Estes Orbital Transport, Kit #K-42, Finished

Another crossed off the list!
I've been wanting to build the Orbital Transport for a few years.
If an O.T. is at a club launch, I always watch the flight.
A classic kit, well designed. The only negative thing is too many fins to cut out and fill! The clean decal treatment really makes the model.

Estes Orbital Transport, Kit #K-42, Part 22, Booster Decals

Again, the decals are arranged tight on the backing sheet.
Cut slow and carefully so you don't go into another decal.

The side stripe decal is narrow and long!
You'll have to trim so it fits tight over the front canard fins.

The inset picture shows a pencil line right above the rear edge of the canard fin.
For an easier transfer, the decal will be cut on this line and the two pieces joined.

The front half was applied first.

The rear half is applied and butted up against the front end.
Sight down the rocket body from the front to check straightness.

My home print ASTRON AEROSPACE LINES decal was set back slightly for better spacing around the door decal.


Sight down from the top to align the two name lines.

The nose cone decal went on easier than the glider cockpit decal.

Estes Orbital Transport, Kit #K-42, Part 21, Booster Decals

Double check the scramjet decal positioning before the transferring onto the model.
You would think the small end of the trapezoid shapes would face forward, but the wide end faces the front.
The applied decal (above) is correct.





Before soaking, dry wrap the decal around the BT-5 scramjet tube.

Notice the ends and where they are placed evenly on each side.





Here's the bottom view with the additional decals on the scramjet housing cover. The red stripe ends wrap over and down the sides.






There are large decals on both sides of the main fins. This is something you wouldn't see in a modern kit, coverage on all sides.

Estes Orbital Transport, Kit #K-42, Part 20, Orbital Glider Decals

Looking down from the top, the second "Astron Aerospace Lines" decal was placed.








Normally I can coax a decal around a nose cone. Here I'm rolling a wet Q-tip over the decal to work out the wrinkles. Not this time!

I had to make a small slice with a new razor blade on the wrinkle. This allowed a little overlap and it flattened out. Usually you can only slit a smaller decal.

I use Sharpies, a lot!
I used a wide soft point marker for the inside and a finer point pen for the edge trim. I may have to go back over the edge with some white to clean things up.

This did seem to give a dark black, when I take it out in the direct sunlight I'll be able to see how opaque it is over the white paint.

Done!
Well, the orbital glider anyway.

Estes Orbital Transport, Kit #K-42, Part 19, Orbital Glider Decals

The gloss white finish coat on the glider was dry before the larger booster assembly.

The Semroc Orbital Transport decals (and maybe the original Estes kit decals) are tightly arranged on the sheet. Look how close the glider decals sit next to the long red booster stripe decals.

You might have to use a sharp knife before trying scissors.







I set the tail section decals on first - no problems so far.

The "Semroc Astronautics Lines" decals were cut off for my home printed "Astron Aeronautics Lines" decals.

Sight down the front to be sure the decal base is in a straight line. That tapered tip can easily slide up and down. This red decal actually sits a little below the center line.

Here's the replacement decal. It ended up the same size as the original. On this side, the "A" in Astron lined up with the start of the rear, red taper.

The front of the tube isn't bent down, that's just some distortion in the image.

Estes Orbital Transport, Kit #K-42, Part 18, Scramjet Assembly Gluing

Yep - I should have glued these scramjets on earlier, but I wanted to get enough white paint into the inside edges. There are a lot of inside areas on the model.

Some paint had to be removed for gluing.
The scramjet assemblies were set in position then slide back about 1/16". The fronts of the housing vanes were marked.

The marks were made 1/16" back so there wouldn't be a chance of scraping too far forward.

The aluminum angle was used to extend the pencil lines to the back, parallel to the body tube.
The angle wasn't set over the tube, it was simply narrower than a steel ruler.






Many small scrape marks were made down the pencil lines with a #11 blade in an X-Acto handle.
The scraping width has to be narrower than the 3/32" thick scramjet housing sides.

Yellow glue was used to tack the housings in place.
This was followed up with Titebond M&TG fillets.

Look inside the housing and you can see where the fillet stops. I couldn't find an easy way to get the glue farther inside.

There are some sanding marks in the fillet areas. These will get some gloss white applied with a Q-tip before the final spray coats go on.

Estes Orbital Transport, Kit #K-42, Part 17, More Fins & Pre-Paint

I used the old kit marking template for the wing fin positions.
Pencil marks were made in three different locations by sliding the template down the main tube.

There's not much filler/primer after sanding.
Some 400 grit was wrapped around a Q-tip for cushioned sanding down the pencil line.

The smaller wing fences and and larger rudders are glued on.
I used my small machine square again to make sure they were perpendicular to the wing surface.

I still haven't glued on the scramjet assemblies yet. I wanted to hit it with a light coat of gloss white before gluing to the underside of the wings. There are many inside surfaces that would be hard to get a good coat of paint.

The glider is ready to be painted.
The nose cone was left off so I could slide a painting dowel in the front end of the glider.
The nose cone shoulder was masked off and painted separately.

Estes Orbital Transport, Kit #K-42, Part 16, Small Fin Placement

Here's a view from the top showing the glider support piece positions. The instructions say to glue them 2 7/8" from the rear. I glued them 3" from the rear so they didn't overhang the glider wing.

The ventral fins on the bottom.

It's a little tough getting the fillet on next to the rear launch lug.

I used a wrap of tape to place the forward tips of the canard fins evenly.  These canard fins were cut from 1/16" balsa.

Pay attention - Throughout the build you are going back and forth between 3/32" and 1/16" thick balsa.

Estes Orbital Transport, Kit #K-42, Part 15, Ventral Fins & Glider Support

Mentioned earlier, my eight fin evenly spaced marking guide doesn't work for the ventral and glider support fins.

On the left you can see how those marks line up with the original kit marking guide. Good thing I double checked before gluing!

I use very little glue to place fins on a body tube.
Above is the initial glue bead, below is how much glue is left after wiping off the excess. Less glue will actually tack the fin on quicker. You can always add glue fillets afterwards.

I ended up moving the glider support pieces more towards the upper center. This is shown two pictures below.

After the (barely glued) fin was removed I lightly sanded the tube smooth.
Instead of spraying the entire model, I sprayed some filler/primer in a baggy stuffed into a small plastic cup.

A Q-tip was dipped into the filler/primer and rolled over the rough area.
After it dried it was sanded with 400 grit.

Here's why the pieces were moved a bit closer to the center. In the top picture the glider bottom doesn't even touch the support pieces. The glider would flop around in the wind.

Here's the glider fit after moving the support pieces closer together. I have to wonder if the support pieces were always a bit off.

From the side, there is almost an even spacing between the booster and glider bottom. Much better!

Estes Orbital Transport, Kit #K-42, Part 14, Glider Assembly

The wing is glued onto the glider BT-20 tube.

TIP: Don't even try to make a glue fillet in the tight wing joint. It would take too many bubbled glue fills adding weight to the glider.
I did add a fillet to the front and rear of the wing - not down the sides.

The glue side of the elevon was also sanded at an angle for a better joint. This make for a better fit and a stronger model.








The original kit guide was used to set the elevon angle.

The glider nozzle was made a double layer nesting "super shroud" for strength.
Here I'm cutting off the overlap of the inside shroud.

Here's the thicker nozzle glued onto the laminated rear disk.

Estes Orbital Transport, Kit #K-42, Part 13, Glider Wing Fit & Fill

Notice the break at the butt joint of the two wing sides.

Using a sanding block, a slight angle was sanded into both wing root edges.

The sanded angle makes a better fit and a tighter glue joint.

Glue is applied to one side of the wing. I don't use much glue so I can make adjustments if needed. Both sides are joined. The dihedral is made automatically when the wing tips hang over and touch the table top.

TIP: Roll a dowel or pen barrel over the seam to even up both sides of the wing joint.

I got a very clean, even joint.

Now a fillet can be applied to the opposite side.






Notice the tape down the center joint of the wing. This keeps the paint out of the inside gluing angle.

To keep things light, I didn't spray filler/primer. I'll go right to light coats of gloss white with sanding between coats.








This is the inside surface of the wing. The tape strip has been removed to glue the wing to the BT-20 tube.

Estes Orbital Transport, Kit #K-42, Part 12, Wing Filling & Gluing

There's a LOT of balsa pieces!
Everything was filled with sanded CWF and sanded primer/filler.

Both sides of the wing were glued on using my Odd'l Rockets Fin Tool. These fins are far forward so I visualized the position through the slots in the base of the tool.

The wing tips are glued onto the outside edges of the wing sides. I should have done this before using CWF and filler/primer on the wings!

On the left you can see where the gluing surface was scraped for a better bond.

The edge is sanded round.

I had to go back and fill the end grain and joint seams.