Jester's 10" FAT MAN build thread!

[Jester]

This is one way to use dual deployment on a short rocket. One drawback is the nosecone has to be hollow without a bulkhead.

 

[ThirstyBarbarian]

The FATMAN has an extra long motor mount, and just above the installed motor is where the main chute ejection charge is placed. The wires for this charge go thru a hole in the motor mount tube to the eBay. Above this charge is a piston which separates the main ejection charge from the main chute, which is installed in the motor mount tube last. Tape is put over the top of the motor mount tube to secure the main in place. So, the rocket goes up, the altimeter sets off the first charge at apogee, removing the nosecone, and deploying the drogue. After the separated rocket falls to the desired altitude, the altimeter fires the main charge and the piston pushes the main chute thru the taped end of the motor mount tube. I hope I explained it well.

Thanks. That’s pretty clear. Are the drogue and main on separate chute harnesses attached to the rocket body? It seems like they would have to be.

 

[Jester]

Yes, 2 shock chords. 9/16 X 20ft for the drogue, and 1 inch x 10 ft for the main. Both attach to the booster.

 

[StreuB1]

Updates!?!?!?!

 

[Jester]

Due to the record heat, drought and burn bans which pretty much equals launch bans here in Texas, I've been putting off working on the FATMAN until today. Finished up the hatch installation.

 

[Hobie1dog]

12 fasteners? wow

 

[cwbullet]

very nice.

 

[Jester]

Almost ready! I hope to fly it next month on a K700 or a 3 grain 75mm.

 

[Hobie1dog]

what paint did you use? or describe the process for us, thanks.

 

[StreuB1]

That looks absolutely amazing!!!

 

[Jester]

Sure thing, first thing was sanding sealer on the plywood fins. Then automotive urethane primer on the complete rocket. Then came the glazing putty on the grooves, blemishes and over the fin fillets. Lots and lots of sanding, then another 2 coats of automotive primer and guide coat. One final sanding to remove guide coat and bring on the PPG polyeurathane. This is the biggest I've built, and took alot of prep time.

 

[StreuB1]

That thing is going to rock on the K700!

 

[Jester]

Empty weight is just over 20 lbs. Here's the glazing putties I use. Nitro Stan shrinks more and needs more coats than the other.

 

[Jester]

Final touches complete, hope to fly this weekend!

 

[Rocket86]

It looks fantastic, great work!

 

[Hobie1dog]

Final touches complete, hope to fly this weekend!View attachment 555905

can you get video for us
?

 

[Jester]

can you get video for us
?

can you get video for us
?

gonna try!

 

[Tractionengines]

Final touches complete, hope to fly this weekend!

VERY NICE LOOKING ROCKET. Looking forward to the flight report

 

[Jester]

 

[DAllen]

gonna try!

 

[Jester]

Maiden flight on Saturday at Tripoli Houston launch. It flew on a K700W to 2800 feet. Rock solid flight, with dual deployment. Main came out a couple hundred feet early. Small zipper damage , probably from heavy nosecone. Sorry to say, due to technical difficultied, I don't have onboard video.

 

[Jester]

 

[Jester]

 

[BrettN]

Awesome flight! Glad I was there to see it

 

[Hobie1dog]

K700 for the win

 

[Jester]

View attachment Fatman TNT_0.mp4

 

[Jester]

K780 redline to 2400 feet!

 

[BABAR]

Nice fin alignment.

I count less than 360 degree of roll for the entire boost!

 

[Jester]

Fatman at Airfest 29 on the L1256 super white lightning! Went to 4364 feet!
View attachment Fatman short_0.mp4

 

[BABAR]

Another great flight! Outstanding fin alignment and beveling, less than 360 degrees of roll for the whole ascent!