Skunk'd!

[mbeels]

I decided I'll attempt air starting motors for my next rocket. A 29mm motor in the center would be ignited on the pad, and the two outboard canted motors would be air started.

Skunk

• mbeels
• May 20, 2019

I also wanted to do oblique nose cones. I couldn't find any for BT-60 tube, so I made some by rolling up paper and mounting it to a coupler. I smeared a dollop of 30 min epoxy mixed with phenolic micro balloons on the side, so I could sand a rounded tip and the nose cone would have some strength.

P5021145

• mbeels
• May 20, 2019

The central shock cord will be replaceable, so it runs through a small tube and loops around the end of the engine mount.

P5071211

• mbeels
• May 20, 2019

The canted motor mounts were tricky, plus I wanted to do through hole fins. It took some measuring, but mostly a lot of TLAR, but I got two canted mounts that are nice and symmetric.

P5071212

• mbeels
• May 20, 2019

P5071214

• mbeels
• May 20, 2019

 

[BABAR]

Cool design!
Is there a point in canting the outboards? Will that cause more of a problem if one doesn’t light or less?

 

[mbeels]

Thanks!

Yes, I did it for two reasons, visual effect, and to minimize the steering effect if only one outboard motor lights. If the thrustline of the canted motors goes between the CG and CP, the rocket has the best chance of going in a straight line. It might fly with a slight skew (pointed off to one side), but hopefully maintains a trajectory up.

 

[mbeels]

Through hole fins took lots of filing, sanding, and fenageling, but finally happy with the fit.



I want to keep the bottom of the rocket light, so fins are 1/8" balsa, but I'm framing them out with 1/8" hardwood. Basswood, I think.

 

[mbeels]

I've never papered fins before, but after reading about that technique here, I decided to give it a try. I smeared on a very thin layer of white glue and stuck down a sheet of plain copy paper. I then squeegeed out as much glue as I could with a plastic ruler, and then ironed them down with a monokote iron. That worked super well, I got the paper very flat, and could iron out any warping. So now the fins are very light, stiff, and smooth. I'll do this more in the future.



Ahhh... a chance to see what the framed up rocket looks like. I cut out a transition from a cardboard cereal box. High power is impressive and all, but I have more fun seeing what I can do with white glue, wood glue, balsa, cardboard, and mid power motors.

The side pods have shock cords attached to bulkheads that block the motor ejection of the side motors. The side motor ejections will vent out the side, and electronics will deploy the main parachutes from the top half of the side pods.

The electronics will mount in the space between the central BT-60 and BT-80 tubes. The central motor will eject a drogue out of the central tube. Next up is filling, priming, and painting.

 

[mbeels]

I'm SUPER happy with the way the papering worked out. Wow, they're strong, stiff, light, and finished quickly and easily. Just a single coat of sandable primer, and they look ready for painting. I'll be papering more fins from here on out.

I'm not as thrilled with the joints between the body tubes. I added some extra filler there, and I'm calling it good enough.

This one gets rail buttons and a 3/16" launch lug.

Now, how to paint it.... I need some inspiration....

 

[mbeels]

Well, still no inspiration for a color scheme, or even what colors to use. Usually by now I've got some kind of vision in my head. Maybe it will come. For the time being, I'm going to plow forward. I gave it a starting coat of a pale yellow from my stash of partially used rattle cans.



Now, from this point forward, it is all improvisation. I know roughly where I want the electronics, and I know I need to deploy parachutes out of the side pods, as well as air start the side motors. There will be some details to work out as I go.

First a new #11 blade for the Xacto knife. Onward....

 

[neil_w]

Those oblique cones came out really excellent.

 

[mbeels]

Thanks! Not much progress tonight, but got the inner (stuffer tube) capped off and sealed up, plus framed the opening with 1/4" balsa.

 

[mbeels]

Alright, I think I have a cosmetic vision for this rocket. Inspired by this post, I want this rocket to look like a well used and somewhat abused utility rocket. Along that vein, instead of hiding the wiring, or tucking it away neatly, I'm going to make the conduits visually prominent.

I'm unsure how to do the wiring for the side pod electronic ejection, however. I need to be able to load the ejection charge from the top (via the oblique nosecones), and the electronics are in the center. Hmmmmmm.....



Screw switch installed.

 

[mbeels]

I did not like that terminal block sitting there in the middle of the body tube. I replaced it with one on each side. I also painted the rocket a satin color that I like better. I'll cover this with a hammered metal finish, and then weather it to reveal red and yellow beneath. Maybe it'll look alright, maybe it'll look awful.

 

[mbeels]

Yes, just the kind of effect I was looking for. A well-used, somewhat abused transport craft that has been in and out of many atmospheres. Operated by a curmudgeonly old captain, with a skeleton crew, and not enough funds for anything cosmetic, but the mechanic knows every nut and bolt. That type.

After a few coats of the yellow, I applied one coat of red, then a light coat of a hammered metal finish, and finally a light misting of yellow again and just let the breeze blow it onto the high edges. Then I went to town with some steel wool.

 

[Rockyt]

In this case, What can Brown do for you.....Is NOT a question I wanted answered!

 

[mbeels]

Two day delivery to the moons of Jupiter??

 

[jqavins]

That looks really terrifically terrible.

Suggestion: paint the conduits in a different color, as if they are an addition or kluged repair. Maybe the same grey as PVC conduit in the real world.

 

[mbeels]

That looks really terrifically terrible.

Suggestion: paint the conduits in a different color, as if they are an addition or kluged repair. Maybe the same grey as PVC conduit in the real world.

Thanks, yes, it was fun to do an ugly, dirty, rust-bucket rocket after aiming for "nice" finishes on other rockets.

I like your idea of the off color conduits, I'm going to add a few conduits to the opposite side, to balance out the drag, and clutter up that side of the rocket some more.

 

[BABAR]

Actually I was thinking when you said you were going with external conduits of a steampunk theme, but it didn’t go with the lemon yellow color you started with. I think steampunk would work well with your cool outboard nose cones as well.

 

[stealth6]

I rather like this, yes I do.

s6

 

[jqavins]

When someone comments that the rocket looks a bit beat up, just reply with obvious but contained resentment in your voice "You think paint is cheap? Oh, it's all well and good for you high priced spaceliners to keep everything pretty, but I gotta run on a tight budget or I go outa business. She's passed all her inspections, and good looks don't make her fly any better."

Incidentally, Neil, when I stated in our previous conversations that I sometimes like to have a little bit of a story to help design the look of a rocket, this is exactly what I was talking about.

 

[neil_w]

Incidentally, Neil, when I stated in our previous conversations that I sometimes like to have a little bit of a story to help design the look of a rocket, this is exactly what I was talking about.

Yup, I get the idea it is just not one of my core competencies.

This one came out great. My biggest suggestion would be to photograph it in front of a more contrasting background (vs. the yellow-ish walls and brown molding which is amazingly similar to the color of the rocket).

 

[mbeels]

Actually I was thinking when you said you were going with external conduits of a steampunk theme, but it didn’t go with the lemon yellow color you started with

Yeah, that yellow is a rather harsh contrast for a real steampunk theme. I'm sprinkling the rocket with some 2-56 nylon screws to add more texture, and maybe invoke a little more steampunk feel.

I rather like this, yes I do.

s6

Thank you!

When someone comments that the rocket looks a bit beat up, just reply with obvious but contained resentment in your voice "You think paint is cheap? Oh, it's all well and good for you high priced spaceliners to keep everything pretty, but I gotta run on a tight budget or I go outa business. She's passed all her inspections, and good looks don't make her fly any better."

Incidentally, Neil, when I stated in our previous conversations that I sometimes like to have a little bit of a story to help design the look of a rocket, this is exactly what I was talking about.

Yes! and a half-burned cigar hanging out of my mouth with a scar on my cheek. I like the rocket to seem like a character from a story as well, in which the mechanic does most of his work with an angle grinder and welder.

This one came out great. My biggest suggestion would be to photograph it in front of a more contrasting background (vs. the yellow-ish walls and brown molding which is amazingly similar to the color of the rocket).

Thanks, I've got some decals coming from Stickeshock23, and there are still some more cosmetic details in the works. But yes, I agree, it'll need a better photo!

 

[jqavins]

[T]he mechanic does most of his work with an angle grinder and welder.

While smoking said cigar. "Fuel, schmuel, it aint killed me yet," says Eight-finger Harry.

 

[Bat-mite]

This is a really neat concept and great execution. Can't wait to see flight video (hint, hint).

 

[mbeels]

While smoking said cigar. "Fuel, schmuel, it aint killed me yet," says Eight-finger Harry.

This is a really neat concept and great execution. Can't wait to see flight video (hint, hint).

Thanks, John. I've got some ideas for air starting configurations, it'll fly down at MDRA, hopefully this year, maybe I'll see you down there.

 

[mbeels]

I caught up with the Skunk'd crew at the exclusive resort destination on Titan. They were unloading food and consumables for the first class passengers of the Deep Space Transport which arrived a few moments later.



After unloading and accepting their payment in precious metals only, their departure was delayed due to repeated unstarts in the port engine. Finally, they found the defective valve and improvised some replacement gaskets using the tough grassy leaves now found on the terraformed equatorial regions of Titan. It'll probably last long enough to get back to home base. Probably.

 

[mbeels]

Well it hasn't flown yet, but I hope to get it into the air next week. The longer it sits on my bench, the more I want to add. It isn't easy doing "ugly". I don't want "crappy ugly", I'm trying to go for "Gnarly ugly". There is a fine line between crappy and gnarly. With more inspiration from @Mugs914 ( I like his style), I found some black anodized aluminum tape, and copper tape, and added some patches to the rocket. I also used some very thin wall aluminum tube to add a contrasting exterior conduit.

 

[neil_w]

I was a little unsure what you were going for early on, but man this thing looks great. If we end up meeting at RadRocks in a couple of weeks I hope you'll bring it along.

 

[mbeels]

I was a little unsure what you were going for early on, but man this thing looks great. If we end up meeting at RadRocks in a couple of weeks I hope you'll bring it along.

I was also unsure what I was going for! In hindsight, I probably wouldn't have chosen that combination of colors, knowing now where I ended up.

Yeah, I'll bring it along, RadRocks is only two weeks away! I see the website posts a Go-NoGo the evening before, hopefully things work out.

 

[BABAR]

One additional cool thing about this rocket, unless it totally crashes, the usual scuffs and scrapes encountered from flying it will only make it look BETTER!

 

[mbeels]

One additional cool thing about this rocket, unless it totally crashes, the usual scuffs and scrapes encountered from flying it will only make it look BETTER!

I hope! It will certainly be free of ANY oh-man-I-just-did-the-perfect-paint-job-and-I-don't-want-to-ding-it-up-now pre-flight anxiety.