Lifting/warping is an inherent issue due to thermal shrinkage of ABS plastic. All FMD style 3D Printers that use ABS have this challenge. The following are some tips to prevent this occurring:
- Level - [Plus/Plus 2] Make sure the platform is completely level to the nozzle - this can be a challenge to get it level, but it alleviates the warping. Under the platform you should find three screws (with springs on newer models), use these to level the platform to the nozzle.
Hot, hot, hot - For large prints, the platform must be hot to every corner, typically pre-heating for half an hour is enough, or printing immediately after another print. Also try placing one of the gloves supplied over the platform while pre-heating to create an insulating effect.
[Plus/ Plus 2] In the maintenance window, the software reports the platform temperature of the center of the table, not the corners! These corners need to be hot! Make sure the reported temperature is ~105°C for 5 minutes before print.
- Wind Barrier - Make sure this is closed during printing, or at least until the raft has been laid, then it may be opened. We don't want the material being deposited onto the hot platform to be cooled from above and heated from below creating uneven thermal shrinkage.
- Draughts/Cool air - [Plus/Plus 2] This can accelerate uneven thermal shrinkage. The most effective solution here is to enclose the printer in a suitable box. The box must not be removed once printing begins as it would be like opening the oven while cooking a souffle.
- Nozzle Distance - It is very important to have the nozzle close to the platform (0.1 - 0.2mm), too high and you'll get the raft lifting. Make sure the first layer of the raft is squished out flat.
- Perfboard - We find that the supplied perf board is the best platform for ABS prints. Make sure it is affixed to the platform properly.
- Do not - wrench, pull or grab the finished printed models of the platform - doing so will affect the level of the platform and you'll have to re-level again! Always remove the platform or unclip the perfboard.
Thanks to Andre' from C-iT for the detailed tips!