Friends of Amateur Rocketry in California offers a hands-on course on
making APCP engines. I have not done it, but if I was getting into
APCP I'd strongly consider signing up for it. They can be reached
through FB or the last email came from
mark@xxxxxxxxxxxxxxxxxxxxxxxxxxxx
I expect people on here have contacts for the Mojave Test Area, you
could see both sites in a weekend. (they're in walking distance of
each other, a few miles southwest of the middle of nowhere)
Here's the text from this month's email:
--------------------------Announcing APCP Motor
Classes---------------------------
We are happy to announce more APCP motor classes given by John Newman.
Duration: 3-Days on FAR Saturdays
Class Size: 2 to 5 People
Cost: $300.00
Includes the following that you get to keep:
• 38-millimeter motor hardware
• Flash Drive with formulas in Excel Spreadsheets
You should bring the following:
• Lunch
• Laptop computer
• Flyable rocket having a 38-mm motor mount
Class will supply:
• Motor chemicals
• Motor casting tubes
• Equipment for mixing and propellant preparation
Planned activities:
• Lectures
• Make APCP motors
• Static fire your motor
• Launch your motor
A reference book you should buy:
• Experimental Composite Propellant,
An introduction to properties and preparation of composite propellant;
design, construction, testing, characteristics of small rocket motors.
Author: Terry W. McCreary, Ph.D.
(One-Source) Aerocon Systems for $59.00
Major Lecture Subjects
Excel Spreadsheets
• K/N ratio
• Erosive burn
• Fuel formulation
Lathe operation
• Cut, drill, and face fuel
• Cut liner
• Drill nozzle
Static test
• Pressure
• K/N
• Regression rate
• Delay timing
• Data reduction
Propellant Mixing
• PBAN
• HTPB R45
• Pourable
• Hand packable
On Thu, Jan 30, 2020 at 12:10 PM Wyatt Harris <wjh3828@xxxxxxxxx> wrote:
Hi everyone,
I've been subscribed to AROCKET off an on for the last ~20 years, and I
believe this is my first post (I may have sent one when I followed this forum
back in high school, but I can't remember).
To provide a bit of an intro about myself, for those that care, or at least
to show that I'm not coming at this totally out of the blue:
I started building rocket motors in middle school and continued into high
school (early 2000's). They were almost all KNSB motors (thank you for your
website Richard Nakka!), with the exception of a large LOX/hybrid that I
built with a propulsion engineer from Raytheon, and launched at BALLS 2004.
I went on to get a BS in Astronautical Engineering, where as a senior I was
chief engineer for a boosted dart rocket project that was launched at WSMR in
2009. Following college I got a MS in Mechanical Engineering, did some other
stuff for a few years, and am presently 1.5 years into a 3 year PhD program
in Astronautical Engineering (not researching anything propulsion related
however; I'm actually examining a GNC topic for spacecraft RPO).
To the subject of this email: I recently got back into building small rocket
motors as a hobby. I've made a few small KNSB motors, though I'm more
interested now in moving on to APCP. I have the APCP/HTPB kit from Firefox.
For the time being, I intend to build and test motors with <50g of propellant.
I'm reaching out to the forum with the hope that this might be a good place
to get some advice on working with APCP (especially regarding safety, common
pitfalls and best practices). I've got and have read through Experimental
Composite Propellant, Plastic Resin Bonded Fuel Systems (Firefox book), the
CP technologies book (doesn't seem very helpful for APCP though), and I also
have Burnsim. I intend to proceed following the procedures outlined in the
first two books as closely as possible.
If this is the right place to ask, I suspect I'll have plenty of questions
moving forward, but to pose a couple to start:
(1) My main concern right now is proceeding safely, so any practical advice
out there regarding safe production of small APCP (<300g) batches? My initial
plan is to use an open garage with PPE including nitrile gloves, goggles and
VOC respirator. I've taken a look at the SDS's for the chemicals involved, it
seems that IPDI is is the nastiest component? The SDS for this makes it sound
very toxic.. how concerned should I be about this for the small batches I'm
making? Any concerns/things I should know about other chemicals such as
AP/HTPB/EHA/tepanol? I'm not planning to do any crazy propellant formulations
(exotic oxidizers/metals) at this point.
(2) I opened up the teponal (HX-878) from the kit and noted that it is
*extremely* viscous (challenging to remove any with a tongue depressor).
Since it's been a while since I bought the Firefox kit, wondering if this is
normal, or has it gone bad?
Thanks for reading the long email. Thank you in advance for any advice!
-Wyatt
