Hm…it is so simple it just may work…
I will put mk8 grub screws on both motors
Not powerful enough.
Hm…i dont know… didnt tested motors. They were 4 usd thsts why i bought them
Using two regular Nema 16 motors would work. Maybe a 3D printed panel and you are good. The added weight is a concern. Two powerful Nema 14s may do it. Could be a neat low cost option to our gear hear or the bond tech
For Bowden tubes, the weight wouldn’t be a concern.
That i am tinkering about,to get a cheaper alternative,both options are to expensive for me right now. Motors are tiny and ultra cheap,whole cold end with screws under 15 usd. But we will se if this works…
How will you manage adjusting the tension or pressure on the filament?
Tension could be adjusted by making one of the motors mount to a plate and then spring load that to the rest of the assembly.
Fun! I experimented with this idea previously, and @Walter_Hsiao dubbed it the fostruder : https://www.thingiverse.com/thing:1088212 which was an interesting way of tensioning. I had a design that pivoted one motor on a 5mm bolt ( https://github.com/elliotf/two-motor-extruder ) , and my later design uses a printed live hinge: https://github.com/elliotf/foster-parametric-extruder/blob/double-motor-drive/fostruder-e.stl
One thought that I had was twin PG35L motors or something small and geared for more steps/torque.
One gotcha is that normal MK8 hobbed pulleys have a groove that is too deep for 1.75mm filament… I don’t want to hijack this thread, but let me know if you’d like to talk about it!
What is the ounces per inch holding torque on one of those? Add that up and compare it to a nema 17.
Maybe offset the gears by half a tooth?
Rotate one motor 45 degrees and you might be able to reach all the screws to mount the second motor.
You could make one motor adjustable but it’s better to set the distance in the design. We use pinions that have a machines groove for the filament. That way the pinions lock together and always turn at the same rate
Hmmm…or the tensioning and the access to the screws could all be done with a spinning mount for one of the motors.
you could just have slotted screw holes. so you can slide the motor left n right a bit to adjust it. then you could just brute force the filament though kinda like on a bondtech. i doubt you need it tension. but bigger motors will help.
One waterjet aluminum plate might do it. Might be worth playing a it.
well, i can only laser cut alu 
i think i will PRINT this one
still need to remove pressed timing pulleys from motors.
I’ve been running a version of this design very reliably. It is a direct drive effector mounted unit on a delta homebrew. It is currently running at 85mm/sec, 1000-1500 acceleration very accurately with almost no visible ringing - have never had a feed failure. Haven’t pushed it any harder as yet since I value quality over speed. However, there are some tricky aspects to the design. I’m currently designing and building Mark2 with the aim of reducing mass substantially.
@Robert_Bilbrey do you have the design/pictures up anywhere?