Big Daddy Recovery/Ejection Modification?

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OKTurbo

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I've started working on the Big Daddy I rec'd as a gift for Father's Day (how appropriate). The thing is practically all nose cone....
I'm building this one up to be a workhorse for my RMS 24/40.

The modification I'm thinking of doing is to replace the BT50 engine tube with a longer one that will go up into the plastic nose cone like a long stuffer tube. I'll enlarge the existing hole in the bottom of the nose cone so the BT50 tube will fit into it. The idea being that the ejection gases and particles will go into the nose cone and protect the chute/shock cord like a baffle.

My concern is whether the plastic nose cone will be OK. Are little burning chuncks going to melt a hole in it? The plastic is fairly thick. Or would it be prudent to try and coat the inside of the nose cone with epoxy....or a layer of foil...or even stuff a "Chore Boy" up in there.

Has anybody done this modification to their Big Daddy? I seem to remember seeing this sort of thing done to a Fat Boy.

Thanks,
John
 

astrowolf67

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I have a 29mm Fat Boy that is built this way. The only difference, is I cut the bottom of the cone off, and put a plywood bulkhead/centering ring in. It works great. I've got three flights on G35 Econojets on it, and it's holding up good. The only thing, is people think it's suffered a problem at ejection due to the pop being much louder.
 

ClusterWiz

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The Big Daddy is my favorite Estes kit. I have one that I fly mostly on D12 and occasionally an E15 when I can get one. I bet I have close to around 80 flights on that thing. I have broke 2 fins off once, and used the nose cone from another one that core sampled. But the thing just keeps on flying. Ive built one from scratch lately and used PML tubing and plywood fins and CR. the only thing stock on it is the modified nose cone. I plan to fly it on a H268 or a I200 at LDRS. It has a 13in. long motor tube and only a 10in. body. :D I had to add about 1/3lb. of nose weight. The advice I can give you for a big daddy is to ether cuz the shoulder of the nose cone down to about 1.25in. And of you want superglue a cardboard bulkhead in it, put a screw eye in it and then poor epoxy in it. Otherwise you will have no room for anything else but a plastic chute. Also use Kevlar, cable or some sort of shock cord anchor to the forward CR. then use some other shock cord than what they give you or use a longer piece of elastic in it. If you make these changes you will get MANNY MANNY flights out of it. Good luck!
 

Karl

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I too added a bulkhead to mine , then later converted it to 4 x 24mm motors :p Ill post some pics.

Heres the remains of mine after it had a little trouble with the carpark :rolleyes:
Karl
 

Karl

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And the bulkhead.
-Karl
 

Dbarrm

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To answer your question about the nosecone melting. Id coat it with epoxy to keep the hot embers from touching the plastic.


Dan
 

Karl

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Or line the inside with some Nomex
-Karl
 

cls

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worried about ejection heat & particles on the nose cone?

if you have that much MMT tube, why not put a baffle system in there. how about using a piece of stainless steel mesh, like a pot scrubbie, in the tube. maybe a little CA to hold it in.

or you could get more complicated with some sort of removeable cap on the end of the MMT... probably not worth the weight...
 

rbeckey

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I had modified a Fat Boy with a long MMT to the NC, thinking I would have a type of baffle. The ejection gasses severed the shock cord and/or shroud lines every time. Gave up after four or so launches.
 

grimlock3000

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Built stock, the Big Daddy really is almost all nose cose with barely any room between the motor mount and the huge nose cone. Here are some mods I did to my Big Daddy in an attempt to make it as reliable as possible without getting too complicated. I built up the rocket to be a 24mm workhorse and as a way to get some building experience before I start working on rockets with F and G motors. First, I put a couple of nickels in the NC and epoxied them in place to help with the balance if a larger engine was used. I also epoxied in little pieces of balsa to hold a bulkhead:



Then, I decided to use a flexible metal wire for the first section of the recovery cord. Now I do not have to worry about burning that section of the recovery system. The wire is wrapped around the motor mount and epoxied there, and attached to the wire is a longer than stock section of recovery cord. Also shown is my nylon chute and cut nose cone:



And finally, here is the chute in the body tube, and a good shot of the bulkhead I made for the nose cone. It is just 1/4 balsa epoxied in there with a 75 pound test zip tie for the shock cord attachment point. With this setup, there is a lot of room in the body tube for whatever recovery wadding you want to use:

 

NewEntity1

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Nice pics! I'm comtemplating eventually making a scratch-built rocket that will be an upscale version of the Big Daddy.

It would have a 5.5" diameter body tube, and 3 24mm motor mounts :D
 

jetra2

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Originally posted by NewEntity1
It would have a 5.5" diameter body tube, and 3 24mm motor mounts :D
I can tell you by not even looking at anything but that, that you are going to want a LOT more power than that. You could go with a 4" diameter tube and 3x 24mm mount, but anything over that you'll want 3x 29mm or even 3x 38mm...I'd like to recommend the 38mm's :)

Jason
 

NewEntity1

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Yeah agreed...3x29mm it is. I wouldn't want my 29mm Fatboy to upstage it, after all ;)

Keep in mind that the Big Daddy is a very short rocket however, and will only weigh about a third what a normal dimensioned 5.5" rocket would weigh...heck, it'll be considerably less than 3 feet tall!

At any rate, this project is for...later.
 

OKTurbo

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This is what I ended up doing on my Big Daddy. I'm going to coat the inside of the nose cone with some epoxy to help protect it. I plan on stuffing a 4" square Nomex chute protector in there too to catch the hot globs.
 

OKTurbo

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Here's an overall shot. I covered the fins with some 24lb paper using Mod Podge.
 

OKTurbo

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Close up on the fins...
 

Karl

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Hospital Rocket : I've also converted my Big Daddy to 4 x 24mm power , this babys gonna rock! I'll fly it on the 10th of July hopefully on 4x D12's , or chad each motor to D12-0 <-> D12-5 :D Seeeeeeeeeeya!
Karl
 

OKTurbo

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I finally got some paint on my Big Daddy...

The first picture is with the flash on.
 

OKTurbo

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....no flash....

(Pearl Paint Job)
 

OKTurbo

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Now a shot showing the nifty 24mm retainer midpwrguy made for me.
 

loopy

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Very nice! I love pearl coats! My first BD was black pearl, but the blue looks even better! Great job!

Loopy
 
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