Itty Bitty Double Extruder

[beerdart]

Why not? ...

[clough42]

So in playing with the Geetech one on D6/D11 I found I could just install it shifted two sets of pins to the right towards Aux-1 and now it runs on D4/D5, This also opens up D11 for the servo to connect to so I don't have to do any modding of the expander. Board type 34 works fine with it installed two rows of pins over. I would expect the RRD expander on D4/D5 might be able to be shifted one row to make D11 available to the servo and still have D4 for the fan.

Perfect. That's a lot easier.

[clough42]

Oh...interesting. In that video, it looks like they're using the filament drive to force the hot end down against spring pressure. I think the only issue would be the diameter of the heat block. How big are they?

[beerdart]

Correct it uses filament pressure with a spring return down tube. There unit looks a little long but it might fit. I plan to make a new cold end with retract for my set-up. If anyone has a broken Hex i could look into modifying the cold end.

[Poindexter]

Is there any benefit in having the print fan running during preheat? Thats how my printer was configured during the test prints. Is it meant to reduce oozing?

[clough42]

Is there any benefit in having the print fan running during preheat? Thats how my printer was configured during the test prints. Is it meant to reduce oozing?

I don't run the print fan during preheat.

[clough42]

Correct it uses filament pressure with a spring return down tube. There unit looks a little long but it might fit. I plan to make a new cold end with retract for my set-up. If anyone has a broken Hex i could look into modifying the cold end.

Hey...that looks like it might fit with the right groove mount and a long enough servo probe arm.

[TopJimmyCooks]

It's an intriguing idea but I would need to get more real world reviews. It just seems like Z level repeatability would be tough to get consistent.

[clough42]

It's an intriguing idea but I would need to get more real world reviews. It just seems like Z level repeatability would be tough to get consistent.

Yeah...it is a great idea, but it isn't clear to me if it's adding a lot of value.

If you look at the Stratasys UPring SE Plus (which is a fantastic printer if you have five figures burning a hole in your pocket), it uses a cam system to raise and lower its two nozzles. There's a cam bar extending all the way through the head assembly, sticking out both sides. You slide it back and forth to switch nozzles. While printing, the printer runs the head all the way against the side of the frame to push the bar to one side or the other, then moves the nozzle over a catch bin, extrudes some plastic into the bin and then wipes the nozzle on a metal brush. It does this for every nozzle change, so twice per layer.

This auto raise system doesn't really deal with priming or cleaning the nozzles, so I think at best it just keeps the idle nozzle from dragging across the print and smearing whatever it's oozing onto the print. If it's oozing, though, that extra plastic is still going to get wiped somewhere.

[adamfilip]

can you add something about wiring up Nema 14s the colors are different then the standard steppers from makerfarm