Anyone get smoother prints with zero to little retraction?
 

Anyone get smoother prints with zero to little retraction?  

  RSS
thomas.b13
(@thomas-b13)
Eminent Member

Hi

I've not used my mini in a while due to issues however determined to get it working. I'm back to an issue I had a while ago (see photo) and while it did seem to go away for a while and was alot better with prusament , its come back even with prusament. Even so, only using prusament not really an option.

Long story short, this issue keeps coming back, it happened with a stock mini and also with the mini as it is now with bondtech heatbreak/extruder.

Its not the filament, the hotend had been asssebled and disassembled a thousand times, new ptfe, pushed up etc. The brass fittings finger tight.Its not z seam (thats aligned). The filament path is clear, no bits in the extruder and I've tried multiple temps, flow rates and speeds.

The only way I get a smooth surface is if I reduce retraction significantly, or if I turn it off completely. Any one else experience this?

While it maybe a solution to the problem below I then get strings all over the shop and I can't seem to find the right balance, its either smooth outer surface and strings, or no strings and a print like the below.

To me, its got to be an issue with the hotend or PTFE tubing, not sure what else I can do about it though, thoughts?

 

 

...
Posted : 14/09/2020 10:17 pm
Malcolm
(@malcolm-2)
Trusted Member

Have you tried modifying the 'extra length on restart' might be worth trying. Using a negative may help, particularly with oozing.

Posted : 15/09/2020 12:04 am
Malcolm
(@malcolm-2)
Trusted Member

Also post your STL, I will test it out

Posted : 15/09/2020 12:05 am
SS220
(@ss220)
Estimable Member

If you are printing through Octoprint, try it straight from a USB drive. I've seen this sometimes on round or organic shapes with Octoprint.

Posted : 15/09/2020 1:25 pm
thomas.b13
(@thomas-b13)
Eminent Member

@malcmcm well since I'm disabling retraction the negative restart distance wont apply. I could try lowering retraction then using a negative restart distance however to me thats not addressing the main issue, which I think is hardware related. Above its the middle bit of Darth Vaders light saber, however I get the same on the circular objects and also the non circular parts also. I've designed my own light up stand,  I just need this light saber to put on it but the mini's not having it.

https://www.thingiverse.com/thing:2890929

@stevensmith Its direct from USB, I've not hooked Octoprint yet on purpose, not unti I get to the bottom of this issue.

There is one thing I want to try, print in PETG just to see what its like. I dont have any left so ordering from prusa.

...
Posted : 15/09/2020 8:43 pm
thomas.b13
(@thomas-b13)
Eminent Member

Just an update, I have started to get better prints with a retraction of 2, and really low temps for some of my PLAs, I’m taking 185c whereas on my other printers I do 200-210. Even prusament seems better for me around the 195-205 range. 

I still find it odd it’s like this. I’m unable to test anymore as another issue has cropped up again, my z offset keeps changing so screwing up my first layer, been fine for months as long as I do a preheat to heat up the minda but now for some reason it’s decided to give up on me, this printer just keeps on giving 😞

...
Posted : 21/09/2020 12:11 am
alexander.k38
(@alexander-k38)
Active Member

@thomas-b13

I can confirm I have been seeing better settings around 2 for retraction. Testing lower than norm temps now.

Regarding z offset, preheating solved the floating issue for me, sounds like you need a replacement minda.

Posted : 25/10/2020 9:34 pm
Share:

Please Login or Register