Estes Monarch Build, #7214, Part 5, Cutting Out The Fins

There is enough "free" balsa on one side of the Monarch fin sheet to cut out one of the larger, lower Optima fins. 

The other two larger fins will be cut from two glued together  Monarch fin pieces.

Before gluing together the fin pieces, sand the laser cut burnt edges square with a block. Glue the two pieces flat with weight on top.

 

The third fin only needed a small fin tip extension glued on the trailing edge.

From the remaining balsa the smaller forward fins are cut.

All the fins are cut and gang sanded.

Estes Monarch Build, #7214, Part 4, Fins

 

I decided to kitbash the Monarch into a downscale Optima.

I've always liked the dual fin design and bold graphics.

I couldn't find a fin pattern so I looked up a rocksim drawing on rocketreviews.com.

This was copied and dropped into Corel draw.

To do the quick downscale, a circle was drawn to 1.325", the diameter of the Monarchs BT-55 tube. The drawing was reduced to match the tube diameters. This also reduced the size of the fin templates.

A print was made and the patterns cut out.

Now . . . how to cut new fins using the existing kit laser cut balsa sheet.

Estes Monarch Build, #7214, Part 3, Engine Mount

The finger tab was cut off and the engine hook flipped over.

A subtle curve was bent down the length of the hook for better motor retention.

The upper centering ring got a small punch for the added Kevlar line.

The upper ring was slid on just over the upper bend of the hook for strength. 

The rest of the mount was assembled as shown in the instructions.

A 1/16" diameter heat shrink tube was slid down the Kevlar line and against the top of the upper centering ring.

Thanks go to Rick Randoll of NewWay Space Models for this Kevlar heat protection idea. 

A heat gun on low setting shrinks the tube around the Kevlar line.

The inset picture shows the Kevlar line below the base of the lower ring, set into the glue fillet.

Estes Monarch Build, #7214, Part 2, Questions?

It looks like I already sanded the coupler. 

Sometimes these red couplers are too tight and can get locked up in the wrong position when gluing.

Why are two joined tubes used in this design? Was it a SPEV?

The parts list says it's balsa, but a blow molded nose cone is included. No screw eye is provided, it's not needed.

The instructions don't mention using glue on the screw eye threads.

The plastic nose cone has one of the small, breakable eyelets for shock cord and parachute attachment. I'll fix that in a later post.

GOTCHA - In order for the rocket to sit flat on the fin tips, 

The fin sanding instructions are wrong!

The leading edge (shown here) is actually the root edge.

The root edge is the leading edge.

I'm not going to use the Monarch fins. 

The next post will show something more interesting.

Estes Monarch Build, #7214, Part 1, Background & Parts

I'm taking a break on the Enterprise build. I remember pausing the Klingon build a few years back. Sometimes you just have to ease up and build something simpler.

A few years back, I picked up some Monarch kits in an Estes clearance sale. 

We all have kits that sit in opened bags, pieces being cannibalized in other builds. 

That might explain some parts questions.

 

Here's the Monarch, it reminds me of a three fin Big Bertha.

It also looks like the Quest Big Betty with a sleeker nose cone.

BT-55 based, 18mm engine mount. 

There was no parachute in the kit bag, I probably used it in another build. I have plenty extras.

The balsa is tight and stiff.

Estes USS Enterprise #1275, Part 30, Intercooler Dowels

Four short 7/32" lengths of the remaining 1/12" diameter are cut. I usually cut a few extras and pick the best ones for the build.

I like to keep small pieces in zip lock bags until needed.

The dowels were held using tweezers. A line of glue was applied. 

The dowels are placed using the tweezers.

The low end of the dowels butt up against the front of the intercoolers.

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.