On Thursday 29 October 2015 11:28:30 Bruce Layne wrote: > tormach ER-20 adaptor... Those are very > nice, but run the cost per tool up about > $50/tool so I only have one adapter and > 3 collets > > > I suggest you search eBay for the TTS compatible collet holders from > our Chinese communist capitalist friends. I have a 50 position tool > rack full of those, and I'm cheap, so they must not be anywhere close > to $50 each. The quality is quite good. There is no groove for an > ATC, but that's not a big deal for me and it'd be an easy feature to > add on a lathe. > > I found them for you. :-) $16 each in quantities of ten on the slow > boat. Maybe less if you search longer than the minute I spent. > > www.ebay.com/itm/161733955633
Nice, and the price is quite decent, but shipping at $60 is apparently his profit margin. If you listen carefully you can hear the gears going around in my card case. And the dice rolling in the background. :) Now to find some ER-20 collets at a decent price. Anything in the under $30/kit range is from 1065 steel, and could be done better in a harder alloy. I think I would probably be better off buying 3 more of the 3 packs from LMS, so I would have the ability to hold more than one 1/4" tool at a time. Using 'Merican tools, I don't often need a metric collet anyway. But then I'd need to design a soft bottomed catcher bucket since its virtually impossible to loosen the drawbar bolt, and catch the er-20 adapter as it freely falls out. I have had it drop, point first, damaging both the point and the workpiece, 3 times now. I did find some 1/4" stop collars, so I at least have a consistent stickout for as long as the tool lasts. > > This has got me to thinking of a tool > changer device since I am spending > about 1/2 of my time changing tools > & other preparatory stuffs. > > > You probably already know this, but the poor man's power drawbar is an > impact wrench to turn the drawbar. There are pneumatic versions with > air cylinders to push a small butterfly impact driver down as it > spins, but I'm an electrical engineer so I like electrical solutions. > :-) > > It's hard to beat the lightweight 12V Porter Cable cordless impact > driver from Lowe's. It reminds me of the Heywood Banks song about the > Garden Weasel (search YouTube) - it's half the effort and twice as > quick! > > I have an old beat up Harbor Freight cordless impact wrench that a > friend gave me to use to make a power draw bar. I was going to wire > it so it used full voltage for reverse and half voltage for forward, > so it would tighten enough to hold the tool in the spindle, but would > always be able to loosen anything it tightened. Sort of like those > tanks that have the highest gears in reverse so they could get out of > a bad situation faster than they got into it. > > I have all the parts to make the CNC controlled power drawbar for my > mill, including a couple of large SMC air cylinders, a stack of > Belleville washers to tension the drawbar when the air cylinders > aren't pushing down on it, and a big pile of steel to build the beefy > frame that mounts to the cast head of the milling machine... just as > soon as I get a Round Tuit. > > Good luck with your woodworking and have fun! > > On 10/29/2015 10:22 AM, Gene Heskett wrote: > > Greetings all; > > > > This particular carving project uses 3 different tools which must be > > changed 4 times per end of a board processed. > > > > This has got me to thinking of a tool changer device since I am > > spending about 1/2 of my time changing tools & other preparatory > > stuffs. > > > > At present, this thing has an R8 spindle, but I haven't tested to > > see if the spindle motor has the muscle to run the draw bolt if the > > wrench is held. I'd assume so if the gear selection was in low. > > > > However, putting it in low isn't easily done by hand. That big knob > > on the side is big for a reason, which is to give us a good grip to > > shift it with. It is, IMO, needlessly difficult to switch gears. I'd > > assume it is easily replaced by a longer lever, which could then be > > swung by a smaller motor to effect the gear change. This is the OEM > > spindle motor, rated at 1 HP when driven by the OEM SCR/Triac > > controller, but with Jon's PWM servo driver with about 110 volts of > > DC power, can be run 500 revs faster than the OEM controller I took > > off could run it, and is full power reversible, running a G33.1 > > rigid tapping cycle very nicely. I write it to "peck" the bigger > > taps above #10 or 5mm of course. > > > > So there is, for short duration efforts such as dropping the tool, > > or pulling the next one back in, likely more than enough torque to > > do that. Less torque needed there than in running the nut on the > > tormach ER-20 adaptor with a big Crescent wrench which is what I am > > presently using while the spindle is pin locked by the brake I made. > > Those are very nice, but run the cost per tool up about $50/tool so > > I only have one adaptor and 3 collets (sp?). > > > > Does anyone have any experience with this? Or am I just a beggar, > > wishing for a free horse, and designing my own saddle? > > > > Cheers, Gene Heskett > > ---------------------------------------------------------------------- >-------- _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users 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> ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
