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Finished Chapter 4 of Make:HPR. Each chapter has very new material that I've never seen before. This one goes over the L1 certification papers and even gives some tips that look time-saving. Then it goes through building an AeroTech H128W-M, something I have never done before. After an introduction to fuel types ("White Lightning," "Blue Thunder," etc.) it then walks through building a Cesaroni H163-14A and its corresponding fuel types ("Classic," "Imax," "Skidmark," etc.). All of this was new material for me. I probably already said this, but I'm extremely glad that I'm reading about these things before trying them. This seems like almost a different world from LPR.
 
Speaking of L1- after many dormant years, I can call myself an active HPR flier again!

Got my L1 at Turkey & GRITS this morning using the same rocket and motor that I used for L1 back in 1995. My trusty old Expediter with an H238T for a quick up and down as the range closed due to impending weather.

That same rocket was used for L2 on a J275 a year later and was last flown many years ago at Freedom Launch in Orangeburg when a hard landing wrinkled the airframe just above the fins.
 
Speaking of L1- after many dormant years, I can call myself an active HPR flier again!

Got my L1 at Turkey & GRITS this morning using the same rocket and motor that I used for L1 back in 1995. My trusty old Expediter with an H238T for a quick up and down as the range closed due to impending weather.

That same rocket was used for L2 on a J275 a year later and was last flown many years ago at Freedom Launch in Orangeburg when a hard landing wrinkled the airframe just above the fins.
Welcome back!
 
After an introduction to fuel types ("White Lightning," "Blue Thunder," etc.) it then walks through building a Cesaroni H163-14A and its corresponding fuel types ("Classic," "Imax," "Skidmark," etc.).
Now and then I have a way of detecting misunderstandings. And sometimes I'm all wet.

The above makes me suspect that maybe you got the impression that a given motor, like the H163, can comes in a variety of propellent types. Not so. The CTI H163 is a White Thunder load. Other 29 mm 3 grain loads, of other propellants, have other characteristics (except there are two Blue Streaks; go figure). Check out this CTI web page. The story is the same with AT, and all laid out in their catalog (web site).

And if I was all wet and you already knew all that, please forgive the unnecessary lecture.
 
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I just ordered enough PSII body tubes, couplers, nose cones, and 29mm engine tubes from Estes to build two, maybe three rockets. Getting ready for 2021 :)

-Bob
 
Had an 'ah-ha' moment earlier this evening involving my Estes 2231 Fin Alignment guide...

I've been struggling with a recent build, a 1/10 scale Iris from the Semroc kit, using the aforementioned Estes product to attach the fins to the body tube. Fins were not ending up perpendicular to the body tube. I thought it was that the Estes guide (most likely the plates to which the fins are attached) that was a problem, but it turns out it was mostly on me.

What I was not taking into account is that the fins are tapered in thickness from root to tip, the sides are not parallel. As a result while the plates are indeed perpendicular to the body tube, the fins were not because of the taper.

Resolved the problem by placing a shim between the fin and the guide plate in order to 'square' the fin to the body tube. Lesson learned...
 
Placed a few orders for rocket electronics.

I ordered 2 flight sketch minis, and a order with Eggtimer: proton, quark, quantum, apogee, trs, gps reg/mini, wifi switches reg and mini.

Looking forward to sitting down this winter and soldering them up, then how do I test all 8 altimeters and 2 gps modules... custom sled for the 1/4 scale Viking 7 possibly.

Arming 9 altimeters and 2 gps units at the away cell sounds like a lot of work. I plan to build a vacuum chamber with the ability to power on the device and test up to 6 channels at once with lights and a known good altimeter along with my mechanical and digital manometer.

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~John
 
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Looking forward to sitting down this winter and soldering them up, then how do I test all 8 altimeters and 2 gps modules... custom sled for the 1/4 scale Viking 7 possibly.

~John
@GalantVR41062 I bought a small Sterilite airtight, gasketed storage container and drilled a small hole in the top. I have a small vacuum pump and I put a suction cup fitting (came with my MightyVac hand vacuum pump I use on my cars). I arm the Eggtimer, put it in the box & close the latches, fire up the vacuum pump and hold the suction pump on the top directly over the hole. it works great!
 
@GalantVR41062 I bought a small Sterilite airtight, gasketed storage container and drilled a small hole in the top. I have a small vacuum pump and I put a suction cup fitting (came with my MightyVac hand vacuum pump I use on my cars). I arm the Eggtimer, put it in the box & close the latches, fire up the vacuum pump and hold the suction pump on the top directly over the hole. it works great!
Great idea. I might give this one a go. I have a MightyVac. Just have to keep the brake fluid off the electronics...
 
Now and then I have a way of detecting misunderstandings. And sometimes I'm all wet.

The above makes me suspect that maybe you got the impression that a given motor, like the H163, can comes in a variety of propellent types. Not so. The CTI H163 is a White Thunder load. Other 29 mm 3 grain loads, of other propellants, have other characteristics (except there are two Blue Streaks; go figure). Check out this CTI web page. The story is the same with AT, and all laid out in their catalog (web site).

And if I was all wet and you already knew all that, please forgive the unnecessary lecture.

Honestly, I don't even know enough to even misunderstand. This is all new to me and I come in with zero knowledge, so it's possible that I related something in a confusing manner. I'm still learning for sure. But thanks for clarifying.
 
Started my new project. Fun fact about this is I had originally bought one of these when I was in junior high. A family friend had given me a built andromeda kit that I flew on a C6-5. So, my younger self thought well that didn't go very high on a C6-5 and I have some left..... imagine my surprise. My younger eyes did manage to spot the chute, and I hopped on my bike and recovered my rocket several blocks into the city. It landed right in the middle of someone's back yard. For what these cost today I won't be flying on C's.......well I can't guarantee that!
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I have had my new 3D printer making fin alignment jigs. The initial use will be at my son's 12th birthday party. He will have a couple friends over to build rockets in the evening, and Kansas-winds-permitting launch in the morning.
Nice jigs, and great idea for a party! What rockets are they going to build?
 
Finally finished... Almost a year in the making. I've had this one built, painted and flown for a while but never finished the decals. This was going to be a quick resto job of an old Bertha that was left for dead. When I got it the motor mount had been torn out the rear and it had a couple of broken fins. I removed the remaining fins, sanded them and the body tube down, cleaned out the inside of the tube and started reconstruction. I was able to reuse 3 of the 4 fins, the body tube and the nose cone.

Since I had to make a motor mount I decided to step things up. The main body tube received a full length coupler that stops about 3/4 from the top. A 24mm motor mount was built using heavy wall tubing and plywood rings. Due to the 24mm motor I didn't see the need for a stuffer tube. Next a 300# Kevlar leader is attached to the top of the upper ring and about 10ft of 1/4" elastic was attached. The base of the Bertha nose cone was chopped off and a bulk head was epoxied in with a screw eye.

The rocket was then painted with Krylon Hot Pepper Red and Black. It has flown in this condition on a C11-3, D12-5 and E20-7. Due to the extra weight the C11 makes this a nice small park flier while the D's still put it up around 700ft. We stuck an altimeter in it for the E20 flight and saw 1442 reading but that was at ejection not apogee.

Finally got a chance to paint the last color and do the decals. Painted one fin Krylon Dove Gray and cut my own decals.

First Pic is from the online ad.

Second is mid-way through the resto.

Last is the finished product. Bertha.jpgIMG_8313.jpgIMG_9283.jpg
 
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Finally finished... Almost a year in the making. I've had this one built, painted and flown for a while but never finished the decals. This was going to be a quick resto job of an old Bertha that was left for dead. When I got it the motor mount had been torn out the rear and it had a couple of broken fins. I removed the remaining fins, sanded them and the body tube down, cleaned out the inside of the tube and started reconstruction. I was able to reuse 3 of the 4 fins, the body tube and the nose cone.

Since I had to make a motor mount I decided to step things up. The main body tube received a full length coupler that stops about 3/4 from the top. A 24mm motor mount was built using heavy wall tubing and plywood rings. Due to the 24mm motor I didn't see the need for a stuffer tube. Next a 300# Kevlar leader is attached to the top of the upper ring and about 10ft of 1/4" elastic was attached. The base of the Bertha nose cone was chopped off and a bulk head was epoxied in with a screw eye.

The rocket was then painted with Krylon Hot Pepper Red and Black. It has flown in this condition on a C11-3, D12-5 and E20-7. Due to the extra weight the C11 makes this a nice small park flier while the D's still put it up around 700ft. We stuck an altimeter in it for the E20 flight and saw 1442 reading but that was at ejection not apogee.

Finally got a chance to paint the last color and do the decals. Painted one fin Krylon Dove Gray and cut my own decals.

First Pic is from the online ad.

Second is mid-way through the resto.

Last is the finished product.
Wow...seeing the BB through its stages of completion, I was sledgehammered by the finished product. Looks fantastic!
 
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I made some really thin centering rings to mount a 29mm motor mount tube inside a 38mm coupler for an OddRoc that I am building
I think these are the smallest centering rings I have ever made. About .090 thick made from plywood
 
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