Estes Big Daddy Woes.....& construction tips

I picked up an Estes Big Daddy today with the 40% off coupon from Hobby Lobby and just spent an enjoyable late evening setting up the motor
mount.
However, their directions miss a few opportunities to be better. I've built several Estes rockets over the years and now my Sons are just getting into it, I like to follow the directions and look ahead for potential problems and areas to easily modify for improvement.
It turns out the yellow spacer tube in our kit was either too short or there is a misprint as to where to mark the motor tube. As pictured the motor block ring meets the motor hook but if you follow the spacing and marking procedure you'll end up with those two items about 3/16" too far apart.
Fortunately I realized this before the glue dried and I set up the ring to the correct spacing, while I was at it, I trimmed the motor hook on the drive end in case I ever decide to try a reloadable casing.
One tip I'll pass along- the disc of scrap from the upper motor mount makes a nice doubler for the former where the shock cord passes through. I placed it on the top side where it wouldn't interfere with the fin interface. I also used a section of Kevlar tied to a 1/4 x 9/16" multi-layered ply instead of a lower shock cord, and passed it through the upper motor mount. It's glued in forming the bottom of the sandwich that is ply / former / disc scrap.
Since the fins are laser cut they are very accurate however an opportunity is missed since the instructions don't mention checking the spacing of the two motor mount rings as the rings are being glued in. Once the rings are on the motor tube, I used a fin to space them exactly, then applied the glue fillets to the mounts. The alternative is to roll the dice and hope the motor mounting rings aren't too far apart, or spend time sanding across the grain to shorten them up to fit between rings that are too close.
Now when the motor mount assembly is slid into the body tube, the fins will meet up with the motor tube and upper and lower motor mount rings perfectly. I'll then attach the shock cord to the Kevlar keeping enough space so the Kevlar is taking most of the heat.
Hopefully this will be useful to someone else building this kit someday.
Mike Doyle
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Mike, The Big Daddy is one of my favorite Estes kits. I have an unassembled one I found on the clearance rack at Michaels that I hope to make a 3 24mm cluster with.
Darian
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I like it too and couldn't resist mocking up the components to get an idea of the finished look. I never built one "back in the day" since for me the "D" engine powered stuff was pretty special and out of my price range.
One great source for Estes rockets for our neighborhood was the local JC Penney Outlet Store's, catalog returns dept. Back in the late 70's and early 80's that department consisted of rows and rows of overstock and returned merchandise in plain brown boxes. We discovered if there was a red and white diamond "flamable solid" sticker on the outside of the box, then there was likely a rocket kit inside.
The prices were dirt cheap but it was pot luck on what you were actually buying. I remember getting a Saturn V in one box as part of a starter set, plenty of blast off flight packs and dozens of rockets.
Right now I'm trying to decide if I'll go all out on the finish with filler and clear coat, or make it more of a daily driver. If my local CVS Pharmacy has any of those disposable digital camcorders, I'll hack it, and modify the Big Daddy to haul it.
When you get into your project, post pics of a "how to", I'd love to see them.
Mike Doyle
Darian wrote:

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I don't think I've ever flown mine on a D. Mostly it's been the reloads with my favorite being the F39-6. That tends to get people's attention. I also did not like the standard shock cord arrangement and put a LOC mount near the top of the body tube so I can replace the shock cord any time is shows signs of scorching. I cut a spill hole in the parachute to keep it from drifting so far and may upgrade to a nylon parachute since I keep getting little burns in the plastic ones even with as much wadding as I can cram in.
Larry
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How does the pricing of the reloads compare to stock Estes motor pricing if you compare motors of similar performance?
What reloadable casing could substitute for an Estes' "C", "D" & "E" mounts?
A few years ago our local hobby shop had reloadable motors that appeared to be sized for use in typical C and D mounts, but they refused to sell them to anyone without a certification so I never pursued it. I was in college at the time and couldn't afford much anyway.
Mike Doyle
Larry wrote:

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They don't really compare in performance... RMS motors are much more powerful than Estes BP motors. Reloads for the 24mm motors run from around $12 to $22 a three-pack. The closest comparison would be the 18mm Aerotech "D13" reload, about $12 per 3-pack, but still much more powerful than the Estes 24mm "D12".

Aerotech makes 18mm and 24mm reloadable motor systems, which are the same size as Estes 18mm (1/2A through C) and 24mm "D"-type motors, and will usually fit in motor mounts without any adaptation (some- times it's necessary to file down the forward engine hook a little, for the forward end of the RMS motor to slide past it).

That hobby shop owner is not too bright, to put it politely. No certification is necessary to buy any RMS or single use motor up to "G" impulse.
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Reloadable (metal) casings require you to be "adult" (18 years old).
Casings cost $$$. The reloads are much cheaper than the equivalent single use motors. You simply need to amortize your casing cost over a bunch of flights. After only a few you often hit the breakeven point. If you lose a casing, you will have to buy another and then it will require a lot more flights to reach breakeven.
Online retailers list all the casings, reloads and prices.
The Aerotech catalog lists the size (dimensions).
18mm fits 18mm.
24mm fits 24mm.
29 mm fits 29mm. http://www.aerotech-rocketry.com/customersite/resource_library/AT_OrderForms.html http://www.aerotech-rocketry.com/customersite/resource_library/Catalogs_Flyers_Data_Sheets/2005_aerotech_catalog.pdf
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I forgot a link:
http://home.flash.net/~samily/stuff/HPR_metric8.pdf
And note that the Aerotech order form clearly spells out the are requirements for G motors as well as any power level of RMS motor.
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Great info, thanks guys!
I'm hoping for some calm weather here in Kansas over the holiday so we can do a few launches.
Mike Doyle
Fred Shecter wrote:

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