"Strapped" - BT60 4FNC with Apogee Strap on Boosters

[snrkl]

So I have been spending a little more tie then usual on rockets while I enjoy a week of vacation at home with my boys, who are on school holiday, and finally came to the Apogee Strap on Booster set in my build pile.. Lost for something interesting to strap them to, I have opted to (mostly) build the rocket they provide with the Rocksim file for the boosters.. I changes some dimensions and substituted for a BT60 NC I had in the parts box...


Flying wth a D12-7 and a pair of C6-0s, it is simming to ~350m.. JLCR has it landing about 30m away in 15-20km winds with the JLCR set to 90m... (I hate walking...) Rocksim doesn't sim the pod descent at all, so who knows where they will end up...

Primary construction is almost finished (I just have fins to CA edges and attach once their papering is dry tomorrow, launch lugs and the pod couplers to install)

I've been playing tonight with some colour schemes.. I wanted to do something different to what I have done in the past (after all, I have a reputation to uphold! :wink

So here is what I have come up with: Strapped



The boosters kind of reminded me of the SRBs on the space shuttle, which led me to shuttle like white wings with black edges...

I am using an Apogee BT60 eBay kit I bought to suss out how they are constructed.. I won't be using the ebay for anything on this bird beyond holding my JLA3, but the option is always open to use this as a flight computer controlled Dual deploy when I deem the time is right to get my feet wet in that particular pond..

Because I will likely use the eBay on other rockets, I decided to go for industrial looking orange/black stripes.. the plan is to paint in my signature orange and wrap a laser printed black stripe decal around the whole section. That could be tricky, but I'm willing to give it a shot... any hints on methods not to shoot myself in the foot putting on a waterslide decal that wrap a whole tube would be greatly appreciated!

Depending on how the boosters go, I might swap out the booster's stock "very pointy long NC"s with some of the 24mm vacu-formed oblique ones I have in the parts pile.. I think they will look better.. I dry fit them and they are VERY tight - and vacuformed parts cant really be sanded much - they are SUPER thin...

 

[snrkl]

View attachment BT60_with_Strap-on_booster.rkt

Oops - forgot to attach the rocksim file...

 

[Tinker]

I have built the Apogee BT-60 Bay kit with an Ez-Mini and it is pretty nice. Ran thru the tests but have not flown it yet. (its in my Star Orbiter). I like the product.

I opted to mount my boosters with dowels and launch lugs as it made construction much simpler, but mine is slightly different in that it is two stages with a clustered first stage. (Estes Mammoth with PSII booster & two bt-55 strap-ons). I should have pictures by next week.

I cannot say enough nice things about the Estes Boosters that they are selling dirt cheap. If you make your own rockets, using them as fin cans just makes experimenting so much nicer as there is no worries about mounting or sanding fins, no motor mount to construct. Oh I need two boosters, *BAM* that was easy...... Oh I want to test out this baffle design I made in BT-60, *BAM* I have a working rocket assembled in an hour that I care little about if things go south.....

Tinker

 

[Nytrunner]

Is the BT60 ebay like their 1.9" ebay (~48mm)?
I used the 1.9's sled and closure in my PSII transition ebays. I love the thumbscrew attachment for the endcap.

Is your wrapped waterslide shaped like a strip, or is it much wider (more squareish)?
For wrapping waterslide stripes, I let them get very wet, so that they easily slide off with a gentle pull on one end. With ~1/4" (or ~1/2 cm) off the backing paper, I place that end in position on the tube and gently slide the backing with a pull-motion from the opposite end. I try and let the surface tension of the water do the work of adhering the decal to the tube as I go (saves hunting air bubbles later). This usually allows me to completely lay the decal is short time. Any misalignment can be gently nudged into position while it's still wet.
*the only difference I see for much wider wraps is that you'll want to take more care letting the decal adhere to the tube. More room for air bubbles of course.

 

[GlenP]

... paint in my signature orange and wrap a laser printed black stripe decal around the whole section...

It can be hard to paint-match color with a printed decal. Black may be the easiest color to match, but you will have clear decal portions on top of your orange. One technique to get a perfect color match is to paint the decal paper itself, you might give that a try. Print the pattern, apply a glossy clear-coat base, then use that pattern to line up masking tape and paint the orange in between the black stripes.

The decal wrap you are planning is kind of like the Mercury Redstone roll pattern decal:
https://modelrocketbuilding.blogspot.com/2015/07/estes-mercury-redstone-1921-build-part_31.html
just get the body wet under the decal and work around slowly. Your pattern kind of reminds me of the Snipe Hunter, with those strap on boosters you could make that payload larger diameter like that classic design.

I think the water-slide decals are are way easier than peel-sticker body wraps like on the Phoenix Bird:
https://modelrocketbuilding.blogspot.com/2012/05/estes-phoenix-bird-build-part-18-main.html

that snorkel logo is really cool.

 

[snrkl]

The decal wrap you are planning is kind of like the Mercury Redstone roll pattern decal:
https://modelrocketbuilding.blogspot.com/2015/07/estes-mercury-redstone-1921-build-part_31.html
just get the body wet under the decal and work around slowly.

I did large decals on a flat piece of painted furniture for my step daughters birthday last week - I actually used a spray mister to wet the flat shelf surface before application and it worked well - I might try that again...

Your pattern kind of reminds me of the Snipe Hunter, with those strap on boosters you could make that payload larger diameter like that classic design.

We must be related! I was thinking about a larger payload with a transition myself!

that snorkel logo is really cool.

Thank you kindly - much work went into its development!

 

[snrkl]

Is the BT60 ebay like their 1.9" ebay (~48mm)?

I believe it is - here is the one I bought: https://www.apogeerockets.com/Electronics_Payloads/Electronic_Bays/BT-60_Ebay_Kit

 

[BABAR]

Because I will likely use the eBay on other rockets, I decided to go for industrial looking orange/black stripes.. the plan is to paint in my signature orange and wrap a laser printed black stripe decal around the whole section. ...

electrical tape (black easy, but other colors are readily available at least in US hardware stores) works great for spiral wrap arounds because it conforms to the spiral. Disadvantage is it is thicker than paper decal, so not as aerodynamic, but it is really easy to work with.

 

[snrkl]

Still one coat of gloss white owed on the aft section, then I let the paint cure properly till I paint the fin edges and apply decal to the ebay and body.

 

[snrkl]

Decals and pinstripes today...



Used yellow rice paper painters tape - I drew the black fin outlines with a pencil and taped 1mm back from the lines then used an eraser to clean off the pencil, lest the graphite prevent paint adhesion - one super interesting discovery: the eraser burnished the tape down amazingly well - I might use that from now on as the yellow tape is MUCH cheaper than Tamiya tape.

A few small bleeds in the armpits that I'll have to touch up:



While the striped ebay decal looks great from the front, I had seven circles of hell putting it on.

Learning 1: needed to make the decal 1.5mm narrower than the calculated tube circumference - the decal stretched quite a lot.

Learning 2: Two coats of clear wasn't enough - I lost print badly in sections.

I prioritised the smooth application for the front and took the slack around the back of the eBay where the decal actually ended up overlapping by almost 2mm...



All up, progressing nicely.

My local motor provider has even managed to dig me out some b6-0s so I can fly it on the 15th... for some reason Estes BP motors are getting hard to source here at the moment.

 

[snrkl]

Remaining decals done...

Touching up the bleeding armpits by hand with a brush and some "spray in a cup".. once I'm happy, I'll clear coat the decals.

 

[rharshberger]

Turned out great, nice work!

 

[snrkl]

Turned out great, nice work!

Thanks!

 

[neil_w]

Yeah, that really came out beautiful. Look forward to the flight pics!

 

[snrkl]

Yeah, that really came out beautiful. Look forward to the flight pics!

Cheers!

 

[BABAR]

Snazzy. Would make a great kit!
Looking forward to flight report.
straight trails!