Comments on RepRap: Blog: Mk2a RepRap Polymer Extruder Head

Pencil idea is brilliant!Instead of the wire shuto...

2006-07-26T12:39:04.156+01:00

Pencil idea is brilliant!

Instead of the wire shutoff, why not a nice stiff pencil lead of exactly the right diameter made from very-high-temperature-resisting, low-friction, graphite?

Not strong, I admit. But then not subject to lateral stress if the design is right.

Now - how can we use the pencil clutch mechanism to make the valve work?

Preventing the wire from bending is going to be an...

2006-07-25T21:53:02.460+01:00

Preventing the wire from bending is going to be an interesting proposition :)

Vik :v)

I was actually thinking of the same idea -- using ...

2006-07-25T21:06:41.003+01:00

I was actually thinking of the same idea -- using a mechanical pencil tip for the extruder nozzle.

I was thinking of grinding it down to reduce flow resistance. I was also thinking a wire pushed into it from behind would make a reasonable on/off switch -- used in combination with an air compressor (another great idea.)

The nut is actually a carefully shaped item, with ...

2006-07-25T20:08:18.096+01:00

The nut is actually a carefully shaped item, with as shallow a narrow bit as I can possibly manage. I've posted full details here:

http://reprapdoc.voodoo.co.nz/bin/view/Main/InterchangeableNozzleMk2

Vik :v)

Vik: That new extruder really looks great!Reiuki:...

2006-07-25T16:37:32.773+01:00

Vik: That new extruder really looks great!

Reiuki: Wow! That's quite a nice little dodge for getting a good extruder tip. I hope you don't mind if I borrow it. :-D

For interchangable nozzles, I found that sliced br...

2006-07-25T12:44:30.256+01:00

For interchangable nozzles, I found that sliced brass nuts with metal tips from pens and mechanical pencils works well. they solder right onto the end (it appears from the image that you have done similar)

Got 3mm and a .7mm tips that way with minimal effort.