need water table info

[massajamesb]

Starting to design a water table. Questions are:
1. Would I need to do any sort of Ph control, should I build the water tray out of HR steel?
2. How deep should the material be submerged, or should it sit right over the water surface?
3. What would be a reliable and affordable way to keep the water level constant?
Thanks for anyones help on this, wasn't sure about all the particulars.

[mog5858]

just speaking about the water table we have at work for are plazma it just made of regula milld steel. we keep it about 2" or so deep. as for having the material submerged i don't know i would like to try it cus well it would cut the smok way down. the water dose a really good job at that but no smoke is better for the lungs.

[massajamesb]

I was wondering if the fact that you are cutting metal using an electric arc, on a piece of metal either contacting water, or submerged in water, would be considered unsafe. Last time I checked, water and electric arcs are seemingly mortal enemies.

[Torchhead]

The water is ground ; zero volts (assuming the tank is metal and the table is in contact with the plasma workclamp). The water would not become electrified. With the workclamp disconnected there could be a problem but the arc would not establish. You can't cut submerged with the type plasmas we use but you can cut with the back of the material sitting in the water and a light film on the top (light enough that the air from the tip blows it out of the way for the arc).

[massajamesb]

Gotcha. That makes sense now. Duh.
Thanks Tom. Shoulda just emailed you. Wouldve been easier and faster.

[ViperTX]

mog5858....I believe that your plasma machine is using the water trough a a means of collecting the slag and other flying debris....you can't submerge the piece you're cutting......where you submerge a piece when cutting is an EDM machine....and then the electrolyte is not water but some type of oil.

[mog5858]

i sean it on t.v aobut a week ago a plasma cutting a fulley submerge pice. but with is much biggger then are cutter. we just use the water table to kill off the smoke. we cut a alot of AL in are shop.

[jcc3inc]

Sir,

There are cases of complete submersion with the torch tip maybe 1/2 inch under water (with the proper torches), and of having water 1/2 inch below the bottom of the cut. And you should talk with the torch mfg to inquire about alum cutting; seems it generates O2 and H2 in the tank. Don't know if this would be a problem or not!

Regards,
Jack C.

[hotrodkid]

Hello, We are running a CNC Plasma with a water table. Our water level is right under almost touching the back side of the material being cut (varies from 1" under to touching depending on evaporation and when I refill). The tank is 5 inches deep with 3 inch support slats in it. Basically 1" off the bottom of the tank the slats start, 3" slats, and an inch of lip on the tale to keep the water down in the table ( so the water won't be right level with the top).
This is working out great for us and compared to the first couple of times I used it without water --- kills I'd say about 95-98% of the smoke, smell, and sparks it makes. There is a little splash up in the water due to the pressure comming out of the plasma --but the mnfg. says that is not a problem as long as it does not contact the electrical connections.

I am planning on posting some photos soon of the table. We made basically a square shaped U table that holds the machine and all it's workings. Then we made a second table (water table) that rolls into this table and bolts into it becoming one with the other. This way we can unbolt the water table and roll it out for cleaning away from the machine itself. Both tables are on heavy casters as well.
I'll post some photos soon.

Hope I've helped
hot rod kid

[Med-Pac]

Water tables work great for steel, but remember you can't cut alum. with a water table. It creates an explosive combination.

[mog5858]

we cut al with are all the time can u explan y we should not.we have not had any problums for about 2 1/2 years. we all so cus s.s and gavnized too. i know u should not cut gavnized do to it beaing really tockic

[Med-Pac]

I've never had an explosion happen before, but many have told me that watertables on a plasma table are a bad idea. You're the first that I've come across that is doing that. We went with a downdraft table to be on the safe side.