Fan Kick - Tiny Feature Request

Greetings!

Slic3r pretty much exceeds my wildest dreams, and this is an extremely minor issue, but here it is. My fillament cooling fan will happily run below 100% but it will sit there and twitch until I tap it with my finger, then it's great.

Maybe this isn't a common enough issue to be worth addressing, but it occured to me that anytime there is a period where the fan is going to be run below 100%, you could turn the fan on to 100% for a second or two then drop it down to the actual desired speed.

Whether this is something that gets added or not is cool, just throwing it out there. (Thanks for implementing the Lift Z on layer change!)

This makes a lot of sense. I can happily run a fan at 30% voltage (or PWM), but that isn't enough to start it going.

Would be nice to have the a fan startup time (time to run it 100%) before dropping down to a slower speed. IMO in most cases, it'd probably only need to be about 1/10th of a sec - basically enough to get some momentum into the blades, but that all depends on the fan and so on, so having it configurable is best.

You just need a PWM smoothing circuit, I use a resistor and capacitor.

Something like a 1ohm 1/2watt resistor and 100uF 50V cap.

Its called and RC filter.


Edited 1 time(s). Last edit at 06/16/2012 01:49AM by Sublime.

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I think even with DC fans have a higher starting voltage than the stall voltage.

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I'm pretty sure the RC filter won't help much at all - the issue is as nophead says that you need a higher starting voltage. With the type of brushless dc fans most people use the hall effect sensor crudely tries to detect where the fan blades are, and if it isn't spinning fast enough, and the current isn't enough, it won't have the momentum or the force to get to the next "click". The fan circuitry is really not meant for significantly lower voltages, so this would be a really nice feature (I use a desk fan so not for me). To save slic3r from the crazy amount of variables of skeinforge, just a fan kick tickbox would probably be enough, choosing a value of (say) 1s wouldn't cool anything too much I'd expect, and would be enough.

I believe the best place to solve that would be firmware or even better - as suggested above - electronic circuit.

On the other hand you could use a Slic3r postprocessing script to workaround that specific issue.

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Most of my technical comments should be correct, but is THIS one ?
Anyway, as a rule of thumb, always double check what people write.