Holey Fins & Tranny's Batman!

That red fin can is quadruple-awesome, love the canted cluster. 3D printed? Where's the rest of the rocket?

That blue one looks great too but can't make out all the details in the sea of blue. Got any other pics?

Scotty Dog said:

This is a tranny kinda? Going in the other direction...

Couple designs...Oh did I say..."I like Fat-bottomed Rockets" :lol:
And, Il stretch it a bit more and throw in me "Razors Edge" for inclusion into the "Holy Moley Fin design"

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Ehhhhh...SD, those look more like a tail cones...of sorts. Your Razors Edge, on the other hand, clearly belongs with us up here in the Holey Moley clouds.

Awesome fins and trannys guys!!!
It's great to see some unique designs. It seems that 80% of rockets are just 3-4 FNC, and that just does nothing for me most of the time, with few exceptions.
Throw in some transitions however and it has my attention!
Back to back transitions, or some of the stuff you folks have posted in this thread, now that really gets my juices flowin'!
I've been playing with paper parts a lot lately, and really enjoying it.
Sure, I've done a few TLP kits with the paper hat and tail cone, and a few scratchbuilds with tail cones, and one with a transition, but my current project has me making a lot of these paper parts, and now even oblique cones for boosters.

Anyhow, something I thought I could add to this transition mayhem, is that recently I began lightly sanding the paper parts before shaping them or doing anything. I tried this assuming it would make the CA penetrate in a much more consistent manner, and it has worked perfectly.
I hate it when I make a decent paper part, then, when I coat it with CA, I still have dry spots, squigglies and/or runs.
On the next transitions I'm about to cut out tonight, I am going to gently sand the paper before I even cut the parts out. That should make them perfect, as they were great yesterday and today, but I sanded them after cutting them out, and it was awkward to hold the paper and sand it without damaging it.
I want to see how the finishing epoxy soaks into the paper when it is prepared in this fashion too, versus when it is not gently scuffed.
It is apparent and well known that they, the cardstock manufacturers, spray coatings on the paper, to keep it bright and protected.
I don't know why I did not think to scuff the surface on both sides earlier, but it does make life so much easier, and makes me love paper parts that much more.

I'm in Paper Part Heaven now!!!:clap::clap::clap::clap::clap:

TopRamen said:

Awesome fins and trannys guys!!!
It's great to see some unique designs. It seems that 80% of rockets are just 3-4 FNC, and that just does nothing for me most of the time,
:clap::clap::clap::clap::clap:

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Ain't that the truth! Sure, I have a couple of 3 FNC's around collecting dust, but designing and building "model rockets" (not flying motor housings) is what works for me. Most everything in my fleet looks different and some have a performance factor. Not just how high or fast it went. I get big kicks when my MODEL rockets fly straight up and land without breaking. Having to spend the entire day prepping 2 flights and tracking said "Boost Beasties" down in the back of a jeep just seems all wrong to me. I can knock out 10 flights or better on a good day at the sod field.

Bottom line, I'm all about the design and build. Thanks for the comps TOP el Ramano!

TopRamen said:

Awesome fins and trannys guys!!!
It's great to see some unique designs. It seems that 80% of rockets are just 3-4 FNC, and that just does nothing for me most of the time, with few exceptions.

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I agree in general. I would say that one you're working on now is about as far from 3-4 FNC as you can get. (and it is awesome BTW)

Anyhow, something I thought I could add to this transition mayhem, is that recently I began lightly sanding the paper parts before shaping them or doing anything. I tried this assuming it would make the CA penetrate in a much more consistent manner, and it has worked perfectly.

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Please spill some more detail if you would be so kind. What weight cardstock are you using, what grit sandpaper, and exactly how do you soak the paper in CA exactly? I do not recall having seen this technique photo-tutorialed before.

neil_w said:

I agree in general. I would say that one you're working on now is about as far from 3-4 FNC as you can get. (and it is awesome BTW)



Please spill some more detail if you would be so kind. What weight cardstock are you using, what grit sandpaper, and exactly how do you soak the paper in CA exactly? I do not recall having seen this technique photo-tutorialed before.

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Thanks!!!

Fair enough. I don't want to hijack your thread, so I guess I can start a "How I Am Doing Paper Transitions and Paper Cones", thread.

I'll have to take pictures, and remake a few of the pieces I've already made, I I do enjoy making the paper parts, so it sounds doable. I have to make like two to three of most paper things and eight or more for some others to get it decent for my current build anyway, so a show of what I've learned will just be an aside to my SA-5 thread, but about the paper parts, and not the whole rocket.

I'm using 110# Cardstock from Walmart. It is like $4.95 for 100 sheets, and I can get a couple of months enjoyment out of that.
It does not ALL go to cones and trannys, as I like to print my final draft Openrocket PDF plans on it, and use it for things like checkerboard bands and such. Sometimes I guess at the dimensions, and/or try a few, so some of it gets assembled and then thrown away.
Sure it would be great to save even the ones I may never need, but after all, I can just make another whatever in little enough time to make it worth doing. Lately, I have been cataloging all the transition templates on a USB stick drive and making an extra print to keep with the design portfolio.



I'll go ahead and get on that tomorrow. I need to go cut some paper now as a matter of fact, and get my eye's away from the computer.

Oh, and I used 150 grit to sand the paper.

Started taking pics' tonight for the paper stuffs thread.




Dry Fit:

Gary Byrum said:

Ehhhhh...SD, those look more like a tail cones...of sorts. Your Razors Edge, on the other hand, clearly belongs with us up here in the Holey Moley clouds.

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Ya,ok. I knew it was a stretch. I fixxy it.

Scotty Dog said:

Ya,ok. I knew it was a stretch. I fixxy it.

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Really nice looking tail cones though.

I went back and dug up an old bone I buried a few years ago which really gave me a tranny challenge. This old "APRO Lander" was designed for looks mostly, and it flies pretty good, but I hate that I used a BT-50 where the chute goes. PITFA! Gotta be a 55 or better to keep me happy. Anyway, I didn't have a decent pic showing all three trannys, so I'm using a sketch. The pic is what it looked before I botched the paint & decal job. I don't even wanna show you that. The bottom transition is a BT-50 to 6". The big tranny is a 6" to BT-80 and the upper tranny is an 80/50. If I ever decide to rebuild this, I'm using a BT-55.



It really doesn't look bad with just a white primer coat.

Gary Byrum said:

View attachment 286088

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Whoa, that is by far my favorite thing I've seen in this thread. I have *many* questions about its construction; did you ever put together an OR sim for it? Would I assume a 24mm mount for that? Looks like a base drag machine.

neil_w said:

Whoa, that is by far my favorite thing I've seen in this thread. I have *many* questions about its construction; did you ever put together an OR sim for it? Would I assume a 24mm mount for that? Looks like a base drag machine.

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Nah, I'm too old school for OR or Rock Sim Neil. I do use Autocad though. I really don't need a piece of software robbing me of my gut instincts on stability and such. Besides, I never could figure out how to draw with it accurately. CAD was easier and I already knew how to use it. The rocket does rely on base drag for the most part. I'm sure those software proggys would say it's over stable, but that kind of analysis doesn't concern me. I build a lot of stuff that's over stable on purpose.

Use your imagination and ask yourself, "Where are all the CR's located? Could I just run the BT-50 straight to the top?" That's what I did essentially, and stacked all the trannys on it. If I go to a BT-55, I'd prolly do the same thing and just shove a 24mm motor mount in it. It only flew on a C motor because of the small area we had to launch it in. A D motor might give it a good ride, or better yet, an Areotech E-20 or F-30.

Is the big transition from one piece of paper (if so how big)? Are those some sort of reinforcements I see in the photo at the root of each fin?

I'm gonna have a go at an OR file for this. I wouldn't be worried about stability here with all the base drag, but it's a great way to plan the construction and, more importantly for me maybe, test out paint schemes. Should be fun. I really love that design and am thinking hard about building it (not right now but never too early to start planning).

neil_w said:

Is the big transition from one piece of paper how big)? Are those some sort of reinforcements I see in the photo at the root of each fin?

I'm gonna have a go at an OR file for this. I wouldn't be worried about stability here with all the base drag, but it's a great way to plan the construction and, more importantly for me maybe, test out paint schemes. Should be fun. I really love that design and am thinking hard about building it (not right now but never too early to start planning).

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The fins are a single piece of balsa with a hard dowel railing across the top of each of them. The fins go through the shroud and have some inkling of epoxy or glue at the root. Those pieces around the fins where they meet the shroud are a customized muscle (if you will) to help reinforce the fins and more importantly, cover up the shoddy slots I cut into the shroud. They were way too wide, so I covered them up and made them look like they belonged there. They do serve their purpose. The fins are pretty stout. I'm drawing the BT-55 version as we speak and I'm sure it would be an easier build having learned from this one.

The big tranny was from 4 pieces of copy paper done with the VCP shroud maker. I cut them apart, taped them together in the shape of the shroud and traced the whole thing on some light weight poster board. Thicker than the 110# card stock but not like that heavy poster board stuff. I don't remember the paper weight, but it worked superbly. With that weight of paper and more attention to construction, I should have a beefier version that could take on an E or F motor. I'll post the plan with dims shortly.

Very cool, thanks.

Two files. One has the measurements and a see-through. You should know where you'll need CR's. Trannys can be made on VCP site. The big one prints 3 pages (spits out 4 pages..?#?$?%?$?#) Cut these apart and tape together and trace to thicker paper. 3 trannys in all, and all necessary dims are there so you can print them. The other page is full of templates and they are to scale. Fins, muscles (2 to choose from) and nose cone template. I had to turn my own on the last build also. I don't know if a reasonable facsimile is available online at one of the sites. You'll have to research. Sandman surely can make you one if he still does that. Haven't seen him in a while. If you can't find him, I'll email him and see if he still makes custom nose cones. I don't do nose cones for anyone but me so please don't ask. If you decide to build it, we're gonna want a build thread.

View attachment APRO Lander 55.pdf

View attachment APRO Lander Templates 55.pdf

I'll fiddle with this in OR for a while and see what I come up with. If I build it it'll probably end up a bit different but not too much because I like it a lot the way it is.

After staring and staring I finally understand that the dowels are separate from the fins. I thought they were purple decals on the white fins.

Last time, I had the whole thing assembled before I put the fins on, so I know there was only so much glue at work there. Next time, I figure I should be able to install them before I mount the aft tranny. At least I'd have some fillets in there. And btw, it doesn't matter to me if you wanna change things up on the design. It won't be the first time someone did that. Maybe you can take it beyond where I did and improve it. And if you make an ork file on it, how about turning that into a PDF so I can look at it.

My first quick cut in OR. No centering rings yet.

Sims to 345 feet on a D12 and 6-something on an E15. It's draggy. Don't know if the sims are accurate on something like this, though. 600 feet might be plenty for a rocket like this anyway.

Any thoughts on paint job?

Gary Byrum said:

Nah, I'm too old school for OR or Rock Sim Neil. I do use Autocad though. I really don't need a piece of software robbing me of my gut instincts on stability and such. Besides, I never could figure out how to draw with it accurately. CAD was easier and I already knew how to use it. The rocket does rely on base drag for the most part. I'm sure those software proggys would say it's over stable, but that kind of analysis doesn't concern me. I build a lot of stuff that's over stable on purpose.

Use your imagination and ask yourself, "Where are all the CR's located? Could I just run the BT-50 straight to the top?" That's what I did essentially, and stacked all the trannys on it. If I go to a BT-55, I'd prolly do the same thing and just shove a 24mm motor mount in it. It only flew on a C motor because of the small area we had to launch it in. A D motor might give it a good ride, or better yet, an Areotech E-20 or F-30.

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Thanks for posting this.

I've been building and flying Model Rockets since 1988,(ETA: OOPS!!, actually since 86' according to the stamps on the back of the Kodak 35mm Prints. ) on and off yes, but I learned all about stability as a youngin'.
When folks here question my methods,... Well, let's just say, "Them's Fightin' Words!!"
Sometimes I won't do a build thread simply because I already know what the Sim Nazis are going to wet their pants about.
One summer, when I was like 11 or 12, I had over 300 launches of stuff I made out of the THREE Estes "Designers Specials" Parts Sets.
Yes, I had a couple interesting flights, but always sticking to the things I learned in whatever the Estes Fan Club was called, they all got swing tested and were mostly stable.
I had more problems from stupid rubber shock cords and plastic parachutes than I ever did from stability miscalculations.
When I built my first 29mm rocket in 1999, I did not have any guidance. I did not even know you could get 29mm composite G motors, but when one showed up in the local hobby shop, I bought it before I even knew what I would fly it in. The owner said he had ordered it for a customer who never came back to pick it up.
It was a single use Aerotech G40-7 with no thrust ring, and I had not built a rocket in a few years, but I took one look at the thrust curve and knew exactly what I had to do.
I ordered more motors, and that rocket ended up flying 3 times successfully before I put a G80 in it and it landed in the trees.
Around that time, it was actually rocketry that made me want to start using the internet, and that's how I learned that Aerotech also made Kits.

Even that G-force could be flown around trees safely 5 times before it landed in them a second time, where the Chainsaw was not an option.

neil_w said:

Any thoughts on paint job?

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No. But I sure like that nifty pic you made.

TopRamen said:

Thanks for posting this.

I've been building and flying Model Rockets since 1988, on and off yes, but I learned all about stability as a youngin'.
when folks here question my methods,... Well, let's just say, "Them's Fightin' Words!!"
Sometimes I won't do a build thread simply because I already know what the Sim Nazis are going to wet there pants about.

I had more problems from stupid rubber shock cords and plastic parachutes than I ever did from stability miscalculations.

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Screw the Sim Nazis! They're just jealous. I got my start back in the mid-late 60's, and we were building homemade rockets in my 1st year in the hobby. My dad prolly made the first tube finned rocket and that thang they call "The Decafinator", he made one much the same way back then. Long before anything like them ever hit the market. Yeah, learned stability the real way. 95% of these ppl in here couldn't build a rocket without software anymore.

Thinking about having Stickershock23 make some decals for that model. I'll bet it could be really nice. By the way, where the heck did you put a launch lug on that thing?

In the meantime, I'm considering tranny-fying the other design I'm working on. Dunno if it properly qualifies for this thread or not (also it's not actually built yet, but that's a minor detail :wink:


I definitely seem to be drawn to fins mounted to transitions.

neil_w said:

Thinking about having Stickershock23 make some decals for that model. I'll bet it could be really nice. By the way, where the heck did you put a launch lug on that thing?

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Oooooh yeah. I forgot about that little detail. Just like I forgot to install one before I finished building this bird. For the sake of keeping one straight enough, with the off-beat installation I had to do, and the fact that I didn't know where to get a 6+" length of lug (at the time) I had to roll one from copy paper and thinned white glue. You'd be surprised how durable those are.

The lug had to pass through two trannys and either 2 or 3 CR's. Hard to remember now since a lot of my builds are based on a simple drawing and laced with certain custom details along the way. I basically had to drill from the top of the big tranny (next to the BT-80,) until I was clear of the forward CR's. Using a long pointy object (my indispensable ice pick) I was able to poke a pretty good hole in the aft CR and pass through enough to mark the aft tranny where I had to drill again. Yes! That was a pain in the azz! Keeping my fingers crossed and with the help of a pretty long homemade sanding rod, I was able to get the lug in place. Sure, there's a lot of unglued area on the lug, but there's enough to work just fine. I'm really glad you asked about that. You may have a better location for a lug if you install it before you finish the build. Probably run with 2 lugs on either end of the BT-55, but still hidden behind the forward and aft trannys. At least you will have the ability to cut lug holes in your CR's before you glue them in. I had to use a long lug because I didn't have a choice. It needed to be that way.

I just printed off the shroud patterns and templates sheets Friday with intentions to rebuild this rocket. Would have been a real bummer to had forgotten the lug again. But I really don't have that problem these days. Btw, This rocket was built 5-6 years ago. I'm lucky to be able to remember what I did.

neil_w said:

That red fin can is quadruple-awesome, love the canted cluster. 3D printed? Where's the rest of the rocket?

That blue one looks great too but can't make out all the details in the sea of blue. Got any other pics?

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I guess I missed this...Thanks..you can check them out by visiting the link below..."Temple Of The Dog". The "Temple" is not up to date, but it does have some of me builds. And somewhere in the TRF cosmos, there is/are build threads.

Scotty Dog said:

you can check them out by visiting the link below..."Temple Of The Dog".

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Most impressive, some fine tube cutting work there. Hard to pick favorites, but I'd go with 5-55 and Crystal Flame. Makes me wanna up my game!

Another idea I got stuck in my head. Almost a remix of other of my designs (I need to get out of my box at some point) but still neat. I call it "Launch Lug Nightmare":

You guys are true craftsmen! I have a lot of clones I've built because, like you, I'm attracted to transitions and complicated designs. It struck me as I reviewed old kit plan (I'm not that creative on my own!) that there were two schools of design at Estes back in the 70's and 80's- absolutely bat-**** crazy-awesome (like Estes Andromeda) and those that should be banished from existence (3FNC like The Scamp...I built one anyway, because I had the parts, but I wrote in my build journal how much I actively hate that rocket). Now us kit builders are able to get some wild stuff from other places, Jim Flis, Pemberton come to mind, I'm sure there are others, but the organic process I see here is inspiring. Will have to see if I can get some creative juices flowing myself.

neil_w said:

Another idea I got stuck in my head. Almost a remix of other of my designs (I need to get out of my box at some point) but still neat. I call it "Launch Lug Nightmare":

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MY GOODNESS! If you build that, you'll have me "out-tranned" by a long shot! I can see this is a series of duplicate transitions stacked on what appears to be a BT-55,(gotta love them 55's) NOW, wanna up your game a little and magnify the difficulty level about 5 times? Incorporate a different size tube in there somewhere. Maybe between the two lower trannys and /or, the forward section at the nose cone.

Gary Byrum said:

MY GOODNESS! If you build that, you'll have me "out-tranned" by a long shot!

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Number of rockets I have built to completion so far that include at least one paper transition: 0. I think your lead is safe. Heck, I'm not sure if I'll ever catch up to anyone that's ever built even a single Dr. Zooch kit. Building this *would* however earn me a merit badge in advanced launch lug installation.

I can see this is a series of duplicate transitions stacked on what appears to be a BT-55,(gotta love them 55's)

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I was prepared to ascribe mystical psychic powers to you for figuring out the body tube size... until I just noticed the engine peeking out the back.

NOW, wanna up your game a little and magnify the difficulty level about 5 times?

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Not really. But go on...

Incorporate a different size tube in there somewhere. Maybe between the two lower trannys and /or, the forward section at the nose cone.

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I thought about that briefly but didn't get a chance to play around yet. This was just me jotting down a thought. This design will need a lot of work before it would ever have a chance of getting built, but it seems like a nice starting point.

Seriously, though, the launch lugs... :bang:

I like the backgrounds you used....it really makes the rockets look nice and adds to them.

neil_w said:

Number of rockets I have built to completion so far that include at least one paper transition: 0. I think your lead is safe.

Seriously, though, the launch lugs... :bang:

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Read what I said carefully. "If you build that (snip) out-tranned" You'll have more trannys on ONE rocket than I ever put on one rocket.......I think.....

Yeah, those lugs iza gonna beez you major pain in the Big BooTae!