LOC Magnum 3E Build Thread

Got started on glassing the tube ends. Using "peel ply" for the first time, I like it so far. I'll
know for sure when it's dry and I "peel" it off.
Placed an empty 10 gauge shot shell on the top centering ring and epoxied it in place. This
will be my charge well. I plan to use a charge wrapped inside a smaller plastic tube with hot
glue sealing the ends of said tube.


JP

https://www.missileworks.com/store/#!/~/product/category=5760485&id=25239688
Been sanding on the tubes, the epoxy came out thicker than expected. Next time I'll know
better than to lay up as much.
Got the Missile Works RRC3 Altimeter mounted to the Sled. One set of screws goes into the
cross brace. I used "Servo Grommets" as the spacers, sort of gives it a semi-soft mount.

I'm thinking there's enough room to mount 2 batteries/trays on the opposite side and still have room
for one more "back up" Altimeter. Probably get the RRC2 for that.

JP

Got the tubes sanded where I want them, just need to use some finer grit and slick them out.
Pictured is the tubes put together with Av Bay and Switch Band, in order to level the epoxy on
the Switch Band...


JP

I added another slab to the Sled for the batteries. I epoxied the 9 volt trays in place and drilled
a few slots for Zip Ties to secure the batteries...


The battery trays and Screw Switches are from Missile Works.
https://www.missileworks.com/store/#!/~/category/id=5704273&offset=0&sort=normal

JP

Last night I placed an order with Dog House Rocketry. Ordered the Dual Altimeter Wiring Kit.
Although I just spent $9.00 at Radio Shack for 3 rolls of 22 gauge wire, I remembered some
of you guys mentioned using these kits.

https://doghouse.blastzone.org/altimeter-kits.html

JP

Just about got everything sanded smooth and ready for a primer coat. Dry fit the rocket again with pics.
With the Tail Cone added to the Magnum is now an inch from the ceiling.


Inside shot of a tube shows a thin layer of epoxy. Shouldn't get any pyro burns on the inside!

JP

I fear that that boat tail is going to be sacrificial in one or two ways:

1. The motor is so recessed that any 54mm motor is going to cook it and cause bubbling/burning of the epoxy.

2. It's unsupported and anything except for a really soft landing under and oversized main parachute on soft sod or grass is going to crunch it.

Have you thought about these things and how to mitigate them? I love the look, but feel it will cause you anguish without reinforcing it or moving the motor nozzle aft.

patelldp said:

I fear that that boat tail is going to be sacrificial in one or two ways:

1. The motor is so recessed that any 54mm motor is going to cook it and cause bubbling/burning of the epoxy.

2. It's unsupported and anything except for a really soft landing under and oversized main parachute on soft sod or grass is going to crunch it.

Have you thought about these things and how to mitigate them? I love the look, but feel it will cause you anguish without reinforcing it or moving the motor nozzle aft.

Click to expand...

I've added one more layer to the tail cone, total 5 layers of glass. I stood on top of it at 4 layers. I weigh 200 lbs.
There's a paper ring I glassed that will fasten to the top of the tail cone that will help support it's shape and strengthen
the whole tail section as well. The Epoxy I use is G-Flex. The best epoxy I've ever used to date. It's Super strong, puts
Bob Smith in the dust.
I hope to use the Aero Pak 54mm adapter, that shouldn't come up short plus the nozzle length.
The 75mm retainer is flush with the end of the tube.
Thank you for posting on the thread. I was wondering if anybody was watching the build.
Maybe you won't be able to say I told you so! :wink:

Now I'm considering using screws to fasten the tail cone, that way "if" it gets burned I can remove it, make another out of Kevlar...

JP

I'm still watching! Looking good!:clap:

Subscribed.

JP Morgan said:

Now I'm considering using screws to fasten the tail cone, that way "if" it gets burned I can remove it, make another out of Kevlar...

Click to expand...

You won't burn fiberglass, which is made of silica. You might boil away all the epoxy though as happened with my Nike-Asp due to base drag and a long-burn motor. (The epoxy burned away and the cloth was flexible again!)

I've got everything sanded and primed. Did that for 4 days and filled in seams and pin holes.

Currently working on testing of blast caps I've made from aluminum containers. Best price I
found was at Optics Planet. https://www.opticsplanet.com/ust-base-case-aluminum-1-0-capsule.html
The Lime color is not a true Lime, as shown it's dull green which is fine with me. I've only tested one
charge at 1/2 grain of BP and that was the bottom piece that I cut off. Real test to come using the top
half mounted to 3/4" plywood. Using the bottom half should be the better piece to use as it's got a thicker
wall. I'm thinking I should notify my neighbors before I set off the larger load. We live in the County so it's
no big deal but there are houses on 3 side of us. I'm also thinking about taking the tests out to my Moms
house in the Country to our Firearms Range. Anyone near by know there are always explosions and bangs
that come from there!



JP

I also ordered some of these to test out.
https://www.ebay.com/itm/310673723439?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
I got the silver and the red, main, back up.
UPDATE: these are too heavy and the cavity is too small.

JP

I like the way you think when it comes to Re-purposing things!

TopRamen said:

I like the way you think when it comes to Re-purposing things!

Click to expand...

Pretty Slick hu! Thanks TR.
Tested the cap up to 2 grains. Amazing at the pressure you'll get from one more layer of tape to the top
of the cap tube, I'm using electrician tape...
Clean up of caps...

Frog tape has patterns pre cut.
I'm thinking diamond patterns for the Magnum.

Nose cone ready for paint.

Fin Can primed.
First I used sanding sealer then primer.

JP

Started painting today. Going with Burnt Copper, Gloss Black and Metallic Silver on the
Switch Band and Tail Cone.

Tinned all the wires to the Altimeter and dug up some tiny bolts and nuts for the "screw switch".
Tinned wires will hold up so much better than a bare wire, it's crazy Not to tin them...
https://www.missileworks.com/store/#!/~/product/category=5760490&id=38076724
https://www.missileworks.com/store/#!/~/category/id=5704273&offset=0&sort=normal


JP

First coat of paint on the Magnum 3.
These are the same colors on Neond7' Big Nuke 3, although I'll
add another color maybe two to change it up a little.
The Burnt Copper is tricky to lay down. It's thin and requires several thin coats within
the first hour. 7 day wait to recoat.
The nose cone is finished with it's paint. Got one more coat to put on the upper tube.
This changes up the graphics Mark drew up for me but I'll think of something.

The black is Ace brand and is Thick! I don't like that but I've got to go with it now.


JP

Got the finish coats on the upper tube and nose cone. I like the Burnt Copper VHT paint from Auto Zone!
The can has the good nozzle tip that's adjustable 2 ways.

I took back the other cans of ACE paint. I do not like the stuff! It's thick and takes forever to dry. It doesn't
stick very well either.
So I went back to Auto Zone and picked up 2 cans of Metallic/Pearl Black. Still I need to wait on the already applied
ACE black to fully cure and sand it down smooth then I can shoot it with the good VHT paint.

I epoxied the fin can in and used 2" strips of glass cloth to secure the fins to the tube. See photo...


JP

JohnCoker said:

You won't burn fiberglass, which is made of silica. You might boil away all the epoxy though as happened with my Nike-Asp due to base drag and a long-burn motor. (The epoxy burned away and the cloth was flexible again!)

Click to expand...

I had a look at that John. That was nasty indeed.
I'll stay clear of using long burn motors. The Club field is big but I'm not comfortable with sending them over 3,000' just yet.

Thank you for posting!

JP

I couldn't stand that Crummy ACE brand black paint. So I painstakingly wet sanded it off.
Using Krylon semi-flat black this time as a primer undercoat. Says it can be recoated after 24
hours. I see a few places that need filler so I'll get that tomorrow, prime those and maybe shoot
a finish of the Metallic Black by VHT.


JP

JP Morgan said:

I'll stay clear of using long burn motors.

Click to expand...

I don't mean to scare you off long-burn motors; they're key for sustainers. This motor was a 22s burn N and recessed into the aft end of the rocket (due to the staging arrangement).

JohnCoker said:

I don't mean to scare you off long-burn motors; they're key for sustainers. This motor was a 22s burn N and recessed into the aft end of the rocket (due to the staging arrangement).

Click to expand...

Dang! 22 seconds!!! I'll probably never burn anything like that. How much did you pay for that N motor?

First motor for the Magnum 3 will be a 54mm K. I'll have to SIM the motor, when I get it, to see how high and of course
burn duration. I still haven't drawn up the Magnum in Open Rocket, being lazy on these cool days we've had lately.

* I don't care anything about high altitudes, all I like for now is the slowest possible flight while keeping things stable.

JP

JP Morgan said:

Dang! 22 seconds!!! I'll probably never burn anything like that. How much did you pay for that N motor?

First motor for the Magnum 3 will be a 54mm K. I'll have to SIM the motor, when I get it, to see how high and of course
burn duration. I still haven't drawn up the Magnum in Open Rocket, being lazy on these cool days we've had lately.

* I don't care anything about high altitudes, all I like for now is the slowest possible flight while keeping things stable.

JP

Click to expand...

Simming can be a real Drag.
I'm with you on the Altitude thing. Once it goes out of sight what is the Point?

Bummer about the Paint, but thanks for sharing your Experience so that others can learn from it.

TopRamen said:

Simming can be a real Drag.
I'm with you on the Altitude thing. Once it goes out of sight what is the Point?

Bummer about the Paint, but thanks for sharing your Experience so that others can learn from it.

Click to expand...

Re: altitude, you out West you can see rockets really high in the air. I have tracked a rocket to 30k with the naked eye.

Made Fillets with LV Epoxy, then the fun begins making them even.
Placed 3 separate strips of Glass Cloth on the inside of the tail section to give it strength
and I may screw the Tail Cone instead of gluing it in place.
The Red Aluminum piece previously shown is not going to work out at all. They are too heavy
and too shallow for my liking. So I'll use the original tubes I cut down.
I've tested these containers up to 2.6 grains of FFFF Goex BP. No stress showing, just a slight color loss
on one side.


For the finish colors and scheme I'm thinking about adding the light blue as in the G-Force rocket to the upper section
swapping the colors around where their silver is make that my light blue and using the yellow squares too. I like that scheme!

https://www.redarrowhobbies.com/kits/aerotech_model_rockets/g_force.htm

JP

FWIW, I used the same kit for my L3 on an M1297 and got about 7500' Nice day and I saw the whole flight.

On a side note, have you looked at Gary T's Blastcaps for the charge canisters?

H_Rocket said:

FWIW, I used the same kit for my L3 on an M1297 and got about 7500' Nice day and I saw the whole flight.

Click to expand...

That's nice to hear.
I would love to do the same but the "rules" won't work for me on this one. I like the NAR but strongly disagree
with some of their rules we need to follow.
I plan to burn a K motor in a 54mm case, reduced of course from the 75mm.

Thanks for posting!

JP

H_Rocket said:

On a side note, have you looked at Gary T's Blastcaps for the charge canisters?

Click to expand...

Yep, I saw those. They look to be well made. I like to repurpose things like TR says and I saved some money too.
If these play out or burst I may use those second time around.

JP

I need to locate a retention device for the wires coming out of the Altimeter so they don't get
pulled on, the Blue and Orange wires... Any ideas?

I've got RC56 in and around the holes for the wires going to the charge canisters. If you've
never used RC56 it dries clear and is flexible too, very tough on holding and chemical resistant
to allot of stuff. It should do nicely here.


JP