Just wanted to update this.
I did get the 2 fiberglass vessels. Turns out they are about 5/16" thick polyethylene with about 3/16" spiral fiberglass outer jacket. I sawed the tops off, and using about 65 gallons, and 3kw heaters, I get the caustic and phosphate solutions to ~190 f. I washed the parts in a solvent bath to get most of the oils off, then a 10-15 minute caustic bath, then rinse....into the phosphate they go. Small parts don't chill the solution and come out in about 10 minutes. Larger parts that have been soaking in the caustic are still pretty warm (can't handle them barehanded) and don't need much time to reach reaction temperature either. Experimenting a little some parts are pretty fast, some take 30 minutes to develop a proper coating. A quick spray rinse between the caustic and the phosphate bath seems to get enough of the caustic off the parts. Same deal with the after phosphate bath, except it would be better to rinse in a hot tank. Once the part has been cooled off by a water hose rinse, it dries slowly, and the potential for rust is there. So far, I have rinsed with a spray hose, then blown with an air compressor (leaf blower next time), and finally a WD40 spray to stop the reaction and displace any water remaining. Made delivery today of 3 sets of parts for the coil tubing tool, and the customer was very pleased. Once this prototype passes muster, I will be sole manufacturer of this tool. it has the potential for maybe 100 tools a month. Good and bad.....it's more than I can make manually. So, I can sub out some to other small shops I know of around here who run CNC, or go CNC myself. But that still only leaves me.......but I might have to hire my wife and daughter.
Just thought you guys might want to know how it worked out. I failed to get some pictures of the finished parts (I did get some of the pre-phosphate parts). Even though my NDA prevents me from showing too much, I might get away with showing a couple of parts.
