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GSully
01-15-2018, 02:43 AM
New to 3D printing - kinda obvious! Ben printing 3Dlabprint parts to Stearman airplane. I've been happy to recently. The parts are now looking stringy and not sticking. Instead of smooth sides it looks like Nabisco Shredded Wheat with gaps and very weak. I went back and re-printed some parts and I'm getting the same proble. I've made sure the system is not plugged up. What do I check for next?

charentejohn
03-19-2018, 12:49 PM
Hi, new here too and have had (think it is fixed) the same problem. I am printing a 3dlab P47, I have posts on it on the rcgroups forum, same user name.
I was getting bad layer adhesion and annoyingly occasional shredded wheat about 2/3 of the way up a wing.
For the CR10 itself, one problem was the screws holding the horizontal bar to the vertical Z axis bar were loose, so it was fine till it 'jumped' a bit then it missed a line.
Still getting that with some prints, what follows seems to work.

Main settings are Layer height 0.2 Line width/wall line width 0.42 (or higher, I used 0.48 for the fusilage) Wall thickness 0.6 Print temp 215 bed 56c flow 104 print speed 60 but all others, wall speed inner wall top/bottom speeds set to 30. I think the important thing is temp and slow speed, takes ages but works, should cure your problem.
Things that may make a difference are as follows but if you have different settings no problem.
Travel speed 180, skin overlap % 4. Retraction 4.5mm at 25mm/s extra prime 0.6mm3 (I don't get any stringing but you can see ridges outside where the inner supports are.
I had problems with the trailing edge lifting so used a 6mm brim which seems to have sorted it. I have this on masking tape with glue stick applied just before it starts printing so still sticky. Works ok for me.

One thing you can consider is ambient temp, I have mine in a box and it prints better if covered, try a large cardboard box you can fit the printer inside, cover the front with a bath towel, for me this gets up to 25c+ and makes for better thin wall printing.

Last but not least, I printed all fusilage parts and first and last wing parts ok, after much messing and struggling with settings(and have a carrier bag of useless parts to prove it). I have all but the two inner wing sections to do and am having problems when they get higher up the wings, shredded wheat again, so I used Ideamaker (free download) to cut the parts into smaller sections, have to be glued anyway. I was having problems where the servo goes in the wing, all layers separating, so I split it into 3 parts and now prints ok.
I am slicing using Cura as it allows the 0.6 wall width, parts are slightly over specified weights but not much. I find Cura overestimates weight by 5g on most parts and underestimates time 7h is 8h.

Hope this helps as I struggled with this, still needs some minor changes sometimes but seems to be right for the 3Dlab planes.

Good info here
https://support.3dverkstan.se/article/30-getting-better-prints#basic-maintenance haven't really read this bit yet but this section was useful https://support.3dverkstan.se/article/23-a-visual-ultimaker-troubleshooting-guide