Thursday, 2 September 2010

Reprap build Notes: Part 5. Belts, Wiring and the Extruder.

The Belt Runners on the X and Z axis seemed somewhat ineffective. I was not happy that the M5 large washers I had were only slightly bigger then the bearing.
The M8 Washers I have are 0.75 x the thickness of the M4 washers.
So from the end I have:

M4 Screw | M5 LG Washer |  2x M4 washer. | 1 X M8 Washer | Bearing M4 Washer

The M8 Washers spin on the M4 washers and are approx 2 mm larger than the Bearing.

Extruder Manufacture and Assembly: (Adrians)

Brass Nozzle.

The Rod came from the arm off an old Ball Valve which was 7mm dia. (many people have said that M6 is to small and fragile) 
I ran an M7 x1 die down the rod to put a thread on it.

To make the Nozzle on a lathe:
I faced the end off, centered it, and drilled it 28 mm deep at 3 mm then ran a 3.5 mm drill down to 30 mm deep. 
Use the scale on the tail Stock to get the correct depth.
The drills were all flatted off for drilling brass.
I then parted it off and turned it round.
Center drilled it and put in the 0.5 mm hole before putting the 45 deg angle on the end.
I left the hole recessed by about 0.25 mm.

PTFE Insulator.

I turned that on a Lathe from 20 mm dia rod.
Faced it off and drilled it through with the small hole.
Turned the end down to 16 mm and used the parting tool to put 2 X 2 mm deep groves in. That should give the glue plenty to get hold of.
I parted it off then drilled the large hole 1.5 mm under size then tapped it with a sharp tap to 7 mm to suite my Nozzles.

2 further nozzles and PTFE insulators were made to suite the 1.7 mm filament I have. They were drilled to 2 mm with 0.5 mm in the end of the Nozzle.

Extruder Assembly:

I didn’t have the correct length screws to assemble the extruder so bought some M4 studding and Thread Locked nuts on 1 end.
The large cog is assembled as per the instructions but with NyLoc nuts.

I held the Brass Nozzle in a drill chuck and screwed on the PTFE with some Plumbers tape to provide a good seal.

The Ni Chrome Wire I have is Insulated. 
I wound that on the threads of the M7 Nozzle. The 28 cm required to get 6 ohms is the perfic length for the M7 nozzle.
1 Winding then back to the top.
The Nozzle was covered in Kapton tape and the Thermister installed.

I used Brass Tube to make the crimps and insulated them with silicon sleeving.

The wiring: ( Still work in progress )

Power Supply.

That was made from an old PC Power Supply. See the instructions on the wiki.
I added several big red LED’s so you can see if it’s on.

Need to add a BIG “Time to Panic” button !

Electrical headers and Wiring:

Most of the connectors were provided by the Power supply.

The 4 Pin PCB headers got salvaged from old floppy drives.

Ribbon Cables are old IDE and SCSI Drive cables split down.
10 way IDC Headers are from the Serial Connections on old PC’s.
10 way IDC Header sockets were salvaged from old Motherboards.

Other connectors are from various bits of old PC parts.

1 comment:

  1. Kavaata Valves - Needle Valve used for precise control of flow. They are available is Carbon Steel and Stainless Steel in 0.5", 3/4" and 1" sizes in India.