August 17, 2004

In This Issue of The Acid Staining Newsletter

Oranges Peelings to the Rescue

In the last newsletter I touted the ability of Ultrite Degreaser to remove liquid curing compound from a slab in order to make it stainable. I must have been tempting Fate. The very next week my crew encountered a slab which we were scheduled to stain, but it had curing compound all over it. We had no Ultrite Degreaser on hand, and no time to order it. We turned to our next favorite cure-all - a strong citrus cleaner called De-Zov-All, made by Harvard Chemical Research, Inc.

We purchase De-Zov-All in five-gallon buckets at a janitorial supply store which carries Harvard products. We have formerly used it with good effect to remove black mastic from slabs—probably the messiest, gooiest thing you will ever have to deal with. After discovering that it melted the tarry mastic, if applied full strength and given 40 minutes to work, we began to use it on floors with paint spots, glue and other contaminants. We found that for these things it was best to dilute it one-to-one with water (it will turn cloudy right away), soak the floor with the diluted mixture and keep it wet for 40 minutes, then scrub with a buffer fitted with a black pad.

Keeping our fingers crossed, we used diluted De-Zov-All on our curing compound floor and found that it worked fairly well. It did not get all the way through the compound on the first try, but one or two more soaks and scrubs did the trick. In a day and a half the crew was able to clean 1050 square feet of curing compound. This includes a final scrubbing with TSP solution. You must use TriSodium Phosphate afterwards, since the citrus cleaner itself tends to throw off the stain. TSP cuts through it and makes the slab perfect for staining.

I spoke with Harvard Research’s technical representative who told me that they make an even stronger version of citrus cleaner called, Conquer, which is sold in quarts, gallons or 5-gallon containers. I could not find Conquer listed on their website. If you want to order it, you might need to phone the company directly at: 1-800-423-7514.

The “active ingredient” in these products is called d’limone and Conquer is 100% d’limone. The peels of oranges are squeezed—in Florida or Brazil , and the biodegradable extract harvested is a natural solvent which is not acidic. Believe me, the pleasant citrus odor is worlds better than methylene chloride (the active ingredient in paint strippers) and it is nice for your workers to know that it is a non-toxic, biodegradable product.

There are probably other good brands of citrus cleaner on the market, but I would advise against getting them at home improvement or paint stores. They sell some diluted versions (tinted orange to make them look stronger), which do not remove anything, as far as we can tell. The real citrus cleaners are fairly clear in color until they are mixed with water.

Just before this Newsletter went to press, I got a letter from Keith Miller, a technical rep at Unitex chemicals ( They make a cleaner called Citri-clean which also removes curing compounds. Unitex is in the business of manufacturing curing compounds and has developed one which allows more moisture loss from the slab than past compounds, and which may therefore allow penetration by acid stains. It has been tested by Chris Sullivan at QC Construction products.

This photo is an overall view of plastic
patterns and color

The problem for Unitex is that there is an old ASTM criteria (number C309), written before acid staining was so popular, which requires that moisture loss through a curing compound must be less than .55 kg/sq.M. The moisture loss through Unitex’ compound is close, but it is .67 kg/sq.M. They are test marketing on the west coast, and working to get the ASTM standard loosened up a bit for the benefit of acid stainers everywhere

Our “problem” floor turned out to be one of the prettiest stain jobs we have ever done. See photos. We used primarily Scofield’s Weathered Bronze stain, but poured blue into it, mixing on the floor. We laid thin plastic into the stain on the first staining, then restained the floor with Weathered Bronze and blue a second time with NO plastic. This made our plastic patterns recede and look mysteriously subtle.

This gives a close-up of lighter speckle marks
which often occur even after most of
the curing compound is removed

Happy Staining!


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