Last Updated: 05-
Plasma Water Tables can present a challenge when it comes to finding the ideal additive for the water.
We are constantly looking for the ideal additive. One day when we were cleaning some parts with Evapo-
Here is a brief breakdown of what Rust-
PROTECTS FROM RUST FOR UP TO 6 MONTHS
SAFE ON SKIN
NO FOUL ODORS OR STRONG FUMES
SAFE FOR ALL TYPES OF METAL
SAFE ON PAINTED SURFACES
We used a product Called GreenCut for the first year of table use. After that we cleaned out the table and tried Plain water with no additives for one month and will never do that again. The rust that resulted was horrible. The slats were the main victim but the splash onto the sheets being cut caused staining and very rapid rust production. Here are some pictures of the resulting rust.
To get the table ready for the Rust-
With the table clean it was time to mix up the Rust-
This picture shows our mini lab that we set up for initial testing. The refractometer is the object in the lower left. We used distilled water to calibrate the meter before the first use. The cut has the Rust-
PH paper is not exact but it will give you an idea of where you are at. We first tested our water and found it to have a ph of 6-
To ensure that the concentration was correct and the Rust-
There is a slight odor to the mix but nothing overpowering. Our table took a total of 80 gallons to fill. We used all 3 gallons of the concentrate to achieve our 4% mix solution.
Ok if you are doing your math here: 70 gallons = 14 (5 gallon buckets) 28 oz per 5 gallon bucket = 392 oz total, but 3 gallons = 384 oz so somewhere there are a few ounces more or less. This gets you in the ballpark for mixing and achieving the correct ratio though.
During the mixing process I got the mix on my hands, arms, legs, ect, no burning or irritation was ever felt. While its never a good idea to expose your unprotected skin to any chemical I did not experience any reaction to the Rust Block.
With the mix complete and everything added to the table you can see that the amber tint is no longer visible. The bubbles are from some over mixing / aeration on my part.
There are many options available when it comes to additives for your water table. From commercially available additives to home brews that you can find on the forums and web. Most of the commercially available options have MSDS sheets with so many warnings and dangers that you feel like you need a hazmat suit to use them. There are several debates about the cancer causing potential of some of the commercial options as well as the home brew options that you find in the forums.
The reality is that what ever you use will get on your skin and will be atomized and vaporized during the course of cutting so its imperative that you pick a safe option. Rust-
Concentration checks with evaporation
Affects on painted and powder coated surfaces
Affects on plasma cut performance
Check for settling of product
Checks for affects on aluminum and stainless steel
We would like to get a minimum of a year out of this mix. We will update our observations of the next few months to keep you updated.
*(Test Start Date: 8-
For more information on Rust-
How Do we expect it to work?
The idea with using Rust-
What about welding, painting and powder coating of the metal after having this film deposited? The film is water based and can be simply rinsed off with fresh water.
We send a lot of our products out for paint and powder and will test this out.
Test update: 12-
We have been using the Rust Block in our table for a few months now and have had mixed results.
Advantages: No change in cut quality, no problems with damage to the power coat finish in the tank, no problems with finishes ie painting, powder coating, anodizing or metal stains and patinas. No interaction problems with metals tested: aluminum, stainless steel and aluminum. No increase in smoke or fumes* (non scientific testing visual comparison only) We have also had no problems with skin irritation from contact with the liquid. Also no eye or lung irritation has been noted during the test. We did not find any settling of the product over the course of the test. We found concentrations stayed even throughout the solution. We also were very pleased to find that while we had significant evaporation during the test it seemed to only be water loss as when we refilled the table, and tested our concentration we were still at a 4% concentration.
Disadvantages noted: The rust blocking abilities had been under what is expected or have found with the GreenCut test. We saw no change in rust on the slat surface covered by the solution. When the solution level lowered we saw increased rust formation on the tops of the slats after extended air exposure. We did tests with the material scrap left from a cut and placed some on the back corner of the table over the bed and some we stored with our other scrap steel looking for rust formation. We noted significant rust formation on the pieces left on the table. Those pieces that were stored indoors in our metal scrap pile showed minimal rust but still we had rust propagation across the service after being exposed to the Rust Block solution.
We also noted an increase in our PH of the solution up to a 12 during the course of the test.
We contacted the manufacture and informed them of the test results and requested a second pale of the concentrate to increase our solution concentration to 8% and retest.
We received the second pail of concentrate same as the first and added it to our table. This mix brought our concentration to 8% as measured on our refractometer.
We tested our PH and found after adding the concentrate and filling the table we were at an 11 which is close to baking soda and a household ammonia solution.
For the second phase in this testing we plasma cut several circles out of 20 Gauge mild steel. The circles were all sandblasted on both sides and dipped into our new solution. The circles were placed in several locations: Fully submerged in the tank, sitting on top of the slats and placed in a few places around the shop. We will evaluate the samples and the solution over the next couple of months and update the information.
The photo above shows the rust/crystaline formation on the top portion of the slats that had formed during the first few months of testing.