On Sunday 06 September 2020 10:20:55 Tom Smart wrote: > Have you looked at replacing your extruder with a direct drive and > building a box around the print bed. People have had pretty good luck > with these mods to the ender 3. It would be considerably cheaper than > buying a new printer. I've put the full kit from MicroSwiss on it, but the hot end was a bust, so the modified OEM hot end is back on it. The MicroSwiss was plugging solid about 2 hours into any print because hot plastic was filling up the hot block, migrating up the heat block to the cold sink and locing up solid. The OEM hot end has the plastic tubing all the way thru it and no hot metal touches the filament until its actually in the nozzle. But due to a lack of any compression against the back of the nozzle, it leaks there, running hot plastic down the nozzles threads and filling up the cheap sock until it drags on and destroys the print. I took the shark bite out of the top of the heat sink, cut that piece of the tubeing off about 30 thou longer than the space from the shark bite to the nozzle, and used the hot block as a sanding jig to make the tubing dead square on both ends so it would seal better against the rear of the nozzle. Then I threaded a piece of PLA thru the shark bite, putting about a 2-56 sized steel washer over the PLA and against the bottom of the shark bite, teflon pipe taped the nozzle and installed it. Ran the PLA into the cold nozzle, and useing it to hold the washer so the PLA went thru it ok, screwed the shark bite back into the top of the heat sink, hitting the trapped tubing about 3/4 turn from tight and drove it on till tight. Now my nozzle maintenance consists of warming it up and wiping it off with about 4 layers of paper towels to keep from cooking my fingers, in betweeb jobs.
So that part is fixed, and all I really need is a hotter nozzle. The MicroSwiss ejector drive is sweet. but I wasn't impressed with the hot end, its metallic and oversized from the built in shark bite on top, all the way to the nozzle. And when it freezes up, you can drill it out, or go heat the whole maryann on a gas cookstove fire. No amount of 260c nozzle heating will telegraph far enough up into the heat sink to thaw it out. So I put the leak fixed EOM hot end back in it, which had the side effect of raising the fish mouth on the top of their tube connecting the extruder to the hot end, nearly a mm higher, where before there was room enough for the TPU to buckle and escape, now it fits precisely. TEPG is stiffer so I can put lots of pressure on the nozzle, but I can't melt the TEPG fast enough at the 260C limit of the hot block to run any faster than 25 to 30 ipm. That limitation is in the driver cards firmware, so I'd suspect a replacement driver card may allow it to run hotter, with the limit being how hot the capricorn tubing can be run at. The OEM white, said to be PTFE, tubing is said to outgas noxious funes above 240C, but I'm currantly running at 260C for the third flexgear and haven't noted any odors. But as of Fridays mail, I have a yard of capricorn to replace it as needed. My clue will likely be the leakage. Thanks Tom. > From: Gene Heskett <ghesk...@shentel.net> > Sent: Sunday, September 6, 2020 8:04 AM > To: emc-users@lists.sourceforge.net <emc-users@lists.sourceforge.net> > Subject: [Emc-users] hi temp 3d printers, are there any cheap ones? > > Greetings all the 3d printer people hiding in the bushes; > > I have found the best material to make flexgears out of, TEPG. > > But I've a problem, an ender3 won't go above 260C for nozzle temp, and > that is restricting the build speed to around 30" max, because it > can't melt the plastic fast enough to make a solid build while moving > faster. > > Out of the parts for this version of a harmonic drivem I'd like to > make the body cap with the motor mounted to it, and the bearing > carrier because that would allow full current to the motor, and the > flexgear out of TEPG because of its flexing without failure ability. > The rest of it can be PLA as those parts don't have the motor heat > telegraphed into them. > > So I'm now looking for info on an affordable printer that can run the > bed at 80c, and the nozzle at 275 to 280C. This ender3 pro > electronically limits at 260C, and takes a long time for the bed to > hit 70C. And there are advisories about not going above 240 with the > OEM bowden tube. And I have a piece in the hot end that I'll replace > with the blue capricorn between this print and the next, because I am > running at the 260C limit, and 70C bed just to get bed adhesion. > > Is there such a beast more suitable for TEPG? > > Thanks all. > > 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 > > _______________________________________________ > 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) 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
