Chris' Punisher 4 L3 build

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Wow. I'd like to request that your next rocket be transparent so that we can admire all of the cool metal work from the outside!

Yes, he does great work.

Mine got its last fillets today, effectively finishing the bottom half. One step closer to flight!
 
I got back to work last night. I did one last session with the spot putty. This morning I wet sanded all the putty down with 320 and then wet sanded the entire rocket with 400. I put a couple light coats of primer over the putty spots and then wet sanded with 600.

It's as smooth to the touch as a baby's butt. The fillets still aren't perfect, but I think I'm done with body work. It's a rocket and it's going to get scratched up on the first flight anyway, right?
 
I laid down 2 coats of Duplicolor Chevy Orange and one coat of clear. It came out pretty well but I have a couple runs to sand out.

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Looking great Chris, when is the maiden flight?
Motor? Camera?
Please share your details when u get time, ejection charges, etc.
 
Nick,

I'm shooting for April. My daughter has cheer until mid March. I want to use something that will put it low enough that I can watch both deployments, so maybe a 2 grain 54. I don't have my Möbius camera installed yet, but I have started thinking about how I'd like to mount it.


Chris
 
Chris
The 2 grain 54mm CTI Skid would be a great motor for it. I fly that motor a lot. Nice and loud and the sparks are fun to see.
 
Nick,

I want to use something that will put it low enough that I can watch both deployments, so maybe a 2 grain 54.

Chris

FYI:

I wanted to do same thing.....see all events to validate my choices.
My Punisher 4 maiden flight was today. AT J-275 W [2 grain 54..852 case]

2486 ft. Sims were showing 3100-3400 on this, & several other 2 grains, both CTI and AT

ready flight weight w/o motor 9lbs. 3oz.

2 gr.BP on appogee
1.2 in main.......I tested OK with 1 gr but made them 1.2 "to be sure".

Everything worked perfect. I will do more detailed report, on my set-up later. Just thought this might help validate some of your choices.
 
Nick,

I'm shooting for April. My daughter has cheer until mid March. I want to use something that will put it low enough that I can watch both deployments, so maybe a 2 grain 54. I don't have my Möbius camera installed yet, but I have started thinking about how I'd like to mount it.


Chris

Thanks for taking a break from your own Punisher to work on mine!

I will bring my camera pod to lunch next week.
 
Thanks for the data Jim. I haven't purchased my recovery gear yet so I haven't started working on deployment charges yet.

Are you using shear pins? If so haw many and what size? I'm using three nylon rivets at both joints. They seem to be between a 4-40 and 6-32 screw in strength. I was using roughly 50 PSI to shear a pair of them in my 3" Saab. I'm pretty sure I'm going to need bigger charges than you used.
 
That'd be fun. Good to see you lurking here. Hopefully I'll get to a launch fairly soon so I can say hello.

Wow. I'd like to request that your next rocket be transparent so that we can admire all of the cool metal work from the outside!
 
I finished the paint today. It came out pretty well. I need to order some vinyl to finish it up.

I also ordered my recovery gear from FruityChutes yesterday. It should be ready to fly by the end of March.

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I got confirmation from Gene that my recovery system should be ready by Friday. I ordered an IFC-60 with a Chute Liner and shock cords.

Here's what's left:
1. Install recovery gear.
2. Add ballast to the nose.
3. Deployment charge testing.
4. Decals.
5. Finish up sims, L3 proposal.
 
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I picked up my recovery gear from Gene at lunch today. When I got home I weighed everything. The main chute, parachute liner, quick links and NC shock cords weigh 12.5oz. The entire bundle takes up about 8" of the nose cone. :cool:

I updated my Open Rocket file with the accurate weights for the recovery gear. My TAPs say that I need a minimum of 1.5 calibers of stability for my certification flight. To get there I need to add 50 oz. of ballast.

I measured out the lead shot and then poured it into the nose cone. I needed to add 4" to the eyebolt so I added a section of all thread with a threaded coupler and used red Locktite to ensure that it would never come apart. I used some Proline epoxy between the nose and tip and let that dry. Then I threaded the eyebolt into the tip. Once that was dry I started working on the ballast.

I've been searching for a ratio of epoxy to lead shot for a while and I found an answer today.
1. Randomly arranged spheres will take up 64% of a given volume.
2. Cubic inches times .554 will give you fluid ounces.

I poured my ballast into a 54mm tube and found that it took up about 10.6 cubic inches. (2.125" ID x 3" depth)

10.6 x 36% = 3.83 cubic inches.
3.83 x .554 = 2.12 fluid ounces.

I mixed up 2.5 fluid ounces of 30 minute epoxy and added the shot to it. The shot was evenly covered and still pourable. Once it settled into the nose cone I cleaned up the shoulder and parachute bay with denatured alcohol. The epoxy came up to the bottom of the eye. Perfect.

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Today I made a G10 plate to move the Telemetrum right up against the bulkhead. This should eliminate any transmission issues with the antenna being bisected by the aluminum bulkhead.

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Here's what's left:
1. Install recovery gear. ( I need a 4 more quick links and a 3' harness for the nose cone)
2. Deployment charge testing.
3. Decals.

The sims are done and have been submitted. My TAP looked at the rocket last weekend and was happy with the build. I just need to finalize my proposal and submit it.

I ordered my M1101 on Friday. It looks like I won't be able to fly before May 15th, so I guess we're going to maiden it at Dairy Aire. I'm seriously thinking that it's just going to fly on the cert motor. We'll see.
 
Chris just a FYI on an issue I had by mounting the GPS close to wall of airframe.
This happened with a Telamega & the Missleworks. It may or may not become one for you.

The first 3 times this happened, lock was fine at table for warm up. When placed on rail once[and tower 2x] could not get lock.
Move rocket out or off tower/rail..... lock.....back on/in ....lost lock. I was receiving from radio, but no satellites on screen. Drove me nuts!

Finally dawned on me.....GPS antenna was situated directly in front of rail [and 1 rail in tower]. There must have been some blockage of satellite signal or Faraday type thing going on. After figuring this out, I simply rotated my bay so GPS antenna was either facing between rails in tower......or faced away from single rail.
Everything went fine after that.

I now make sure when mounting GPS it's oriented so no longer any issues & mark externally where it's located.
Hoping you have no problem, but if you do......it could be this "gotcha".
Good Luck with your L-3!


Ps: the manual being finalized for the Missile Works GPS makes mention of this issue on mounting page, so other don't run into it.
 
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Here's what's left:
1. Install recovery gear. ( I need a 4 more quick links and a 3' harness for the nose cone)
2. Deployment charge testing.
3. Decals.

The sims are done and have been submitted. My TAP looked at the rocket last weekend and was happy with the build. I just need to finalize my proposal and submit it.

I ordered my M1101 on Friday. It looks like I won't be able to fly before May 15th, so I guess we're going to maiden it at Dairy Aire. I'm seriously thinking that it's just going to fly on the cert motor. We'll see.

Go for the autograph, and spend the test flight money on the post-cert celebration. :cheers:
 
Jim,

I ran into a similar problem with my 54mm rocket. It would lock out of the tower but not in it. I wound up turning on the altimeter about a foot above the top of the tower and then lowering the rocket once it got a GPS lock.

On this rocket the Telemetrum is on the opposite side from the buttons. I moved it against the skin so the bulkheads would shadow the GPS antenna a little as possible. I've got a decal to mark the GPS antenna's location coming too.

These GPS antennas only receive from the top. The bottom is a ground plane. Your Faraday cage comment is pretty accurate. GPS uses signals above 1Ghz so the signals are blocked pretty easily.
 
Can't wait to see the decals you are going to use. They really add to the look of a rocket. If I were a kit builder all my kits would come with at least a decal of the kits name.
 
Me too! I haven't put any on the last couple rockets I've built, but since this is my L3 I decided to spare no expense.

Can't wait to see the decals you are going to use. They really add to the look of a rocket. If I were a kit builder all my kits would come with at least a decal of the kits name.
 
I received the decals yesterday. There are a couple missing but they will be here soon. I really like the JayHawk scheme, since it's a pseudo scale scheme I thought I'd acknowledge my past. I grew up near George and Edwards AFB and served 4 years in the USAF.

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Just for Jim:
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What's with this "Max propellant" business?! "Max Propellant" should be "whatever will fit, and then some". It's called a Punisher, not a "I'm afraid to fly this thing" :)

awesome decals btw.
 
I looked at what would fit and then found out how much propellant was in the reload. I think I used an 75mm 6 grain M840.
 
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