Yes, HTDs are cogged tooth pulleys. They are similar to timing belt pulleys except the teeth are rounded.
GT2 belt pulleys are HTD like but they are a newer, improved design. Dave On 5/1/2015 11:44 AM, Gene Heskett wrote: > 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 --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com ------------------------------------------------------------------------------ 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
