Hello, I am trying to Minimise strings for printing my 98A TPU filament.
I am making a hollow wristband - The results are not so stellar because it creates a lot of strings. I tried a few settings (avoid crossing walls), but nothing solves this issue. Is there a way that the printer always traces the outline and not crosses into mid air?
Any suggestions?
Thanks,
Markus
Is it properly dried ?
If not I would bet that’s the problem 
Well, it was stringy right out of the box when I bought it. I’m quite sure that TPU always generates some strings. I was hoping for some slicer adjustments to mitigate this problem by avoiding unnecessary ways for strings.
I feel like the forum needs an AI to auto-post “Did you dry the filament? Even if it’s brand new from shipping, it still might need to be dried!” 
But I also await some TPU experts coming along with additional tips as far as helpful settings. Probably a lot of the same things people do to reduce PETG stringing…
Let’s put it that way - been there done that, refused as badly or worse as you make it look in your comment.
I started with 3mm NYLON meant to be used for lawn trimmers…
And that on an unheated glass bed.
I know, worst possible way to get into 3D printing but I did it because I needed a spare part part that was discontinued more than 5 years prior LOL
Drying the Nylon ???
Back then no one even considered that filament might need drying and there were no good options to do it anyway.
My prints were rough, full of strings and sometimes even bubbles - but they were strong and did what they had to do.
Had a 5kg roll of the stuff, so it took me a while to venture into other materials.
My first roll of ABS came with a shock, worse when I tried PLA…
Compared to my best Nylon prints they came out like a freshly cleaned and shiny oiled baby bum ROFL
Since then I learned a lot about printing, creating parts and how to treat my filaments, am a bit slow at times but after about 2 decades even with me thing start to sink in eventually LOL
Don’t use TPU often as I have little use for it.
But when I started I felt all this drying hype MUST BE overstating the problem.
The roll came in a very tight bag with a strong vacuum and has THREE small desiccant bags in there - what could possibly go wrong.
Basically everything…
Test print came out nice and clean but the temps were still a bit low.
Adjusted the temp and went right for my model to go full scale - bad mistake.
It came out looking like a redback spider just moved in and re-decorated.
Used the blow torch on it and felt a bit happier.
Saw lots of people doing the same, especially with PETG, so …
Looked at my rarely used filament dryer and decided it is late anyway so why not put the TPU in there over night…
And just because more and more posts claimed I have to print right from a dry box I started another print with the filament coming right out of the still running dryer.
WHAT A DIFFERENCE!
Having good settings and a good calibration is vital but for some filaments getting them into the extruder as dry as possible is even more important.
A lot of things can look fixable and one can find improvements through messing with the settings but I learned that before even trying this way DRYING can mean no other changes are required and the print still comes out much better than before.
I sucks, it takes time, it seems unrequired but sometimes drying really is the best options to start with…
Just saying…
I had the TPU in the oven for 8 hours now and it does print with better results!
But this procedure is a huge pain in the butt…
Is there another flexible material that is less prone to absorb moisture ?
Once it’s dry, work hard to keep it dry. Either build or buy a dry box (air tight box with desiccant) or use vacuum bags with a desiccant holder of some kind. Eventually you will need to dry it again but this way, it won’t be every time. You can print a desiccant holder that fits in the center of the spool or use a cotton or organza bag filled with desiccant and stuffed into the center. I use vacuum bags and desiccant and don’t dry between prints, going a month or two between prints. Having said that, if I want the best print I can get, I do print straight from the dryer. Maybe one in 10 prints?
There is a flexible PLA out there, I’ve no idea how flexible it is nor what it’s drying requirements are.
Or you could be ridiculous like me and buy so many AMS that you can pretty much use them as your dry boxes. Until you get past 16 types of filament used, anyway. 
(It is also pretty convenient, I guess.)
