On Friday 01 May 2015 06:25:03 Les Newell wrote: > I just ran the numbers and for the dimensions you gave the belt length > is almost exactly 375mm. For those sizes I'd use a HTD toothed belt. > Pulleys are fairly cheap and belts are easily available in wide range > of sizes.
Well, the smaller of the two pulley sizes is subject to leaving enough room for the taper-locks locking and jacking screws, which I intend to install from the larger pulley side. The smaller pulley won't even be cut until the taper-lock hub is made, and a stub shaft made that is the same size as the spindle shaft, and the whole assembly is spinning on that dummy shaft. Depending on available material for the bolt circle, the small one could be even smaller than 40mm. 35mm would give a 1/2 down, or a 1/2 up. It remains to be determined if the bearings can go to 10k rpms. I can see the thermal growth of something during a long session of pcb etching, its so obvious I break into the code stream a couple times in a long run and rezero the z at copper contact. The HTD is a cogged timing belt? Yes. That probably takes the $ up by 10x as I cannot do a cogged pulley that accurately & would have to buy them. And one thing noticeable absent in any of the pulley listings is two sizes for a speed changer on one pulley. I can cut the polygrove/micro-v stuff right here for nothing but my time. One page even claimed it could run above 500 rpms, but I'll be doing 20x that as long as the bearings don't explode. > It is a pity your belt is so short. Automotive poly-V belts are > available in roughly 5mm increments from 600mm upwards, widths from 3 > to 8 ribs. Just for reference the part numbers for PK series poly-V > belts are easy to work out. For instance a 3PK0750 belt would be 3 > rib, 750mm pitch circumference (cut length). So as projected, I would need a 3PK0375. Sounds about right. I came to that same conclusion. Too bad this isn't my GMC pickup, but that belt is also 50x the material and north of $50/copy, where this stuff is piddly. :( Thanks Les. How is your headboard carver doing these days? Now, I'd better go see if there are any fat caps in that box. And get a part # for it if not. Something has to be going doofy. That would give me a good excuse to exersize my new soldering station. The iron quit in tha 18 month old one and the outfit in star city Nebraska won't sell me another control board. 1 year warranty. Ass holes, the whole lot of them. But I got one just as capable from Amazon for 1/2 the bucks. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users