2011/2/2 Erik Christiansen <dva...@internode.on.net>: > On Wed, Feb 02, 2011 at 05:35:14AM -0500, gene heskett wrote: >> On Wednesday, February 02, 2011 05:23:40 am Steve Blackmore did opine: >> >> > Easy enough to make a similar design using htd belts and pulleys. >> >> However, using toothed belts & pulleys, 30/1 to get the torque will be a 2 >> step reduction. And that will likely bulk up too much. > > I've often wondered what a two-step htd belt reduction does to backlash? >
When belts are tightened well, then I think it is good from backlash point of view. The main question, just like Gene pointed, is designing it to be compact, not a large and bulky box. 30:1 ratio might require even more than 2 stages - one would need to combine 6:1 and 5:1 ratios to get it in 2 stages, but that involves very high differences in pulley sizes, so for compact design only very few teeth will be in contact on small pulley. But in the mill head the belt will have to deal all the forces between endmill bit and material, that is why I think that just several teeth in contact between belt and pulley might lead to short lifetime of the belt. Viesturs ------------------------------------------------------------------------------ Special Offer-- Download ArcSight Logger for FREE (a $49 USD value)! Finally, a world-class log management solution at an even better price-free! Download using promo code Free_Logger_4_Dev2Dev. Offer expires February 28th, so secure your free ArcSight Logger TODAY! http://p.sf.net/sfu/arcsight-sfd2d _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
