On Sat, 2013-09-28 at 23:03 -0600, Gregg Eshelman wrote: > On 9/28/2013 5:16 AM, Erik Friesen wrote: > > For the high speed vacuum, why not just use an external tank, with plumbing > > valve or equivalent to switch to whichever has highest vacuum? > > That's fine if you have the space and funds for a big tank, and a good > vacuum pump. I bought an old but excellent condition Gast rotary vane > vacuum pump, but haven't used it in some years since for the mold making > and casting I do pressure has worked much better. > > Pulling a vacuum in a large tank takes quite a bit of time, unless you > get a very high volume pump - and you'd best have a high volume bank > balance to get one. ;-) > > Instead of one large tank some smaller ones can be ganged together with > a manifold. Propane tanks with the valves removed so they can be hooked > together with as large of pipe as possible will work, but getting the > smelly stuff out can be a problem. I tried it with one tank, with the > insides of the valve removed and opened up some with a drill to reduce > restriction as much as I could. The stink would draw right through the > vacuum pump and smell up the whole shop.
mercaptans are soluble in sodium hydroxide soln; don't know the ideal concentration. Also Clorox should oxidize them but be careful about using on concentrated mercaptans due to rapid reaction rate. Dissolving them in sodium hydroxide and then oxidizing with hydrogen peroxide should work but the commonly available 3% peroxide may be a little wimpy. 30% works better but is hard to get and nasty to handle. YMMV HTH > > To sorta on-topic this, one of the tasks I plan to put my mill to is > making prototypes of things in metal to use as masters for RTV molds to > make plastic castings. > > ------------------------------------------------------------------------------ > October Webinars: Code for Performance > Free Intel webinars can help you accelerate application performance. > Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from > the latest Intel processors and coprocessors. See abstracts and register > > http://pubads.g.doubleclick.net/gampad/clk?id=60133471&iu=/4140/ostg.clktrk > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register > http://pubads.g.doubleclick.net/gampad/clk?id=60133471&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
