Ceramic Nozzle 4 ur extruder

Ceramic Nozzle 4 ur extruder
Have an new idea of how to make a Ceramic Nozzle for use with the high heat of the extruder. I’m looking for a trade(s) & to work on this project.

In order to work you would need to design and make a plastic Nozzle mould in several parts. Remember this would need to be a reverse of the finished product. So for example one part of the mould would be a solid nozzle hole because that would be open in the finished product.
My suggestion would be to make the output size smaller than anything now avaiable ie (be the first on the block to have it). If the design works you have plastic smaller than now possible.

Note one problem I forsee is regarding the threading to the barrel as Ceramic is more fragile. Contact me and we can work on several ideas that might be best.

What do I wish in trade?
The test Ceramic material is pricy. I'd also be interested in a set of Mendel parts run off for me. If I can get a few interested maybe supply me with other parts to complete a build and continue the research on this ceramic nozzle project.

Visit the Prober Blog

Hi Prober,

... or build your nozzles without bore and drill it later in any desired diameter - i have a 50-Watt-laser with 1070nm wavelength and spot diamter down to 10 microns, so it should be possible to 'drill' holes down to 0.02 mm in diameter.

Only one problem left - for smaller holes you need much more force/pressure, so my feeling with the actual design limits the practical diameters to 0.2mm minimum.

Another point for testing is the poor thermal conductivity of ceramics - here it could be a problem generating enough heat close enough to drive the plastic molten through the nozzle ...

Viktor

Want to give it a go Viktor? Would enjoy working with you on this.

VDX Wrote:
-------------------------------------------------------
> Hi Prober,
>
> ... or build your nozzles without bore and drill
> it later in any desired diameter - i have a
> 50-Watt-laser with 1070nm wavelength and spot
> diamter down to 10 microns, so it should be
> possible to 'drill' holes down to 0.02 mm in
> diameter.
>
I agree, and this would be great for testing. Was thinking in the long term on the project so that users could build their own nozzles.


> Only one problem left - for smaller holes you need
> much more force/pressure, so my feeling with the
> actual design limits the practical diameters to
> 0.2mm minimum.
>
Think I might have a fix for dealing with pressure. Visit the Prober Blog & let me know your thinking.


> Another point for testing is the poor thermal
> conductivity of ceramics - here it could be a
> problem generating enough heat close enough to
> drive the plastic molten through the nozzle ...
>
> Viktor

Maybe we are thinking the same thing and I’ve said it the wrong way? My idea is to “insulate” the heat wihin the nozzle and or barrel. Have a real nice Blog entry in mind to write on this when time permits.

The more heat we can keep inside, and not dump into the air the more efficient the heat transfer to the “feed material” will be.

Prober

Hi Prober,

i've actually probed with different materials and powders - white or translucent materials are tricky with 1070nm wavelength ... most energy went through or is reflected diffuse ... here a CO2-laser with tenfold wavelength should work much better.

Anyway, i tried with white MACOR - it's melting, but didn't evaporate for drilling ... the same with clear glass-spheres or the white/translucent mixture from eccospheres (hollow glass-spheres) and waterglass.

I have a glas-solder powder white in colour, what's a bit different - when melting, it turns brown/black, so the absorption magnifies instantly by decades and it's burning/fuming/evaporating.

So for 'serious tooling' i have to select the materials for higher absorption, like the black rock-spheres or maybe grey concrete-dust or dark coloured plastic-powders.

The other point to adress is adjusting the energy with PWM and controlling from the Arduino - actually i'm probing 'manually' with CW ... awaiting the complete documentation and some aditional parts/options.

And with the glass-solder i received some fuming - could be toxic, so i'll pause other tests until venting/exhausting is ready.

And last i need shielding with inert gas, as the tests with iron-spheres and -dust and thin steel-sheets show high potential, but in air it's oxidizing/burning ...

---
Another point for isolating heat: - read through the posts with "waterglass" - i mixed some pastes from 50 micron big hollow glass-spheres and waterglass.

This stuff is drying to a lightweight white solid behaving like styrofoam and good heat-isolating, and can withstand temperatures until 500 centigrades!

It's not strong enough for the extruder-body, but can work as isolation when used as coating ...

Viktor

Edited 1 time(s). Last edit at 11/25/2009 03:54PM by VDX.

Lot's of good material in your last post for me to ponder

Quote
And with the glass-solder i received some fuming - could be toxic, so i'll pause other tests until venting/exhausting is ready.

I'm a little surprised in all the designs regarding "toxins" Some type of carbon air cleaner should be part of any encosed design.

In the mean time I intend to use an air cleaner in my build room if I can get someone to build me the starter Mendel parts (hint,hint).

Hi Prober,

with FFM/FDM you shouldn't receive toxic fumes/vapours unless you overheat

When burning materials with a laser you'll get high toxic fumes what can be vented and neutralized with an activated charcoal filter, but you have some recondensing and saturation of the powder with fumes and cracking products, so you should ventilate the building area and let the fused parts degassing for some hours (or even some days!).

Without venting i can only probe with ceramics, rockspheres or other nonorganic materials, as here the products shouldn't be carcinogenic.

The tests with the glass-solder were a bit different - some of the ingredients are reactive, others are basic toxins as lead compounds or organic additives intended to evaporate completely, when heated.

And when testing with materials of unknown receipe, then i want to ensure there is nothing hazardous, as my children comes often in my basement for rummaging

Viktor