to their other THC's like your SD will explain how and where t connect to the Proma for raw voltage.

[acourtjester]

Sibelius give a reply as to how things go, it helps others who may be using similar setups in the future.

[weldguy]

I'm with these guys, open it up and make your connections. I can see a way to do it without opening it but I certainly wouldn't do it that way. Curious how it works out for you.

[sibelius]

Hi everyone, I apologize for the delay, but I hade some very serious problem and only recently, slowly I can come back.

I attached the schematic of my plasma DIY, you can see others schematics of my two machines and the one that I derive my plasma.
Feel free to ask if something is not clear.
Basically I open my plasma and attached two cables, one to the torch (-) and the other to the plier (+), in my plasma model nothing needs to be soldered, on the site of the torch, after checked the continuity, I insert a new cable and at the end of the added cable I added a big ring and simply put the new ring around the contact.
For the other side I checked the continuity again and I added a new cable with a smallish ring at the end, then unscrew a screw from the pcb and add the new cable, screw back the screw after I put the ring in the middle and voila'.
I need to do this job in order to have an access for the Proma SD raw arc.

The wiring of the Proma Sd is quite straight as you can see from my schematic, also there is the new wiring for the mechanical switch on the 3dprinted floating Z.

I will take some pics of the mach3 settings for my machine so you can have an idea of what i did.
My machine is working, so far I manage to do only one cut but seems that its behave is the right one.

Mach3 update will follow.

Regards
V.

Plasma_floatingZ.dwg

[sibelius]

here some pics of the mach3 config

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[acourtjester]

If it works you did it right, thanks for the update reply. One thing I see from the images is your hand hand torch is not supported to where your hand would go. This allows the cable to flex the torch as it moves around while cutting. On my first plasma table this is how I mounted a hand torch. I also use a cable boom for the Plasma cable I have a attachment on the axis to support the cable from above to reduce the cable movement influence.

new torch holder (7).JPG

new torch holder.JPG

[weldguy]

Great torch mount tip from Tom, I have seen sooooo many flimsy hand torch installs and it will really show in your edge quality guaranteed.

Let us know how it all works out and be sure to get everything cutting well BEFORE you start to use the THC.

Often getting the THC to function well is the hardest thing to accomplish, so you want everything else working well, and have confidence in your basic machine operation before introducing it.

Best of luck and have fun!

[adbuch]

Tom - it appears to me that the torch is supported as to where your hand would go - see attached photo.

sibelius - great job and nice description of your project. We will look forward to seeing some of the project you make with your new cutter setup.

David

new torch holder.JPG

[acourtjester]

Thanks that holder is long gone, since moved on to Hypertherm machine torches on newer tables I built.
Just dug the image up to show how a hand torch should be supported.

[adbuch]

Thanks that holder is long gone, since moved on to Hypertherm machine torches on newer tables I built.
Just dug the image up to show how a hand torch should be supported.

Tom - my mistake. I thought you were showing a photo that the OP had posted somewhere. I didn't see it in this thread, so wondered if it was a screen shot from a video he provided or?? Thanks for clearing that up.

David

[sibelius]

Hello everyone

I like the idea to fix the hand torch, at the moment my floating z is holding the torch only by its neck so the other solution appears to me more stable.
As you notice my floating z is made of 3d printed parts, basically plastic so it does not have much of rigidity and I am planning to remake it in metal. I didn't' do it in metal the first time because I have anxiety and I didn't want to wait.
I have tried to cut into a piece of metal that belong to a computer case so only 0.2 mm or so of thickness.
Do to anxiety I didn't fix properly the piece on the water box that I use underneath, the piece itself bended and despite the correct path followed by the torch I did not manage to cut.
Basically the idea was to cut for holes and the square outside.
I think I went to fast, my current was about 25A ( I suppose more than enough to cut such thickness) and I think I did not have enough air pressure ( I don't remember the figure).
The result was that the 4 holes were cut but not very circular, to much dross, the square around was not cut, just marked.
I will try to cut a 2.2mm thick panel at 30A, 850mm/m feed, 35 psi with 1.5 kerb and 1.5 mm working distance torch-work plane.

Will see what happen.
Regards
V.

[adbuch]

Did your plasma cutter come with a manual with suggested current setting and speeds for manual cutting? I would expect the manual would also state the suggested/required inlet air pressure for successful operation.

David

[sibelius]

No unfortunately no manual, I suppose I was lucky enough to find a plasma inside the box.

[adbuch]

No unfortunately no manual, I suppose I was lucky enough to find a plasma inside the box.

Then just do some test cuts to find the values that work best for your particular situation.

To give you some reference, here is the cut chart for Hypertherm 45xp, 65, 85, etc. with Duramax torch.

David

ht 1.jpg

[sibelius]

Very good, thanks so much

[sibelius]

Hi all

60psi at 45A at about 900mm/m.

Result: The plasma drop didn't go through the 2.2mm metal sheet.

I think the solution could be:
1- slow down the feed rate
2-increase the amperage
3-increase the psi (impossible I have a very cheap compressor)

I need to build my floating z out of metal, the PLA is way to flexible.
Any advice welcome

Thanks
V.

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20230717_165814.jpg

[acourtjester]

One thing you did not list is the nozzle size, if you are using a 1.0 or 1.1 nozzle it may be to big for 45 amps. This will cause the plasma stream not to have the power to cut through. I would also boast the air pressure, if the compressor is not good enough you will not get good cutting from the setup. It seems the speed and amps are ok for that thickness of steel. You did not list your cut height which should be about 1.5 MM.
There are many 3-D printed torch holders being used on other CNC tables, maybe a different design, show images of yours.

[sibelius]

Hello,
regarding the size of the nozzle, I don't know, I am pretty sure that is not indicated, anyway I need to order more consumable so any suggestion on size would be good considering that my main goal is to cut metal up to 3mm thickness.
Cut height was 1.5mm.
Looking at my gecko actually I can see that the cut went through on some parts of the perimeter and this was enough for me to detach it from the sheet with a bit of work.
Regarding the air, I am stuck; my baby compressor load 110psi in about 85 seconds and when my cut start, after 12 seconds it start again to load air but the pressure does not goes lower than 60psi and that is my limit.
From the photo you can see, I hope, the kind of floating Z that I 3d printed. I am going to make it out of metal for better rigidity.

Thanks for your help
V.

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VID-20230717-WA0000_Moment.jpg

[sibelius]

I forgot to mention that I have some problem fixing the cut height so in this cutting it meant to be 1.5 but I estimate that was much less because I reckon was touching in some points of the sheet despite the fact that the sheet was fairly level.
I did not use my sensor promaSD, it was off also because I didn't test it properly.
I think the problem could be in the figure that I put in the post processor that represent the distance that the floating z need to travel from the sheet surface (when the tip of the torch barely touch the metal sheet surface) to engage the mechanical end switch that activate the trigger of the plasma.
I need to investigate more this part.

All the best
V.

[adbuch]

My first thought when I saw you photo of failure to cut thru was that this is typical when the cut height it too high (torch too far away from material when cutting). What is the recommended air pressure for your plasma cutter? That compressor seems awfully small with a small storage tank as well. Perhaps that is what you are stuck with for now due to lack of funds or space limitations. I like Tom's idea that perhaps you are using the wrong consumables. Does your plasma cutter have mechanized cut charts showing cut height, speed, current setting, as well as recommended consumables for particular material thicknesses? But at least you got it cut and were able to break it out of the sheet of material, so that's a start.

If you've got flat material and the cutting grates are parallel with the x-y plane of motion for the torch, then you should be able to cut with your thc turned off and set your cut height manually. I would consider doing that until you get all the other variables dialed in.

David

[sibelius]

No manual or instructions at all for my plasma.
The compressor is very small, 24L storage and his max load is 110psi that drop to about 60 psi in about 10 s but it keep this pressure all the way long.
I will check my consumable and maybe try smaller size once I figure out the size of mine.
I would say that material in the range of 2 to 3 mm is fairly level so no need for the sensor and for the floating z as well.
I will have a go with more experiment as soon I can use my toy and I don't have to work.

Thanks in advance