What's a good extruder for a Delta ?

I recently finished building my Delta printer and am extremely satisfied with all of it but the extruder setup, I can't run at any decent speeds because it seems the the extruder or settings can't keep enough filament on the print, currently I'm using a Nema 17 Stepper with 76 oz in. coupled with an EzStruder with 1.75mm filament, someone please suggest to me what direction to go on this, I'm starting to lose hope . . .

Thanks,
JMF

This one can push at least 25 mm³/s if it has proper driving gear for Φ1.75mm filament and springs. One spring should produce force in the range of 20-30 N when pressed. Tested with ABS at 230°C. I did not try to push more than 25 mm³/s because the print quality starts to degrade at about 130 mm/s. The springs and the driving gear on the pictures are not the right ones.
[forums.reprap.org]
[forums.reprap.org]

Edit: ... and that is with 0.5 mm nozzle.

Edited 2 time(s). Last edit at 01/12/2015 08:39AM by hercek.

My vote is for the airtripper

I think Airtripper is probably the best choice if your stepper and the driver are strong enough so that you do not need it geared down. But my experience is that the common stuff needs about 2:1 gearing. That is unfortunate.

jmf's 54 N*cm should be enough if he can achieve them. But the specified numbers are typically for 48V and maximum driving current which may be easily even 2.7A. One cannot achieve that with the common stepper drivers we use
The result is that the specified stepper torque is almost useless for us. One needs to lookup speed - torque charts for the voltages and the driving currents we use which is probably something like 1.5A at 12V for most of us. But hardly any manufacturer specifies that since 1.5A/12V is badly underrated.

So jmf, if you really can achieve 54 N*cm then select airtripper.

Edited 1 time(s). Last edit at 01/12/2015 02:50PM by hercek.

I use this:

[www.thingiverse.com]

It's marvellous. My NEMA 17s were way underpowered for using a direct drive setup. Now it can pump out filament all day long and not miss a beat.

Thanks iira !!