Does anyone have experience printing T-Glase material?
We are having problems printing overhangs/ support with the T-Glase. If anyone has success printing overhangs with T-glase, please let me know. Thanks!
Set bridges to 6mm/s on a .4mm nozzle. Also note that speed builds pressure so keep that in mind. If 6mm/s is to slow compared to the speed of the extrusion just before it, it will over-extrude the pressure onto the gaps. 6mm/s will work on just about any infill. You will need a temp around 240, 250 is too high for that slow. I can print .1mm layer bridges and its flawless. Extrusion calibration (average diameter of filament via a caliper) is EXTREMELY important. Ive done tests and a .005mm offset is enough to mess up the bridges. With bridging, less is better as far as tglase goes, so you might try setting multiplier for bridges to 98% and test that. Thats a dirty hack though. Getting extrusion down to 3 decimal places will drastically improve prints.
I see some of you printing at 250c which is good but if you have a stock extruder with a PEEK insulator, the PEEK will melt at 260 so be very careful, i lost 2 nozzles this way and not even a 1/4 inch of high strength JB weld will help you. Also, not that Teflon begins to release toxic fumes at 245c and will melt around 260C so be careful there too. Only do that with an E3D, the nozzle will not last long at 250C, especially on long prints, the PEEK may even warp from the pressure of this stuff at normal speeds.
I use it to make 15 stem percs for a modular concentrate rig. They hold water. Use small layers, print hot, print slow. It takes anywhere from 12-36 hours per print. But it will work every time. Turn retraction down as much as possilbe or turn it off, and dont use a Z hop, or if you must, then keep it under 0.15mm. Z hop can mess up layer height by a few microns, which shows up when you try to fill it with water. The idea here, is that the previous layer must be above its glass transition temp, if its too cold, it wont bond correctly to keep water out. Beware, this speed at the temps required (at least 235C at 15mm/s, but 10mm/s works better and you can go down to about 3 on most machines) will make the tglase ridged. That means if you drop it, it wont have any give, it will just break in half like thick glass would. And as mentioned below, you cant do it with less than 2 perimeters. The 2nd will make sure there’s a seal and smooth the layer next to it with the span of the nozzle’s outer diameter. Skeinforge’s skin module is usefull here to speed up print time. My rigs have 3 perimeters and its about 1.2-1.5 thick depending on my setting and which piece its making. (note: i increase the nozzle diameter on prints that dont have overhangs - but you must also slow down the print to do this because its pushing more than the nozzle is designed for, and it has to be hot as well. )
Your threads are sagging because you are printing way too hot (Tglase MAX temp is 248 for reprap printing, I can also see you are under or over extruding judging from your layer lines.I don’t have any when I print, it’s solid because I set the extrusion perfectly by averaging 20 different points on the filament down to .005mm …you are also printing your perimeter too fast. The first time you calibrate it, you’ll need to re calibrate the platform height too. Too close and it will pull up the extrusion behind it as it travels, it will sort of curl upwards. Too high and it won’t stick because it doesn’t press into the platform. Remember that part. A good first layer is the key here when you have it calibrated.
One more thing i mised, max layer height on a .4 for tglase is .32, not .35… .35 is for a .5mm nozzle. It said 70-80% of the nozzle size, not the setting. You just increase the setting in addition to the layer height to widen the line
Perfect bridges take some tuning but ive found, once you measure your filament all over and average the numbers out, set bridges to 5-6mm/s and it works every time. If you over extrude by .005 though, it will show up slightly. Also try setting bridge flow to 98%. It doesnt seem to like gaps more than 10mm across. So scale infill accordingly. Also make sure the extrusion line just before infill starts, is slowed down (you can do this for that layer only, in your settings or use a script like “Tweak at Z height” (in cura)… If you move too fast just before bridging, (the difference in speed is too far apart) It will over extrude the pressure into the gaps. Low heat can do this too as that also increases pressure.
