BT-5 Downscale of classic rockets

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gpoehlein

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OK - I'm gonna start re-building a thread from TRF v1 - the BT-5 downscale thread. I'll put my downscale wraps here and others can put anything in here they think fits as well (Have fun, Bob!)

I've built several, and they fly great on mmx motors - not too high but still fun. You could also power them with 13mm motors, but I wouldn't go much higher than 1/2A if you want to get them back! ;)

Here is a photo of several of my BT-5 downscales, along with a LPB for scale.

When building these, I recommend printing the page on Business Presentation paper - it is usually about 32# and semi-glossy. Print at 100% with NO scaling. I paint the nose cones with Tamiya Gloss Acrylic - it levels pretty good and gives a nice glossy finish. Finally, if building the mmx version (and even if not on all but the mosquito), I attach a shock cord of kevlar thread to the nose cone and make them nose blow recovery. You can add a streamer if you like, but they don't go that high so you shouldn't lose it. (Use a streamer on 13mm motors!)
 
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How about a full scale mosquito? Just add nose cone.

I'll post more later as I get a chance and build some more.
 
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I scaled down a LOC Lil' Nuke (I called it the REAL Lil' Nuke) to BT-5 and I used an Evil Ed resin nose cone. Lost all the pics when I lost my old work laptop, but I'll post it back up when I get it painted.
 
I didn't realize it until the build was complete, but the BT-5 Blue Ninja
is essentially a Gnome!

(In best Church Lady impression) - Well, isn't THAT special!!! :D

Seriously, nice job on the downscales - That Ninja does look great!
 
keep them coming you have me wanting more balsa hehehee and bt5
 
keep them coming you have me wanting more balsa hehehee and bt5

Actually, I glue two layers of 110# cardstock together for the fin core, and then wrap the fin outer layer around that. Balsa tends to be a bit thick for these little guys, especially if you add the fin wrap. If you try the cardstock core, I recommend rotating one layer 90 degrees from the other to minimize curling (you are essentially creating a paper ply similar to plywood - plypaper if you will ;))

I've got a couple others that I've done the pdf for, but haven't had a chance to build yet. Just a teaser:

Zoom Broom, Groove Tube, Star Speeder and Colonial Viper :p
 
For the cardstock models I've done, I use 4 layer 110lb cardstock for the fins. They will still soften if under the direct summertime Arizona sun or trunk of a car (learned that the hard way) but are easily straightened once cooled and reheated with either hair dryer or heat gun. I think the 4 layer allows a much wider area of contact to the BT as well as added strength w/out a ton of weight. If you were to do a 3 ply cardstock fin and the side wraps, that should be plenty of strenght for any 13mm motor.
 
OK - I'm gonna start re-building a thread from TRF v1 - the BT-5 downscale thread. I'll put my downscale wraps here and others can put anything in here they think fits as well (Have fun, Bob!)

I've built several, and they fly great on mmx motors - not too high but still fun. You could also power them with 13mm motors, but I wouldn't go much higher than 1/2A if you want to get them back! ;)

Here is a photo of several of my BT-5 downscales, along with a LPB for scale.

When building these, I recommend printing the page on Business Presentation paper - it is usually about 32# and semi-glossy. Print at 100% with NO scaling. I paint the nose cones with Tamiya Gloss Acrylic - it levels pretty good and gives a nice glossy finish. Finally, if building the mmx version (and even if not on all but the mosquito), I attach a shock cord of kevlar thread to the nose cone and make them nose blow recovery. You can add a streamer if you like, but they don't go that high so you shouldn't lose it. (Use a streamer on 13mm motors!)

Greg:
Just be sure to remind folks BT-5 is really the outside end for Micro powered models unless Clustered. Even rolled paper or cardstock in BT-5 and up models, given the added frontal area severally limits altitiude and performance on Micro motors. They're fine if your just wanting to covert that favorite Standard size model to mini motors but Micro's really need a bit thinner airframe;)
Love the paper wraps for mini motor use tho:)
 
Greg:
Just be sure to remind folks BT-5 is really the outside end for Micro powered models unless Clustered. Even rolled paper or cardstock in BT-5 and up models, given the added frontal area severally limits altitiude and performance on Micro motors. They're fine if your just wanting to covert that favorite Standard size model to mini motors but Micro's really need a bit thinner airframe;)
Love the paper wraps for mini motor use tho:)

I think you just did, John! ;)

Seriously - I like flying these guys on MMX motors - they are true backyard rockets. Granted, they don't go very high (50-60 feet maybe), but they are still fun, and it isn't like you have to worry about them thermalling away! :D I haven't weighed them in a while, but it seems to me that even with the heavy plastic nose cones and Estes BT-5, they don't weigh a lot more than 9 or 10 grams. They certainly fly better than the LPBs! And the parts are easily available to most everyone who has a Hobby Town, Hobby Lobby or Michaels nearby. Not that I am disparaging ordering T2, 2.5, 3 and 4 parts to build smaller, better performing rockets (heck, Jim's MMX kits are awesome!), but these lumbering hulks are neat and a whole lot of FUN!
 
I have a few that are just rolled cardstock. Most use the plastic cones from the Estes bulk pack or the 220 Swift cone.

All of these fly on MMX motors and are great for the back yard.

1. Alien Space Probe - Mosquito cone.

2. Goblin - Quark cone.

3. Mini Bertha - Mosquito cone. This is actually a downscale of a downscale.

4 & 5. Nasa Pegasus - Quark cone. This is a 3 motor MMX cluster.

These all can be found on the Ultimate Paper Rocket Guide

The body tubes are rolled 65 lb cardstock with laminated cardstock fins but I suppose they could be stretched slightly and made into wraps instead.

MicroPegasus_1.JPG

MicroPegasus_2.JPG
 
A couple of these are a little bigger and too heavy for MMX but make great 13mm motor models. The Starblazers could be made for MMX but I use 13mm motors in mine.

1. Orbital Transport - Quark cone. The cardstock glider actually glides very well and I've almost lost it several times so I only fly it on 1/2A3-4T's now.

2. E.S.S. Raven - This has a cardstock cone.

3. U.S.S. Atlantis - Quark cone.

4. Starblazer - Quark Cone. Estes reused the Starblazer name a couple of times.This is a later version.

5. Starblazer - Quark cone. This is the earlier version.

raven1.JPG

Atlantis 001 (2).JPG

StarBlazer_1.JPG

StarBlazer_old1.JPG
 
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A couple of these are a little bigger and too heavy for MMX but make great 13mm motor models. The Starblazers could be made for MMX but I use 13mm motors in mine.

1. Orbital Transport - Quark cone. The cardstock glider actually glides very well and I've almost lost it several times so I only fly it on 1/2A3-4T's now.

2. E.S.S. Raven - This has a cardstock cone.

3. U.S.S. Atlantis - Quark cone.

4. Starblazer - Quark Cone. Estes reused the Starblazer name a couple of times.This is a later version.

5. Starblazer - Quark cone. This is the earlier version.

Bob,

Love the OT. I have done many of those and have gotten great glides from the glider. Heck, even published the plans in Aunt Effie's Cabbage Patch (our club news letter) back in the 1980's :)

Here's a pic of mine, along with several other 13mm downscales.
 
Really cool looking downscales, I'll have to print out and build some. What glue do you use to attach the body wraps?
 
Really cool looking downscales, I'll have to print out and build some. What glue do you use to attach the body wraps?

Plain old Elmer's white glue. Just make sure you spread it REALLY thin, and get it lined up right - once it grabs, it won't let go.
 
It almost seems possible to print out the bt wrap on label paper and make it peel and stick. Of course you would loose the glossy look.
 
I had a Blue bird zero donwscale. Sorry, no pics.

I gotta remember: camera [sutter] button before launch button!!

Decals came from Phred..

(Oh, and a BT-50 downscale of a BBZ is a sweet rocket too!! not to big, not too small.. perfect for a C6-7!)
 
Here is my 13mm Blue Bird Zero from Bob's downscales
mini-bbz.jpg
 
It almost seems possible to print out the bt wrap on label paper and make it peel and stick. Of course you would loose the glossy look.

Don't see any reason why you couldn't - You can always give it a gloss coat after you finish.
 
I built a couple of these downscales using the documents that gpoehlein uploaded. They make very easy builds, and should fly great. For almost zero cost you can easily build these rockets, and they look good. Not exactly the correct cone on the Alpha, buy hey it was in stock. Gluing the wrap on with Elmers was a pain, however using some spray 77 contact cement on the Alpha made it a simple task. For the fins I used 1/32 basswood that worked out great.

Nice job GP, thanks for uploading the artwork!

DSC00103.jpg
 
My standard Photon Probe cradles its BT-5 downscale counterpart.
PP100.jpg
 
I did a cardstock downscale Patriot complete with cardstock nose cone which is a bit rustic but not too awful for a first attempt. Uses 13 mm motors.
View attachment 157112
 
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Nice job, Rich! How did you make the nose - a series of transitions or closed petals?
 
That's what I use in all my card stock models as well - I never could get the "closed petal" method to work for me. I have a spreadsheet that I plug any number in for the front and rear diameters and the length and it calculates the ID , OD and arc of each transition. I then draw those in Adobe Illustrator. Its a bit more work, but the advantage is that I have the conic wraps as raster images and I can then color them or do anything I want to them easily. Where it really shines is making roll patterns on transitions - tough to get just right in a paint program, but rotating lines in Illustrator is a snap.
 
Bumping this Thread. Saved the Bobs Downscales Site to my Favorites.
Cool Thread!!!
 

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