On Thursday 16 July 2020 20:25:40 Frank Tkalcevic wrote: > It took me a while to find the right settings for my printer - in fact > it was more about finding a decent priced, decent quality filament. > (eSun seems to be the best in my neck of the woods). > Not seen any eSun here. I bought two kg's of black overture brand with it. I have managed to get a couple 32 tooth XL pulleys, but even there, hair can be a problem.
How fast are you telling the slicer to move it? > Hair can be removed with a quick blast with a gas torch, although I'm > surprised this is an issue as the outside perimeters should be a > continuous line. Hair usually appears with rapids. There are > settings in the slicer to avoid crossing perimeter when rapiding. I'll check those but ISTR its on by default. Currently have it moving at 25 ipm for straight line moves, but its obviously much slower when its doing the zigzags, but the laydown there has so much broken fibers the black is grey. Raising the nozzle temps, and slowing the nozzle fan to a max of 75% doesn't appear to have affected it one way or the other. Could there be too much fiber in the PLA? In that event, how would I discern the low or finer fiber PLA from the advertising propaganda? It came with a small hank of semi-white, might be nylon but I've no clue what it actually is. Sealed in a clear poly bag, along with an unlabeled nozzle and entry connection for the feed tube from the ejector motor. Looks to be the same size as the black stuff but has that faintly translucent color of nylon. Might be enough to make two of this sprocket. Not enough to get familiar with it and make good stuff. This ones no better than the first, might be the thicknes of my "rim" is preventing the slicer from generating the right code, the inside wall is nice, the tp and bottom are nice, but the teeth are porous like infill would be, so next pass is back to openscad and reduce the bore to give it more room to wiggle. If that doesn't help, screw it, as I'm about 20% done motorizing a BS-1 for use as a 4th axis on my GO704. I've bought a 100/1 worm drive and while I don't have the shaft adapters made, I do have one of the new 3 phase nema-23 stepper/servo motors bolted to the worm face, a 3NM motor, seems to have enough giddy-up to drive the worms rubber shaft seal which is fairly tight and draggy. That 100/1 ought to turn the BS-1's worm under load. I replaced a 1600oz/in nema 34 on the Sheldon's Z axis with one of these, and its running that with virtually no heat, 40 ipm faster than the big motor could move it. Crawling along at carving speed, I can run a carbide tool into the stationary chuck and make it error out, without chipping the carbide. A definite improvement since the 1600 could and has crushed 50 bucks worth of chips, and vibrated everything off onto the concrete floor, and this new tech moves like a ghost, I really have to listen close unless its running north of 40 ipm. Thanks a bunch Frank. Stay safe and well. > -----Original Message----- > From: Gene Heskett [mailto:ghesk...@shentel.net] > Sent: Friday, 17 July 2020 9:35 AM > To: emc-users@lists.sourceforge.net > Subject: Re: [Emc-users] question on tooth size vs 3d pulleys > > On Thursday 16 July 2020 18:21:28 Frank Tkalcevic wrote: > > > So what I'm asking is, has anyone printed a pulley > > > that fits & works with these smaller, finer toothed belts? > > > > I use GT 2mm, 20 and 40 tooth pulleys on my robot arm. Printed on a > > Prusa i3 Mk2.5, 0.4mm nozzle, PLA. PLA is fine - other plastics may > > have shrinkage problems. > > I'm tying to do a 240 tooth GT2_2, but not having great luck. Just the > outside rim as I intend to put it on smooth alu disks to make a 2 > stage geared way down drive for a Meade DS-10 telescope, a drive that > can be controlled from stellarium running on a pi4. I've just 15 mins > ago started the second pass after reslicing it with a 10C raise in > temps. to 210 and 65. The first one might work, but it would need the > GT2 belt mashed into it as there a lot of hair where the teeth belong, > and my theory is that the improved cooling from an after made nozzle > fan, is cooling it to fast for good sticky once it gets away from the > bed, so it tends to drag it along as the head moves. We'll see in an > hour or so if the teeth are going to be well enough defined to be > useable. If this helps, then I get some of this belting and see it > its the right size. The 5x5 cube code I was sent, measures fat, but a 32 > tooth for XL belt tests as small, so I've expanded the xy scales > until a pulley made on it actually fits in the belt w/o a slack loop > in the back. > > I'll likely have to repeat for this much bigger pulley. If I can get > useable teeth. And from the slobbering I'm getting, I suspect I could > drop the steps/100mm of string by around 5%. Thats alright as it came > OOTB totally starved for string. Set for about 19% of what it needed. > > Thanks Frank, you are keeping me from giving up. > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > Cheers, Gene Heskett 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) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis 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
