Using the plasma to cut holes in the water table?

[Improvise]

Hi all,
My CNC plasma setup came with a water table that has 4 x individual stainless steel pans that needed to be siliconed and bolted together.
I'm getting to a stage where I need to clean it out and want to make it easier for next time by creating drains in each tray.

I was wondering if it would be possible to lower the torch and use this to cut 30mm circles in each tray of which I can then add drains and ball valves underneath the table?

Is there any reason why I shouldn't do this or would I be better off buying some metal holes saws and drill the holes? If I can use the plasma to create the holes should I leave a small amount of water in the tray to keep the stainless from overheating?

Any advice appreciated. I have attached a couple images of my table.

Cheers!

20220914_130450.jpg

20220914_130514.jpg

[adbuch]

If you can either lower your torch or raise the pans so that you are able to cnc plasma cut the hole, then I see no reason not to do it this way. I would personally want the pans clean and dry, at least in the area you will cut the holes. I don't think you need to worry about warping just cutting a single 30mm dia. hole. I would suggest that you do a test cut in a scrap piece of sheet metal to get your kerf width and actual finished hole size dialed in before cutting into your pans.
David

[TJS]

The question is. How are you attaching the ball valves. Are you welding threaded bungs in there. If so you may have some warping.

[adbuch]

The question is. How are you attaching the ball valves. Are you welding threaded bungs in there. If so you may have some warping.

I had assumed he was adding feed thru fittings with rubber washers to seal it. Like the fittings on the pan of an evaporative cooler. So no welding required. Even if he was welding in bungs, doing so with tig at low heat would minimize warping. A little bit of warping should not affect the functionality of the water pans.
David

[TJS]

I have tigged a lot of stainless and even on "low" heat you still got to get a puddle. It loves to move. I have found the opposite. Use a higher heat and get a puddle going right away(no hanging around) and go go go very fast(almost like alum process). It sounds strange but it does warp less.

[Plasma-art]

Welded alot of stainless steel for the food industry and totaly agree on the high heat.
What I tend to do is try to minimize the gap and without adding filler rod just flow it on high amperage.
That's how I welded the 1 inch air fluidizers fittings on hoppers made from 2.5mm 316 sheet.
Downside it takes practice so for a one off you are probably looking at some more warping.

[Improvise]

Yes I will be using a poly tank outlet fitting that has rubber washers either side to seal it. Plan is to saw the nut off the top to make it more flush. Underneath a PVC ball valve will screw onto the thread of the tank fitting. I will then screw a barb fitting onto this and when I need to drain the table just attach the hose and open the ball valve.

Also wanted to ask your thoughts on washing soda or borax as a substitute for plasma fluid? Plasma fluid here is around $210 for 20 ltrs. Whilst I initially thought this wasn't too bad as I was told I only had to drain the table twice a year, I am finding evaporation loss is huge.

My setup is under a patio so between wind, heat and cutting, my table loses alot of water every week. Every time I top it up with water I am diluting the plasma fluid. The water is turning a rusty colour very quickly (particularly the areas where the water isn't being stirred up by cutting) and when I cut a piece (business still far from being able to cut a whole sheets worth in one go) the water underneath is splashing up underneath the whole sheet and causing it to rust out before I need to use it. I try wiping it down but doesn't seem to work that well. In the mean time I have ordered a car cover to cover the table when not in use to prevent some evaporation.

[adbuch]

I have tigged a lot of stainless and even on "low" heat you still got to get a puddle. It loves to move. I have found the opposite. Use a higher heat and get a puddle going right away(no hanging around) and go go go very fast(almost like alum process). It sounds strange but it does warp less.

I meant as opposed to mig welding.
David

[adbuch]

Yes I will be using a poly tank outlet fitting that has rubber washers either side to seal it. Plan is to saw the nut off the top to make it more flush. Underneath a PVC ball valve will screw onto the thread of the tank fitting. I will then screw a barb fitting onto this and when I need to drain the table just attach the hose and open the ball valve.

Also wanted to ask your thoughts on washing soda or borax as a substitute for plasma fluid? Plasma fluid here is around $210 for 20 ltrs. Whilst I initially thought this wasn't too bad as I was told I only had to drain the table twice a year, I am finding evaporation loss is huge.

My setup is under a patio so between wind, heat and cutting, my table loses alot of water every week. Every time I top it up with water I am diluting the plasma fluid. The water is turning a rusty colour very quickly (particularly the areas where the water isn't being stirred up by cutting) and when I cut a piece (business still far from being able to cut a whole sheets worth in one go) the water underneath is splashing up underneath the whole sheet and causing it to rust out before I need to use it. I try wiping it down but doesn't seem to work that well. In the mean time I have ordered a car cover to cover the table when not in use to prevent some evaporation.

This is exactly what I thought you were probably going to use. So no worries about heat from welding. If you are really worried about warping from plasma cutting, then just use either a hole saw or chassis knock-out punch. Lately I haven't been adding anything to my water. It evaporates so fast that if left unattended for several weeks the pan is almost dry. My pan is 48" x 48" x 4" deep.
David

[TJS]

That washing soda mix creates a lot of while residue everywhere. It was awful. I am using another test tank powder stuff and it also produces white granual junk everywhere. I am going to do a cleanout soon and use the plasma quench stuff. I do not have a bladder to drain my table into but it is in my mind.

[adbuch]

By the way, in the past I have used Hangsterfer's S-500 CF water soluble coolant in my water tray with great results. No white residue or other problems. I already have it since I use it also in my cnc machining centers and horizontal band saw. I was using it more for anti-rust since my water pan is made from 11 ga. cr steel. Since the coolant doesn't evaporate with the water, I don't add it every time I refill the water tray from evaporation.
David

This is what it looked like when I first filled it.

20170807_231037.jpg

[Improvise]

Anyone with any feedback using Borax?

[adbuch]

Anyone with any feedback using Borax?

https://plasmaspider.com/viewtopic.php? ... ma#p211767

borax.jpg

[Improvise]

thanks David! I will try this after I run out of the fluid and report on it.

[adbuch]

thanks David! I will try this after I run out of the fluid and report on it.