Guidelines for Printing with Thick Paste Extruder

Choose your Filling carefully

A successful thick paste print depends upon selecting a filling material that is of the correct consistency. Too thick or too dry and the material will be difficult to push through the nozzle. Too much liquid or moisture in the filling will cause it to simply flow uncontrolled out of the nozzle. You will need to experiment when trying a new material, and make sure that the paste will come out of the nozzle under control and also that the layers bond to each other to create your model.

Good results have been seen with these examples:

• Soft cream cheese
• Hazelnut cocoa spread
• Pâté
• Pudding
• Jelly-type desserts made with starch 

Therefore, the best to choose from are products containing a lot of fat instead of water. If you feel courageous, you can try adding starch as a gluing agent, but remember that it tends to behave unexpectedly in inexperienced hands.

Tips for best print quality

• Temperature

You can preheat your food before inserting it into the syringe. However, you need to remember, that if your mass is more liquid than solid-state, it will flow down the nozzle.

• Filament diameter

Before you generate gcode, remember to change the filament diameter in voxelizer. The lower the number, the higher the pressure exerted on the piston. From 10 to 15mm works fine for most of the food products.

• Layer count

Number of layers are determined by the properties of the mass. For cocoa spreads like nutella, we do not recommend more than 6 layers, but for pate up to 20 will be fine.

• Path width

It also depends on the mass properties. Set it between 1mm to 5mm and remember, that wider path means more pressure put to the piston and larger extrusion.

• Travel speed

This parameter won’t matter, unless you choose to use retraction. When travel speed will be too high, moving extruder could harm your print.

• Print speed

At first, set it to 1mm/s. When in your opinion the amount of extruded mass is too big, set it to 2 or 3mm/s. Precision needs time, but if you want quicker results, adjust filament diameter or path width. The faster the print speed the higher the filament diameter or path width (or both) needs to be.

• Extrusion

Always extrude some of the paste before you start printing. This is first way of testing, how the paste you prepared is behaves. If you made it too dry or too moist there is time for some changes now. What is also important, if you extrude some of the mass at the beginning, you will be sure, that it’s placed just at the end of the nozzle.

• Retraction

• Retraction amount

When using typical filaments for 3D printing, retraction is quite handy, but while printing with thick paste we recommend to use it with caution. Food tends to create air bubbles that can lead to final projects defects. The thicker the mass, the trickier the retraction. At first, try not to use it but if you need to, do it gradually.

• Retraction height

This is quite handy, but you can’t set it too high, because if your mass is too liquid it can stream down and harm your project. 2-3mm should be enough.

• Choosing shapes

It is pretty obvious, but always start with some simple ones. Begin with 2D and add some layers to see how the mass is behaving. If the layers don’t collapse under their own weight, it is time to  start with real 3D. Right now, we can assure you, that 3D will work with pâté or soft cream cheese (like Philadelphia) but won’t work for chocolate.