I bought some on amazon and don't like them. I found some at [www.dglass3d.com] but I think they're too expensive. I found more at [micron3dp.com] but they are also pretty expensive. Can anyone suggest a good source that is not too expensive?

If you need a lot of these, it would be cheaper to produce a small series yourself in a local metal-shop.
Just have to come up with your own tailormade drawings.
-Olaf

Hmmm that is something to consider.

I was hoping for the whole assembled dual extruder though with the thermistor, the motors, and all that already built in.

I've been using a Bulldog XL with an E3D v6 hot end to print with ABS for 6 months and haven't had to clear a single jam from either in that time.

I think the key to reliability in a 1.75mm extruder is to get one that has a gear box to multiply the motor's torque. The high torque allows you to set pinch wheel tension very high and that allows high downward force on the filament without stripping it. I used to have problems with direct drive extruders chewing divots in the filament and losing grip until I went with the BullDog XL.

A pair of BullDogs would be easy to mount along side each other. I made a detailed drawing of it here: https://www.youmagine.com/designs/bulldog-xl-extruder-model-with-dimensions

Here's a drawing that shows the way I mounted it on my printer:



The bracket that the extruder sits on is made from a piece of an aluminum equipment rack. The extruder is mounted with just 2 screws. If you were going to mount two of them side by side you probably want to reassemble one as a mirror image of the other to put the levers that release pinchwheel tension on the outside.

Edited 3 time(s). Last edit at 06/18/2015 07:31AM by the_digital_dentist.

I have 2 bulldog lites and the weight on the print head carriage is ridiculous. I have uploaded to thingverse a duel carriage which has the bulldogs mounted on the frame

Edited 1 time(s). Last edit at 06/18/2015 01:27PM by GRAYWOLF.