Top layer fill issues

[Snuffleupagus 1]

Hi all

Having trouble getting my top layers to fill in properly, plus they're not a very smooth finish. If anyone could give me any guidance at all, it would be much appreciated. I feel like I could spend a life time tweaking parameters without ever getting anywhere.

Attached images show three test cubes. The only real difference between the three, is that they have progressively more layers on the top and bottom. Just adding more layers isn't really giving me the finish I'm looking for though. You can see the sides have a nice finish on them, but the top and bottom are looking a bit rough to say the least.

Using Cura and printing on a Wanhao i3 Plus using PLA. If you need more details, please just ask. 

[Snuffleupagus 1]

Other details if they are of any help.

 

[Job_van_gennip 23]

Could you send me your settings? Especially the infill and top bottom thickness

[Snuffleupagus 1]

More details attached, these are all the setting sI currently have switched on, let me know if you need more details.
 

thanks
Snuffy

[Job_van_gennip 23]

The setting look good, does it print the bottom right?

[Snuffleupagus 1]

The bottoms aren't great, see attached.

They're printed on a standard raft. 

[Job_van_gennip 23]

Have you tried printing them with a brim or skirt and seeing if you get the same problems?

[Snuffleupagus 1]

No, not yet, I was more concerned with the top finish than the bottoms... trying to take on one problem at a time! 

[Job_van_gennip 23]

Yeah if the bottom has the same problem it will probably have to do with the extrusion with

[Snuffleupagus 1]

Would that just be a case of bumping up my 'Top/Bottom Line Width' from 0.4mm to 0.8mm or similar?

[Job_van_gennip 23]

No you need to get a good value for this, normally it is 80% of your nozzle diameter or something. But this could cause impurities.

[Snuffleupagus 1]

I believe the nozzle diameter is 0.4mm, so I'd need to knock my 'Top/Bottom Line Width' to 0.3mm???

[Job_van_gennip 23]

Could you try with 0,35 first this is the standard setting. And could you then post a picture of the result. Also print with skirt or brim

[Snuffleupagus 1]

Big thank you for your help Job, it's really appreciated.

It will probably be next week before I can look at this again. I'll get back with the results though.

thanks
Snuffy

[gr5 2,167]

It's hard to tell looking only at the top of the parts in the first picture - the problem looks like underextrusion but this could possibly be not enough top layers or infill insufficiently dense.  But I'm pretty sure it's underextrusion.

 

Looking at the second picture of 3 cubes - that's severe underextrusion.

 

It could be soemthing isn't tight enough in the extruder.  Or maybe you are printing too fast or too cold.  This is not an Ultimaker but an Ultimaker can push on the filament with about 5kg of force. That's a lot!  With an ultimaker here are max printing speeds...

Here are top recommended speeds for .2mm layers (twice as fast for .1mm layers) and .4mm nozzle:
20mm/sec at 200C
30mm/sec at 210C
40mm/sec at 225C
50mm/sec at 240C

 

So my question is: what's your layer height, line width (all of them), print speed (all of them) and nozzle temperature.  Does it exceed the volume of filament in the table above?  If not is there a way to tighten up your feeder so it squeezes the filament harder?

[Snuffleupagus 1]

Managed to do a test print this morning, it's still running as I type this, but it is already a huge improvement.

The key appears to have been the heat vs speed I didn't have the head hot enough for the speed and I spotted a mistake with the material diameter setting too.

If I have any more feedback I'll be sure to post it up. Thanks to both of you for your input, it's most appreciated. Hope this thread can be of use to others with similar issues.

 

thanks
Snuffy