Re: sport rocket staging timer

On Tue, 29 Apr 2008 22:19:56 GMT, Rich Grise <rich@xxxxxxxxxxx> wrote:

On Tue, 29 Apr 2008 08:20:12 +0000, Smaug Ichorfang wrote:

Some friends would like to build a down-sized model of a two-stage sounding
rocket. I'm trying to come up with a design for a timer to ignite the
second stage. The timer should be triggered by a "g" switch which marks
first stage ignition, and time out after (an adjustable) 1.5-2 seconds,
just after the first stage burns out. Commercial designs are available for
around $90. I only need to build ONE of these andd don't have the
programmer so a pic or BASIC STAMP are out. Any ideas or schematics for an
analog or simple digital timer for this application?

When I was a kid, Estes rocket motors were available with an "after-charge",
which is basically a hole at the top of the motor that shoots hot gas
into the nozzle of the second stage right at burn-out. So, no electronics,
batteries, squibs, none of that schtuff was needed.

The idea of a 1.5-2 second timer with batteries and squib and all of that
just seems ludicrous on a rocket where the first stage only lasts 1.5-2
seconds.

Good Luck!
Rich


Long ago I made a 3 stage rocket with those types of motors.
Never found the rocket afterward. :(
There was a note inside..'If found please call......'
Never got a call :(

And that was the last of my rocketery...
Electronics looked better as a hobby.
Breadboards don't take off and disappear. :P


D from BC
British Columbia
Canada
.

Relevant Pages

  • Re: Orbiter shape.
    ... By an orbiter I mean a second stage of a ... I would be inclined to think more in terms of rocket first, ... Do not compromise the rocket design if you can ... Vertical landing on a soft ...
    (sci.space.policy)
  • Re: sport rocket staging timer
    ... I'm trying to come up with a design for a timer to ignite the ... When I was a kid, Estes rocket motors were available with an "after-charge", ... into the nozzle of the second stage right at burn-out. ...
    (sci.electronics.design)
  • Re: are all rocket completed seal?
    ... This rocket crashed because the shock cord failed, ... timer and servo driver. ... Here the electronics that control the servo is very basic: a timer ...
    (rec.models.rockets)
  • Re: sport rocket staging timer
    ... sounding rocket. ... I'm trying to come up with a design for a timer to ... that shoots hot gas into the nozzle of the second stage right at ... also,hybrid motors using Nitrous oxide as the oxidizer must use electronic- ...
    (sci.electronics.design)
  • Re: THE^ DDI.T ME. THA(`NG HYTRAN KO MA`N THA(`NG TRIE^T DDU+O+.C DDI.T LO^`N LAURA BUSH KHO^NG ??
    ... Chu+?i DDau the^ Ma` ka c'o.i cho+? ... Washington cho bie^ t la` chuye^ n tha(m cu?a Anh ... Trie^ t kho^ng fa?i la` State Visit la` ai?? ... Ka c'Anh Vietzan Za` bi. ...
    (soc.culture.vietnamese)