Printing spiral springs


With some try and also some error I managed to print spiral springs now, but just barely.

I’m printing the springs laying a their side.

So halfway the print you have a lot of small ‘islands’ which will become the spring coils:

o o o o o o

o o o o o o

This is where the problem starts, suppose I number the islands like this:

6 5 4 3 2 1

7 8 9 10 11 12

problem is that on islands 1 and 12 the printer always prints two layers two layers at the same island, before the first layer has the chance to cool down.

so printing sequence is: 1_2_3_4_5_6_7_8_9_10_11_12_12_11_10_9_8_7_6_5_4_3_2_1_1_2_3_4_5… (notice layers 1 and 12)

ideally it should be: 1_2_3_4_5_6_7_8_9_10_11_12_1_2_3_4_5_6_7_8_9_10_11_12_1_2_3_4_5…

Increasing layer time doesn’t help because the printer only prints more slowly (eg if you set min layer time at 35s, the printer calculates his print speed so one layer takes 35s, without having to stop printing. So islands 1 and 12 keep having two successive layers…

Yes, it is possible to perfect-print working spiral springs without the need for support structure.

Who’s up for the challenge?

In some cases like this I add two objects into the printing layout to be “sacrificial”, one before the first desired item and one after the last. Thus, the “sacrificial” items receive the doubled (and often damaging) “last of this layer then immediate first of the next” extrusion, giving the real desired items the time to cool between layers. The “sacrificial items” can just be extra copies of the “real” objects if they are small enough, or else just simple cubes, etc. to not waste so much filament.