Tried that with a new 1.0mm nozzle.
I love throwing my time at 3d-printers 
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I know it’s annoying, but once you have it set and understand how to debug, it’s a true pleasure…
If it doesn’t extrude with 1mm nozzle, I don’t know what to say. The last suspect is of course the extruder itself. Can you take a pic of the extruder?
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that’s half the fun!
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I’m not sure if it’s the same thing, as your lower layers do look underextruded, but if I try to print small objects with TPU, I get that melted look. The layers need time to set up before the next layer comes in. Maybe try printing something a bit larger? Usually with TPU for me, everything gets better if I slow it down way way way slow. But my TPU is all pretty hard/stiff, which is easier to print. Ah I see your stuff is also 95a.
I’ve had great luck with hobbyking 95A TPU. I think this is within AUS reach. And with their PLA for the most part, and some colors are usually on some crazy sale.
Also with Sainsmart TPU on amazon.
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Usually fails on the first layer and it’s when it starts doing the infill.
Going to just go nuts and set a higher temp. Clearly it’s having issues in the nozzle and I have replaced the nozzle, so it must be not melting.
Once I get this sorted I have many things to print (‘gasket’ for the bottom of the enclosure, AS150 anti-spark key ‘handle’).
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I think I’ve had to slow to 10mm/s for TPU, with a .4 nozzle. Infill prints considerably faster than perimeters, right?
Bad memory but I think I set a global 50mm/s speed limit, then use the control panel to slow it down to as much as 20% if I get the birds nest at the extruder.
I have no idea how to compare to your big nozzle and heater. Increasing temp seems like a good thing to try.
Oh shit sorry you’re in New Zealand not AUS. Your printers are all bowden? I’m direct drive, so that’s another difference.
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Pretty sure I have followed the advice of having the same speed everywhere. I’ll check again though.
There’s not much advice out there for printing big with flexibles, but I did find something somewhere (matterhackers maybe?) where they said that bigger nozzles make it easier.
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Never tried with big nozzle but with .4mm I printed some pretty sizeable parts but it does always take a couple days of messing with things to get it well tuned for TPU the first time around. So not surprising, but would heed advice of slow things down can usually get a better idea of what’s going on and hot end won’t be working so hard to stay hot (less heat flowing out since slower extrusion if overall feed rate/percentage speed is slowed).
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I read somewhere that going too slow was bad because the heat could creep up the filament and maybe the filament would melt too early and it would clog (?).
I’ve tried printing from about 20mm/s down to 10mm/s (and maybe even 5mm/s). I figure if it’s not working at 10mm/s then something is wrong.
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Yah sure there is some truth to that but thermal conductivity of plastic isn’t near as high as metal in general so wouldn’t be too concerned about that unless printing at a real crawl. Slowing down overall rate can help so the extruder isn’t pushing so hard on the filament and has some time to melt in the hot end before getting pushed through, have to go incredibly slow with nylon but I think I went like 80% or so with TPU to get it working without issues.
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That’s pretty easy to check even without printing right?
Just set the temp to something high say 240. Raise the nozzle away from the bed. Use the control panel to extrude 10cm of filament. And see how it comes out. If it’s flowing well and uniformly there is no problem, if not, then it’s either your nozzle is not gettt hot enough, or filament diameter is not consistent and it’s getting stuck in Bowden (you have a Bowden or direct drive?) Or extruder gear is slipping. So which one is it?
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Yeah tried that. Raised up, it extruded ok for about 100mm then the filament came out after the extruder gears and before the nozzle. Might have only been at 220 deg though. I’ll try it again.
Really appreciate all this help! I didn’t get much response on Reddit about this (and my work’s Slack either 
).
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I’m trying the test cube here will get you my rates once finished and can see if it turns out okay. Says 45 min on .2mm fast mk3 setting in prusa it looks like the main difference for TPU in prusa slicer (slic3r) is the “max volumetric speed” which is set to 1.5mm/s, the generic pla for comparison is set to 15 mm/s, normally this xyz cube takes about 20 min or half the time to print in PLA
Other notable difference the extrusion multiplier is 1.2 for TPU vs just 1.0 for PLA
Prusa slicer version had temp at 240C on hot end and 50C for bed and seems basically no part cooling fan going. The TPU is hatchbox (I think 98A)
@skelstar, check this out.
BTW, I never asked you, are you sure the nozzle and ptfe tube are flush with each other. That’s like the basic 3D printing stuff, so I didn’t ask. But all the signs points to that, now that I think about it.
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Came out really good here print temp was much higher than labelled on the box marked for 190-210 but printed at 240 feels a bit stiff but old filament not sure if product of age or temp but looks nice.
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Yeah have disassembled and reassembled the extruder a few times. Looks fine.
I may be nearly finished with my second successful print right now. Pretty happy, the XYZ Cube is at about 70%. Will post victory pics shortly.
Solution was probably 135 degs, 10mm/s and a devil-may-care attitude.
fingers crossed.
Spoke too soon. Got about 80% and it clogged. Think I’ll call it “solved kind of” and just bump the temp up by 5 more degs.
Although the spool is on bearings, it looks like it’s a bit of effort getting the filament off the spool when it unwinds, so I might look at making that a bit easier too.
Thanks for all your help! @mishrasubhransu @deucesdown @wafflejock
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Can someone recommend a PETG filament brand?
In the US, Microcenter’s Inland PETG is pretty inexpensive and well reviewed. I like it.
On the other end of the spectrum, I believe Prusament is good stuff, and available on amazon.
https://blog.prusaprinters.org/launching-prusament-the-best-filament-that-you-can-inspect-yourself/
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In the spirit of @mishrasubhransu’s post on wall thickness, I found this article illuminating
http://projects.ttlexceeded.com/3dprinting_speed_illusion.html
Sorry it’s Prusa centric, but it talks about linear speed vs volumetric rate vs nozzle size, and how to preview the speeds in slic3r. It helped me improve vase mode speeds like 5x. That site is full of deep fairly deep thoughtful articles.
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