[AR] Re: Vacuum processing of solid propellant
- From: <mark.spiegl@xxxxxxxxx>
- To: <arocket@xxxxxxxxxxxxx>
- Date: Tue, 10 Sep 2019 17:02:36 -0500
I am wayy behind on my email so this msg is a delayed response:
On Behalf Of Troy Prideaux wrote:
If I vaguely recall (I could be mistaken) it was Mark Spiegl (?) who 1st
mentioned this process here about maybe 15 odd years ago. If I recall he
For me, centrifugal casting worked extremely well. I was able to get
consistency and measured densities much better than I ever achieved with vacuum
processing. I suspect Anthony Cesaroni is 100% correct that tossing propellant
in a bucket and pulling a vacuum doesn't do much. It needs to be processed
under vacuum.
If I were going to make a Bates grain, even 6" or 8", I would probably use
centrifugal casting. You can buy a wood lathe for a few hundred dollars, and
the centrifuge parts are trivial to make.
When the centrifuge stage is done, a clear line of demarcation exists between
liquids and solids. Just bore-out the useless gummy core. My measured density
was very close to theoretical.
On Behalf Of Doug Jones wrote:
Perhaps you could put the mix in a funnel and extrude it through a small
nozzle into the motor case in a vacuum chamber? With a rubber ball
floating on the surface to block the funnel as it goes empty.
The funnel method did not work for me. I think you need a pourable propellant.
My stuff would "glop" in the funnel and then "glop" in chunks into the lower
chamber. Measured density was poor. Again.. I think exposure time to the vacuum
isn't long enough to do anything.
--MCS--
Other related posts: