I am a first-time Bambu Lab customer. I purchased a new H2D a few weeks ago. I have had really good luck with PLA, but I am really struggling with nylon.
OK, first up, part geometry has a big role to play here. If you have many walls enabled, you’re increasing the propensity for shrinksge significantly. Long, uninterrupted sections generate more shrink forces than broken sections.
Next, try printing a PETG raft under your PA6 parts. Use the textured plate for that.
There are also better plates for nylon than the ones Bambu sells. Darkmoon sells many specialist plates that would be worth checking out.
I also purchased this machine for this purpose and have struggled with adhesion. It iss the long runs of filament that shrink the most and eventually pull up the corners because the forces have to be balanced somewhere.
The success I have had was mainly down to bed interface surface area optimisation. Reducing the contact area patch dimensions as much as possible, breaking into several smaller contact patches and using ABS as a support material. Maybe even using an ABS raft. I do use adhesive, Magigoo PA seems good, but so does Filaform regular TBH.
I am told a Garolyte plate is the business for PA but have not stumped up for one yet, interested to hear if others have had success with this. Noted that BL dont offer this plate type yet.
FWIW, I just made a part on my H2C with BL PAHT-CF that was flat with a relatively large footprint that also needed high strength (as solid as I could get it). I couldn’t break it up into smaller sections (footprint) due to the requirements, nor apply most other warping mediation techniques. What saved the day in the end for me was a wide brim, increasing the adhesion area. DarkMoon Satin plate, no adhesive, 110°C first layer, 100°C for the rest (default BL PAHT-CF profile otherwise). Preheated chamber and plate. 4 walls & 50% honeycomb fill.
-Max
PS. Oh and make sure printing speeds are all set appropriately for the nylons… most H2 profile speeds are way too high by default (though should be limited by maximum flow rate in filament profile).
The real solution is using a G10 print bed. Nylon bonds to the bed without any adhesives and prevents all warping, when the bed cools down the print pops off the bed. I print a lot of nylon and G10 has been a game changer, just like the Frostbite plate for PLA/PETG/ABS.
If you dont print nylon often enough to warrant a new purchase, the PETG raft mentioned works great as well.
Double check the temperature of (each part of) the bed. The H2 series bed heater is a bit derpy and does not evenly heat the bed. (I generally add +5 to the temperature in each of the filament profiles).
EDIT I don’t know which Bambu that is. Looks like an A1? But that’s how the H2 heater works. (actually seems big for A1 might be a disassembled H2)
EDIT2 I forget some non-engineers here. The heater is the copper coloured wavey M or W shaped “wire”. Obviously if your print is like 2/3 the length of the bed, the ends will set in the gap where there is no heater.
the newer Kdeavi plates (there is a “new” green one available now) claim to support pa6-cf/gf as well. anybody have any experience with one of those? I understand kdeavi was the oem for frostbyte?
problem.for me is g10 build plates have very high shipping costs.
Depends on the vendor and the formulation. The only way to know for sure is to run a volumetric flow test and use that to cap the max print speed. So for example, say you measure 10mm^3/s max flow. Using a 0.4mm nozzle with 0.45 wall thickness and 0.2mm layer lines, that’s a print speed of roughly 111mm/s (10 / 0.45 / .2)
If the vendor prints on the spool (for example): 50-150 mm/s then I’ll start with 100 and assume an initial max volumetric flow of 9 or 10. If it’s a HF nozzle then maybe 15.
I’ll still though run a volumetric flow test to dial it in better rather than rely on a guess.
