Chris' Punisher 4 L3 build

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Wow! You dodged a bullet there.

Want to know a secret? I brought my minimum diameter rocket back from the pad since my backup electronics weren't arming. As I set it down on the table to do the investigation I found the nuts/washers that hold my electronics bay together right there... on the table... :facepalm:

I've never been so happy to have problem with my electronics.
 
Want to know a secret? I brought my minimum diameter rocket back from the pad since my backup electronics weren't arming. As I set it down on the table to do the investigation I found the nuts/washers that hold my electronics bay together right there... on the table... :facepalm:

I've never been so happy to have problem with my electronics.

You definitely dodged a bullet. I like to pre-prep all my airframes ahead of time to avoid issues like this. It's alot easier to prep in the comfort of your shop with plenty of time and no overriding sense of go fever.
 
You definitely dodged a bullet. I like to pre-prep all my airframes ahead of time to avoid issues like this. It's alot easier to prep in the comfort of your shop with plenty of time and no overriding sense of go fever.

+1

I do the same thing whenever I can, and consider it a "pre-prep." I don't install shear pins/rivets, and obviously no energetics, so everything does need to get opened up at the field. But it is easy to run through the full prep if everything is already in packed and in place.
 
Thanks. It's a Sony FDR-X1000V. It will shoot up to 4k30 or 1080p120 video. At 1080p60 and below it will shoot stabilized video. If you watch the YouTube video you'll notice that the camera seems to move in the rocket. That's the SteadyShot in action.
 
Well, it's been 5.5 months and my booster still hasn't been found. I guess it's a write off. :mad: Yesterday I realized that there are 3 weeks until Dairy Aire. I decided that I needed to get off my butt and get the booster that I bought on BF built.

I came home last night and started working on the motor mount. I attached on of my APE thrust plates with Rocketpoxy. Then I attached the Kevlar recovery harness to the MM with BSI 30 minute epoxy. I machined a new front centering ring with slots for the kelvar recovery harness to pass though. I attached it to the MMT with Rocketpoxy. Motor mount DONE.

Today I installed PEM nuts for the rail buttons. The I epoxied the motor mount into the airframe and one of the fin roots to the motor mount. I'm going to attach one more fin shortly.
 
Sounds good Chris. It's amazing that a year has gone by isn't it?
I picked up some 1" Kevlar strap from Wildman with the intent of bonding it to the motor mount. How much length should I use for this? Should I keep the loop long enough to come well out of the booster or keep it shorter and inside the booster tube?

I finally started building a new project today.. the Frenzy XL. I installed one of your nosecone bulkhead rings in the nosecone coupler with fluorescent red rocketpoxy... my daughter likes that color better than the black pigment. I plan to use Aeropoxy ES6209 for the Kevlar strap bond to the 75mm motor tube, I hope it penetrates the Kevlar weave well.
 
What I like to do with the 1" Kevlar is bring enough out of the tube so I can tie a loop or sew a loop on the end. My idea is if one side of strap breaks or epoxy comes loose the other side may hold long enough to get rocket down safe. Plus I slide a 1" section of tubular nylon over the Kevlar loop just long enough to protect Kevlar from getting cut on the tube edge. Maybe its over kill but it works for me.
 
I glued 8" of the Kevlar to the MMT leaving 2-3" sticking out of the top of the booster. That way the quick links don't hit it.
 
I got all three fins attached at the root this morning. Once that was done I injected the internal fillets with 4g of RocketPoxy in three places on each side of each fin's root. Now I'm working on pulling the external fillets. I'm using ~20g of epoxy per side with a .5" radius.
 
The booster is all done. I just need to prime and paint it. I spent about 15 minutes on each fillet. I usually have trouble shaping the ends, but they came out great this time around.

IMG_4685.jpg
 
I primed the rocket on Wednesday morning and wet sanded it with 600 grit yesterday morning. I just put on my first color coat and got a HUGE wrinkle on one of the fillets. :bang:

I had to open a new set of Rocketpoxy to do the last fillet. I'm not sure if it is the same one that the paint just wrinkled on or not. The Rocketpoxy has been curing for 4-5 days though. You'd think that it was dry by now. The primer has been drying for 48 hours. I'm not sure what the problem is. Oh well, I'll let the paint dry overnight and then try to sand the wrinkles out tomorrow morning.
 
I have a couple weeks until the launch. I should have plenty of time to fix it. I'm not going to put an automotive grade paint job on it this time around though.
 
I picked up an Aerotech M1780 NT for my L3 today. :w:

Eric was telling me about those reloads a few weeks ago... they give a nice punch off the pad and have sweet colored flame to boot. I look forward to your flight. Hope Jacob gets some off-the-pad shots of the New Thunder exhaust plume.
I read that you need to bond the grains into the liner for this load.. else risk CATO, apparently due to grain compression during acceleration.
 
Hmmm, there's nothing in the instructions about grain bonding. According to my sims it will only pull 20.6G. For reference the M1297 pulls ~18G. I could see the motor needing it if it was in a lightweight minimum diameter rocket, but this rocket doesn't fit either of those descriptions.
 
Thanks Tim! I don't mind doing it if AT says I should. I guess I have a project for this weekend.
 
Yea same here. I bought same motor and about 2 weeks later they put out service bulletin.
 
Last weekend I sanded out the wrinkles in the paint and re-primered those areas. I managed to resist the urge to repaint the rocket all week. This morning I used a brand new can of the same paint to repaint the rocket and it went on without a hitch. I sprayed two wet coats on and left it to dry. :w:

Over the weekend I weighed out and built the 4 ejection charges. I also charged the batteries for both altimeters and the camera.
 
Saw your previous L3 attempt last year and wish you a successful flight this year.

Grad Maximilian!

St. Maximilian Kolbe was a Polish rocket scientist who was executed in a death camp in 1941. He's considered the patron saint of rocketry.
 
Apparently I have supremely ticked off the Rocket Gods...

We got the rocket on the pad around 10AM. The rocket boosted nice and straight and then coasted to 14,000'. The drogue deployed perfectly and it fell at 69fps until the main charge went off at 750'. Unfortunately the Main got stuck in the nose cone and didn't deploy. The rocket landed tail first in a plowed field and broke the fillets on two fins. The nose cone also splited along a seam ( it was one of the injection molded plastic cones).

It is a pretty tight squeeze to get the 60" Fruity Chutes Ultra Iris chute into the nose cone but I've had 2 good deployments from this HED setup.

Anyway, I have a brand spanking new filament wound cone sitting in the garage. The fillets can be repaired. All of the other hardware was recovered intact. I may switch this rocket over to a more standard dual deploy setup with the main in the payload bay between the NC and the altimeter bay.

I'm in pretty good spirits. I had a great time at the launch. I'll take another crack at it again soon.



Chris
 
That's a sweet liftoff shot! Sorry to hear about the incident, seems like you've got everything all planned out for next time!


Braden
 
Nice shot off the pad Chris. I'm guessing that the M1780NT didn't let you get to many stills in. That's a nice motor, love the flame.. looks a lot like the Super Thunder's Diamond Line Plume.
 
Apparently I have supremely ticked off the Rocket Gods...

We got the rocket on the pad around 10AM. The rocket boosted nice and straight and then coasted to 14,000'. The drogue deployed perfectly and it fell at 69fps until the main charge went off at 750'. Unfortunately the Main got stuck in the nose cone and didn't deploy. The rocket landed tail first in a plowed field and broke the fillets on two fins. The nose cone also splited along a seam ( it was one of the injection molded plastic cones).

It is a pretty tight squeeze to get the 60" Fruity Chutes Ultra Iris chute into the nose cone but I've had 2 good deployments from this HED setup.

Anyway, I have a brand spanking new filament wound cone sitting in the garage. The fillets can be repaired. All of the other hardware was recovered intact. I may switch this rocket over to a more standard dual deploy setup with the main in the payload bay between the NC and the altimeter bay.

I'm in pretty good spirits. I had a great time at the launch. I'll take another crack at it again soon.



Chris

Great attitude!
 
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