Estes Skytracer Clone #1361 Build, Part 2, Engine Mount

The original kit did not have an engine block. I added the engine block.

TIP: Instead of just cutting a slit 1/4" from the top (as shown in the instructions) I set the engine block beside the tube and mark the top edge with a sharp pencil. This puts the upper bend of the engine hook right above the bottom of the engine block. Quest kits are marked and slotted this way.

The centering rings were way too tight around the BT-20J engine tube. 400 grit sandpaper was wrapped around a finger and the inside burr was sanded down.

On the right, a notch was cut in the upper ring for the Kevlar and engine hook fit.

Here's a dry fit of the rings and engine hook. Kit  instructions typically have the upper ring even with the top of the engine tube.

TIP:  For a stronger mount - Position the upper centering ring down over the top bend of the engine hook.

TIP: Sand the face of the low centering ring flat before gluing onto the tube. That low face of the ring will be exposed on the finished model, when even with the end of the BT-50 main airframe tube. You'll want that flat surface smooth.

 

Fillets are applied to both sides of the rings leaving the Kevlar slot open.

Tie the Kevlar line around the tube. I lace the end under and over the loop a few times. You could use a knot but there isn't much room between the BT-20 engine mount and BT-50 body tube.

 

Cut off the excess and press the end into the wet glue fillet.

Mentioned earlier, a engine block was glued into the top of the mount even with the top of the tube.

Estes Skytracer Clone #1361 Build, Part 1, Parts

All the parts:

You can see where I've penciled in the lengths of the pieces. 

Many dimensions come from the John Brohm list: CLICK HERE

Other lengths come from searching old catalogs.

Parts "K" that make up the nozzles will be fashioned from some spare parts. Cut-up 13mm plastic nose cones, cardstock and engine blocks.

The PNC-50S nose cone will be made from a Crossfire style cone with an added cardstock canopy drawn up by Greg Poehlein: CLICK HERE

Estes Skytracer Clone #1361 Build, Background

I often browse the old catalogs at Ninfinger.org looking for the next interesting build.

This one caught my eye! Here's the page: CLICK HERE

The Skytracer was only sold in 981 through 1982. Sure, it's a bit different, 

but that's what'll make it a fun clone.

Specifications: Length: 13.0", Diameter: 0.976", Weight: 1.9 oz.

Recommended 18 mm Engines: A8-3, B4-4, B6-4, B8-5, C5-3, C6-5

The two central fin nozzles (facing the rear in the photo above) are made by combining the front and rear of the old Centuri Shuttle SST jet engines. 

Centuri also used these nozzles on their Quasar kit. To see my Quasar clone build: CLICK HERE

If memory serves, my Shuttle SST kit originally had vacu-form nozzles. Later on the nozzles were injection molded. Estes found some use for the molds in the Skytracer. I'll be assembling the nozzles with segments cut from plastic nose cones.

The build starts tomorrow . . .

My Spray "Booth"

Here's where I spray my model rockets.

It's simply a walled patio between my townhouse to the right and separate garage to the left.

The block walls are 8' high which (somewhat) provides a wind break. That cardboard on the ground protects my brick pavers from any paint drips that might form on the nozzle. 

I haven't found any overspray paint on the walls, floor or glass on the house walls.

A windbreak is important. I did notice James Duffy's spray booth on his NARCON video. He sprays his models in a horse trailer.

 Why an enclosed horse trailer? No wind!

Clearing A Spray Can Nozzle?

Jmg8torr posts construction and home tips on YouTube.

To see the video: CLICK HERE

I haven't tried this one out, but am curious.

This might help with clogged spray can nozzles. 

I would recommend spraying a few passes away from your rocket to be sure any WD-40 is blown out.

New Way Nike Ajax Build, Part 22, Finished

This is a tall one at 30.75" tall.

A good semi-scale representation.

The tunnels are hard to grain fill, the space is tight with 12 fins and four long tunnels.

I sprayed a dull coat to visually hide some fillets that were rougher than I liked.

The interstage portion with the black band decal simulating a gap between the stages.

The white decals work well if placed over a clear gloss coat. After the decals dry, follow up with a dull coat and the clear areas of the decals should dissapear.

 

The Nike style flat fins, built as shown in the instructions.

Interesting that the two piece fins are glued together at the mid point, the same centerline where a true diamond taper would start.

New Way Nike Ajax Build, Part 21, White Decals

I positioned the white decals on the lower stage tube to get an idea of the spacing.

All the white decal go on one side of the tube, centered over the fin opposite the launch lugs.

After the decals dry, the lower body got a clear dull coat.