Heatbed adhesion
While there are many discussions on what to use for plastic adhesion to the heatbed when 3D printing, we've found one very easy solution that we're always using now for the aluminium heatbed.
Here's a video of it:
Rosin flux dissolved in acetone (or spirit) turned out to be very effective for print bed adhesion.
It is easily applied to the aluminium print bed with a brush or tissue. It can also be used for several prints, as it’s not necessary to clean it off after use, and on consecutive prints the rosin layer can be renewed just by moistening it with acetone again.
With the heatbed temperature around 60-70ºC the rosin solution provides excellent adhesion for the plastic, while cooling it down to room temperature causes the plastic to come off practically by itself.
Gcode additions
Some slicers may generate gcode differently. Sometimes, you may want to manually add something in gcode. For example, I’m using Cura. After early prints I noticed that I always have to manually turn off the print bed heating and lift the nozzle up to be able to remove the printed model.
So, now I manually add a couple of lines at the end of each gcode file:
M140 S0
G0 Z40
The first line turns off the heatbed, and the second one lifts the nozzle (I change the number after Z depending on the model’s height).
Dripping nozzle
When the nozzle is being heated before printing, at some point the filament will start to drip through the nozzle. For PLA, it happens at ~170ºC. You may need to remove all the dripping filament with tweezers before printing starts.
However, if you calibrate the print bed well and place the nozzle into zero position before heating, the bed right in front of the nozzle will prevent the filament from dripping out.