2012/5/12 andy pugh <bodge...@gmail.com>: > > http://www.arceurotrade.co.uk/Catalogue/Collets/ER-Collets-Collet-Chucks/ER20-Collets-Collet-Chucks
Thanks for the link, I had not found this one! > Do you want an actual hob (spiral, needs the right machine, or EMC2 > being clever) or a single-tooth profile cutter? Ok, I think this is the point, where I explain some more details: In school I have a study project - calculate and design some reducer unit. I chose harmonic wave reducer. I am now in process of calculating the gears, especially the flexible gear - wall thickness and exact sizes of teeth - internal, external and pitch diameters with all the corrections etc. I really would like to actually build some. I even found a potential supplier of flexible ball bearing for the wave generator: http://www.kinex.sk/english/?page=katalog_6a&p=1 Although they are not very responsive telling the price and minimum quantity of order for their LGVZ12090 bearings. I do not intend to try to create the gears by myself (at least not yet). There are special gear making machines at school. Old, but advanced enough to be able to manufacture hypoid gears. And the cost would be very low - I already inquired :) The problem is that they do not have the tools for 0,5 module, smallest they have is 0,7. But with ~124 mm pitch diameter the tooth count changes from 247 to 177, which significantly reduces the reduction ratio - from 123,5:1 to 88,5 (bigger is better; welding robot had total reduction ratio of 640:1 in shoulder and elbow joints). So now I am looking for potential sources for tools - I think that I could talk that professor into accepting the tools as a part of payment for the service. I probably should mention that material for the flexible gear (the one with external teeth) is spring steel. > http://www.arceurotrade.co.uk/Catalogue/Cutting-Tools/Gear-Hobs/HSS-Fine-Pitch-Gear-Hobs--Module-Sizes/HSS-Fine-Pitch-Gear-Hobs-05-Mod---25x15x8mm-20deg > is a hob but needs a setup like: http://youtu.be/ZhICrb0Tbn4 In fact, > that is where I bought the hob from. Hmm, no picture... The one You have on Your machine in video is the type the professor showed in school, not those disk involute gear cutters from RDG Tool page. Do I understand correctly what these numbers 25x15x8mm mean? 25mm - length of hob 15mm - outer diameter 8mm - inner diameter Or am I missing something? > For cutting internal gears, I have no idea. That seems to be even more > specialised. Internal gears are created with this approach: http://www.youtube.com/watch?v=adRlGffXM5k I would appreciate a hint for correct word to describe it :) Direct translation from Latvian would be "hewing" The tool looks similar to this: http://hrbtool.en.alibaba.com/product/298684939-210056049/Taper_shank_straight_tooth_gear_shaper_cutter.html > You can buy them, which might be cheaper: > http://www.hpcgears.com/products/internal_gears.htm I am sure that for my totally custom size (not only number of teeth, but also amount of correction) it will be cheaper to buy a tool (I expect it to be less than 40 EUR) and produce it in school (professor said - labor cost is around 20 EUR for one gear) rather than order there. Ok, for one piece maybe not, but for 3 or 4 pieces definitely. > I can consolidate a UK order, then ship on to LV. Thanks! Hmm, that would involve me in yet another risky shipment of beers to UK :) Viesturs ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
