Keep getting jams printing T-Glase in my E3D

[Gr8Scott]

I'm really having a tough time with this. The E3D keeps jamming up printing T-Glase. I ran it with no fan accidentally today and it jammed up so tight I couldn't get the clog out without cooking it out with the torch. The jam was all the way up the barrel to the fitting. Had to be careful with the torch as I got the fins so hot they started to melt at the tips. Got it cooked out and cleaned up as much of the gunk as I could and put everything back together. It all looked pretty good until the print had been going on for a bit (with the fan at 100% power) and it still clogs about 80% of the way through a 3 hour print. I was running it very fast, so I would assume that heat creep would not be as much of a factor as I was pushing a lot of filament through this thing before it clogged again. The clog happened while I was out of the room, so I didn't see anything that might clue me in on what started it.

Gonna take it back apart and see what's up. Might have to make my own barrel if I pooched this one by cooking it... Maybe go water-cooled or something. I'm getting really tired of taking this thing apart.

[Polygonhell]

How much retraction are you running.

[Gr8Scott]

It was a single walled vase. No retraction. I normally run pretty lean retraction as I would rather have stringing than clogs.

I need to get my bling name changed from "printmaster" to "clogmaster" LOL.

[Polygonhell]

I haven't had on issue with TGlass Jamming, it is (like all later Taulman filaments) oversized, usually 1.85 +/- which can cause issues, though it's usually at the EZStruder end.

I did have issues with it printing fast at the recommended temperature, I'm running 225C (which is probably 220 actual) at ~40mm/s perimeters and I'd have to look but probably 60m/s infill.

You shouldn't have anything resembling melted filament to jam near the fitting unless you have very long retracts, so I'm at a loss how you could have a jam there.

[Gr8Scott]

Broke out the Mapp Gas torch and cleaned out the two clogged nozzles I have and then heated up the stainless heat brake and heater block on the E3D to who knows how hot (the thermistor popped out because I removed the tape holding it in). Lots of smoke and stink. Gonna rewire it and make sure everything screws together nice and tight and give it another whirl. Seems like most of the clog was in the heat brake. The nozzle was clogged as well, but not as badly IMHO. Both had some debris in them that needed burning out.

Ran the blunt side of a tiny drill bit down the throat of the heat brake and felt a lots of resistance at the bottom. Feels like there was a buildup of some gunk in there where plastic had adhered to the walls during the print and didn't come out when I heated the block up and pulled the line out by hand. Burning it out has degraded the plastic quite a bit and allowed me to push the charred remains out of the brake to hopefully restore function.

Testing it out shortly to see how this all works out. I'm concerned that there may have been a tiny amount of gunk between the nozzle and the heat brake when I tightened it back up. I have it all back together, so I'll know something here shortly. LOL

[Gr8Scott]

Almost got it working again, but I needed to make a quick adjustment to the Z Height and managed to forget the fan once again and clogged the E3D up solid again. This is quickly becoming maddening. It's not the first time I wanted to blow this machine to high heaven with any number of semi-automatic gas fed weapons, so I am getting used to this feeling LOL.

I have an early morning tomorrow, so I'm gonna give up and go to bed before I do something rash and wake up the neighbors with the sound of rapid gunfire accompanied by maniacal laughter.

[Polygonhell]

Just connect the fan directly to 12V so it always runs. Or you can use the Heat2 output and have it turn on with the hotend (assuming you haven't edited the firmware).
The Fan output is designed for part cooling, not for cooling the heated break.

[Gr8Scott]

Thanks for that info. My E3D came with no instructions and no paperwork. Instead of doing the smart thing and going to their website, I made some assumptions about the simplicity of the parts and thought "how could I possibly screw this up?" Turns out, I screwed it up sure enough. Working with this printer has been a profoundly humbling experience. LOL.

I unscrewed everything and ran the heat brake and the nozzle through another Mapp Gas bath to clean them both out. Didn't have to burn the barrel this time as it seems to have been spared from my ignorance for once and wasn't locked up like I had feared. Printing now with fan hardwired to 12v source. I'm thinking of putting a small 12v LED on the fan to indicate everything is working properly. Either that or hard wire illumination LED's to the fan so if they go out I know something is badly wrong.

Stop the presses!!! As I'm typing this, it seems to have clogged again. I really don't understand what is happening here. I think I'll clean it out again and try running ABS or Nylon or something. Maybe the material is messed up or maybe it's having some sort of weird chemical reaction with the head. Don't really know what is going on, but I do know that I'm getting dead sick of dealing with these clogs. Cleaning out clogs stopped being fun about a week ago.

[Gr8Scott]

Retracted the T-Glase (it wasn't exactly clogged, but just seemed to be unwilling to print any more) and put in some 645 Nylon and printed that for a bit. Subbed the T-Glase back in again and printed more slowly this time. Seems to be working ok now.

[Polygonhell]

If you haven't checked the thermistor on your E3D vs a thermocouple at your printing temperature, you should, both of my V5's were out by 30C (to low) at 250C.
And T-Glasse doesn't like being extruded if the temperature is too low.

[626Pilot]

Increasing speed may reduce melt creep, but it also increases feed pressure. I wouldn't even worry about melt creep since you're not retracting. Start at 20mm/sec to see if you can get it to print, at all. Also, I think they recommend using fat nozzles. Use 0.6 if you have it, 0.4 if not. They also recommend layer heights of .3 or more.

[Polygonhell]

I'm using a 0.4mm nozzle, but my nozzle is modified to shorten the bore and hence decrease extrusion pressure.
It prints fine at lower layer heights, I ram last set of prints at 0.2 and they look pretty good.

[626Pilot]

I remember discovering that my spool had segments that were too thick. They were dragging against the inside of the Bowden tube, increasing backpressure.

[Polygonhell]

I remember discovering that my spool had segments that were too thick. They were dragging against the inside of the Bowden tube, increasing backpressure.

Yes I mentioned this, all the later taulman filament is oversized, 1.85 +/-
I spoke to them about this, it's a deliberate decision to resolve an issue with a particular very popular direct drive extruder when used with easily deformed filament. Unfortunately that makes it play less well with Bowden extruders.

[Gr8Scott]

This T-Glase visually looks oversized. The 645 is much thinner looking IMHO. Very opaque with all the water that has creeped in as well. It practically steams when you print it.

I am trying to make a new/improved 'shower head' for my coffee maker. I know it's a tough call to try to print it out of thermoplastics, but is there a filament that will hold up to the heat and is food safe? T-Glase is nice and stiff when cool, but it turns into a giant wad of chewed bubble gum when near boiling point for H2O. Are there any current filaments out there that I could use? My T-Glase version is not gonna last very long.

[Polygonhell]

Using printed parts in food safe applications is really questionable, even if the plastic itself is food safe, the layer ridges are an ideal place for bacteria to breed.
If you insist on doing this, you're looking for a plastic with a glass transition temperature > 100C, ABS is 106, PET which TGlass is is more like 70. Of the printable plastics polycarbonate has the highest glass transition temp ~145, and they make water bottles out of it. It's not the easiest material to get decent results out of though.

[Gr8Scott]

There won't be anything other than hot water running through this part. Nothing there for bacteria to eat unless the water pooled there. My design won't allow any pools as there will be a drop from the water spout to this part and then straight into the filter basket from there. No pools. So Polycarbonate may be a worthy consideration then... Thanks for the heads up on that. I'll check to see if it has anything like BPA etc in it.

[Gr8Scott]

Eric posted a link about food safe printing from a different forum for me. While I'm not as concerned about bacterial issues etc, I wanted to avoid low glass transition materials so the part would last. The link mentioned brushing printed parts with food safe epoxy to seal up any voids that might be hiding places for bacteria etc. I'll just cast the entire part out of this same material so I won't have to worry about it and use acetone smoothed ABS for the molds.