The Re-construction of the Manta Bomber

[kelltym88]

On it's one and only flight, the Bomber suffered some pretty significant damage. While the flight itself was just picture perfect, the landing, ehh, not so much. Of course it landed on the weakest part of the whole thing, and that is where the damage occurred. These picture show the damaged areas.

 

[kelltym88]

So after racking my brain, I finally figured out how to fix it. At first I thought I could just wrap the damaged areas with another tube, like this:

 

[kelltym88]

But further examination revealed that the motor tube was too badly damaged. I knew that the whole thing would have to come off. But I did not want to remake those sections, so, to my surprise both of those sections actually came out rather easily...

 

[kelltym88]

You can how bad those motor tubes are. The next step was to grab my Dremmel and start cutting. I cut along the fin on both sides, and then removed what I could of the body tube. I did that on all 4 sides. Then I took a heat gun,(it is actually a propane torch), and heated up the area around the CR and the lower section. I got the CR off ok, but the rest of the motor tube required some more elbow grease. After torching the lower section, I was basically left the motor tube remains. So I grabbed a drill, and a 1 1/8" butterfly bit and bored out the whole until I could get the new motor tubes to fit. Here are some pics in progression.

 

[kelltym88]

It actually wasn't as difficult as I thought it would be. Both are ready for the next step. Yes , the motor tubes are a little shorter, but as I put it back together, you'll see why. Right now I'm just waiting to pick up some body tubes so I can continue.

 

[stickershock23]

Tim,

You ought to make it so it lands flat somehow, I bet that would help out on that landing a bunch.

Maybe run a piece of kevlar thread on the outside of the rocket to tie to the back of the center tube. so the rocket is slung in two places like the old estes mercury redstone kit did.
looking great so far.

 

[Pem Tech]

I agree with stickershock23, a Kevlar harness would elevate some of your problem, our Bucky Jones uses 300 lb KEVLAR twine to come down horizontally so those cool pointed fins don't break off.

Is there a manufacturer for the Manta Nosecone?
That would make a cool clone.

 

[troj]

I remember that rocket!

https://www.rocketryonline.com/rolpresents/LDRSDay3a/pages/IMG_9035.htm
https://www.rocketryonline.com/rolpresents/LDRSDay3a/pages/IMG_9036.htm
https://www.rocketryonline.com/rolpresents/LDRSDay3a/pages/IMG_9037.htm

-Kevin

 

[kelltym88]

Mark, I will toy with that idea once it's finished.


Layne, I made that nose cone all from scratch, using 3/8" ply and foam.


Kevin, yep, that's the one. Those are some great pics.

 

[kelltym88]

OK More progress. I had one tube left over from the original build, so I used that to get one side prepped. Basically what I did was slip the tube over the existing CRs until they stopped at the fins. Marked the at each location, measured up 4", drew lines connecting them together and cut 4 slots out so they could slip around the fins and down to the lower CR.

I had made some bulkheads previous, so I took 2 of them and disc sanded them to fit inside the coupler tubes. Once they fit, I drilled 4 holes. I inverted each section and used the bulkhead as a guide and drilled for starter holes around the bottom of the lower CR. Then proceeded to drill the hole thru the entire set up all the way thru the top CR.

I had pre-cut 8 pcs. of All-Thread which I proceeded to insert thru each hole. These will run thru the entire lengh up thru the bulkhead in the coupler. My thinking on this was so that it would beef up that lower section.

Here are the pics of the whole process:

 

[kelltym88]

More pics:




Just need to get one more tube and a coupler and I can get the other side ready.

 

[kelltym88]

OK, more work has been done. I got both tubes cut and ready to slip down over the existing cr's and lower section. Here is a picture of how I clamped it together.

 

[kelltym88]

One of the sections had voids from the original foaming session. I drilled a couple holes big enough for the foam tube to fit and foamed it. After it dried, I removed the excess and proceeded. I epoxied the bulkheads to the couplers, then the couplers to the tubes, then ran the all thread thru and secured the nuts. Put a dab of epoxy on the nuts. After everything dried, I grinded down any excess. Then I epoxied the finished sections to the exisiting. Then I wrapped 5 oz. glass around both joints. I cut 8 individual pieces to in between all the lower fin sections and glassed those on. Here are some pics:

 

[kelltym88]

Then it's sand, sand, sand. I am not very good at making clean cuts, so when I glass I get alot of strings and glops and uneven areas, which makes for alot of sanding. Ugh! That is definately an area I need to improve in.


Anyway, time for fillets. And a small repair on the wing, and, you guessed it more sanding...

 

[kelltym88]

A couple coats of primer, some wet sanding, and a couple coats of white and viola! Ready for decals.

 

[kelltym88]

I have applied the decals. I got them from Stickershock. I must say, they are friggin AWESOME!! They make this rocket just POP! I changed from my design to the original paint scheme, and man it looks so much better. I haven't taken pics of the finished product yet, but don't worry they're coming.

 

[MarkM]

Is there a manufacturer for the Manta Nosecone?
That would make a cool clone.

Yup. Sirius Rocketry sells a poilyurethane version of the original Manta Bombr NC (BT-50 size). These were once Moldin Oldies, but he sold off the business to Sirius. I ordered a few clone NC from M.O. before he sold to Sirius...nice reproductions of impossible to find NC.

Here's the link

 

[kelltym88]

" And now, here's.... Merv....."

 

[kelltym88]

Going to Rocstock, in fact I'm leaving right now. I doubt it's gonna fly 'cause I don't have the caish, but it sure looks pretty.

 

[MarkM]

Going to Rocstock, in fact I'm leaving right now. I doubt it's gonna fly 'cause I don't have the caish, but it sure looks pretty.

Sure does. Looks better the second time around! Impressive reconstruction...hope this one holds up.

 

[BB-ROCK]

Manta looks good second time around...:cyclops: