ASP MMX Micro Corporal Build, Part 2, Fins

The full-size fin templates are printed in the instructions. With a pencil and straightedge I extended the outside lines for an easier cut.
The instructions mention using double sided tape to hold the small strip of plastic fin material. With the extended lines, I could simply tape the plastic strip down on top of the template.

With a straightedge and sharp blade, the plastic strip was scored about halfway through.

You can then flex and crack the plastic down the cut line.

Here's the four fins, cut out and ready to be evened up.

The kit gives you enough plastic for a few extra fins if needed.

The fins are small and evening up a full stack was difficult. Here you can see two fins are a bit longer than the others.

I couldn't stack and sand all four fins at the same time. Each fin was shaped separately. Check the size adjustments after a few swipes with 400 grit on a block.

ASP MMX Micro Corporal Build, Part 1, Parts

In 2014, I built the 18mm Corporal from Aerospace Specialty Products (A.S.P.)
I was very impressed by the fit and finish of the parts, especially the fit of the vinyl cut roll pattern. I understand the vinyl has been replaced with a water slide decal.

I was interested when I saw a Micro Maxx version of the Corporal was available. I understand ASP has more MMX kits on the way!

Here's all the parts! 

No balsa or basswood on these little rockets. The fins and tunnel details are cut from plastic. The body tubes are small diameter Kraft tubing

Parts of interest:
On the left is the fin material. It looks small but there is plenty for the four triangular fins.
To the immediate right is the half round plastic tunnel material.
The nose cone looks to be 3D printed. The nose weight is a split lead shot piece. Below that is the plastic launch lug.
On the far right is the water slide decal sheet.

Estes Doorknob, #9720 Build, Part 14, Sport Version Finished

Well, I do have pictures of this version -
I did my best to match up the blue spray paint with the blue in the decals. It's close!
The Rusto 2X Brilliant Blue is a little bit darker than the decals on the fins.
This model will be a popular rocket for Estes. Big and burly!

Estes Doorknob, #9720 Build, Part 13, Sport Decals

On the left is the "Sport" decal available by mail from Estes.

I found the decal shapes and the positioning to be a bit confusing. The decals were cut to shape while still on the backing sheet. The decals were taped onto the fins to be sure of the positioning.

Be sure there is a straight line down the middle between the two decals.

Notice the back edge of the decal overhanging the trailing edge. Cut the back edge close.

The black strip bands are from the "scale" decal sheet.

I used a wrap of tape for an alignment guide. This helps insure the narrow decal is on straight and will meet up on the other side.




After the decal thoroughly dried, some Future clear was wiped on the rear edge for better adhesion.

NOTE: The sport decals cover facing fins on two sides of the model. There aren't decals for all sides of all fins.

Estes Doorknob, #9720 Build, Part 12, Decal Fix & Finished?

I had a chip in the black band wrap decal.

On the left is the chip,
on the right shows the fix.

TIP: Save old decals sheets!
You never know when you might need a patch. I cut a very small piece from an old Estes S.W.A.T. decal sheet. There is some clear on the sides of the black area so I had a little more surface grab.

I don't have finished pictures of the build!

I took finished pictures - outside, because the model is on the bigger side.

For whatever reason, the pictures weren't saved on the flash card.

The image above is from the Estes website page. Two of the scale builds were sent back to Estes.

I do have pictures of the Sport version in the next blog posts - 

Estes Doorknob, #9720 Build, Part 11, Decals & Chrome Trim

This is the fin rivet and bolt plate decals.
The wider spaced rectangles go to the top. The decal strip is centered down the root edge.

If you are new to water slide decals -
TIP: The picture on the right shows the transfer onto the model. Wet the decal placement position on the model before transferring the decal. Slide a little of the decal off the backing sheet. Set the bottom of the decal onto the model, and continue to slide the backing up and off leaving the decal in place.

Here's the rivet plates on two facing fins.

TIP: Notice the paper wrap at the top. This keeps the model clean while handling. The paper wrap is rolled on and taped in place. Tape the paper wrap to itself, not onto the painted model.

The self-adhesive chrome strips are thin. They are place over the paint mask line. The raised paint edge could show through the thin chrome band.

TIP: Lightly sand the color separation line where the chrome strip will be. The masking paint ridge could show through the chrome band. I've wrapped some 400 grit around a Q-tip for cushioned sanding. Don't over sand, just knock down the raised paint edge.

The placement of the chrome strips shown in the instructions was confusing. I understand it is being corrected.

I wrapped a copy paper strip around the body tube for a straight line reference. You'd be lucky if the sticky wrap would end up in a straight line  without a guide.

On the right, keep your fingers off the sticky back side of the thin bands. Dirt and fingerprints could show through.

Here's the finished wraps.
Chrome always adds a lot to the finished look.

Die Cutting Fins?

Vince Perlman asked on the Facebook Estes Model Rocket page:
Back in the day (until the 80’s, at least) most of your better rocket and plane kits advertised balsa parts that were “die cut”. Sometimes the parts were cleanly cut, oftentimes - not so much. Either way, it was a huge time saver when a lot of parts had to be cut out. I could never picture what balsa-cutting dies looked like or how they were made. I’ve searched YouTube to no avail. Anyone around have any insight on how balsa die cutting was done?

My Answer:

Custom cut and bent razor blades were locked into a wooden block. The black pieces on the outside were soft rubber that would compress when pressure was applied allowing the blades to be exposed. They were good for quite a few clean cuts, then the blades would dull and "die-crush". 
I only have print shop experience when die cutting was done on thick card stock using a Heidelberg printing press. Thin balsa could probably be cut on one of these multi-purpose presses. Thicker balsa might require some sort of clamping press.