Top and bottom Layers are coming out bumpy.

[Dramitri 0]

Hello I've been having an issue with some prints coming out bumpy and was looking for some advice. I'm printing round scales for scalemail costume armour and Ican't seem to get them to come out smooth.

I've tried every resolution, speed, and nozzle size, I've also tried using the "Iron final Layer" setting. Any ideas what's wrong?

I've included the top and bottom of the finished scale as well as the first layer.

 

[yellowshark 153]

The top surface is probably pillowing, i.e. you are not printing enough layers to close out the surface. Also/alternatively your fans are not running at 100% - I am assuming you are using PLA. With 0.3 layer height you will need at least 3 top layers, personally I would use 4 minimum to get the job done. You can always dial it back if you watch the print and see how many layers you do need.

Generally speaking the thinner the layers the more top layers you need. So with 0.15 layers you will need at least 6 top layers but probably 8. Then in addition with the thinner layer you may need another 2 or 3. As before specify enough. Watch how many you do need and dial back if required.

 

The bottom layer. I suspect this is over-extrusion and/or the nozzle being very close to the bed; nothing wrong in that but you need to compensate. I always run my nozzle/bed distance very tight and print the 1^st layer at 70% flow to compensate

[Dramitri 0]

Thanks for the reply. I'm printing pla with a .4 nozzle, .2mm height, .3mm width, 100% fan speed, 4 top and bottom layers. I'm printing just close enough to get good adhesion and have tried pulling away from the bed to see if it solves the issue but it didn't make any difference beyond creating poor adhesion. I will try to lower the first layer flow tonight. 🙂

[yellowshark 153]

Hi I suspect 4 top layers is a problem, that is only a depth of 0.8mm, I tend to aim for 0.9 to 1.2. And your infill % of course will impact this - the denser the infill the quicker you will close the surface.