My Robo3D upgrades (Smooth rod bed, z-axis stabilization, direct drive extruder)

Can you post a pic of the bigger bed and rails?

 

Lol i wanna see too

 

http://www.thingiverse.com/thing:386602 Like these?

 

Thats not what i meant. I thought he was gonna print the buggrt version.

 

Peter, here a picture of the bed mount. The bed itself has the same size since I wanted to reuse the stock bed, but the area to print on has increased to 280mm. Even though its not fully heated, I am able to print parts in PLA since it sticks very well on the blue tape. More pictures are available at the link in the first post or the one from Mike Kelly. tonycstech created a remix of my design with an untested version for a even bigger printable area.

 

ok there it is.
one word, WORKS
What i learned was: Craftware does not produce precision prints as CURA does, so i had to print most using CURA code.

thingiverse files updated. I changed fan mounts to be standard instead of having E3D specific or what ever else. Its easier to print E3D fan mount specifically for E3D version instead of reprinting entire bracket.


Here is all my trial and error (well some of it.)

 

I modified the base to be more centered on the carriage.
Now entire assembly is centered.
I also added a 16 pin ribbon cable hole so i could have this:
Notice how i have a guitar string taped to the cable ? It makes it go UP when carriage moves to the right.
Simple and effective.

Just had to shave off the carriage hole about 2-3 mm to the right to allow extruder to go in.
No limit on X, instead i somehow get 232mm.

 

@tonycstech. I really like the ribbon cable. Will you be including a BOM and instructions for it with the extruder?
This might be a noob question but I'm interested in more details of how the guitar string works.

P.s. I've completed you y axis upgrade and will upload my make with details to Thingiverse in the coming days. It's pretty damn good too.

 

what is BOM ?

I am printing a slightly fixed ABS version of the base, making it stronger final print. I will try to give some instructions on a separate topic after i take needed pictures.
String attached to the top of the belt with the electical tape (or what ever tape you want)
Then i slightly bent the tape bending the string at the same time, making it want to go up. It wants to go up and it does when extruder goes to the right
I used 2nd string from the bottom (0.012 inches diameter), it provided just enough tension to lift the belt.
Rest goes thru the hole at the base of the ROBO case as usual, and mounts on the side with a paper clip holding it in place.
See picture below.


I dont know of any male connectors for this 14 pin IDC, mainly because most of the time it connects straight to the circuit board.
What i did was i soldered a pin at the tip of each wire i needed to run thru this cable and connected then in the same patter as they are on the extruder.

At this point i dont know what i need to buy to make it look better so i'll stick with what i have.

 

BOM is Bill Of Materials. The cable bundle is one of the things that annoys me the most so I'm really liking the ribbon idea. But is the wire thick enough to carry the power for the hotend(s) safely, the stock hotend wire is thicker isn't it?

 

It prints, so i guess the answer is yes.
But i do feel that its warm.
Maybe i should get a thicker ribbon cable ?

Or maybe run not 1 line but 2 lines for each nozzle wire, would that make the load cut in half per wire ?

 

Yes, if have spare wires, simple use them in parallel (more than two is also possible). I would advise to do it, if the cable gets warm, there is a risk of damage to the printer or the environment.

 

Its 100c degrees rated standard 28AWG IDC cable. Its no where near that temperature after running for 2 hrs. I think its safe.
Its slightly warmer then me, enough that i can feel it. Perhaps 40c-50c max.
Bed at 70 feels very hot compare to the cable.

There are 2 extra lines left unused, so i can utilize them to see if anything changes.
Will report back sometime later after print is finished.

 

Another finding about the temperature of the motor.
It should be cooled with fan.
Internal heat is transferred to the pulley. Its OK with ABS, but with PLA and heat bed ON about 70c or above enough heat is created to soften the PLA and cause it to slip/grind/ruin the print.

Thats that.

 

Anything to report regarding the IDC cable getting warm with regards to the hotend?
I was thinking the 2 hotend heater wires could be taped to the top of the IDC cable so the hotend has dedicated thicker wires, could use silicon wiring for extra flexibility.

 

Nop works no problem.
I gotta think of something better then string pulling the cable up. cant realy come up with anything.
AM thinking plastic soda bottle sheet of plastic. Cut it as a belt size and its already curled. Should work but cant try, gotta run to work.
Might try when get back.

Printer works great, no issues at all.

 

Tony, In addition to getting warm that 28AWG wire will drop about a volt from the 12V drive depending on the cable length. That will reduce the power of your 40W hot end by 3 or 4 watts.

 

Is it possible to get thicker gauge IDC cables? Or is my idea of dedicated hotend wires along with the IDC cable for everything else the better/only other option?
I really like the idea of using an IDC cable, it's better/neater than a cable chain.

 

You are probably not going to find a thicker IDC cable. Doubling or tripling up the signal and ground is a good solution.

 

Does anyone know value for MK7 gear ?
MK8 starts to slip due to unknown to me factor so i want to try MK7 (larger gear less motor rotation perhaps less motor heat)
Thanks !