On Sun, Nov 3, 2013, at 02:31 PM, Gene Heskett wrote: > On Sunday 03 November 2013 13:56:49 John Kasunich did opine: > > > > You really need to get familiar with the McMaster Carr website. They > > tend to sell decent quality stuff, and even if you are so far back in > > the woods that they have to ship in sunshine, I'm sure UPS will > > deliver. (In fact, UPS probably brings in the sunshine.) McMaster > > ships from Aurora Oh, so it is probably only 2 days from you. > > While I have bought some stuff from McMaster Carr, its more because they > may be the only ones stocking what I need. Either way their prices are > astoundingly high. Take a nook bronze nut for 1/2" 10 tpi ACME thread, > with a 3/4" OD, 11 tpi thread (IIRC) on the outside, so you can use two and > adjust easily for very low backlash. 8 or 9 years ago when I bought them > and a stick of black oxide coated, 1/2 10 tpi acme rod, those 3 pieces were > just south of $175. And UPS bent the bolt, about 1/8" in its length. I > straightened it as best I could and used it. I should have bought a > Chinese ball screw for about that money. A longer one for the lathe was > only $138 delivered to my front deck this past summer.
This discussion was originally about taps, and you not being able to get what you need from the local hardware store. Good luck getting acme threaded rod or nuts there. Yes, the acme nuts from McMaster aren't cheap. For that, you find someone who specialized in Acme nuts (or get ballscrews from ebay). > They may have it, but their search engine sucks, worst in the business > and if you do manage to find it, they are 2x to 4x too proud of it in the > $/item column. I just went there, typed in "taps". Got me four pictures, "taps", "tap cabinets", "tap holders", and "helical insert taps". Clicked on taps, got a sidebar with a list of thread sizes end such. Clicked on 8-32, got a list of types. Clicked on spiral point, and got a full page of taps, ranging from high-speed steel in black oxide or bright for $6.20 each, coated taps for hardened steel up to C40 for $8.82, high performance vanadium steel with various coatings from $11 to $22 (the $22 one is designed for production tapping in hardened steel), cobalt steel for $8.17, and at the gold plated end of the scale, solid carbide for $102. Clicking on spiral flute instead of spiral point gets you a similar selection. Spiral flute works better in blind holes, but I prefer spiral point whenever I can possibly design for a thru hole. I've used their plain old HSS taps (the $6.20 ones) and have had great results. I don't know what you consider too expensive for a tap, but I'm satisfied. -- John Kasunich [email protected] ------------------------------------------------------------------------------ Android is increasing in popularity, but the open development platform that developers love is also attractive to malware creators. Download this white paper to learn more about secure code signing practices that can help keep Android apps secure. http://pubads.g.doubleclick.net/gampad/clk?id=65839951&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
