Measure your filament at several different spots with calipers and make sure that the “filiment size” setting In the slicer matches your measurement exactly.
> On Jun 2, 2020, at 4:57 PM, Gene Heskett <ghesk...@shentel.net> wrote: > > On Tuesday 02 June 2020 16:37:08 Chris Albertson wrote: > >> I just printed a set of 3mm pitch GT3 timing pulleys with my 0.4 mm >> nozzle. They came out just fine. >> >> The final profile of the pulley tooth is not determined by the >> nozzle diameter it is limited by the step size on the printer. My >> pulley fit the belt well enough that tooth shape is not the limiting >> factor. On my case it is runout, not tooth shape that will cause >> the greatest error. >> >> Think of an end mill cutter. I can make sharp corners with a 12mm >> diameter end mill. What I can't do is make less then a 6mm inside >> radius. Same with the nozzle but backwards. A 0.4mm roud nozzle can >> make at best a 0.2 radiu corner while the 0.2 nozzle can print a 0.1mm >> radius. But the printer steps are that size and introduce a larger >> error than the nozzle. In any case what you really care about is error >> in motion transfer between the pulleys. Runout matters but a tiny >> radius error on an outside corner does not change how the belt sits in >> the pulley. >> >> There is a big disadvantage to 0.2 nozzles (1) they clog up and need >> cleaning and (2) printing is about a lot slower. >> >> Your first step before printing pulleys is to print a cube. Use CAD >> software so you know the exact dimension you specified, run it trough >> the slicer, print and measure all sides and angles. Get those >> measurements good enough. >> >> When designing with plastic, you have to make stuff bigger. Use the >> largest pulleys that will physically fit and this keeps the percent >> error down. >> >> I any case my A6 primer is the same as your Ender except mine uses >> ground steel rods for track and yours uses extrusions, But everything >> else is the same all down to the Merlin firmware. My 3mm pitch by >> 9mm wide GT3 profile pulleys came out pretty good. I had to make >> the flanges wider as the aluminum pulley design has tapered flanges >> that came to a point. I made them thicker and blunter and used a 20mm >> center bore. Odd that I could print the tooth profile just fine >> but not the flanges. >> > I'm about 90% done with a 10 tooth XL, and not at all impressed by the > actual tooth profile as it has lots of voids. Supposed to have a top > flange, but its not gotten there yet. The bottom was supposed to be > about 10mm thick so the captured nut would have lots of meat around it, > but its not sitting flat on the bed, came loose in the first mm and the > hub section is way thin, guessing 6mm is all. Cuda had a profile for an > ender 3 pro, but this isn't showing me its optimum. Done. Looks like an > XL belt will fit, the flange looks usable. Had to dig out the nut > pocket as it had the first layer laydown across it, but I've no clue > where I might find a nut that small. Even the base hub is semi > transparent like the PLA feed was too slow to fill 100%, I can hold it > up in front of the monitor, shade it from the overhead lights and see > flashes of light coming thru between the strings in the nominally 6mm > thick base hub. I wouldn't call that more than 25% filled. And the > teeth are edgy enough to affect the service life of the belt. > > So, redo it for a 10mm thick hub, and turn up the extruder feed to get > better fill? Or reduce the xy feed rate, giving the pla a better chance > to fill? Which stands the best chance to getting something usable on the > next pass? Then I need to make a bigger one, 28 or 32 teeth. To serve > as the Z drive on the Sheldon, first match the current tooth count just > to see if a 3NM motor is froggy enough.. Mainly because I have spare > belts for the existing rig. What I have obtained is a nema 34 to nema > 23 adapter, and that won't change the belts tooth count since the motor > shaft won't move laterally. > > Stay safe and well & thanks Chris. > > 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
