co-author: William Brent Wright
III. What Printer Should I Buy?
Things to Consider
When looking for a printer, choose what you want to do right now. Know that like the rest of the tools in your shop, certain printers will be good at certain things. In the future, you will probably gravitate toward having a BK printer, AK Printer, and one set up for fine detail (for things like upper extremity).
Build Volume
We walked through this above, but the first consideration when looking at printers is build volume. We’ll have one printer recommendation for BK sockets and another for AKs.
Our recommendation (that should cover 80%+ of parts):
- For BKs, at least 10” in height and 8” in length and width.
- For AKs, at least 18” in height (preferably more), and 12” in length and width.
Compatible Materials
Knowing which materials a printer can work with is important. If you’re considering working with high-end engineering grade parts that include things like PEEK and PA-CF, you may need to replace your hot end and some other parts. For the majority of our applications (test sockets), any printer will be able to print the materials we’re interested in.
Our recommendation:
For test sockets, we recommend printing with PETG or PCTG. These are both almost identical to the Vivak material that you’re used to. They print easily, with good clarity, high strength and toughness, and grind and heat incredibly well. The PCTG is slightly tougher than the PETG and should give you a bit more strength, but for most applications, you won’t notice the difference.
Buy rolls of filament that are at least 1.5lbs/.7kg, so that you don’t have to swap out rolls of plastic in the middle of a socket print. A test socket will usually take about .3-.6 kg of filament for a transtibial prosthesis. Once you get the hang of printing you may want to put one large 10 kg spool so you can print 20+ sockets without swapping filament.
Where to buy (remember to get 1.75mm filament!)
- Essentium Materials PCTG: http://essentiummaterials.com/product/essentium-pctg/
- Makeshaper PETG:
http://www.makeshaper.com/product/natural-petg-1-75mm/ - Push Plastic PETG:
https://www.pushplastic.com/products/petg-750-grams
Enclosure
Some printers have their build volume enclosed in order to keep dust out and to keep warm air in. Unless you’re planning to have your printer in your shop near your plaster, you’re probably fine using a printer without a full enclosure.
Our recommendation:
No need, unless you’re going to put your printer in a dusty environment. That said, Watch out for drafty area of the room where vent or fan may be over the printer as the movement of air may cause some print inconsistencies.
Nozzle Size
To start, we recommend using a 0.8mm nozzle for the majority of your prints. With a .8mm nozzle you are looking at a 5–7 hour print for a standard transtibial prosthesis depending on wall thickness. If you’re okay with something a little bit lower resolution, you can bump that up to 1.0mm or 1.2mm nozzle for a sub 5 hour print time. For things that are very fine resolution, you can always swap out for another nozzle at 0.4mm, but printing something the size of a BK socket with a 0.4mm nozzle would take well over 20 hours.
Our recommendation:
0.8mm will be your standard, but have a 0.4mm nozzle on hand for fine-resolution prints. Once you get comfortable with the 0.8mm nozzle, test out printing with 1mm or 1.2 mm nozzles.
Our Printer Recommendation
In most cases, we suggest the larger Filament Innovations Printer or the Raise 3d N2 Plus. That said, you cannot go wrong with any of these printers — we’ve included them all because we have first- or second-hand experience with them.
