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Funkworks

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Step 60dot6Clockwork.jpeg

Handy: TA-DA!

Clumsy: Hey! That’s Clockwork Smurf!

Sassette: It’s NOT a REAL Smurf!

Handy: It rusted over time so I had to resmurf most of it.

Sassette: Can it talk?

Handy: It only makes noises. Someone at SURFAS is smurfing some code to teach it how to work!

Clumsy: Gosh, what do they need it for?

Handy: They didn’t tell me.

Sassette: Can it walk?

Handy: Not yet. We have to carry it to the launch site so it can be smurfed. Let’s go!

Sassette: Can it dance? Hee! Hee! Hee!

And as they made their way along the fence from the Smurf X rocketshipyard to the SURFAS launch site, Handy noticed a bright red door leaning against it.

H: Say Clumsy, did you guys get to smurf all the outer boards today?

C: Yeah but don’t touch! I had to wash up 4 times. They say it could take a few days to dry and we have to smurf another coat.

H: Rust-Oleum’s Gloss Apple Red?

C: You got it!
Step 61 Red Paint First Coat.jpeg
 
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Funkworks

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Step 61 - First Coat of Red on the Boards

Here’s what the boards looked like after the first coat (That’s probably one of Clumsy’s falls).
Step 61b.JPG

To make sure paint reaches all the edges with the upcoming coating 2, I spread them out (keeping their same relative positions) Don't mind the huge pieces of masking tape covering the door's 2 eye screws.
Step 62.JPG

Also, Grouchy Smurf practiced drilling holes for the “landing springs” in the trailing edges of the fins, but it was a lot of trial and error with a 7/8-inch Forstner bit and a 3/4 -inch hole saw, both along the grain and across the grain of leftover 1-inch thick balsa.

Result: The Forstner bit doesn’t “bite” when you try to drill along the grain, which is what I unfortunately have to do here. (Didn’t predict that when I started.) The bit drifts sideways.

Solution: Will get a 7/8 hole saw and slowly drill along the grain. At least the bit will stay along the same axis and not drift randomly. I’ll use clamps to prevent the wood from splitting. I’ll just chisel out the chips out of the hole.

Grouchy: I hate the “error” part of “trial and error”.
IMG_1515.JPG

Meanwhile at SURFAS:

Sassette: Handy, why is that smurf sitting in the middle of the field?

Handy: Must be a rocketry thing Sassette. But I think he’s Clockwork’s new boss.

Master Builder: Looks good Handy! Bring it over to Laptop Smurf, he’ll smurf over from here.

Handy: Alright. Now let me know if there’s anything else I can do. This Clockwork 2.0 model is guaranteed for 3 smurfs!

Laptop.jpg
 

mbeels

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Oh no, who put Clumsy on paint duty? Actually, nevermind, that is probably the best rocketry related task for Clumsy!
 

Funkworks

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Oh no, who put Clumsy on paint duty? Actually, nevermind, that is probably the best rocketry related task for Clumsy!
What I think happened is that Clumsy was the first brave soul to see what Astro was up to in the first place, so when Astro left for his flight training, he put Clumsy in charge of building the rest.
 

mo2872

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Poor SDM(Smurf Decision Making) skills on Astro Smurf’s part.......we sure he’s up to smurf this space shot?
 

jqavins

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Result: The Forstner bit doesn’t “bite” when you try to drill along the grain, which is what I unfortunately have to do here. (Didn’t predict that when I started.) The bit drifts sideways., he’ll smurf over from here.
Are you using a smurf press? I've never heard od a forstner bit smurfing if you've got a smurf press to use it with.
 

Funkworks

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Are you using a smurf press? I've never heard od a forstner bit smurfing if you've got a smurf press to use it with.
Nope! But see my next post. It could be that my Forsters are borrowed and worn, and my hole saws are brand new.
 
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Funkworks

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Step 62 - Drilling the Landing Spring Holes

A few corrections in the numbers:

1. There’s a total of 67 boards that have to be glued to the rocket (7 x 3 x 3 = 63. Less 3 because 3 columns have only 2 boards, so 60. And then add the 7 ones forward of the fins). The length for many of them is based on what’s visible in the comic panels. For those that aren’t visible in the comic, or that aren’t consistent across the panels, I used my best judgement for a random look. If we include the 5 boards that make up the door, there’s a total of 72 boards. ANYHOO.

2. The other number I need to correct is the spring size and hole for it.
  • The spring diameter is 13/16”.
  • The Forstner bit I tried is 3/4” (12/16”) diameter, but it drifts sideways, mostly because the balsa fin is too fragile for me to push hard on it.
  • The hole saw that worked, after drilling a few pilot holes with increasing sizes, is 3/4”. The hole is just deep enough to hide a spring extremity.
So yeah, Grouchy succeeded in drilling the 3 shallow holes to fit the landing springs. The first one is a bit rough, but the others are fine. This was somewhat delicate because they happen to be exactly on the line where an extension is glued to the fin (see my post #1), and the spring diameter is very close to that of the fin width (3/4” vs 1”). Precise measurement with a ruler and a regular pencil was enough though. Clamped the fins a bit while drilling to prevent splitting, and rotated pretty slowly.

Now was the right time to drill these holes it because they should be painted red along with the fins and boards.

Grouchy Smurf:
I hate the first hole, but I hate the other two much less.
Fin Spring holes.jpeg

And at the SURFAS launch site (the other side of the fence):

Sassette:
What a smurfy-looking rocket! Hihihihi!

Laptop Smurf:
Good news Handy, I made a few flight tests using Jokey and Papa Smurf’s new propellant and my model reached an altitude of 2000 apples!

Handy:
Woah! Well if any smurf can launch Farmer’s old silo, it’s them. Papa told Jokey if he agreed to behave in the lab, he’d get to blast Astro up into the smurfosphere. So now Jokey’s serious like he’s never been before!

Laptop Smurf:
Jokey sure knows his way around ignition systems 🎁.

Clumsy:
Uhhh… And Papa sure knows how to smurf things up! 📚🧪💥

Handy:
… and I sure don’t want to be smurfing nearby when Astro launches. It’ll smurf more than a refreshing breeze this time!

Laptop Smurf:
Breeze… right… well … umm... Clumsy? As Vice-President of Smurf X, shouldn’t you be supervising?

Clumsy:
Uhhh… Gosh! You bet I should!

... Golly! I gotta go!
Laptop.jpeg
 

Funkworks

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Step 63 The Second Red Coat

Feathers:
Good-looking boards fellows! I can see them from pretty far away!

Handy:
Feathers! You’re back! But where’s Astro?

Feathers:
He’ll be fine but I left him home to recover. That last parabolic flight was a bit too much - he got sick and passed out. But lucky for me, he was wearing that dumb bubble helmet, so I’m clean as a whistle!

Mopping Smurf:
The boards are dry and we sanded the tube so now it’s up to you Clumsy: either we start gluing the boards to the tube, or we first paint it red.

Handy:
Wait! I’m going to draw a few alignment lines on the tube before gluing anything. Then we’ll glue the boards and if the tube shows through anywhere, we’ll smurf a tiny brush to make touch-ups.

Clumsy:
Uhh… Yeah!
Step 63 Red Coat 2.jpeg
 

Funkworks

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And at the launch site:
Laptop andClockwork.jpeg

Laptop Smurf:
Ok Clockwork. Now it’s just you, me, and Master Builder’s smurfitectural plan. Let’s get this upload going!

< ... taps a few keys ... >

⏳

< ... waits a while ... >

⏳

< ... 🤨 … >

< ... waits another while ... >

⏳

< ... sighs ... >

⏳

< ... sings:
🎼 La! La! 🎶 Lala! La! La!” 🍄
🎼 La! Lala! 🎵La! La!” ... >

⌛

Ready! ... Smurf on wood …

< clicks mini-mouse button >
 

Funkworks

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At the SURFAS launch site:

Master Builder:
Don’t blink Farmer. The specs on Handy’s new Clockwork model are unbelievable.
64a SURFACE 03 Clockworks Before.jpeg

And a surprisingly short time later, the dust cleared and Farmer dropped his rake in amazement.
64b SURFACE 04 Clockworks After.jpeg

Laptop smurf:
BUILDER!!! ... 'LOOKS LIKE WE HAVE THAT BLAST SHELTER !!!

(These are:
- “Creatology Foam Project Bricks”, that were on sale,
- glued together with “Aleene’s Original Tacky Glue” on a balsa and basswood base,
- primed with Krylon “Craft Foam Primer”, and
- painted with Krylon “Natural Stone Textured Finish Granite”.
So this model is not actual reliable to protect PVC figures from a real model rocket launch (D'uh). And it’s “scratch-built, but it’s not a rocket, so it didn’t seem appropriate to spend much time explaining the steps here. Clockwork’s role ends up being to do the entire build in a single step so as to get back to the rocket ASAP.)
 

Funkworks

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Step 65 – Gluing on the boards
(step numbers are based on a personal drafting document I keep updating and correcting)

First, I centered the board over the door (board “1T” for “Column 1, Top”). Using a cheap flexible plastic ruler, I measured the distance from the left edge of the board to a line on the tube I had done earlier when making the fin slots. And I did the same for the right edge, holding the board in place.

Second, I tried using a small T-square to make sure the board was parallel to the tube’s axis, but ended up eyeballing it. Since the rocket has 3 fins, there ends up being 3 independent inter-fin surfaces. The other 2 surfaces are independently aligned (so one misalignment would not mess up the entire surface). The boards making up the columns where the fins are will be custom sanded to fit between the adjacent boards and the fins.

So for each of the 3 inter-fin surfaces, there’s a top center-board and all other boards are aligned around it, and the few boards forward and the around the fins are custom cut and sanded to accommodate the fins and fit with each other.

Here, Clumsy is making sure random gluing weights don’t fall off while the glue dries (long-nosed vice-grips, 2 small wood clamps driving the 2 door-hinge eye screws through the balsa board, a tall flashlight, a tape measure and two small packs of nails). With the regular wood glue I’m using, I wait at least 10 minutes before gluing the next column. Clumsy is finding out that his supervising duties aren’t to be taken lightly.
65a Gluing on the Boards (weights).jpg

Caretaker taking care of a fin-adjacent board with a chisel. (The fins will be in direct contact with the cardboard tube, not with the boards as in the comic or cartoon.)
65b Chiselling a Fin-Adjacent Board.JPG
 

Funkworks

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Almost done with the rocket's 67 surface boards and I'll have pictures soon.

While the glue was drying, I got to finish this side-build which I think will allow a few pictures I have in mind that should be fun. I glued the pre-balsa popsicle sticks from my page 1 posts of this thread, inside the SURFAS Blast Shelter to serve as flooring, and I'm impressed by how wood stain can make them look like a credible hardwood floor.

Here, Builder and the carpenters are celebrating the great job they did.
SURFAS Shelter hardwood floor.jpg
 

TSMILLER

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I don't know what the "real job is....." However if it isn't in creative writing or cartooning models I think you have missed your calling!
 

Funkworks

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Without going into details, I’m an 80’s sci-fi fan who studied physics and now works at writing about science, engineering and technology. I come here to mash it all up without (or little) restraint.
 

Funkworks

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Step 66 – Carving the Boards Around the Fins

Astro:
ALRIGHT GUYS! TIME to CRANK this THING UP! … TEN! … NINE! … EIGHT! … SEVEN! …

Clumsy: Uhh...

Sassette: You don’t even have the pointy top on!

Handy: You ok Astro?

Jokey:
HeArgh! He-argh!! Argh! Let’s DO THIS!

Master Builder:
NOT NOW JOKEY!!! Go back to Papa with that thing!
We still don’t have a nose cone, no landing gear, the motor mount is only half done, no door, no chute…
Oh why do I even bother...

66a Upright w Boards. jpg.jpg

Lots of sanding and chiselling to make the last boards fit against each other and to make sure the fins could fall off smoothly. Still not sure how the fins will perform on the way up though. I see lots of rattling in their future. But not sure it matters.

Fin specs I'm aiming for:
When landed, the fins have to support the rocket.
When launching, the rocket has pull up the fins.
The fins are removable when the ejection charge goes off.

Not bad so far, but I might still have to tune the fin attachment method.
66b Boards via Fins.JPG

Astro:
It all looks good to me!
 
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Funkworks

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67 - Handy’s Fin Release Invention

It took all of Handy’s brain power for a while, but here’s what seems to do the trick.
67-Fin Release v2.jpg

Context:
  • Fins must be 1 inch thick and shaped as in the comic.
  • Fins must be light and wooden, balsa being the preferred choice.
Problem:
  1. Due to balsa being fragile and model rockets often breaking a fin, a fin of this model "must" be detachable.
  2. A fin must be pulled up by the tube at launch time.
  3. The 3 fins together must support the rocket from the springs at their tips when standing on display, for months or years at a time.
Solution:
  1. A stick inside the main tube holds a fin in place until the ejection charge blows off the nose cone, which pulls away the stick, releasing the fin.
  2. The stick passing through a loop on the forward part of the fin root prevents it from peeling away during the ascent phase. In this case, the loop is a length of pvc piping.
  3. The stick passing through a loop on the back part of the fin root prevents it from spreading away from the back end of the main tube, when the rocket stands on display. In this case, the loop is a round staple, bent at each ending, and secured with JB weld epoxy, and upcoming CA.
A tab and a slot, based on what is seen on conventional model rockets, serves to align the fin but could be dispensed with if the first pvc tube extended along most of the length of the fin root.

Another building option would be to have an upper loop and a lower loop, each of which could be a short length of tubing, or a staple. This could decrease the overall weight.

Once the epoxy is dry, I’ll spread CA all over the balsa fin’s root “face” to ensure that it maintains integrity over the winter months while standing on a shelf.

Handy:
It’ll take months before we know if the fins stay on when they’re supposed to, and Korolev-cross away when they’re supposed to. But for now, I don’t see any obvious remaining problem.

Astro:
I like it!
 

mbeels

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I like it! I think you ought to enlist a dedicated photographer for your launch to capture the entire spectacle on video. And I want to see if the Smurfs survive.
 

jqavins

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It's a nifty scheme, and I like it. But...
Not bad so far, but I might still have to tune the fin attachment method.
There's an engineering saying, or rule, or something. Imagine that the thing you're working on fails; what's the first part you'll look at? If you have a ready answer, check it now.

I get the feeling you're not completely confident about the fin attachment and detachment. And, meaning no insult, I'm not either. May I suggest building a test bed? A quick and dirty build with the same mechanism so you can see how it performs before putting this marvelous piece of model building and imagine on the line.
 

mo2872

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Or, rig a ground test stand, and fire it at no flight risk. Proof of concept firing without having to build a whole other test rocket?(I too would hate to see this go badly)
 

Funkworks

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It's a nifty scheme, and I like it. But...

There's an engineering saying, or rule, or something. Imagine that the thing you're working on fails; what's the first part you'll look at? If you have a ready answer, check it now.

I get the feeling you're not completely confident about the fin attachment and detachment. And, meaning no insult, I'm not either. May I suggest building a test bed? A quick and dirty build with the same mechanism so you can see how it performs before putting this marvelous piece of model building and imagine on the line.
I'd rather have an eye-screw than a staple, but I don't have the right size with me, so it's on my week's shopping list. That's easy to add and will improve solidity for little cost.

The part I'm not confident about is how much the fins will "flutter" during the ascent. For high speed rockets, it can be disastrous. But maybe this thing has so much drag that it won't go fast enough for fluttering to be a problem. I'll obviously start with a low-powered 29 mm motor. Also, I don't know the full weight yet so it's hard to simulate and choose a proper motor. Hopefully, the nose cone, the lathe and I will all get along and I'll get to tune the weight to something acceptable.

But yeah, "not completely confident" about an engineering problem is very fitting and also a great and fun place to be.
 

Funkworks

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Step 68 – Waiting for the Last Red Coating to Dry on the Fins

On a slow day at the rocketshipyard, Grouchy waits for the last coat of red paint to dry on the fins before he can install the rocket’s landing springs.

Grouchy:
I HATE having to wait for red paint to dry on fins before I can install the landing springs on a rocket.
68 Drying Fins 3.jpeg

And down below, in a corner of the rocketshipyard, Clumsy sees Master Builder unloading a strange and confusing box.

Clumsy: What’s in there?
Builder: It’s to go.
C: Go where?
B: In there.
C: Whenever?
B: There you go.
C: Uhh... now?
B: Why not!
C: Ok! ... Here I go!
B: Not here! THERE!
C: Oh right, well ... THERE I GO!

B: ... you don’t have to shout about it...
 
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Funkworks

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Step 69 – The Eyes Screws Holding the Fins against the Rocket when its Landed

And when Clumsy got out of the mysterious box …
F05CB78A-C65C-44C7-B9F0-55BCA5F2A2EB.jpeg

Clumsy:
Uhh Papa Smurf! What are YOU doing there? I mean ... here, I mean uhh... in your home...

Papa Smurf:
Ah! Clumsy! I see you found my SARDIS machine! It’s for travelling through Smurf And Relative Dimensions In Smurf! An old friend wanted me to do a few test runs with this prototype. It has all the same capabilities as the full-size version but only a few options are unlocked so we don’t get lost!

Clumsy:
Gee Papa Smurf, I thought it was a tool shed!

Papa Smurf:
Say Clumsy, since you're here, could you bring this book to Astro? He was looking for a way to exterminate termites and this might help.

Clumsy:
Uhh... Sure Papa Smurf!

Papa Smurf:
Just push back on the same lever to smurf back to the yard!

Clumsy:
Ok Papa Smurf!

Jokey:
You have 10 seconds to leave before I smurf my next ground test Clumsy! Yargy! Yarg! Yargy! Yarg! Yarg!

And at the rocketshipyard, Grouchy is now waiting for the epoxy to dry around the eye screws that will hold up the rocket when it’s landed.
69 Drying Eye Screws 856kb.jpg

Grouchy: I HATE waiting for epoxy to dry around the eye screws that hold rockets together!
 
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