Layers wont stick

[johanmas 0]

Tryed to print with nylon and the layers wont stick. What do i need to do?

Temp: 250c

Build plate: 60c

Nozzle: AA 0.4

 

[Nicolinux 288]

Hi,

 

did you select the Nylon profile in Cura? Did you use Cura at all? If not, which other print settings did you set?

[johanmas 0]

Yes and yes

[AndersK 59]

Wich nylon are you using? Some need more temp than others to bond good between layers. My latest nylon prints was around 270, lower and I had pieces falling off.

[gr5 2,170]

• Cover the printer completely - you want the air temp to get much higher.  Around 35C is good enough and still safe for the steppers.
• Make sure fan is at the lowest value where it still spins (1 to 3% for a UM3, around 30% for a UM2 and so on).
• Nylon absorbs water from the air crazy easily.  You might have to bake yours at 100C for a while but it looks okay - if it's totally too wet it will his and sputter and sizzle as it prints.  But there is a point in between where it's quiet but it comes out foamy instead of normal.  It looks fine in the picture though (hard to tell).
• Bed at 80C minimum - more to heat the air then the nylon.  100C bed is fine for nylon also.
• Layer heights at least 0.1mm.  0.15 better - that way there is more thermal mass to melt the layer below.

 

Even if the cracks go away you might not have improved adhesion enough.  Purposely break a part and if it breaks along layer lines you still don't have good adhesion - it should break along random lines - not layer lines - if you do nylon right.  Actually a part this small - you probably won't be able to break it without some special tools so if it doesn't break despite your best abuse it's probably fine.