PML MR-1

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I finally got around to the hardware store an picked up some #4x3/4" screws. I drilled the lug standoff after maring the holes through a linear lug and then screwed each of the 2 screws in. The screws were then backed out and a batch of 5 minute epoxy was prepared. Epoxy was spread on the standoff, the lug was put in place and the screws were tightened. A fillted of epoxy was then run along the joint between the base of the lug and the standoff.

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I still have not had a chance to fly this one but I have done some more work.

I really liked the photo of n3tjm's and decided to do something similar. I taped off the end of the NC and spread some foil to keep the paint from affecting anything else.

MR1-masked-for-red-1.jpg
 
The MR-1 then made a quick trip to the booth where I shot it with some glossy red.

MR1-red-1.jpg
 
The first flight of the MR-1 was a comic tradgedy of errors. I checked and saw that I had put the chute in place and loaded an Econojet F20-4. It came with a Copperhead igniter, of course, but I had never had too much trouble with those...until today. It didn't even tickle the motor.

MR1-f1a.jpg

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I replaced the igniter with a First Fire and got ignition, after a fashion. the motor chuffed for a while but then decided to go with the flow and the rocket took off describing a parabola. At this point, we all knew that trouble was brewing but I kept hoping that, somehow, the chute would eject. I ran around a truck that was ubstructing my view and had just enough time to see the following:

1. The ejection charge fired about 10 feet off the ground.
2. The chute was in the tube but had not been tied into the harness (It flutters nicely, by the way)
3. The rocket takes a core sample.

Some of the excitment can be seen here: https://www.flickr.com/photos/23694991@N03/3625553191/

MR1-f1f.jpg
 
Things got stranger after that. The first really strange thing is that the rocket had NO Damage. That made me think it was indestructible and ready it for another flight.
 
This time I loaded a G38-4J. I tried another copperhead with the same result as before and replaced it with a Quick Fire which did indeed fire quickly. The rocket flew well, went up, sounded good, the piston deployed the chute just the way it was supposed to and the rocket came drifting down. That's when the winds decided to act up and take it towards the Alamo Fireworks warehouse. Ignoring my pleas, it landed on the wrong side of the fence.

Several of us saw it land gently. I decided to go on Monday to reclaim the rocket. Alamo has always been very good about that. At the end of the day, though, another club member was driving off and noticed their gate was open. He retrieved his own and my MR-1.

To summarize thus far: the rocket augered in on its first flight and sustained no damage. Now it had landed gently the way it is supposed to and it popped a fin.

A video of the second flight can be seen here: https://www.flickr.com/photos/23694991@N03/3625645031/

MR1-f2a.jpg

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Shame about the fin.

Here's a pic of my MR-1 on a H128 yesterday. This was its first flight since I installed rail buttons, and funnily enough, the first flight it flew straight :) This is the first time a rocket of mine has been photographed with mach diamonds too :marshmallow:

I had a long walk to recover it, and found the nosecone, chute and piston had landed in a dam. I wonder how it'll go on a bigger motor.

test004.jpg
 
Shame about the fin.

Here's a pic of my MR-1 on a H128 yesterday. This was its first flight since I installed rail buttons, and funnily enough, the first flight it flew straight :) This is the first time a rocket of mine has been photographed with mach diamonds too :marshmallow:

I had a long walk to recover it, and found the nosecone, chute and piston had landed in a dam. I wonder how it'll go on a bigger motor.

test004.jpg

That looks good.

I want to try an H but need a bigger field than I have right now.
 
The main damage after my MR-1's initial outing was a popped fin. The bond on the motor mount and on the airframes seems to have failed and the fin pulled out just a bit.

Besides that, the problems were purely cosmetic. THe silver paint I had used didn't like its rough treatment.

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The fin took some effort to remove. It was loos but really didn't want to come out and it had to be persuaded with a pair of pliers. Once out, the reason for its recalcitrance was obvious. Some globs of epoxy were hanging on and didn't want to come off.

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A little bit of time with a file and some sandpaper convinced me that getting off my lazy backside and walking over to the belt sander would be a good idea. Once there, the root was smoothed down quickly and I was glad to learn just how durable the fiberglass fins are.

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Next up, I wanted to clean off the paint and the fillets from the airframe. Most of the material was removed with an X-acto and a little filing finished the job.

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Some 5 minute epoxy was then applied to the root and along the slot and the fin pushed into place. Fillets were formed with more epoxy, albeit they were not very pretty ones.

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I built my MR-1 stock. It pops a fin pretty much every time it flies. actually I think it's flown 2 or 3 times without popping a fin. It's heavy so an F40 is weak for it, but F52s are good and G104s rock - all the way to like 700'.

after 3 years I finally painted it, camouflage green/brown/black. on the first flight, the nose paint cracked, I think it must have hit a fin.

what the heck. it's cool it looks great and I think would work well as like a BT60/BT50 downscale.
 
Shame about the fin.

Here's a pic of my MR-1 on a H128 yesterday. This was its first flight since I installed rail buttons, and funnily enough, the first flight it flew straight :) This is the first time a rocket of mine has been photographed with mach diamonds too :marshmallow:

I had a long walk to recover it, and found the nosecone, chute and piston had landed in a dam. I wonder how it'll go on a bigger motor.

test004.jpg

Wow! That's a really nice launch picture. Nice diamonds too.:eyepop:

I just saw this; what is that little thing jutting out to the left of the nose cone transition? It looks like a lug on a standoff...
 
Wow! That's a really nice launch picture. Nice diamonds too.:eyepop:

I just saw this; what is that little thing jutting out to the left of the nose cone transition? It looks like a lug on a standoff...

Yep, its the standard lug installed as per PMLs design. I originally installed the lug and glassed it in place, but found I'd get too much rod whip so moved to rail buttons.
 
I let the epoxy fillets set up for 2 days and then masked off the upper regions of the rocket. After some dilligent searching, I managed to find the same green I had originally used and began to paint it. This not only covered the repair, it also fixed up a few of the dings in other places.

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I took the masking off that had protected the silver from the green and it looked OK but I still needed to tackle the silver. It seemed to have been exceptionally weak in bonding to the plastic.

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Some sandpaper was then used to scuff up the nose cone a bit and the body and tip of the NC were protected with tape and foil. The rocket was then set up in the booth and shot with silver.

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The masking came off and the MR-1 is ready to fly again.

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My MR-1 has sat for a long time since its repair job. I meant to give it an outing last Saturday but ran out of time. Instead, I launched it yesterday after a Cub Scout launch. The piston was sanded down a bit to make is slide better and then it was fitted with a Roadrunner G80-7 and taken to the rail.

MR1-f1a.jpg

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When the button was pushed there was the briefest hint of smoke and then the motor roared to life.

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The ejection was good and it drifted down with the emphasis on "drift." It landed on the shoulder on the other side of US 87 with no damaged.

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A while back, my MR-1 was going to fly at a club launch but I never got around to it. It then bounced around in the back seat, fighting with the other junk I had tossed back there, and wound up with another popped fin. This was the only fin that had not been worked on before so I guess it was time.

popped-fin-1.jpg

popped-fin-2.jpg
 
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