Tiamat JB-3 (1st USAAF Air to Air Guided Missile 1:23.5765 MMX Scale Build thread

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Thanks for the Kudo's Tonimus,TopRamen & Pem-Tech!

Wow guys!
I'll try hard not to anger the creatures of the deep! That said; it would be really KEWL to launch this micro model from Wallops Island. Hummm! I may just try to set something up with the Visitors Center as I believe they still do public model rocket launches once or twice a month. LOL, OH Man! now that would be awesome:)

Over the weekend I decided to toss the existing Tiamat wings making a new set where the internal basswood stiffeners are trimmed to make a much better fit. Instead of taking almost 3/16" off the entire outline my calculations indicate I only need to shrink the leading and tailing edges by 1/32". The tip reduction remains about the same 3/16".
On this set I spent a lot more time symmetric airfoiling both sides of each wing leading and trailing edges. The tip to root taper was then added, test fitting often in the process. 67lb cardstock printed skins were carefully cut-out, double white glue applied to each of the internal tabbed stiffereners. I think the resulting new wing set is a much better representation of the actual wing section than my 1st attempt.

Wings than had the control surfaces embossed and hinge balls simulated with half round styrene pieces. After allowing about an hour for the skin & detail adhesive and glues to dry, each wing was white glued into the matching tab slots. With the exceptions of some small 3/32" styrene H- rail lugs & possibly Laminating the inner or outer surface of the balsa transition with High rag content tracing paper I believe consturction is complete.

With everything but the 5" mylar chute installed both conditions were swing tested. I'm happy to report the Tiamat with a single MMX-II motor and the combined Tiamat & Booster with all 8 motors both conditions swing test was instantly positive for the very first beinging of the swing. High Speed and very slow speed both Boosted and Tiamat alone are very stable without any additional nose weight at all.

Speaking of the Launch rail and lugs: I really want to launch this model from a Scale Launcher with Nanobeam rail(s) using Plastruct #90542 3/32" styrene H-beams in place of round lugs.

After closely looking at the 07-04-1945 launch prep photo; I noticed the 1st Tiamat was launched with one Wing & Fin sandwiched between guide rails facing downward. Humm: This may cause my model a little problem depending on where I place the launch lugs or IF lugs are used at all.
If I don't build micro a scale launcher, I could launch this model as is, without lugs from a micro tower or use a single Nanobeam with lugs centered between wing/fins. For now I'm not going to add launch lugs until the final decision is made on launcher type.

At this point I'll let the model sit for a day or two to settle everything than start the finishing process. Already have the primer and yellow paint picked out. Since all the balsa has been pre-sealed with CA I'm hoping a single coat of gray primer will take care of the remaining open grainlines. We'll see when the primer is applied. Regardless the plan is to sand off nearly all the primer to keep the mass down. So far the Tiamat empty mass is 11.4g without finish or 5" Chute. our 7 motor Booster naked empty mass 8.6g. Combined thats an Ewt of 20.0g plus 7 MMX-II-NE and 1- MMX-II at 8.8g we hit the scale at 28.8g. If I can keep the mass down with the Paint those seven MMX-II-NE motors should really give this model a Very Quick boost:


Below are some photos of the new Wing set and the construction completed model including a couple of just the Tiamat. I'm sure it will be perhaps a week before I'll have any more finishing work done on this project. If I start a Scale Launcher I'll update as it goes.

MM 422uc15a_Tiamat Wings Set #2 Basswood stiffeners_08-14-16.jpg

MM 422uc15b_3 Tiamat Wings Set #2_08-14-16.JPG

MM 422uc16a_Tiamat Const. Complete(LeftSide)_08-14-16.jpg

MM 422uc16b_Tiamat Const. Complete(Rear)_08-14-16.JPG

MM 422uc16c1_Tiamat & Booster apart(Rear&Front)_08-14-16.JPG

MM 422uc16c2_Tiamat & Booster apart(Rear)_08-14-16.jpg

MM 422uc16d1_Tiamat Const. Complete(Top)_08-14-16.JPG

MM 422uc16d2_Tiamat Base Const. Complete(LeftSide)_08-14-16.jpg

MM 422uc16d3_Tiamat Const. Complete(LeftRear)_08-14-16.JPG
 
You're well deserving of the praise. The level of detail is fantastic. I've had much less detail on larger scale models. Very nice.
 
Wow, just beautiful. I always enjoy your builds and this one is no exception ! It seems I always pick up a new technique along the way too !!--H
 
A few days ago, both Tiamat and booster were set up and sprayed with cheapy "ColorPlace" gray automotive sandable primer using my tried and true method. 3 wet coats about 5minutes apart when let the model sit to cure until the Sniff Test tells me it's time to sand. Well it's be humid as all gee-wiz the last few days so I've moved on to construction phase of another of the 4 Scale micro models we talked about in another thread. Below is a pic of the Tiamat and Booster in grey primer. looks a lot different then bare tubes and stuff.

more to come later:)

MM 422uc17a_MM Tiamat & Booster Primed 1st -3 coats_08-19-16.jpg
 
Thanks Guy's:
So far the Tiamat and it's Booster have been a lot of fun during the build. Now we're into the part that always seems to take twice or three times as long...the Finishing.
With all that's going on here over the weekend, I doubt I'll be doing any model building at all.

The better 2/3rds and I will be celibrating our 39th anniversary and her Birthday on Saturday with another large family bash so even if I wanted to, it will likely be a good thing I'll not be where I can get to any of the modeling stuff LOL! We'll have to see how clear the head is on Sunday to make any model making decisions;)
 
We are getting close!
Over the last couple days I've sanded the primer with 240 & 320 grit sandpapers to the point I'm satisfied with the surfaces. Used a Needle in pin-vise to re-scribe some of the panel lines and poke the spot weld hole areas. Yestersday the gloss white basecoat was applied. my thought was I'd be doing some sanding or Finesse-it-II applying to get the final surface I wanted. This morning I was pleasently greeted with a white base coat with very few tiny spots that needed to be knocked down.

We're on to the choice of a Yellow color to simulate the yellow on the last example hanging in the Wallops Island Visitors Center. After a couple scrap patches sprayed, I've chosen Rustoleum Rust inhibitor Sun Yellow Gloss. It's a bit darker (and heavier) then all the other yellow on my shelves(6 in other brands). Looking at the purchase date on the can I hope this new can still has propellant enough for the job. It's been sitting on one of my Paint Rack Shelves since July of 2009.

Success! The old can of Sun Yellow worked fine with a replacement nozzle and a Hot water 3 minute bath. Came out fairly thicker then I saw on the patch but seems to have smoothed out just fine. Now we'll see how long it take to outgas. While I was at it I ran & clear coated the tiny little "Tiamat" decals.

Now I can concentrate on just How I'm going to launch this puppy! I've been toying with the idea of scratch building a combo display diorama/ working launcher based on the only single rear view photo I have of the 07-04-1945 perp work. It's small and in black & white making it even harder to distinguish between support member but we'll see which I can come up with. From the photo it looks like the Tiamat & Booster were mounted with a Wing and Fin wedged between two round pipe rails. I sure wish I could get a single side view of this launcher set-up. without that side view I know the contraption was a zero length launcher so I'll be adding some length to it no matter what for launching anyway. Perhaps I'll be able to rig some sort of dual Nanobeam rail to contain the model for the first split second of so.
With 7 MMX-II-NE motors kicking this model in the butt, I think it will be pulling almost as many G's as the original boosters 7200lb if thrust pushing a 600lb missile.

In the next day or so I'm missile and booster will be complete. the Diorama/Lancher will take a little more time LOL!
Here are the progress photos from the last couple days'

MM 422uc17b_MM Tiamat Booster after sanding_08-30-16.jpg

MM 422uc17c_MM Tiamat After primer sanding_08-30-16.JPG

MM 422uc18a_MM Tiamat in basecoat white_08-31-16.JPG

MM 422uc18b_MM Tiamat booster basecoat white_08-31-16.JPG

MM 422uc18c_MM Tiamat & booster basecoat white_08-31-16.JPG

MM 422uc19_MM Tiamat & Booster- Rustoleum Sun Yellow_09-01-16.JPG
 
Over the weekend this vehicle project has been completed. Tiamat JB-3 and it's original 07-04-1945 Wallops Island clustered booster are now ready for flight.

That said: I'm now in the process of building a Scale working launcher diorama. Don't have any photos of the launcher progress yet but below are the last model building photos. Swing Tests have been positive for both the Tiamat single stage with a single MMX-II and 8" drycleaner bag plastic chute. the Tiamat-Booster combination as also been swing Tested positive with the sustainer motor and 7- MMX-II-NE booster motors. I really can't wait to get the model on a launcher. It'll just have to wait for a suitable launch platform or from my micro tower.

I'll add to this thread when I get the launcher/diorama going.

MM 422uc20a_Tiamat & Booster Complete & Scale Data Pack_09-02-16.jpg

MM 422uc20b_Tiamat & Booster Complete Left Side_09-02-16.jpg

MM 422uc20c_Tiamat & Booster Complee Left Side_09-02-16.jpg

MM 422uc20d_Tiamat & Booster Complete Rear View_09-02-16.jpg
 
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Thanks Dick:

I'm working on a launcher Diorama set-up. kind of tough tho as I only have a rear view photo to work from. I should have the model with me at the September 17th Night launch but doubt I'll have the launcher ready.

Below are 3 Tiamat JB-3 & Booster Stat photos just for fun.

MM-422a01_Tiamat & Booster(right)_09-02-2016.jpg

MM-422a02_Tiamat & Booster(Left)_09-02-2016.jpg

MM-422a03_Tiamat & Booster RearView_09-02-2016.jpg
 
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