- Can you afford the time? The downsides of printing in 3D is similar to that of laser cutting. A small 6cm snowflake on a laser cutter might only take 2 minutes in acrylic but double the size and it takes four times as long. With 3D printing, double the size and it takes eight times as long because there is eight times as much volume compared to the original. So a small part which takes 6 minutes and is a great demo, becomes a 48 minute wait. If you have a whole class wanting to have their work made, that's a lot of time to commit.
- Bigger things look better and have better definition. If you print a boat in 6 minutes, its going to be a pretty tiny (2cm long) horizontally stripy boat as the layers are a fixed height. Double the size to 4cm and you get better detail. Double it again and the layer lines are lot less noticeable and you can start putting in finer detail, but that takes time to print
- You have to fiddle. With a laser cutter, once set up you can throw material on the bed and provided you dont do anything daft, it will work every time regardless of shape. Cut lines do not interfere with each other.
With a 3D printer every first print is effectively a draft. My boat design (search ajbooker on thingiverse.com) has a raised front because the printer builds up a thicker layer due to flow of material. This fouls the next layer and makes the print rough at that point. I redesign the boat to avoid this but then I have to print it again to check it works. The software I check the design with only tells me it is printable, not the outcome quality. - When things go wrong, they take a while to put right. I accidentally left the extruder head heater on (easy to do as it doesn't have a command to automatically shut down after so many minutes) overnight. It took me a day and the purchase of acetone (nail varnish remover) boiling water ina saucepan and a 0.4mm drill (not a common part) to unclog it. In a workshop under time pressure it would be easy to use what's available and damage the nozzle
- All those marvellous things you see, take forever to print. That cut skull that you can make 4" high? Better put aside a couple of days for a good quality print and £10 of materials. Overall they look great but large parts are a logistical nightmare but you HAVE to print them big to get the detail or mechanism working properly
- Heat, Height, Habitat. Thee ambient heat will affect how well your prints work. In a cool room you might get different results to in a hot one. You have to not knock it while its printing and any feed problems will result in issues
- There will always be a better printer out there. I spent £320 plus Vat on my kit. £500 + Vat and it would print faster and bigger. £2500 plus Vat and it would print faster again with 3 colours or materials. Educational machines have to earn their stripes by being in use for long periods of time, your printer WILL be an antique in a year, let alone three years
So should the above put you off buying one? NO, but look before you leap!
