What did you do rocket wise today?

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Knuckledragger

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Sanded the V2 and will shoot another coat of primer tomorrow. Painted the Swift upscale with Rustoleum Fluorescent Orange; paint dries and sands like the pastels my sister used in art class, powdery. Just shot the second coat of poly and set aside to bake in the shed for a couple of days. Will start cutting the masking tape tonight for the V2 camo
 

prfesser

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Glued four of the six fins on the Interceptor E. I have 30 min epoxy and prefer to wait at least 2-3 hours before gluing the next fin (don't want the first one to shift).
 

o1d_dude

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Worked a bit more on the Cherokee-H baffle and rigged up a "compression fitting" to hold the body tube snug against the external-built motor mount which is now installed with epoxy on the forward motor ring. The middle ring will be epoxied from the rear and the fins and body tube will be filleted. When all that's done, the rear centering ring goes in followed by the motor retainer.

Very much looking forward to boosting this candle on an H268R in the fall if the "lung kudzu" eases up.

I like red motors.
 

tsmith1315

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This isn't the normal doing something rocket-wise but it's pivotal to me...

Last night I made great progress in sparking my 12th-grade son's interest in rocketry (will be very helpful in my starting to fly HPR again). I casually left open an old spreadsheet that I was using to scale down the 3-round Javelin III flight outlined in an old issue of HPR. Something wasn't adding up, and I had put question marks there to remind myself the numbers needed to be reviewed. That's bait for a math geek. A little later he said he saw I had question marks on a spreadsheet, and asked me what I was trying to do.
I explained what it was and found an opening in the discussion to get to grain geometry, brought out a G75 grain and showed him the slot, how it would change during burn, how that would influence chamber pressure, and BAM! Fish on! After a brief back and forth over that, we went to other grain geometries, looked at some thrust curves, and he declared the velocity/altitude curves generated by the old wRASP simulator to be "beautiful". After finding a couple of launch videos to illustrate, he asked if we would be able to "get in" to a launch. I said not only will we get in, we'll be flying a rocket, too!

Whew! The last time I tried flying, he was about 5. The noise, the people, the non-routine situation was too much for an Asperger's child. It just didn't work, he was miserable. I knew my HPR days were done for a while. Fingers are crossed that we'll be in Nashville in November!
 

o1d_dude

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This isn't the normal doing something rocket-wise but it's pivotal to me...

Last night I made great progress in sparking my 12th-grade son's interest in rocketry (will be very helpful in my starting to fly HPR again). I casually left open an old spreadsheet that I was using to scale down the 3-round Javelin III flight outlined in an old issue of HPR. Something wasn't adding up, and I had put question marks there to remind myself the numbers needed to be reviewed. That's bait for a math geek. A little later he said he saw I had question marks on a spreadsheet, and asked me what I was trying to do.
I explained what it was and found an opening in the discussion to get to grain geometry, brought out a G75 grain and showed him the slot, how it would change during burn, how that would influence chamber pressure, and BAM! Fish on! After a brief back and forth over that, we went to other grain geometries, looked at some thrust curves, and he declared the velocity/altitude curves generated by the old wRASP simulator to be "beautiful". After finding a couple of launch videos to illustrate, he asked if we would be able to "get in" to a launch. I said not only will we get in, we'll be flying a rocket, too!

Whew! The last time I tried flying, he was about 5. The noise, the people, the non-routine situation was too much for an Asperger's child. It just didn't work, he was miserable. I knew my HPR days were done for a while. Fingers are crossed that we'll be in Nashville in November!
You’re a good dad, Tim.
 

jqavins

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(Well done, Dad, and yes, hooking in the next generation is very much doing something rocketwise.)

Well, my friends, it's official: I suck.

My second day of launching went like this.
  • First up, my Red Nova with an oversized engine. The CG is shifted back, but the RSO and I both believed it was OK. A heads up launch, at my own suggestion. Unstable, did some skywriting, and came down undamaged.
  • I went to load a plane old D12 in the Red Nova. A little bit of edge swelling jammed in the MMT, and I stove the whole motor mount in.
  • I prepped my Solar Flare (modded for an 18 mm sustainer engine) with a C6-0 and A8-3. The RSO was happy and I got my pad assignment. All seemed well until I tried to place it on the rod and discovered that I'd never attached the launch lug.
  • Last was my Grand Daddy (a modded 29 mm Big Daddy) on a G80-4. The nose cone broke free of the airframe at ejection, the 'chute did not deploy, and neither part was found.
For the whole weekend that makes six up with only two successful, and one prepped but aborted.

I suck.
 

tsmith1315

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We've all been there Joe!

No launch lugs! 😆 I remember having to CA a set of lugs in place on the field in the same situation!!!

Glad to see you didn't lose a G motor case along with your Grand Daddy. The next launch will be better.
 

Nytrunner

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Well, my friends, it's official: I suck.
If you suck, so does Jim Jarvis, Steve Shannon, and every other rocketeer (myself included) who've had a bad day.

There'll be better days at the field. This one was depressing, but i believe you'll have better luck in the future
 

JimJarvis50

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If you suck, so does Jim Jarvis, Steve Shannon, and every other rocketeer (myself included) who've had a bad day.

There'll be better days at the field. This one was depressing, but i believe you'll have better luck in the future
Although I would point out that my Big Daddy on a G80 worked, well mostly....

I was using a chute release, but also a small drogue. I have found that without something to slow the rocket a little, it can fall too fast with a weighted cone and the chute won't open. I think the drogue was just a bit too big, though, so the rocket was not falling fast enough for the larger main to open (but it was falling fast enough to crack a fin). Need a Goldilocks drogue. Just about fixed.

Jim

Big Daddy.jpg
 

les

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I went for a walk.....

With the COVID and work at home, I stopped getting exercise walking to meeting, labs, etc - and started gaining weight (over 10 pounds).

I finally decided I needed to take time and start walking. And my walks got longer. And I decided to try different routes for variety. One new route is fairly long, so I don't do it often. I did notice a large field and thought "that would be great for flying". The other day when walking I saw a gentleman mowing the field. I flagged him down and started a conversation:
Me: How are you doing? Is this your land?
Him: Yes
Me: This may be a bit bold, but as a hobby I build and fly model rockets. I was wondering if I may be able to occasionally use your field for a launch
Him: Sure - just make sure you clean up any mess and don't fly when its too dry
Me: THANK YOU!

IMG_5781.jpg
 

rklapp

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I went for a walk.....

With the COVID and work at home, I stopped getting exercise walking to meeting, labs, etc - and started gaining weight (over 10 pounds).

I finally decided I needed to take time and start walking. And my walks got longer. And I decided to try different routes for variety. One new route is fairly long, so I don't do it often. I did notice a large field and thought "that would be great for flying". The other day when walking I saw a gentleman mowing the field. I flagged him down and started a conversation:
Me: How are you doing? Is this your land?
Him: Yes
Me: This may be a bit bold, but as a hobby I build and fly model rockets. I was wondering if I may be able to occasionally use your field for a launch
Him: Sure - just make sure you clean up any mess and don't fly when its too dry
Me: THANK YOU!

View attachment 424293
I don't know. Could be a trap. Lure you in with a mowed field. Can't be too careful these days. Those trees on the right look hungry. (just kidding)
 

o1d_dude

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Added more fillets to my Cherokee fin can. I’ve added on to my medieval fin can jig. These photos are of the original configuration which worked pretty well.

The idea was to provide external force to the middle motor tube centering ring which went in to body dry because the forward centering ring swept the area clean on the way in.

The first set of fillets bonded the body tube to the middle centering ring.

I then added three more braces and aligned them along the fins, one on each side. Tomorrow I the fin/body tube fillets will go in.

This is my first externally built motor mount slid into a slotted body tube so I’m sort of making it up as I go along. My progress thus far leads me to believe this is a “good thing”.
 

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jqavins

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What works nicely for LP is probably adaptable here.
  1. Use a long stick to apply a ring of glue where the forward centering ring will go.
  2. Insert the motor mount assembly part way and canted.
  3. Use the stick to apply a ring of glue where the aft ring will go.
  4. Insert the motor mount assembly all the way.
1594643040304.png
 

neil_w

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What works nicely for LP is probably adaptable here.
  1. Use a long stick to apply a ring of glue where the forward centering ring will go.
  2. Insert the motor mount assembly part way and canted.
  3. Use the stick to apply a ring of glue where the aft ring will go.
  4. Insert the motor mount assembly all the way
This is exactly what I do most of the time. One caveat: in step three, it is hard to avoid getting some glue on the motor mount tube. If the fins will be TTW, you have to be careful, lest you end up with glue bumps blocking the fin root from setting properly.
 
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Greg Furtman

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What works nicely for LP is probably adaptable here.
  1. Use a long stick to apply a ring of glue where the forward centering ring will go.
  2. Insert the motor mount assembly part way and canted.
  3. Use the stick to apply a ring of glue where the aft ring will go.
  4. Insert the motor mount assembly all the way.
View attachment 424313
I do this too but I mark the stick with a sharpie so I know how far in it should go before spreading the glue.
 

rharshberger

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This is exactly what I do most of the time. One caveat: in step three, it is hard to avoid getting some glue on the motor mount tube. If the fins will be TTW, you have to be careful, lest you end up with glue bumps blocking the fin root from setting properly.
Same here, it works.
 
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