MR Friskie

I have a rocket that I built a while back, it’s one of my favorites.

It was named it “Mr. Friskie’s cluster of death”
It’s a 3” diameter rocket with 7 each 24mm motor mounts. Originally designed to fly 3E class and 4 D class rocket motors.

Here is the story of how it earned its name.

It started with a challenge. I like building rockets with multiple motors, most notably one named “Cluster Duck”. But thats another story.

I found that you can fit 7 24mm motor mount tubes into a 3″ airframe. So I thought I would give it a go.

I later found that the real challenge was in the launching, not the building.

You see when you ignite a single rocket motor you only have one little motor light. If it doesn’t go off then you try again, no problem.

However with two rocket motors it gets real important that both motors fire at the same time. If not you end up with a rocket that will launch erratically and most likely prescribe loops in the sky, with an unpredictable landing, usually a total loss.

I speak from experience.
Look for the story of the infamous Cluster Duck, and The Windsor Wizard in the near future.

You double your chance of failure with two motors, what I wanted to do, was launch a rocket with 7 motors. You do the math.

I had to come up with a way to ignite 7 black powder motors at the same time with out adding complexity to the design. Then I heard of something called “Flash in the Pan ignition” It’s simply some flammable mixture in a pan (Black Powder), you light it and all the motors will light in the ensuing fireball. I wanted to go one further to make sure all motors lit, so I added some Elmer’s glue to some water, and painted the mixture into each nozzle. Then while wet poured in some 4F black powder.

Now what do I use for a pan? I found that a Friskies cat food can fit perfectly.

So at the next launch I set up the rocket “As yet un-named” on the launch pad. I taped the Friskies can to the launch rod. Then I poured in about 5 grams of 3F black powder and added one igniter. Went back to the LCO.
My friend John came over to watch it launch. I asked him what he thought of the rocket and the flash in the pan, he said “oh Id do that if I were you” (wink wink nudge nudge if you know what I mean) Poof, Wooooshhh Yes! Every motor lit, perfect flight to about 1200’, I told John I was thinking of naming it cluster of doom. He suggested Mr.Friskiers Cluster of Death. So there it is.
Mr Friskie
Who was I to change something like that?

John just has a way of making a name stick.
Another time I will tell you about Elvis and Martha.


One thought on “MR Friskie

  1. caveblogem says:

    Is this a common method of launching clusters, or an original envention that came out of PF Labs? Either way, its a nice hack.

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