Have you contacted Prusa for help?

(18-Oct-2019, 04:34 AM)voodoo614 Wrote: Have you contacted Prusa for help?

TBH, I didn't even think about doing that but it's an option.

I ran up Cura 4.3 and applied the same settings in Cura as in that guys video that I linked to in my previous post, then I sliced a print of the front camera cage bumper and generated G-code from Cura and did a print. The results in the photos below speak for themselves. I then tried translating what I thought were appropriate settings from the successful Cura slice across to PrusaSlicer and generated G-code in PrusaSlicer which I then did a print from. The result was car crash #2.

I'm really happy with the print from the Cura G-code but it looks like I have a lot of work to try and find out what settings I need to change and/or translate across to PrusaSlicer in order to mimic what Cura is doing. I could of course just use Cura but I've got used to PrusaSlicer and actually prefer it over Cura, so I want to try and get it working.

One good thing this has proved is that there is nothing wrong with the mechanics/electronics of the printer and nothing wrong with the TPU filament I'm using. It is all down to slicer settings.

   

Come on, they look like mirrored twins. One handsome and one ugly. That is quite a difference.

Have you read this?

https://blog.prusaprinters.org/how-to-pr...-filament/

(18-Oct-2019, 02:14 PM)voodoo614 Wrote: Have you read this?

https://blog.prusaprinters.org/how-to-pr...-filament/

Yep. I think I've pretty much read or watched most of the resources related to printing TPU that is out there on the web.

I decided to use exactly the same Cura slicer profile settings as I'd used to print the pristine looking camera cage bumper bar and use those same settings to print that upright end section of the main front bumper bar which went horribly wrong before. So I generated the G-Code in Cura and kicked off the print expecting great things. Below are the results. So even worse than my original prints using PrusaSlicer 

It seems that you need a degree in all the slicer settings to know exactly what to use on a per print basis with the same TPU. I've already spent way too many wasted hours of trial and error trying to figure this out. I may have to reach out to Prusa to try and get some of their help.



   

It looks like you have a few different issues going on there.
I'd say the biggest issue is "under extrusion", causing voids. But what is the under extrusion being caused by ?
The next issue is "stringers" , a lot of times stringers are dealt with by using aggressive filament retraction. Which can cause under extrusion if it is not restarted in time
Stringers can also be caused by to much vertical lift when retracting.
It has been a long time since I used Cura and have never used Pusa's slicer. So these are general suggestions.

Turn off "ooze control"  and lower vertical lift during retraction. Or turn off vertical lift too. This however will keep the nozzle in contact with the work even if it is not extruding. the benefit is you won't get stringers, but you may get little blobs on the sides. The downside is it will be rubbing your part and could make it move or come off the build plate if it does not have a firm base or brim. Also see if you have a setting for "crossing open spaces" and the choices for that.

So it really does come down to getting your Phd. in "Slicer Settings"      ( if it was easy everybody would do it right ? )

I would try and get the print to be solid first ( no voids ) and then try and deal with the stringers without changing the amount of material being extruded.

Not sure if that helped or just confused things more  


Scott

Thanks Scott. I think I need to take a break from this, have a rethink and then come back at it from a fresh angle. Frustration is probably muddying the waters and making me try random setting changes that might not be logical.

For now I've just printed a pair of pristine camera cage bumpers using the Cura sliced G-code and stuck them on my Acrobrat frame. So at least I got that out of this exercise if nothing else so far. It's just a shame I couldn't do it in PrusaSlicer because in comparison I hate the user interface of Cura.

I still need to do all the other printed parts though so until I have got over this issue I am currently stuck.

Refreshing to see a real world use case of the i3 from a novice printer rather than people slobbering over the thing with compliments all the time. Thanks for your ongoing chronicle! Your experience does make the price of a Lulzbot Mini 2 look more tolerable in my eyes though...

I took a shot at your project today. This was my first and only attempt so far. I think it is usable. If I were to do it again I would skip the outboard support. The print barley touched it. I would also make 2 thin inboard supports, no need to touch the whole length.

I did not feel like changing the nozzle , there was a .3mm in it and this was printed with that. I also ran real slow, about 250-300mm/min. I also let it go slower if layers are less than 15 seconds. I turned off ooze control and retraction. Layer height was .15mm





Printed on mirror









Scott

Thanks for doing that. At least it gives me hope that it's at least achievable in a vertical orientation. For now I've lost the will to live with it all and have just put it aside for the time being.

I see that there's a fully featured trial version of Simplify3D available so I might as well try it. Prusa have already created i3 MK2(S) & MK3(S) printer profile settings for Simplify3D (HERE) so that will also get me the correct settings for my printer.

I'm not familiar with the way Simplify3D works but I assume there is a way to export print and filament profiles. If there is, can you please share the settings you used to do this print and I will install the trial version and see if your imported settings work for my Prusa i3 and the Surreal branded TPU that I'm using. I'm not sure if it matters but I'm running a 0.4mm nozzle on mine.

No problem, I was curious too
The thing I like the most about Simplfy3D is the ability to change settings anywhere on a per layer basis. Like inside out for the bottom half and outside in on the top. I have printed a ball like this with no internal supports.
I would be more than happy to share anything you need !! When your ready of course ; ( you need to get your will back first )

Scott

So after my previous disasters with printing TPU using PrusaSlicer, I haven't attempted to print TPU since back in October last year. However, with a necessity to get an Immortal T antenna fitted and the RunCam 5 black mounted to my quad, I was recently forced to pick this back up again because both of those items need TPU mounts.

Finally I seem to have cracked it and the result is that I'm now managing to get some decent TPU prints using my budget TPU filament. I was beginning to blame the cheap filament but it turns out that it really is all in the profile settings. Below are the results. Both items are from Thingiverse so none of my own designs, although I did have to remix/modify the Immortal T design because the one I got was for an Alien frame which I discovered is 6.5mm narrower than my Martian II frame, so the mount was too narrow and the stand-off holes didn't line up. I only discovered this after printing the original mount for the Alien thinking it would simply just fit the Martian.

Based on my previous experience with TPU supports, I wasn't sure whether to attempt printing the camera mount without them but I decided to take a gamble and did that. Unfortunately it didn't quite pay off and you can see that one of the mounting feet is deformed which is because that part was printing as an overhang. So I'm going to need to print another camera mount probably using supports in some way for that particular section. It was printed in the on it's side in the orientation as shown in the last photo. If anyone has any tips for printing that overhang without it getting deformed then please let me know the best technique to use for that.

         

Looks good

Thanks Voodoo. After all the frustrations I had with TPU, I now feel like having a party  I'm glad that I can now continue using PrusaSlicer for everything including TPU and don't have to resort to Cura just for slicing TPU prints.

The Immortal T mount works really well and it looks good. Now I just need wire up the Crossfire Nano RX and I'm then all ready to roll with CRSF  I will likely get rid of those tubes that house the R-XSR antennas once I'm happy that the Nano RX is all working fine.

On the flip side, even though everyone says that the RunCam 5 fits in a GoPro Session 4/5 mount, I've now found that while it is so, the fit is less than ideal due to the differing external profile of the RunCam 5, so while the dimensions of it are the same as the GoPro Session 4/5, the profile differences of the RC5 cause the mount warp/distort/bulge in places it shouldn't, and that really isn't any good for my OCD I might therefore have to try and find another mount that is specifically designed for the RunCam 5 and if need be, remix it with an appropriate mounting base for the Martian II frame.

        

Lookin' good.

Deal