Plasma Table Fluid

[gorillamotors]

How often or how do you tell when you need to change out the fluid in your plasma table tanks?

[spoolnms]

I am new to cnc plasma, and only cut about 4 4x4 sheets so far. But I would imagine when it starts to get full of debree?

[DezertBlingMoto]

Are you referring to the metal scrap that falls in table or the actual liquid itself ( plasma quench ) for the droppings , I just bought a magnet from harbor freight and go fishing every other time I cut metal .

[The-Meerkat]

I drain and refill it just often enough to avoid brewing any nasty stew in it. Once a month or so. I saw a short video awhile back on YouTube where a guy uses Borax. I add a half box of Borax (as in your mom’s 20 Mule Team Borax she added to the washing machine) to fresh water. It’s a lot cheaper than the water table additive. Works great.

[harrymorley]

sodium nitrite powder. Its available on Amazon and also at any spice store that sells spices for sausage, jerky, etc. Google sodium nitrite as an anti rust additive. right now I just drain mine on a regular basis.

[BrooklynBravest]

I found “Johnson test tank powder”

Which turns the water green like greencut and is extremely concentrated. One bag will do 300 gallons.

It’s $30 for a 3 pack shipped so enough for 900 gallons.

The only concern is it is sodium carbonate which is very slightly toxic and this is an extremely diluted solution as well. I highly doubt it being worse than plasma fumes/dust regardless.

[djreiswig]

You can get sodium carbonate in the form of washing soda at any grocery store. It's not green, but it serves the same purpose and it's a lot cheaper. Many of us have good luck with it.

[TJS]

Brooklyn,
Does the “Johnson test tank powder" have that white powered fuzz all over the place after a while like the washing soda does. Also where do you get the “Johnson test tank powder"

[The-Meerkat]

TJS,
I Googled it. It’s sold on Amazon. $29 for a 3 pack. Free shipping. It’s also available on EBay. I’m curious and might buy some to try too.

[TJS]

Just an update with this stuff. Been using it for a while. It produces the white residue stuff really bad. I do not advise using this stuff.

[weldguy]

Just an update with this stuff. Been using it for a while. It produces the white residue stuff really bad. I do not advise using this stuff.

[adbuch]

I use Hangstefers S500 CF and have never drained my water tray in the 5 years I have been using it. I get a lot of evaporation, so I normally only add water or water/coolant mix to keep the level above the catch screen. I am a hobby guy, so I am only actually cutting maybe several time a month.
David

This is what it looked like when the table was new. I suppose I should take a picture to show what it looks like now.

20170807_231037.jpg

[jimcolt]

My recommendation is to not put anything that was not specifically designed to be used in a plasma cutting fume control table (water table). The plasma is a high temperature electrically charged arc that emits a fair amount of ultraviolet light. These features can change the makeup of certain chemicals creating potentially dangerous fumes. Only use pure water or water with additives that were designed / approved by a company that has fully engineered the product for this use. I used water tables (with pure water) for 25 or more years in a variety of plasma cutting tables....the water worked great as long as the table was cleaned regularly, and the water strained and re-used. Using additives suggested online from non-chemical engineering experts could shorten your life, or at least affect your health. Jim Colt (PS, my two cutting tables use downdraft fume controls, no water. I get great consumable life, great cut quality and no smoke in my small shop)

[weldguy]

I too am a fan of the downdraft system over water tables. Works like a charm with the only issue being heat loss in the winter.

[adbuch]

This is the same table as I showed in the previous photo. I failed to mention in my comment above that this system also incorporates a draft system with exhaust fan. The water tray sits about 11 inches below the bottom of the cutting grates, and the draft system is designed to extract any smoke/fumes to the outside of the building. At this point I am normally adding pure tap water to the water tray to make up for evaporation. Once in a while I add a small amount of the S-500, purely as a rust inhibitor as the water tray is made from 11 ga. cr steel.

David

20170812_210027.jpg

[adbuch]

Jim - I appreciate all the help you have provided over the years. You were the one that confirmed that I has the "sewing machine effect" early on when I was setting up my Plasmacam. I had the work clamp cable coiled up under the machine, resulting in a large inductor effect that affected the arc voltage.

I purchased my Plasmacam as a result of watching some Youtube videos from Keith Fenner. I basically emulated his water tray/draft system build. At the time, the cost for the stainless steel to build the water tray was around $350 as opposed to under $100 for the steel - which I already had. So I opted for the water tray constructed from 11 ga hr steel. I initially added the Hangsterfers S-500 to the water as I felt that this might give me some protection from rust thru on the water tray.

After 7 years in service the water tray is still intact. As I mentioned above, I currently add only fresh tap water to the water tray. My theory is that the water soluble coolant doesn't evaporate with the water, so some residual coolant may still offer me some protection from rust. Had I opted for the stainless steel water tray, then I would have used straight tap water without any additives. Here in Arizona, the water evaporates so fast that there is not much time for mold or other contaminants to develop.

In case you or any of the other members are interested, here is the documentation of my water tray/draft system build.

https://photos.app.goo.gl/h8LHufi6frttfGNQA

As always, I appreciate your efforts to keep us informed with regard to the cnc plasma cutting knowledge base.

David

[jimcolt]

Great setup! You have what I call a Hybrid water/downdraft fume control....and it is the best setup for controlling fumes. The water is low enough so it does not splash on the workpiece or moving parts of the machine....and the water tends to trap all of the larger particles of molten metal, while the downdraft handles the fine particles that are lighter than air and tend to rise. I built a few demo tables for Hypertherm that get used at trade shows (about 8 years ago). Nice setup!

[adbuch]

Thanks Jim! I'm pretty sure I remember seeing your setup. I seem to remember that is was for the SEMA show. I also remember a demo you had showing using he 45xp for "engraving". I'll have to revisit that one. I do have a 45XP, in addition to my PM85. These days I am using the 45xp mainly for cutting tubes on my Plasmacam rotary tube/pipe cutter.

Here are some photos of my stand-alone Plasmacam pipe cutter when I first set it up.

https://photos.app.goo.gl/wGY4tTBqc8FAd8ee8

The idea was to mimic the normal Plasmacam setup while eliminating the need to move the gantry every time I wanted to use it.

I did post a few videos on Youtube. Here is one of them.

https://www.youtube.com/watch?v=72xrrYbOROs

Thanks for you response.

David

[Creative25]

On my new table I just use water. I painted the tray with roof sealer. I just wonder if there is no additives in the water, once I drain it can I use the water to water my garden? Trees etc?

[adbuch]

On my new table I just use water. I painted the tray with roof sealer. I just wonder if there is no additives in the water, once I drain it can I use the water to water my garden? Trees etc?

I don't see why not. I don't think it would be much different than water bleed off from an evap. cooler, which I run onto one of my trees.

David