AMRAAM 4 has arrived!!!

Onebadhawk
the rocketry show
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We had talked about this once before I believe as far as pressure relief goes; Drill one hole at each pressure location per their instructions. Placing a hole in front of the piston does not cause a problem and it will allow you to slip on the nosecone and tail with ease, yet still seperate upon ejection. You don't need a hole behind the piston.

Drilling three 1/8" holes in the altimeter area may not be addressed in the instructions. It is recomended by the altimeter manufacturer, who provides calculations for volume and recommends 3 holes...

Carl
 
After the SAR was a failure. All I could do was go home and sulk. So, while I was sulking, I finished glassing the canards. This time, I mixed epoxy for one joint at a time. That worked out alot better. Tonight I will try pouring the fillets to finish up the canards.

Tired, but still having fun and learning too... :)
 
At this point, I'm still playing with epoxy :)

The fillets of the canards were finished. Although I messed up two of them so I will have to be doing some serious sanding. Anyway, the canards are done.

I also glassed the inside airframe outside the motor mount. This was easier than I thought, but I think the outside will still need to be glassed just to be safe. The motor mount portion was sealed with the rear most centering ring. Although, I forgot to take pictures... Crud...

Tonight I shall start on glassing and filleting the fin sections.

Still having fun...
 
You are flying on the build of this model! Great job so far and I am still having fun reading these posts.

Now, for a small suggestion. I noticed you used glass strips for the canard fins, which should be ok. On the tail section though, I recommend you glass more of each fin and the body tube section in between the lower fins.

Here is why:

The lower section is heavy by itself
Due to the weight, a hard landing could and has cracked the body tube in the fin area
Encasing this area in glass doesn't effect the performance
It strengthens the area so it can handle the stress of both launch and landing
It is easy to do

Here is how:

Cut a piece of glass cloth that extends forward from the fins about 1/2 - 1" and past the rear end of the body tube about 1/2"
Cut the SINGLE PIECE of cloth wide enough to glass from just below the first angle on the upper part of the fin (about 1 1/2" up the fin from the tube) and run across the middle of the body tube.
The SINGLE piece will run down the fin to the joint where it meets the tube...across the body tube...and up the other fin the same distance.
I sent you a drawing once on this, so follow it
Do <b>one epoxy mix</b> for each set of fin sides and body tube area
DO NOT heat your epoxy...mix it at room temperature
Use 30 minute epoxy if you have it, otherwise 15 minute will do
Use the method desribed in the "Tips" section for squeging the epoxy
You will need a steel ruler and a business card or body filler squegee
Let it set before doing the next section
Four sections and the area is done
Watch for drips and clean immediately with alcohol
when dry, sand the excess 1/2" of cloth off hanging off the rear of the tube and sand the fin/tube area

Good luck,

Carl
 
Building it fast? I'd say. It appears Phil has the patience of a greyhound waiting for Rusty to come around the corner. :)

(For you non-greyhound racing types: Rusty is the fake rabbit the greyhounds chase during the race.)

Heeeeeerrree comes Rusty! :p
 
It's good to have friends... :)

Last night I glassed 4 fin joints. They came out pretty good. I did allow for more cloth this time. But I was doing this while staring down the motor mount. And thus the lure to put on the AeroPack was just too strong. So I stopped glassing.

Everyone may know this, but I'm in love with the AeroPack stuff. I think it is so cool and looks so good. And on the AMRAAM 4 it is no exception. JB Weld was used to cover the outside of the 54mm mother tube. Then the AeroPack was carefully slid over the tube. I used the rest of the JB Weld in a mixing cup. 10 seconds in the microwave and then the JB Weld was poured over the rear centering ring creating a strong barrier which connects the body tube to the centering ring to the AeroPack to the mother tube. BTW, this is my most favorite part of making a rocket. I don't know why it appeals to me, just does.

Here is a pic of the Mirage's AeroPack. I have a pic of the A4's but don't have it on the net yet.

https://www.cybergatetech.com/Projects/Rocketry/Pictures/Mirage/img_0755.jpg

Anyway, still having fun.
 
Well tonight I finished glassing the fins. 2 fillets were applied to the fins. I only had enough mixing cups to make two fillets. The rest will have to wait for me to buy more epoxy and more mixing cups. I also took time to apply hobby filler to all the bad spots in the epoxy fillets or anyother thing that needed covering.

The shock cords were sorted and quick links tied to the appropriate place according to the instructions. But I did come up with a question (Carl). With the CPR I now have 2 shock cords. One white tubular nylon and the second longer blue and white tubular nylon. I forget which shock cord goes where. Carl, did you have different types of shock cords? I'm assuming the white one goes with the drogue and the longer one goes with the main. Can you verify that?

Next question. I was test fitting the two fittings that connect to the altimeter. The one that slides down the CPR tube was very, very, very tight. In fact, I couldn't get it in more than an inch. Carl did you have that same problem? I sanded a little and it helped but I don't want to sand too much.

Still having fun... :)
 
Regarding shock cords, it sounds like you got it right. I have white tubular nylon cords for both sides, so yours is about the fourth color I have seen PML use so far. They have White, Black, Red and now Blue/White...sheesh. Using the longer one up top is what I would do; good call.

As far as the lower altimeter bay goes, yes, they are very tight! I did some light sanding to the inside of the tube and polished it with 600 grit to keep it smooth, but didn't want to over do it, which could wind up deforming the circular shape. I also sanded the outside of the lower plastic mount as it was binding a bit. Fit it this way first until the mount will fit in fairly easily. Did you insert it with the O-Ring in place? It will be very tight with the O-Ring, which is why I hit it with baby powder before inserting it. I lube the lower o-ring and mount area with baby powder and rub alot around the inside of the tube for lubrication, which helps with the insertion of the Altimeter.

Carl
 
Last night, the fin fillets were completed. Next on the plate is putting on the launch lugs. And don't worry Carl, I read your notes about this subject at least 3 times. :)

Since the upper body tube assembly is basically complete, I decided to start the finishing process. I sanded the fillets and all the extra epoxy with a 120 grit flap wheel on a dremel. It sanded OK but the fillets look a mess now. I decided to go ahead and put 3 coats of primer on it just to see if anything was really, messed up. Before I did, 220 grit sand paper was rubbed over the whole tube, canards, and fillets. The primer went on real well. I'm very impressed at how the Quantum tube accepted the primer. But the primer did reveal just how nasty my fillets are. I still have plenty of sanding to do. So, the upper body tube is now gong through its 24 hour dry time. It looks pretty good from a distance.. :)

I also used the flap wheel to try to sand out the lower CPR tube. It didn't work as planned. The lower insert is still way too tight... But I'm still working on it....

Still having fun... :)
 
The priming is finished on the upper body tube. It looks real good. The fillets are still a mess. I may have to spend some more time on them later.

I added the launch lugs. I'm pretty sure they are straight but I always worry about that. Tonight the fillets to the lugs will be added. The instructions called for 2" and 18" from the aft of the rocket. The 2" was fine but because of the CPR, 18" was not an option. So the 18" turned into about 24" since I couldn't find the correct distance in the CPR instructions.

Anyway, is there a special formula of where the launch lugs should be placed? Come on physics guys, tell me 24" was OK... :)
 
Nice to hear the primer is comming along; those Quantum tubes are a "dream" to paint!

Regarding your upper launch lug, since you said you read the review 3 times, here is an excerpt..."My upper lug was flush with the top of the lower CPR tube per PML's recommendation." I now find myself quoting Ken at his peak...

..."You buyem' books, you send em' to school..... all wasted!"

Your lug is TOO LOW!!! Mine is positioned per PML instructions AND via phone conversations and the BOTTOM of my lug is at 30"!!! What's worse is your rocket is a good six inches longer than mine, so the BOTTOM of the lug would be placed around 34" to 36" for good stability, nearly a FOOT higher than you glued it...you have some work to do.

The general rule of thumb is to place the upper launch lug at or near CG.

Carl

Famous Quote:
"...Somewhere out there is a village missing it's idiot...";)
 
Oooops, I guess I will buy a third launch lug and epoxy it higher... Or should I remove the upper lug and only have 2? I really did read the lug section 2 or 3 times. At some point, the upper part of the CPR translated to the lower part of the CPR... Oh, well.
 
Phil,

First off...I was just ribb'in ya; you have done very well so far and I am sure your efforts will make all of us proud and envious!

As far as the lug goes, if you did like I do, the lug and tube surface were sanded with 80 grit paper and will not budge. It's probably easier to just add another one. Also, check your paperwork...the lug positions for CPR were a separate single paper and not in the manual.
 
I don't think I got that extra sheet. Anyway, I think I will add a 3rd one... :)
 
Lots of little things done today. I spent more time with the primer. I sanded and primed the upper body tube. I also sanded and primed again the Mirage. :) Tomorrow night the upper body tube will be ready for 400 grit sanding and a color coat. Speaking of color coat, the nose cone got 2 coats of color. A nice white. There is just something strange about taking a white nose cone, painting it grey with primer and then painting it white again with a color coat.

I also took time to make the fillets for the launch lugs. I have decided to add a third launch lug. Home Depot had a 4' 1/2" dowel rod that I bought to make sure the lugs were aligned. The two that are down are in good shape. Now I need to buy another lug and I'm good to go.

Getting down to the small nit picky stuff now. Almost time for finishing. I'm still having fun...
 
Well the upper body tube now has one coat of white paint. It looks pretty good. I also found out (thanks Mark) that I may have been doing the fillets wrong. (Don't ask) So I tried the new method and it worked a ton better. However, it now means each fillet has about 1.5 oz of goo. :) Anyway, still having fun...

I painted the Mirage tail green and am in the process of making pics.
 
 
By looking at the pictures you can see that the upper portion of the rocket is complete except the decals and a final coat of clear. 6 monster fillets are now poured. I haven't done the last two on the fins cause I screwed up one of the adjacent areas and need to wait until it cures before so I can fix it. Other than that, sanding on the lower fin area begins tomorrow... :)
 
Holly cow... now them there aint fillets.... there steels angle iron supports... and just as heavy... I guess I don't have to tell you that it's about 6x too much fillet, unless this was the look you were after.. Let me know the next time you start a HPR, I'll up my stocks in epoxy.
 
Well Phil,

It looks great, although I will have to say your fillets on the lower fins are even bigger than mine! I doubt they will ever give...The fin should collapse first!


The upper section and nose cone are really nice. You are at the point now where you can probably finish the lower CPR tube if you put on the upper lug. That means 3/4 of your rocket will be painted so you're comming down the home stretch...Now comes the fun stuff...finishing :)
 
Woo-Hoo... All the fillets are poured and look fantastically immense. :) Now for shaping and priming the lower section. The lower CPR section will have to wait for the launch lug stuff I ordered.

Still having fun...
 
The monster fillets were shaped and primed. I primed them in grey so I could see the flaws better and found that I have a little more work to do. One fillet (the one side of the launch lug) will have to be replaced as it did not harden. Oh well. Everything else looked pretty good in the grey.

Tonight I will replace the fillet and finish priming/sanding/filling the lower part of the rocket.

Still having fun...
 
Tonight I primed the lower part of the rocket. it exposed alot of areas that need work... Parts need to be filled, and I need to do 2 more fillets (2 of them didn't harden.) Now comes the tedeous (is that how you spell it?) part, the shaping and filling.

Still having fun.
 
Well folks, the third launch lug came today. Everything was lined up with loving care. Fillets were added to the lug and they came out great. I shaped them and then primed the lower CPR section.

2 of the fin fillets didn't cure so I had to pull them off. That was a chore. Anyway, they were removed and new ones poured. The new ones turned out great.

Tomorrow night I will shape the remaining 2 fillets, then fill in all the oooopses. The rocket will be primed and sanded. Waiting for the final lower color to materialize.

Starting to do research on custom decals. My findings so far: Decals and Laser Jet does not work...

Still having fun...
 
Whatcha mean "Decals and Laser Jet does not work" ???

Of course they do...let me guess...they smeared. Bet you forgot to select paper type as card stock; with that setting, toner is applied lighter so it doesn't smear going through the fuser.

Good report! Let me know more about your decals. BTW, how's the epoxy doing??? ;)
 

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