Building/modifying a BSD Thor

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lalligood

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OK, I have just received & opened the box to my new BSD Thor. Everything looks great & I plan on taking my time building this beast. I do have a few questions that i'd appreciate some advice on before I start though...

1) The booster tube is 34", the payload sections are 10" & 24", & both couplers are 6" each. I really would like to build this with a single baffle/zipperless design as described in the INFOCentral section of ROL. I'm planning on flying it initially with motor ejection & sometime down the road using electronics for dual deployment. What would be the best way to make sure that I have enough room for all of the electronics and chutes? And what would be the best arrangement of the payload sections for this to work with the zipperless design?

2) Another concern of mine is internal fin fillets. I've used (& am rather fond of) PML's expanding foam but with the split fin design--not to mention 3 centering rings--this isn't going to be (easily) possible. I'm thinking/hoping that the first few flights will be on some combination of Pro38 H153/I205 & Pro54 J210/J295. Any recommendations or is this a non-issue for this kit? (However, fiberglassing is a bridge I'm NOT ready to cross just yet...)

Everything else I feel pretty comfortable with & I've very please with the quality of their parts & instructions. Goodness knows I still might have other questions along the way... That's it for now & this should be quite a fun one to build! :D :D Thanks!
 
If you're going to make it zipperless, here's how I would do it (and would have done mine if I didn't want to fly hybrids):

  • Determine the length of the longest motor you want to fly
  • Cut the booster tube to this length minus 3" so the motor can stick up into the coupler bulkplate
  • Use this extra piece for your electronics bay
  • Use the pre-cut short tube for your drogue compartment
  • Use the precut long tube for your main compartment

Of course, if the cut off length for the booster is something like 2 inches, I wouldn't worry about it and just go with a standard design, placing the electronics in the provided bay. If you're using shorter altimeters (MissileWorks RRC<sup>2</sup>X, PerfectFlite MAWD, Loki ARTS, etc.), they'll easily fit in a coupler and you can epoxy the two bays together to make a vehicle with less joints.

OTOH, I glassed mine and put in a full dual altimeter dual deployment setup along with double tip-to-tip glassing on the fins and major Aeropoxy everywhere else... I like to build em strong in case Frank ever offers me a K1500 or something to fly ;)

Those Pro54s should be great flights in the Thor! Keep us updated on the project. And where's the pics? You have a box of parts to take a picture of, don't forget! :D

Wow, I typed more than I meant to...
 
We do love pictures around here, don't we? Here's what came in the box...since daveyfire asked!

(forgive the pic quality--it's from a web cam that can take still photos. as I get closer to completion I promise to borrow a "real" digital camera!)
 
And after a couple hours of uninterrupted work I'd managed to get all centering rings/bulkheads sanded down & the fin slots cut. Here's a shot of everything "dry fit". (I also stood my PML Phobos next to it as a size reference.)
 
And I want to thank you daveyfire for the advice, however, I think I'm going to just go ahead & build it stock per the instructions... That will still leave me with the path of moving to dual deployment in the future but without the zipperless design on the booster tube.

With a little luck my goal is to have this rocket built & finished (anyone know where I can order Duplicolor metal flake spray paint online??) in time for NEFAR's Bunnell Blast on November 8th & 9th.

I'll be sure to add more pics as I progress in the build as well!
 
Originally posted by lalligood
2) Another concern of mine is internal fin fillets. I've used (& am rather fond of) PML's expanding foam but with the split fin design--not to mention 3 centering rings--this isn't going to be (easily) possible. I'm thinking/hoping that the first few flights will be on some combination of Pro38 H153/I205 & Pro54 J210/J295. Any recommendations or is this a non-issue for this kit? (However, fiberglassing is a bridge I'm NOT ready to cross just yet...)

My recommendation for the internal fins would be to use Polyurethane glue (eg Gorrilla Glue). Put it on the root edge and slide it through the slot and onto the motor tube. Polyurethane glue expands, but takes a while to dry (24-36 hours) in my experience.

I didn't use it on my original Thor build. I won't recommend the way I originally built my Thor (fin attachment) any ways. I am in the process of repairing a fin that came loose from the inside root edge! :mad:

I'm sure you're going to enjoy this rocket. I did... do, will again. my review

Take care.
Nick
 
Lance,

I used Duplicolor metallic anodized blue on my mini-Armageddon. Whe I painted it the nozzle depressed below the spray can rim causing the paint fan to splatter/spatter. I contacted Duplicolor about the problem on their website and they refunded my money for the two cans I had bought. The nozzle is not interchangeable with Duplicolors other paints or any other brand. They didn't seem too interested about fixing the problem but had no problem refunding my money. Be aware that this could happen.
 
Last night was all about doing all the sanding. Tonight has been all about the epoxy. Couplers & bulkheads are complete. Fin can is 75% complete. Everything is going very smoothly so far... (Didn't bring home the camera tonight so I won't have any new pictures for a day or two.)

Swimmer,

Thanks for the information about Duplicolor paint. Bummer... I have had such good result with Krylon in the past but their lack of metallics (other than silver & gold) had me looking to see what else might be out there. Sounds like I might want to keep looking or go with ol' reliable Krylon. :rolleyes:


Nick,

Thanks for the advice about the polyurethane glue. Is that something I can pick up at my neighborhood home improvement store? Any brand(s) that you recommend?

Thanks for the advice :D:D
 
Originally posted by lalligood
Thanks for the advice about the polyurethane glue. Is that something I can pick up at my neighborhood home improvement store? Any brand(s) that you recommend?

Thanks for the advice :D:D

Yes, Gorilla Glue is a brand. Elmers has a poly glue as well.

Gorilla is cheaper (around here).

Nick
 
Over the weekend I was able to get another decent chunk accomplished on the Thor. First was epoxying the motor mount into the booster tube, then attaching the fins. I picked up some 30-minute epoxy to use instead of the 12-minute stuff I already had & was running low on. I think I'm only going to use 30-minute epoxy from now on for large builds. I don't feel like I have to rush when using it & that in turn means that I'm able to do better work. I can also mix up larger batches & not worry about wasting as much either.
Also, BSD recommends using milled fiber (chopped fiberglass strands that almost resembles a powder) with the epoxy for stronger bonds--rumor has it that it makes the epoxy 3 times stronger. I only added the milled fiber for the fin fillets to give them more strength. Another benefit of the fiber is that it makes the epoxy thicker...turning it from a runny liquid into a paste-like texture. This is particularly nice since it helps keep the epoxy right where I want it. I only have 2 pair of the 6 pairs of fillets done so far but the fins with fillets just don't move! I can still flex the fins that haven't had the fillets put on them yet. And even though it's a small container, about the size of a salt shaker, there's enough to last a loooooong time. I'll definitely be using it again in future builds!
Other than that, I was able to drill holes for the rail buttons (I'm not even going to bother with the launch lug--this baby is going to only take off on a rail!), vent holes, and rivets (little removable/reusable plastic rivets to hold the nosecone & payload tubes together until I set it up for dual deployment). Finally, I laid down the first coat of primer on the nosecone & both payload sections. The paint scheme is easy (read: no masking). The NC & payload sections will be solid purple & the booster will be white so there's no point in waiting for the entire build to be complete before starting the finishing process! Besides, what else was I going to do while waiting for the fin fillets to dry?!?

Here's a pic of the first pair of fillets done too.
 
Well, I didn't really take any photos during the painting stages because they were little more than all of the various pieces-parts taped up & in single colors to make them look rather drab...

But with all the painting completed & all *4* sheets of vinyl decals (which IMO are the *only* kind of decals to ever be used on an HPR!) applied, I'm ready to show off the fruits of my labor...

I must admit, I'm pretty proud of how it turned out! Take a look...

BTW, I'm planning on launching it on Sunday, Nov 9th at NEFAR's Bunnell Blast on a Pro38 I205 :D :D
 
OMG...you did it stock colors!!! WAY Cool Lalligood!!!!!

That is an excellent paint scheme and you did well. As far as deploy goes, you can always add it later. I Wish you the best of luck on it's first launch.

Don't for get the launch pics, :)

Carl
 
That is awesome! I really love the looks of the Thor. I may have to get one myself.:)
 
Lance,

Please send me pictures of your Thor's flight. I will put it in a special place on our web site for everyone to see. Something that beautiful must be put on display.
 
I *finally* got to launch my Thor today :D

Original plan was to send it up on a Pro38 I205 using motor ejection (I plan on using it with electronics & dual recovery eventually...) Thankfully I spent time in RockSim to see what delay I'd need with an I285 just in case...and it just so happened that the onsite vendor only had the Pro38 4-, 5-, & 6-grain motors with him, which meant I had to go with the I285--hardly a bad thing if you ask me! :cool: Here's a picture of me standing by my Thor on the pad right before liftoff... (And don't let the smile fool ya, I was nervous as heck! haha)

BTW, NEFAR was the club hosting the launch at a sod farm. Their equipment, location, & hospitality are TOP NOTCH! Check them out if you're ever in the area.
 
I can't say enough positive things about the Pro38 motors. They are just so easy to prep, adjust the delay, & ignite... (OK, so maybe we could wish for more propellants than their classic & smokey sam...but that really doesn't count!)

Here my Thor wastes no time getting off the pad. Also, the split fin design produces a sweet whistle before the motor even finishes burning & lasts several seconds afterwards! It was a perfectly straight flight to ~2200ft.
 
Finally & like I mentioned previously, I was using motor ejection for recovery. The orange chute was immediately visible & opened quickly, bringing the Thor down safely ~1000ft from the pad. Since we were at a sod farm & there is so little (read: none) change in elevation, I watched it all the way to the ground & walked straight to it. Only downside is that it looks like the landing was a little on the hard side...there is a slight kink in the booster tube just above the forward end of the MMT :( A piece of coupler tubing, a little sanding, & some touch up paint & it'll be as good as new! A *very successful* launch in my book! Here's me celebrating the launch...

I would enthusiastically recommend the BSD Thor for anyone considering it for their Level 2. I'll certainly be using it for mine...that probably won't be till March or April 2004, but I'm confident that it'll do just fine!
 
Lance, congrats on the awesome THOR flight! I wish we could have been out there to witness that beast fly. I'm glad to hear everything well. Although the kink might have been minor in your book, I'm sure it burns you up to see the minor flaw. Perfectionists are all the same. ;)

NEFAR is a great organization. I've only been out there twice, but each time was a pleasant experience. Right now our tentative return will be in March. I think Leo will be in the area as well.

Springtime is going to be nuts as we'll be going to the SEARS Alabama launch in February, NEFAR in March, and Whitakers in April. Talk about a busy schedule! If you are interested in caravaning with us to any of these events, drop us a line.

Take care and thanks for sharing!
 
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