Estes Cosmic Interceptor Build, Part 16, Filler/Primer On The Balsa Parts

Here's all the parts taped down to scrap cardboard for a shot of filler/primer.

Notice the thin masking tape strips over the gluing area slots on the Q pieces. There is tape over the glue tabs on the T pieces.

With the S braces dry fitted, this will mask the gluing contact areas.  

After the filler/primer shot,

the glue tabs have no spray.

The wing showing the clear glue areas for the S braces.

The end tip Q pieces had a measured strip of masking tape over the gluing area.

The open CWF strip isn't sealed and glue can be absorbed. The gray filler/primer seals the rest of the balsa.

Estes Cosmic Interceptor Build, Part 15, More Pre-glue Fitting

The low edges of the intake tube will set into the fillet joints of the wings.

Looking ahead, I checked how straight the sides were using an aluminum angle. This will require some sanding to get the sides straight. notice the pencil mark - 

The visible end edges of the intake can be cleaned up with a wipe of CA glue and light sanding. This removes the fuzz and sharpens the looks.

Don't wipe any CA glue where wood glue will follow.


 

I set the vertical brace in place to mask the gluing areas for the filler/primer shoot.

The underside tabs aren't tall enough to fully fill the notch! This will need more filling after gluing the braces in. No glue yet, wait until after sanding the filler/primer.

Estes Cosmic Interceptor Build, Part 14, Tube End Fitting

The main tube and the back of the intake tube will be glued even.

With the intake vanes in place - setting the intake tube to the low end of the main body tube, the edges are uneven.

Set the high end of the intake even with the main tube end. This will end up with a slight overhang of the intake tube sides.

Tape the intake tube sides down for stability when sanding.

Using 220 grit,

Sand the intake overhang even with the main tube end.

A dry fit of the assemblies -

Estes Cosmic Interceptor Build, Part 13, Intake Vanes

Think about what will be seen on the finished rocket.

The intake vanes might float above the main body tube - 

The base of the vanes should contact the body tube. Any gaps at the top of the crescent pieces will be covered by the tapered intake tube.

Glue the intake ribs on one at a time and let them dry one at a time. Make sure all the bottom edges contact the tube.

A dry fit of the intake tube set over the intake assembly.

I'm in the middle of filling the seams on the tapered intake tube.

The raised intake tabs all touch the front of the curved intake tube.

Estes Cosmic Interceptor Build, Part 12, Intake Vanes Fit

Here's the laser cut intake vane cardstock.

The pieces aren't marked, they vary slightly in size and length.

The picture on the right side shows a dry fit. 

The long pieces are too loose when set in into the AA and BB part notches.

 

I like to seal the exposed edges with glue and sanding. It makes a big difference on the finished model.

The area below the pencil line is what will be exposed.

The right side pic shows a round bead of glue after removing the excess. There is only glue on the edge, not on the sides. The glue in the picture is already half dried.

Sanding with 400 grit smooths out any irregularities.

Estes Cosmic Interceptor Build, Part 5, Fitting The Vanes

The engine hook retainer ring is rough with a wide seam that could be seen when painted.

I added a wrap of copy paper with a glue stick. This smooths out the surface and covers the seam spiral.

I sealed the surface with some CA glue wiped on with a Q-tip.

Notice the CA glue is not applied on the line where the vanes will be glued.

On the left is the glue applied to the vane root edge.

On the right is the same glue line after smoothing and removing the excess. This makes a cleaner glue line when the vane is pressed in place.

Set the first four vanes in a standard cruciform pattern.

When setting the other four, you might want to rely on visual spacing instead of strict pencil lines. Even with my payloadbay.com marking guide, I found a visual spacing was closer to the truth.

On the left - Notice the fit of the two vanes that glue beside the engine hook. Over the engine hook, the retainer ring is raised. 

On the right - The center notch was deepened with a diamond file to bring all three contact points onto the tube.

Estes Cosmic Interceptor Build, Part 2, Centering Ring Fitting

Here's all the engine mount parts - 

The centering rings are on the laser cut cardstock sheet to the right side.

This build will involve some fine fitting of parts.

Save the excess cardstock,

at least the large pieces left over.

It'll come in handy for a future build.

The fit of the rings was so tight, they wouldn't slip over the engine tube!

Wrap some 220 around a finger to enlarge the hole until you get a friction fit.

 

Here's the fit I was looking for!

Estes USS Enterprise #1275, Part 29, The Tail Caps

GOTHCA! The tail cap liners (slip-in shoulder base) won't fit into the tail caps!

The diameter of the liner is the same diameter of the tail cap. Notice the sides of the liner taper towards the right side.

The instructions say to "sand the liners until they fit 1/4" into the tail caps. I sanded using 220 grit.

The picture to the right show how much of the edge was sanded off that first shoulder.

 

After sanding, one tail cap liner slid in.

The second liner required a cut slit in the side. No amount of sanding the tapered shoulder would allow a slip fit.

Estes USS Enterprise #1275, Part 19, The Radar Dish

A hole is made in the radar dish center to fit over the sharpened dowel.

Start the hole by spinning a blade tip in the center.

Enlarge the hole using a small rat tail diamond file. By using a file to open it up, you'll end up with a rounder hole.

Careful, it's easy to make the hole too big. File a little and check the fit. 

Glue the dish using liquid plastic cement.

The "ball" at the end of the dowel tip is a drop of white glue. You might have to build up the diameter of the ball using a few applications of glue.

Estes USS Enterprise #1275, Part 17, The Homing Beacon

The homing beacon is cut off the vacu-form sheet the same way the larger pieces were.

Ball point pen outline, then scoring the edge.

Break away the sides by cutting and cracking off angled wedges.

The sides are a little rough after the first cuts.

Sand the bottom flat until the edge starts to roll off.

The finished beacon wasn't perfectly round.

The instructions say to sand down the overlap seam 3/8" wide, 1/8" from the rear. The pencil marks show how wide that marking is - too long.

On the left, the overlap ridge is removed to fit the actual diameter of the beacon.

On the right, the fitted and glued on beacon.

Estes USS Enterprise #1275, Part 16, The Hull Pylon

The internal pylon assembly was set inside one side of the secondary hull. A pencil line was traced around the bulkhead.

Contact cement was applied on one side at the pencil bulkhead line and at the pylon doubler contact areas.

Repeat for the other side.

Before allowing the pieces to touch - carefully align. 

The pylon assembly was pressed in place.

Be sure to check that the slots line up at the back.

The secondary hull assembly.

Two small hairline cracks occurred on the forward end of the hull. The cracks formed where the plastic was the thinnest. 

I'll fix this in a later post.

Estes USS Enterprise #1275, Part 15, The Hull Pylon

The doublers are glued on each side of the hull pylon.

Do your best to center the doublers

 -

 

Here's how they lined up.

I lined up the doublers using the retainer ring recess at the top. That left the front and rear of the doublers short against the center piece.

Rounding the front and rear did clean up the short side pieces.

For a better fit against the motor mount tube, a curve was sanded into the top of the laminate pieces. Otherwise, there would be gaps on both sides when glued up.

The bulkhead piece was very loose around the back notch of the central pylon piece.

A cardstock strip shim was glued on the inside for a tighter fit.

Estes USS Enterprise #1275, Part 14, Secondary Hull Brace Slot Cutting

I put off cutting the brace slots in the secondary hull. I wanted to practice on cutting the tube slots first.

Draw a pencil line a bit smaller than the brace width. Square on the front, round on the back. 

Use the tip of the knife to make the square corners.

Note the blade is turned up to make the lower corner cut first. 

The long sides are cut.

Leave the rounded back end for last.



I used a round diamond file to extend the width and round the back.

Finish up with a flat file for the sides.

Here's a good friction fit of the brace in the slot.

Estes USS Enterprise #1275, Part 13, Pylon Brace Gluing

A quick update after my dog Dakota's first camping trip - 

She did great! Lots of new smells on the hiking trails. Met a few people and slept through the night on her dog bed from home. 

Didn't bark once - until she got home.

    

The instruction drawing shows the interior brace contacting the tube at the 3 and 9 o'clock positions.

My brace position ended up lower inside the tube.

You can see some glue reflection inside.

I used a glue bead on a Q-tip to reach inside and apply fillets.

The corner of a CD case was used to check the right angle of the pylon brace on the tube.

Estes USS Enterprise #1275, Part 12, Gluing The Support Ring

The contact cement capsules have dried out and aren't useable. I bought some new contact cement at Home Depot.

If you've never used contact cement before - 

You apply the glue to both parts and let it dry. When the dried glue touches the other glued part, it grabs and holds strong.

There is a good reason why it is called "contact" cement.

The support ring is centered in the bottom hull half and the perimeter is traced with pencil. Center and trace the ring on the upper and lower hull halves.

A ring of contact cement is brushed on the pencil line.

Contact cement is applied to the edge of the support ring and allowed to dry.

Center the ring inside the pencil line and press into the hull.

Here the lower edge of the support ring is set and glued in place.

Apply contact cement to the upper edge of the support ring and inside the pencil line in the upper half.

Fit, press and join the two hull halves together adhering the support ring in place. 

Held up to a light you can see the ring inside the round hull.

Run liquid plastic cement inside the overlapping joint.

Dip and push the brush into the seam as best as you can.