howdy Whacko, tnx for your input.
I have actually built the fab@home electronics setup and got it working on my machine.
While they have done an excelent job on their project the build speeds are far too slow for what I want,
the max speed I got was 5mm per second. But really the thing that put me off fab@home was the gui
interface,I never felt I had much control, I much prefer using Gcode and Mach3.
A while back I bought a nice fine airbrush and yep of course it`s already been fully stripped down
I have the needle valve and seat ready and waiting should I decide to go down that route.
At the moment I`m trying to stick with the nozzle arrangement I have, The holder I made
for the Nozzle valve also incorporates 3 power resistors mounted in a triangular array which
provide me with a heated up air gap (between 3 to 5 deg C) as close to the nozzle end as possible
to prevent nozzle freeze.
Being a bit impatient I could`nt wait the 2 weeks or so to get the smaller .05 mm nozzle so I stuck
a bit of epoxy resin to the bottom of my .25mm nozzle I had and ground a very fine point on the
end of a drill bit, I was able to gently push this thru the back of the nozzle till it just poked thru the epoxy
and have managed to make a .035mm dia hole (measured on a shadowgraph).
So armed with this I thought great I have a much smaller dia flow it`s got to help.
Hey man the flow runs well, at full pressure I can create a water jet the thickness of a hair and shoot this
for about 200mm before the jet breaks up. In practice I want the nozzle between 3 and 5mm from the build layer,
and reduce the pressure as much as possible.
In principle the machine is working, I must just match the flow and freeze speeds to the axis speeds, and still try sort
out this problem of flow blobs during axis pauses.
I think that problem is my hardware, I cannot get more G`s out of my motors without them stalling all over the place.
And so I cannot get the table speeds I need. Perhaps the Stepmaster Driver I`m using is`nt up to the job, or maybe
just bigger and faster stepper motors would be the solution.
If I hold the nozzle in my hand and literally sweep it quickly over a frozen plate, I get a lovely thin and blob free frozen line,
just the job.........
So thats where I am ATM.
Regarding my final goal.
As a mold toolmaker I always wondered about making prototypes a lot cheaper and faster. So I came up with this Ice idea.
Our company manufactures big pump assemblies and all too often bad designing causes problems on final assembly, brackets and
castings being in the way of pipework for example.
What I`d like to do is make scaled models of each of the assembly components, these can be put together as a miniature mock-up
of a proposed build and discussed while still in the design stages of a customers order.
So I want to create molds made from Ice, and my intention is to pour/inject pourable plastic into the cavity, let the plastic harden and melt the ice away to leave the 3D component.
I tell you it`s a pleasure working with water, there are no expensive consumables like those found in other Rapid Prototype systems.
here`s a few pics of the nozzle arrangement, the flow and a crappy blobby effort
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