santa brought a magnum

I chose the Loc Magnum because I think i t will be a good rocket to learn on down the road. I will add an additional centering ring, two more 29mm and some conduit for air starts. As of now I think the rest will be stock. As time, money and experience allow, I would like to play with dual deployment, air starts and posssibly hybrid power. With those objectives in mind, is there anything I should (or should not) do now to plan for the future? This is a great kit with the usual Loc craftsmanship.

I just recently found your site. You guys do a great job.

Dude, I am sooooo jealous... I wanna magnum.... Make sure you take plenty of pictures during your build and post them here.

Well, I would recommend at least glassing on the fins. With your plans for the future it sounds like this bird might take some serious kicks. If you have the time and money, two layers of 6oz. 'glass on the airframe would be good.

Also, make sure you leave room for a timer bay in the lower section for those future airstarts. Finally, make sure that your shockcord can be replaced in the future. Use a u-bolt and quick link as long as there is room to do this.

I'm sure the other guys have some more suggestions though...right?

David

Thanks david. How low in the air frame will the airstart timer have to be and if I leave this thing stock will I be able to install it after construction? The main motor tube is 27 inches long and the 29s will be around 11 inches.

Thanks for your input.

If you really want to be able to use the Magnum for hybrid power, you are going to have to make the booster section longer than 27 inches. I think the minimum for hybrid would be 36", and I think that will only get you J's with the HyperTeks. I'm still learning about hybrids, but you had better go look up some specs on the various types. The main disadvantage to hybrids is that they are a lot longer than equivalent solid fuel motors. I might be mistaken, but I believe some of the hybrids could be as long as 48" - maybe even longer.

Check your specs and plan carefully before you build if you intend to use hybrids.

Okay, this is how I would install the timer bays.

First, you don't need to cut the 29mm or 54mm tubes any shorter than they are. Secondly, I would recommend getting two more CR's. They should have holes for a central 54mm and two 38mm tubes on opposite sides. Then install the one CR just forward of where the 29mm motor mount tubes stop. Install the other at the very forward end of the 54mm tube. You should have 2 38mm tubes installed that are almost flush with the forwardmost CR but extend aftly through the other CR with the 2 38mm holes in it a couple inches. Bulkheads (with small holes for 1/4" copper piping) should be epoxied into the aft ends of the 38mm tubes. Then, run copper piping (two pieces) from the aft most centering up through the bulkheads in the 38mm tubes. These are the conduits. Then, you can install two ST-1 or Accufire timers into the 38mm tubes using PML's urethane holders. Secure the timers with a few bolts with mirror clips like you do for motor retention. Then, when you want to fly, just run the e-matches down the conduit, out the aft end, plug them into the motors and attach the other ends to the timers and screw down the timers.

Most of this needs to be done during construction, not afterward, but it is rather inexpensive except for the timers and urethane holders which can be purchased later. I'd say except for those things, it would cost about $35.

The good thing about this setup is that it is lightweight, it can airstart the motors in pairs or all 4 together and it means that there are no hatches on the side of the rocket so it doesn't distract from the finish.

Well, that was a mouthful. If you need a better description let me know, I can draw a quick little pic for ya.

David

PS- I don't do hybrid so I don't know.

Thanks Ken. I'm glad I asked before I built. Usually I build and then ask. I will check the specs with hypertek.

This forum gizmo is pretty slick.

Maverick: Very neat idea. I think I will need to read this a few more times but I get the general drift. A drawing would be very helpful if you have the time and inclination.

Having friends over for the Fiesta bowl. Gotta go get Tostitos and beer. Buckeyes are going to have their hands full tonight.
Hope it's not another blow out like last nights shelling.

Thanks to all.

Yeehaa...another new kit!!! Good for you man, I want to see pics!!!

Carl

No problem, I'll get a pic for ya in a day or two.

BTW- I got so carried away I forgot to say welcome to the forum dude.

David

Originally posted by KenParker
If you really want to be able to use the Magnum for hybrid power, you are going to have to make the booster section longer than 27 inches. I think the minimum for hybrid would be 36", and I think that will only get you J's with the HyperTeks.

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For 54mm HyperTek motors, the longest is 30". You don't have to support 100% of the tank length. If your MMT is 27" long, you'd be OK even with the longer 835cc tank if you've got the room above the MMT to allow the 3 extra inches of tank to stick out. The 440cc motor is 24.3" long and the 300cc motor is 20.5" long. The bigger issue is providing a way to vent the N₂O to the outside. This is something that you'll have to consider before you build.

Buckeys rule. Sorry Jim Rome. Sorry Brent Mushburger,
Sorry Miami, Sorry Nationaly Famous Pundits, Sorry U.S.C.

What excuse will you come up with on monday to cover your ..............

I can't wait to hear your back pedaling.

Mediator: I know that this is a rocket forum, please forgive me but THE BUCKEYES JUST WON THE NATIONAL CHAMPIONSHIP!

Originally posted by kersplat
Mediator: I know that this is a rocket forum, please forgive me but THE BUCKEYES JUST WON THE NATIONAL CHAMPIONSHIP!

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Ok, you are forgiven... Back to rocketry.
Have you finished building your Magnum yet? Dude, I would have been up all night with it...

Baby steps my friend. If I built this rascal stock I probably would be up all night. Adding motors, electronics, dual deployment has me thinking a lot more than building. I am delving into areas of the unknown (to me). makes me shudder and quake sometimes but don't tell anyone. This project is going to require the technical
expertise of you, Maverick and any one else who wants to chime in.

If you built a rocket by committee, I wonder what it would look like?

:blushing: You have my expertise bud...

Hey kersplat,
I have a pic of a drawing for you and a rocksim file. They are too big to post on the site, so, what's your e-mail and I'll send it to you?

David

PS- If you don't have rocksim, I highly suggest you get it because you will need it to find the best airstart times on those 29mm motors.

Originally posted by MaverickLV
so, what's your e-mail and I'll send it to you?

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You ought to be able to send him a private message thru the forum.

OK men, here it is.
Objective: design, build, fly and recover in one piece.
What: Loc Magnum
Why: Giggles
Is that the only reason? Yes
Is that really the only other reason? no This will be a L2 shot.
Completion date: Feb. 7 2003.
Rules: none
Veto Power: Maverick and me but mostly me.
Rocket name: Pgerringer: nice ring to that and he wants a Mag.

Since I have the Kit it will be set up like this.

Add 2 more 29mm outboards for a total of four 29mm and one 54mm main. That configuration would not allow for 3 fins to be mounted to the motormount so I decided to go with four fins. Barry is sending another fin and that should arrive tuesday. The air frame has been stripped of glassine in preperation for glassing.

This bird will be configured for: Air starts, dual deployment and possibly hybrid. Barry Lynch told me that venting for hybrid could be done post construction. He also said that support equipment could be rented rather then bought.

Yikes I'm out of room. talk too much I guess.

Originally posted by kersplat Rocket name: Pgerringer: nice ring to that and he wants a Mag.

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That's just plain sick!

Originally posted by kersplat Barry Lynch told me that venting for hybrid could be done post construction.

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That's true but, it usually involves drilling a hole through the airframe to allow the N₂O to vent out the side.

Originally posted by kersplat He also said that support equipment could be rented rather then bought.

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That's good to know. Most larger clubs have HyperTek GSE available.

Originally posted by kersplat
Rocket name: Pgerringer: nice ring to that and he wants a Mag.

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OMG!!! ROTFLOL!!!! I think I hurt myself... I just hope your rocket doesn't crash and burn. That would be such a blow to my ego...

Originally posted by MaverickLV
Hey kersplat,
I have a pic of a drawing for you and a rocksim file. They are too big to post on the site, so, what's your e-mail and I'll send it to you?

David

PS- If you don't have rocksim, I highly suggest you get it because you will need it to find the best airstart times on those 29mm motors.

Click to expand...

David,
I sent you a P/M and an e mail. Did you receive them?

A rocket named Pgerringer.... OMG. That's disgusting.

I'll have to go let some air out of Phil's head after that.

Yeah, I got the message. My e-mail response is on the way.
Talk to you soon.

David

In response to what Maverick was saying about extra centering rings, I need a picture!
I have a pic of the main motor mount for the magnum on the server at "Dr Don's magnum" if the link works.
Where exactly do the additional rings go.What is the purpose of the 38mm tubes, And do I have the original 3 CRs in the right places. I have a 29/360 motor in the 1 outboard tube for scale. Thanks!
Dr Don

I don't see the link. Try to repost it so we can see what exactly it looks like.

TTYL

David

Ok! Lets give this a try:
https://www.cybergatetech.com/phpgraphy/?dir=rocketry/misc/dr Don
This should work if I copied it correctly. Don

Ok! Lets give this a try:
https://www.cybergatetech.com/phpgr...copied it correctly. Don

Is this what you are trying to do?

https://www.cybergatetech.com/phpgraphy/?display=Rocketry/misc/Dr Don/magnum/dcp_0069.jpg

I find it easier just to copy the Address bar of the browser and paste it here. Or, you could click on the https:// button when you are posting the reply and get something like this: Dr Don's Magnum

Hmmmm, that's not working...

https://www.cybergatetech.com/phpgraphy/?dir=Rocketry/misc/Dr Don/magnum

OK, that time it worked. I'm not sure why the previous link didn't.

Dr. Don,
The lower CR is in the correct position. Then, I would place the next CR (with holes for the 29mm MMT's) above it so that it touches the forward edge of the fin tangs when installed. This way the CR's effectively "pinch" the fins in place. Then place a CR at almost the very end of the tube. Maybe have just .25" of tube exposed forward of the CR. This would have two 38mm holes in it opposite each other as well as the main 54mm in the center. Place the 38mm tubes (about 8-10" long) down these holes in the CR's until only .25" of tubing is visible. Place the last CR (with both 38mm holes and the 54mm hole) down about 7" from the forward end. The 38mm tubes hold the timers. This elminates the side hatches in the body.

Do you have rsim? I can send you a file if you do?

David