Are commercial composite propellants unsuitable for this? A 14" grain
of Blue Thunder(TM) propellant, just under an inch in diameter, cast in
cardboard tubing, is $12. RCS has a dozen other propellants, slow
(Black Jack), fast (Warp-9), sparky (Metalstorm) if BT isn't suitable.
They also have a few propellants in smaller diameters, plus phenolic
tubing insulators to fit the cardboard tube if that is desirable. Not
as much fun as making your own, but reproducible and inexpensive.
https://www.rocketmotorparts.com/Blue_Thunder__Propellant_Grains/cat1577810_1952803.aspx
Best -- Terry
On 10/29/2020 1:10 PM, ken mason wrote:
Remove the nozzle first to extend burn time at atmospheric pressure.--
I made my own custom grains formulated with things that burn vigorously in an oxygen atmosphere. Burn time ~ 10 sec plus embed a thermocouple 1/8" from the end of the grain to verify the ignitor is burning before opening your prop valves.
K
On Thu, Oct 29, 2020 at 11:03 AM Gram Nylen <dmarc-noreply@xxxxxxxxxxxxx <mailto:dmarc-noreply@xxxxxxxxxxxxx>> wrote:
This is just an inexperienced shower thought, but could one use a
small Estes motor in some kind of orthogonal mount flush to the
chamber wall as a liquid engine igniter?
On Oct 29, 2020, at 10:58 AM, Doug Jones <rocketplumber@xxxxxxxxx
<mailto:rocketplumber@xxxxxxxxx>> wrote:
I second the recommendation for a spark torch igniter, which will
also serve as a team building exercise that improves confidence.
Once you have a reliable ignition system your team can move on to
the next level.
On Thu, Oct 29, 2020, 10:55 AM roxanna Mason
<rocketmaster.ken@xxxxxxxxx <mailto:rocketmaster.ken@xxxxxxxxx>>
wrote:
From personal hands-on experience with TEA it's not ,my first
choice for an ignition system. TEB costs an order of
magnitude more,i.e. $20 vs $200/gallon as of 20 years ago. It
depends on what you're igniting, how many times,how often,
ground vs flight,etc.. I prefer a pyro for one shot or
limited cycles and a so called 'torch' ignitor for multiple
and repeatable ignitions.
K
On Thu, Oct 29, 2020 at 4:04 AM Dr Edw Jones
<Rocket.Pioneer@xxxxxxxxx <mailto:Rocket.Pioneer@xxxxxxxxx>>
wrote:
Any guidelines for storage and handling of small amounts
of these tetraethyl compounds?
Any recommended purveyors of small amounts?
Thanks, Edward Jones