SR-71 Blackbird build thread - FINISHED

This morning with the glue completely dry, I held up the work in progress and took this picture.



The next step is to glue on the wing sections that are outside the nacelles. I probably could have glued them on at the same time I was gluing the nacelles onto the body, since the double glue method seems to be a really quick and strong joint, but I didn't want to chance it. If a nacelle fell off while I was trying to get the outer wing section on I'd probably say a few curse words.

On a side note, yesterday my two newest rocket kits arrived in the mail from Dr. Zooch. I got a Saturn V and a Freedom 7 (Al Shepard's Mercury-Redstone) from him and am very much looking forward to building both.

Nice job...its looking good!!

Really, really,-- nice so far. U DUN GUD. Ahhhh, a new call sign. It's yours to take------?

Thanks for the kind words! I always like how a build slowly changes from pieces into the correct shape. Obviously that's what we're doing, but it's still neat to see it slowly change - like it's growing or something.

Now that the nacelles had dried and weren't going anywhere I was comfortable enough to start gluing more stuff to them. The wings continue out on the other side while fins (rudders) are glued to the top and bottom of each nacelle.

These pieces of balsa are the first ones glued on that weren't covered with paper, and so these were carefully filled and sanded to make them smooth. I didn't round over the leading edges of these wings yet because I wasn't sure if that would wreck the look or not and decided to ask what other people thought before I did.

Should I round over the leading edge of the outside section of the wing? It won't match the inside section but it might make the flight better.

The double glue method was once again used to get these on.



And after the initial glue had time to set up I gave each side a fillet for strength.



I ended up putting fillets on whenever I could as I glued on other pieces. These wing sections probably ended up getting at least 4 by the time the night's build was finished. I don't know what the limit is but I'm guessing after 3 or 4 you don't gain any significant strength with more filleting. But that's just a guess, I have nothing to base that on. I wonder if anyone has done any testing?

As I waited for the initial wing double glue to completely dry so I could add the fillets I did a little work on the nose cone. It got an all over sanding with 330 grit so the primer would hold better. I also used the hobby knife to trim off a little bit of flashing around the thin edge.

There are 2 eyelets in the nose cone that are filled with plastic.


These needed to be cut out without cutting off the eyelets themselves. The plastic was very thin around the area to be cut but not thin enough to cut with one pass. I had time so I slowly scraped the point of the knife around and around. After just a few minutes they fell out.


Glue joint still wasn't set up completely on the wings, so I kept working on the nose cone.

A little bag of clay came in the kit. Since I'm new at this, and I think this is rocket number 8 for me, maybe 9, this is the first kit that required adding nose weight. I understand the reason for wanting the center of gravity to be further to the front but this seems like such a small weight, it doesn't seem like it would make a difference at all.


I'll trust the engineers at Estes and put the clay in the nose anyway. After cutting the bag open and playing with the clay a little bit, making lewd shapes and giggling at them, I rolled it into two "snakes" as directed.


The instructions say to drop the snakes into the front of the nose cone and use a pencil or dowel to press it into place. None of my dowels were small enough to fit into the hole, and I didn't have a pencil handy, so I grabbed one of my paint brushes that was just long enough to do the job.


The first snake went in all the way and it was a little tricky to get it mashed into place because it tended to stand up and stay on the sides. I kept pressing the paint brush handle in there over and over and I felt like I was churning butter. The second snake was broken into half inch pieces and dropped into the bottom, which make it a lot easier to press them into place.

When I was done I held my camera against the opening and managed to take a picture of the clay in place.


By this time my wings had dried and I put on the fillets that I mentioned earlier.

another option is to use some epoxy after you mash the clay down to hold it in place.

The sheet of card stock that the wing height guides came on also included two guides for the fins. The fins that are glued on the tops and bottoms of the nacelles aren't attached at 90 degrees, the upper fins slant inwards and the lower fins slant outwards. In order to get the angles to match these guides are used to hold the fins against as the glue dries. I'm sure the card stock was thick enough and would have worked just fine, but I just wanted to be sure so I decided to glue them to thicker cardboard.

If Dr. Zooch is reading this thread he might recognize the cardboard I used as a flap from the box he used recently to ship two of his kits to me.


I spread some glue on it very thin, placed the guide in place, waited about 2 minutes, and started cutting. The only critical cuts were along the edges where the wings and the fins would touch. The arc that was cut out to make room for the nacelle was big enough so it wouldn't touch the tube - only those two edges touch anything. I was careful to cut close to the lines all around anyway.


The result is that the guides are a lot more firm, which came in handy as I was simultaneously pressing the glued fin onto the nacelle while pressing the guide firm to the fin to make sure it was at the correct angle.

Here is the guide just sitting on the wing to show how it will work to define the angle of the fin.

As I was placing the guide all around the wings with the fins dry fitted in place and deciding on the best way to use it I began to think about the joint where the fin meets the tube. Gluing a squared fin to a round tube is doable, but I prefer to try and round the edges a little before gluing them. But a squared edge that is leaning at an angle onto a tube just seemed like it would be a really weak joint. Again, I'm just making an assumption about this, I don't have the experience to know that a fin glued like that would come off easier, but I wanted to avoid it anyway. And yes, I know what happens when you make an "assumption". You end up making an ASS out of U and MPTION. Or something like that.

So I put a piece of sandpaper on the table and using the guide as a reference I sanded the edge of the fin to an angle. I wasn't too worried about getting this angle precise, I just wanted it to be close. Anything close would be better than no angle at all.


Luckily I was thinking clearly and sanded the two fins in opposite angles!

After the sanding was done I used the double glue method to attach the fins to the tops of the nacelles.



I'd used the double glue method a lot, and I knew that the fins would stay in position nearly instantly and I didn't have to worry about them moving, but I couldn't help it. I sat there for at least 10 minutes checking the fins with the guide every 30 seconds or so looking to see if the fins were slowly drooping out of position. The double glue method works great and after putting the fins in place they never moved even slightly.

The fins got 3 or 4 fillets on each side before I was done last night.

That was a good move on your part sanding the angle in on the fin...you definitely increase the strength of the joint and lessen the chances of them falling off.

After the fins set up I was pretty happy with the way they looked. And as I was admiring them I noticed that the tube where the motor mount would go was no longer circular, it was oval. The paper that was glued onto each side was pulling so hard on the tubes that it was getting deformed!! The motor mount is glued into the tube near the end of construction for some reason (instead of early on like other kits I've built) and it wasn't in place to help the tube hold it's shape.

I grabbed the motor mount and it wouldn't fit into the tube at all and I got a little worried that I'd somehow screwed the pooch on this one. To get the tube to be round enough to fit the motor mount in I did something that might have been stupid if it hadn't worked. I sat the rocket on the edge of one wing and pushed down on the other, and the tube opened up just enough without me breaking off a wing. The motor mount is in place now, without glue, and maybe it'll be easier to remove and replace with glue when it's time to do that. For the time being it will stick out further than it will when finished. I left it sticking out a little so I'd have something to hold onto and pull when removing it. Whew! Close one.



The fillets in the inside joint was a little more difficult to get glue onto and rounded with a finger, but doable.



I really struggled with when to attach the bottom fins - whether to use the double glue method on them the last thing last night and let them fully dry overnight, or to just wait until tonight to start on them. After seeing that the bigger fins on the top of the plane held their position well I wasn't worried about these falling over, so I decided to go ahead.

But as I went to get started I turned the rocket upside down onto the newly glued fins and realized that it would probably have to sit like that all night. I'm not worried about the top fins shifting under their own weight, but the weight of the entire plane might be trouble. The fillets hadn't even fully dried yet so I changed my mind and decided to wait and start the bottom fins the next morning.

I had one of these kits and noticed in the instruction they had you install the motor mount last. How stupid! Does it really make a difference when you install the mount? Way to Go ESTES! I swear I wonder who the brilliant goober was that decided to write the instructions for this kit.

Looks good my friend ,nice build ! I built this kit a little over a year ago ,and found it very enjoyable and had no troubles whatsoever.

I did scrap the stickers that came with the kit ,and used my own waterslides from my huge stash that i collect for my model aircraft.

You are absolutely correct ,ALWAYS apply decals over a glossy surface...ALWAYS :wink:

I did the same thing with mine ,gloss black ,decals then applied a satin clear coat (flat was too out of scale to me)

I can`t tell you the thousands and thousands of decals I have applied in my day ,and I love it ! You can`t beat that painted on look you get with waterslide decals.The clear coat (flat or satin) really help to blend everything together.

Keep at `er !


Take care

Paul T

sodmeister said:

Looks good my friend ,nice build !

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Thanks!!

I did scrap the stickers that came with the kit ,and used my own waterslides from my huge stash that i collect for my model aircraft.

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I wish you'd kept them!!! I went looking for mine just now to scan in case I messed them up, and can't find them anywhere! I think they accidentally got thrown away during a clean up. This stinks.

I sent a note to Estes asking if they had some I could buy, but since this is out of production I'm not expecting them to have any.

Mushtang said:

Thanks!!


I wish you'd kept them!!! I went looking for mine just now to scan in case I messed them up, and can't find them anywhere! I think they accidentally got thrown away during a clean up. This stinks.

I sent a note to Estes asking if they had some I could buy, but since this is out of production I'm not expecting them to have any.

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But don`t forget ,the stock markings are those peel and stick buggers

That`s why they went to the rubish pile ! After all that work ,this kit NEEDS waterslide decals.

I actually made mine a "MARINES" what if version.....looks cool

I think I have a pic somewhere.


Paul T

Here you go.

MARINES :handshake:


Paul T

sodmeister said:

But don`t forget ,the stock markings are those peel and stick buggers

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Oh really? Eww, I thought they were waterslide decals.

Now I think a trip to the hobby shop is in order, I think they have packs military looking waterslide decals for use on models.

That's a good looking Blackbird you've got there!!! I hope mine comes out half that nice.

Mushtang said:

Oh really? Eww, I thought they were waterslide decals.

Now I think a trip to the hobby shop is in order, I think they have packs military looking waterslide decals for use on models.

That's a good looking Blackbird you've got there!!! I hope mine comes out half that nice.

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You`re already half way there chum :handshake:

I buy a lot of aftermaerket decals from hobbyshops that specialize in models.

Indeed ,I refuse to use those damn "stickers".It would not be so bad if they didn`t have that clear film all around the perimeter ,but still too thick...looks like ca ca poo poo !


Paul T

Mushtang,

Don't worry about parts, decals or whatever. I have a couple kits put aside and may end up sending you one. Great job and great build thread. I cloned this bird 20 years ago using manilla folders for the paper wraps. Worked OK.
I just got the Night Wing kit which uses the same nose cone.
I may do a build thread like yours.
I'm enjoying the build.

Daniel

dlazarus6660 said:

Mushtang,

Don't worry about parts, decals or whatever. I have a couple kits put aside and may end up sending you one.

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Wow, that would be very generous!!

Great job and great build thread. I cloned this bird 20 years ago using manilla folders for the paper wraps. Worked OK.

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I'm impressed by people that can close a model using their own materials and looking at pictures, or however you do it. Being so new to this I'm still amazed when a kit I'm working on turns out correctly. Ha!

I just got the Night Wing kit which uses the same nose cone.
I may do a build thread like yours.

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I wish you would. And take lots of pictures! Every time I post the pictures from the night before I always realize that I missed taking a couple of shots that would help me describe what I'm doing.

I'm enjoying the build.

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Thanks!

RocketManDan said:

That doesn't make any sense ... why not paint it flat black and then dull coat the decals?? Less work same results...but of course if you want to make it hard on yourself

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If you put decals on over dull paint there will be air trapped between the decal and the paint, no way to avoid it since the flat paint is rough. This will make the decal silver, very very noticeable on black paint.

Mushtang is quite correct painting gloss first, then decals then dull coat.

We learned this building plastic models.

gldknght said:

If you put decals on over dull paint there will be air trapped between the decal and the paint, no way to avoid it since the flat paint is rough. This will make the decal silver, very very noticeable on black paint.

Mushtang is quite correct painting gloss first, then decals then dull coat.

We learned this building plastic models.

Click to expand...

Wonderful now I can sleep at night! LOL

Mushtang said:

Now that the nacelles had dried and weren't going anywhere I was comfortable enough to start gluing more stuff to them. The wings continue out on the other side while fins (rudders) are glued to the top and bottom of each nacelle.

These pieces of balsa are the first ones glued on that weren't covered with paper, and so these were carefully filled and sanded to make them smooth. I didn't round over the leading edges of these wings yet because I wasn't sure if that would wreck the look or not and decided to ask what other people thought before I did.

Should I round over the leading edge of the outside section of the wing? It won't match the inside section but it might make the flight better.

The double glue method was once again used to get these on.

View attachment 75468

And after the initial glue had time to set up I gave each side a fillet for strength.

View attachment 75469

I ended up putting fillets on whenever I could as I glued on other pieces. These wing sections probably ended up getting at least 4 by the time the night's build was finished. I don't know what the limit is but I'm guessing after 3 or 4 you don't gain any significant strength with more filleting. But that's just a guess, I have nothing to base that on. I wonder if anyone has done any testing?

Click to expand...

I would have papered them for strength using white glue and printer paper-- MUCH stronger and eliminate the grain in one fell swoop, but that's me...

Looking good! OL JR

Mushtang said:

A little bag of clay came in the kit. Since I'm new at this, and I think this is rocket number 8 for me, maybe 9, this is the first kit that required adding nose weight. I understand the reason for wanting the center of gravity to be further to the front but this seems like such a small weight, it doesn't seem like it would make a difference at all.
View attachment 75472

I'll trust the engineers at Estes and put the clay in the nose anyway. After cutting the bag open and playing with the clay a little bit, making lewd shapes and giggling at them, I rolled it into two "snakes" as directed.
View attachment 75473

The instructions say to drop the snakes into the front of the nose cone and use a pencil or dowel to press it into place. None of my dowels were small enough to fit into the hole, and I didn't have a pencil handy, so I grabbed one of my paint brushes that was just long enough to do the job.
View attachment 75474

The first snake went in all the way and it was a little tricky to get it mashed into place because it tended to stand up and stay on the sides. I kept pressing the paint brush handle in there over and over and I felt like I was churning butter. The second snake was broken into half inch pieces and dropped into the bottom, which make it a lot easier to press them into place.

When I was done I held my camera against the opening and managed to take a picture of the clay in place.
View attachment 75475

By this time my wings had dried and I put on the fillets that I mentioned earlier.

Click to expand...

OH YEAH IT MAKES A DIFFERENCE!!! You'd be amazed at just what a difference a little properly placed weight can make! Adding a little epoxy or a squirt of Gorilla glue and a drop of water (water cures urethane glue and makes it foam up like it should) usually helps... the little extra added weight of the glue not only locks the clay in place so it stays as far forward in the cone as possible and doesn't risk coming loose and dropping to the rear, especially under the gee loads of acceleration, but the additional weight also improves the stability margins...

Don't use TOO much, though... the more weight, the further forward the CG, the more prone to "overstability" and weathercocking the thing will be...

Later! OL JR

gldknght said:

If you put decals on over dull paint there will be air trapped between the decal and the paint, no way to avoid it since the flat paint is rough. This will make the decal silver, very very noticeable on black paint.

Mushtang is quite correct painting gloss first, then decals then dull coat.

We learned this building plastic models.

Click to expand...

what about a Satin Black?

sodmeister said:

You`re already half way there chum :handshake:

I buy a lot of aftermaerket decals from hobbyshops that specialize in models.

Indeed ,I refuse to use those damn "stickers".It would not be so bad if they didn`t have that clear film all around the perimeter ,but still too thick...looks like ca ca poo poo !


Paul T

Click to expand...

You could always scan them in to the computer and print them on waterslide decal paper...

Just have to make sure you get the "scaling" right between the scan and print...

Heck my printer (Dell All-In-One) has a built "copy" feature so I could simply load decal paper in the printer tray and hit "copy" and it should be 1:1 between the stickers and decal paper reprints... assuming there's no "white" ink that needs to be printed (which probably puts the kabosh on the whole idea considering this model...)

Oh well.. just a thought... OL JR

RocketManDan said:

what about a Satin Black?

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Nearly the same effect as going over flat. Lay waterslides over slick gloss and overcoat with flat or satin. I would use satin on this one for scale purposes--but the flat do look good. On a side note--if you were using an airbrush--you might get away with it--because the paint particals are smaller , but you would still have to use a decal solvent to get them to slick out -maybe--and it tends to make decals "really" delicate.

Great build.
You probably already know this, but you may want to consider testing your black paint and your clear coat on a scrap piece of balsa. I was happy with my SR-71 build, paint job, and decals--- right up to the point I clear coated and got orange peel! I am sure it was just inexperience, maybe didn't wait long enough for black paint to cure or put it on too thick, :cry: but it sure bummed me out.

BABAR said:

Great build.
You probably already know this, but you may want to consider testing your black paint and your clear coat on a scrap piece of balsa. I was happy with my SR-71 build, paint job, and decals--- right up to the point I clear coated and got orange peel! I am sure it was just inexperience, maybe didn't wait long enough for black paint to cure or put it on too thick, :cry: but it sure bummed me out.

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GREAT POINT !!