Direct Drive with ribbon cable

Credits for the idea and initial design goes to Stargrove1

All files are downloaded from my thingiverse page
There are two version of this upgrade.
Standard. No modification required. Print parts, Assemble and you-re done.
NOTE: Standard setup does not have ribbon cable system. Old wiring is not effected. See my thingiverse for latest version that would implement the ribbon cable feature.
Reversed. Needs to cut/shave off the carriage to allow repositioning of the hot end and moving X motor pulleys back as far as possible to prevent belt touching the motor (see picture below) There should be plenty of room to do that.


Things to buy:
1 meter long 14 pin (or 14 way) ribbon cable with 1 female connector on each end (2 connectors)
OPTIONAL: You can buy arduino male 2pin and 4pin jumpers and wire them to motor, fans etc to simplify connection into female adapter.
http://www.ebay.com/itm/10pcs-30cm-...t=LH_DefaultDomain_0&var=&hash=item338d5a84ff
MK8 Drive Gear Filament Pulley $9.00
5x10x4mm Ball Bearing - MR105 2TS $5.00
PTFE tube (need about 10mm piece. You may have it laying around)
Take drill bit and drill PTFE tube from the top to create a slight taper inward. It will help to guide filament into the center.

Things to find: Cookie plastic container or large plastic jar that will allow you to cut curved piece of slice matching the ribbon cable width, so it would support it underneath as it travels left to right. (See example below)

Things reused from old extruder assembly:
All screws and springs are used from old extruder.
2 springs combine into 1 making one strong spring (if 1 does not provide not enough tension).
2 long screws and nuts are used to attach hot end clamp.

Firmware:
Look into file "Configuration.h" and find the line below
define DEFAULT_AXIS_STEPS_PER_UNIT {80,80,2267.72,723.38}
Change 723.38 to 145.51

Wires:
Wires are connected below the printer and attached which ever way you want.
What ever pattern you decide to connect then at the bottom, at the top its going to be the same.
Probe wires by connecting fan first to make sure that correct unit is responding.

E3D and Fan mounts:
E3D hotend has standard J-Head so it should fit.
I designed my own tight fit fan mount that is mounted on the right for standard and on the left for reverse version. E3D fan mount tightens against the hotend, so dont go crazy if fan fail to spin or makes noise, loosen up the screws, you wen too tight.
There are also standard fan m0unts that are required to print. They serve as spacers. You can put few washes on your bolts if you dont want to print fan mounts. Just make sure that screws dont go beyond nuts cutting into the motor.

 

How necessary is it to cut the extra bit out of the x carriage (shaded in red) for the reverse design?

 

Cut only if you install reversed one (motor facing you).
Otherwise it wont fit.

 

Guess I can always print a new x carriage with the hole in the right place instead

 

There is no problem cutting the hole.
It does not effect the functionality of the carriage. Old parts and standard upgrade will fit no matter what.
This is only to allow reversed designed to work.
No risk at all.

 

latest update.

 

Does anybody know the steps value for MK7 gear ?
I want to try MK7 because MK8 seem to be slipping or the motor has gone bad/weaker. I notice the filament not laid when it retracts and primes (same value both ways) Did not have this problem before, its started to develop lately and is not getting any better unless i slow down to 30mm/s or less.
Thanks !

 

I think It does not effect the functionality of the carriage. Old parts and standard upgrade will fit no matter what. This is only to allow reversed designed to work.