On 4/21/2016 7:09 AM, Gene Heskett wrote: > On Thursday 21 April 2016 04:04:16 Gregg Eshelman wrote: > >> Belt drive from the stepper? If there's enough metal in the pulley, >> drill and tap three holes into the face then get six flanged rubber >> bushings. Mill out a circle of metal with three holes. Put bushings in >> holes, bolts through bushings. Screw to pulley. Hooray! A damper. :) >> > Chuckle. Sounds workable Gregg, but its only a 17 tooth pulley in quite > close proximity to the 42 toother driving the nut, so figuratively > speaking, no room to swing that cat. Besides its a double shaft motor, > and it does have a spool of 1.75" fender washers with elastomer washers > stacked about 2.25" high on the upper end of the motor shaft. See best > view of it at the sig's link + emc/36.html. But thats not the same > motor, that 252 was pulled and a 432 put in its place later. It shows > the whole new Z drive before it was installed on that toy. Back up to > about 29.html to see it installed. Those dampers work very well, took > the motor stall from about 9 ipm to around 34 ipm if everything is > right. But the psu is only 28 volts, and I have a new 44 volter ready to > go in at the same time as I put a 5i25 into that system. Even with > software stepping, I have carved a boat load of stuff on that little > mill. > > But there is very little insulation in that building, so I only keep > enough wintertime heat in it to keep it above the dew point so its off > limits to this old diabetic for long enough to setup and do a job in > cold weather. I'll also need to round up a 5 volt wall wart to run the > rest of the logic in that mills electronics box when I make the psu > switch as the 28 volter has a 5 volt output its all running on now. > I probably have a suitable one of those as I never throw out the wall > warts even if the rest of the kit has died & been thrown out. > > But it looks like I'll need to chew up some 1/2" stock in the lathe, > making anchors from the screen door springs that will do some counter > weighting on the G0704. A 6mm Allen head cap screw with a 20mm long > spacer, and a 1/8" deep and wide groove should make it a pull out the > spring and drop the loop over it anchor point. Easy to change springs > if I should stumble over some wound from a larger wire. These, at .052" > are a bit lighter than I'd like, but they should help. McMaster has a nice selection of 3' long springs of various OD's, wire diameters, and spring rates. They seem reasonably priced (~$5-$10) in sizes likely used for this type of application - http://www.mcmaster.com/#extension-springs/=122u4yj.
I'm curious if anyone has compared moving mass (pulley/cable/mass) vs springs for counter weighting a G0704. Other than ease of implementation, space requirements, etc., any real world advantages/disadvantages of either? ie Z axis repeatability? Any thoughts on the "right" amount of counterweight? 1/2 the head weight, more/less? ------------------------------------------------------------------------------ Find and fix application performance issues faster with Applications Manager Applications Manager provides deep performance insights into multiple tiers of your business applications. It resolves application problems quickly and reduces your MTTR. Get your free trial! https://ad.doubleclick.net/ddm/clk/302982198;130105516;z _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
