Printing in ASA Filament

[Surcouf]

There have been many discussions on what filament to use for printing hulls. Each type has their benefits, and negative aspects. ASA is great for handling heat and UV, but is challenging to print with. These challenges can include prints that are not as nice in appearance as PLA, higher bed and extruder temperatures, and bed adhesion/warping.

I have printed hulls for 3 submarines in ASA, and working on a fourth right now. I feel that I have locked in parameters that work for me, and feel that others may benefit from this information. If you have struggled before, or worried about attempting to use this filament, maybe this might provide guidance to have success as well.

I have been using a Bambu Labs X-1C for all prints so far, though I have recently purchased a Bambu H2C model that should make it easier to get the chamber temperatures, and change nozzle sizes.

• I have used Flashforge basic ASA filament.
• I have chosen to use a 0.2 mm nozzle for the fine and sharper details it produces- however this increase print time significantly. A 0.4 nozzle has worked well also.
• With the smaller nozzle I use an initial layer height of 0.14 mm, and 0.1 mm for all other layers
• 4 walls for 0.2mm nozzle, and 2 walls for 0.4 mm nozzle
• 100% rectilinear infill
• Brim with 6 mm width, and 0.1 mm gap
• Nozzle temperature minimum of 250° C, and maximum temperature of 260° C
• Initial layer nozzle temperature of 260° C, and other layer nozzle temperature of 255° C
• Bed temperature of 105° C
• No cooling fans
• Standard speeds for the X-1C
• I turn on the bed temperature manually to 105° C, and wait for the chamber temp to climb to a minimum of 38° C
  • If I do this, and then send the print file to the machine, it will be at 40° C or higher when it starts to print
  • Maintain the chamber at or above 40° C throughout the print
  • I also do not open the door until the bed and chamber temps are below 35° C after the print is complete
  • If these items are strictly followed, along with the brim, then I have had no warping or bed adhesion issues
• I use a smooth PEI build plate that I clean with dish soap and alcohol before every print
• I have had better luck with using supports on my hull sections- though I know that some choose not to.
  • I use normal supports in snug mode to minimize the support material needed. With the 0.2 nozzle, tree supports become brittle on tall prints

I also have found CA glue to sometimes be a brittle joint. I mix leftover ASA support material with acetone to a consistency of Elmer's glue, and attach hull sections using this. It essentially welds the joints together, and is very strong. It can be mixed thicker as a filler as needed as well.

I hope that others will find this as useful guidance.

[trout]

Just to add, I also mix Asa or abs in acetone and make a “putty” for filling gaps or other imperfections that need a facelift. I use straight acetone to fuse sections together.