Thursday, July 3, 2025

Aerotech Mega Initiator #89541, Part 20, Installing The Rail Buttons


Mix up a small amount of epoxy.

I wanted some of the epoxy to be on the inside of the body tube, directly around the screw - sort of an interior fillet.

A toothpick was dipped into the epoxy and set into the drilled hole. With an in and out motion, a ring of epoxy was left on the inside and outside. 




Slide the rail button onto the screw.
Dip the tip of the screw in the left over epoxy.



Screw the rail button into place. Tighten until the back of the button is flat against the body tube. 

Don't overtighten, you don't want to strip what threads you are making in the body tube.


In the above picture,
Notice the squeeze out of the epoxy.

Wipe off the excess. Depending on the drying time of your epoxy, it might run! I use 30 minute epoxy and a drip could form.

Wednesday, July 2, 2025

Aerotech Mega Initiator #89541, Part 19, Drilling The Rail Buttons

The rail buttons are centered between two fins, on the other side of the INITIATOR name sticker.


It's difficult to find the center on a round tube.
I used a piece of paper pressed into the root edge fillets.

Mark the two fold sides with pencil.
With your ruler, find the center and mark.
    
The lower hole is to be placed about 1/2" above the lower engine mount centering ring. That puts the hole position at about 1 1/2" from the rear of the body tube.

The upper hole is 8" above that.

Drill a pilot hole using a 1/16" drill bit.
Sight from the rear and make adjustments using the larger 1/8" drill.




Using the pilot hole as a guide,
Enlarge the rail button hole to 1/8".

Tuesday, July 1, 2025

Aerotech Mega Initiator #89541, Part 18, Setting The Name Sticker


From the last Mega Initiator post - 

With the O and R "cut" directly over the tube joint, sight down the body to make sure the orange line and type are straight. Tape down the sticker.  

Use your aluminum angle to check the orange stripe is straight.
The placement illustration says to overlap by 1/8", but I wanted to end up with a clean cut between the O and the R.
A 1/4" overlap puts the cut between the letters.

Double check the 1/4" overlay of the orange stripe joint before peeling off the backing.
I peeled the backing on the orange strip and lightly held the  vinyl. The backing was cut off up to the R. 

The orange stripe was set over the upper stripe matching the edges.
With the ends matched up, the backing is pulled under the name. Carefully set down the name checking the straightness as you go.
Add the "C" tail sticker at the low end of the orange stripe.

GOTCHA: The illustration drawing shows the "I" even with the top of the fins. The provided sticker lengths end up with the name higher up on the model.

Monday, June 30, 2025

Estes AMRAAM AIM-120 Downscale, Build, Part 14, Finished



There are PLENTY of small decals on the model.

It's confusing trying to apply them using the Estes instructions. I did my best, some placements are a good guess. 

Online pictures of the real missile don't show the AMRAAM name. It might be Estes took some liberties like they did with the old Honest John kit. The name Honest John never appeared on the actual missile.




Here's the upper end. 
I hope it's stable! There's 1/2 oz. of nose weight in the nose cone.



And the Back end - 

No tail cone, it's a semi-scale build at best.

Sunday, June 29, 2025

Estes AMRAAM AIM-120 Downscale, Build, Part 13, Decals


Applying a light color home print decal over gray paint will end up a much darker color.
You'll need a white underlay.
Black decals don't need any white underneath.



You can either:
Use a white decal strip under the light colored decal or - 
Spray gloss white onto a clear decal sheet.



TIP: Cut a strip of the white sheet, the same width of the colored band.

Lay the white underlay strip down first as a regular water slide decal and let dry.

Apply the yellow strip decal directly over and on top of the white band. 
I didn't find it necessary to use the white strip under the brown decals. They were darker and didn't show much difference over the light gray paint. 

Set the strips down a little long, and trim against the root edge of the conduit with a single edge razor blade.

Saturday, June 28, 2025

Estes AMRAAM AIM-120 Downscale, Build, Part 12, Shock Cord & Parachute

The elastic shock cord was tied to the lug at the bottom of the nose cone shoulder. Notice the tail was not cut off.

When packing the chute, the short shock cord tail can get wedged between the nose cone shoulder and the end of the body tube.

TIP: On this style nose cone - Push the shock cord tail inside the open holes beneath the tie off lug.




The parachute shroud lines were tied to a shock cord loop a few inches away from the nose cone. 


I used the Target bag parachute shown in an earlier blog post.

Friday, June 27, 2025

Estes AMRAAM AIM-120 Downscale, Build, Part 11, Gray Paint & Decal Print





Here's the lower half, painted with Ace Hardware Light Gray.


The upper half, also in Light Gray.

There are still some glue boogers that need to be sanded.
Another final light gray coat will follow.

The nose cone is painted white.
I drew up decals for the downscale BT-50 size.

The decal sheet is only available to Patreon supporters.
Email me at oddlrockets@bellsouth.net and ask for the AMRAAM decals.
The home print PDF also includes fin patterns and a parts list.

The picture shows an early version of the decal sheet. I've made changes so the decal positions match the Estes sheet.

Thursday, June 26, 2025

Estes AMRAAM AIM-120 Downscale, Build, Part 10, Fillets & White Undercoats

I know, I'm bouncing between builds! I'm sure you have two or three rockets in progress at one time.




Even though I had a fairly tight fit, there were still bubbles in the conduit glue fillets!






There isn't much space between the fins and conduit for a glue fillet.

I applied a line of wood glue to a Q-tip and spread the fillet drop by drop. 



White undercoats have been sprayed.

After the paint dried, those fillets between the fins and conduits weren't that smooth. The rough areas required some sanding with 400 grit before additional white coats.

Wednesday, June 25, 2025

Aerotech Mega Initiator #89541, Part 17, Setting The Name Sticker



Take it from an old typesetter - 
"Os" are typically taller and extend beyond the baselines of the other letters.
Be careful when trimming close so you don't cut off the top and bottom of the O.

You have to decide if the vertical orange line or the name INITIATOR will be centered between two fins.

The INITIATOR name is bolder so I decided to center that vertically.

Don't peel the backing off yet. With tape on the back to hold it onto the tube, measure and center the name. 
I am holding the name low, between the fins to find the center.


Rotate the to upper tube to line up the lower vertical orange line with the upper line trailing down. I used my aluminum angle to position the lines.







When both the orange ends are joined and touching, tape the body tube to keep everything in line.








With the vertical orange line overlapping about 1/4" at the top, it puts the break line between the O and the R.

Wait until the next post before peeling off the backing.

Tuesday, June 24, 2025

Aerotech Mega Initiator #89541, Part 16, Pulling The Mask - Sucess!



The nose cone was slipped in and the upper end was sprayed with Rusto 2X Apple red. 

I would normally prefer using Ace Hardware Premium Enamel, but their "Banner Red" is darker and I wanted to get close to the red color on the model stickers. In the end, if the top roll sticker and bottom fin red colors are a close match. You can't tell a difference with the visual distance between them.


After about 30 minutes the paint dried quick enough to pull the masks.

The color mask lines were clean and sharp.


I had a small bit of red that got under the tape.

This was easily scraped off the clear area using a knife blade.

Monday, June 23, 2025

Aerotech Mega Initiator #89541, Part 15, Matching The Nose Cone Color

The question has come up on the forums: 
"Which Red spray paint color will match the red sticker on the Initiator? 

Some considerations:
1. The nose cone is molded in black plastic so it would require a good white undercoat. Otherwise, you'll get a darker red on the sprayed nose cone.
2. The Aerotech printed stickers are translucent. The white paint under the sticker makes the red in the sticker almost a brighter red "candy" color. 

I've been to a few hardware stores with my kit stickers in hand, trying to match with any red spray paint available. Sure, they look close side by side, but on the model it's a different story.

Model building is a little like a puzzle. Sometimes I ponder assembly questions awhile until I can come up with a good solution. This one took longer than expected.
I decided to mask and spray the red on the wrap and nose cone at the same time. This will require masking the area at the top of the upper wrap.



Before spraying the model, I tested to see if the paint might bubble up on a scrap piece of leftover sticker material.

No bubbles and a good adhesion.
I marked a thin strip of Scotch tape with a Sharpie. After marking the tape, wipe off any excess ink with a paper towel.

I had to use a thin strip so I could flex the tape around the curve without raised folds.

On the right is the full border mask. The rest of the area underneath must be masked off.
Widen the mask below with a single strip of brown masking tape. Note there are many fold bulges. The upper edge covers about half of the Scotch tape mask.

On the right side is the full mask. The nose cone will be slid in and both will be shot with the same red color.

I know - Why not just use Tamiya tape? 
I'm cheap and I get just as good a result using inexpensive Scotch tape.

Sunday, June 22, 2025

Aerotech Mega Initiator #89541, Part 14, Applying The Upper Roll Stickers

A great thing about this design, the separate upper section allows you to center the vertical name and red stripes after the large roll sticker is in place. Simply rotate the upper section and center the remaining vertical name stickers between two fins.




To start, don't peel off the entire backing,
Peel back an inch and fold back the backing paper.

This gives you control as you line up the left edge onto the faint pencil line you drew with the aluminum angle.





With the top and left side edges lined up - 
peel back the backing paper as you go.

Smooth the sticker removing any bubbles.
Peel back more of the backing paper and smooth again.

Continue around the tube to the starting point.





With any luck, you'll get a good match of the orange and red prints.

I had to carefully lift the sticker edges to erase the pencil line which showed up under the clear areas. Whew!

Mentioned earlier - these stickers go on without using water as a lubricant. They did go on easier than I thought they would.

Saturday, June 21, 2025

Aerotech Mega Initiator #89541, Part 13, Prepping More Stickers



Here's the upper body wrap. 
The curves were cut with scissors. Notice I cut a little away from the orange arcs, just playing it safe on the clear border.

Cut the straight lines with a knife and straightedge.
 


In addition to lining up the top edge with the tube end,
you'll need to line up the wrap left side down the tube.

Use your aluminum angle to draw a light pencil line down the tube, as long as the left edge of the wrap.


Before peeling off the backing, do a dry fit.

When the lower arcs were lined up, I noticed one side of the wrap was a bit tall. I went back with a straightedge and cut a long sliver to even up both sides.

Next post we'll attach the roll wrap. It's easier than I thought it would be.

Friday, June 20, 2025

Aerotech Mega Initiator #89541, Part 12, Applying The Stickers

I know - I postponed some posts on this build. There are good reasons why. 
I'm not very experienced making epoxy fillets. Sure I've done them, but I'm not enough to show you a best method. 
Another reason - It's difficult to get an even, gloss paint finish on large rockets using store bought spray cans. If you've ever tried to get a good gloss on a 4" diameter model you know what I mean. You really need a spray gun and maybe an auto body spray booth! 

 I do have experience with stickers, this kit has peel and stick decor. But, there are some concerns. Some kit stickers are now printed at Aero tech and require different considerations. 
In the past I've wet the surface of the model and dipped the sticker in a dish of water. The water allows repositioning. It's rare when a sticker is perfectly positioned on the first try. 
I tried the water dip but it loosened the adhesive on the back of the sticker! Pulling up the sticker to reposition it lifted off the adhesive making the surface lumpy and unacceptable. 
Something different about these stickers - Using no water allowed for some lifting and repositioning! 
They still grab so be careful when initially setting them on the model surface.

You may have an older Aerotech kit, the stickers might work fine when dipped in water. 
TIP: Test using water on some of the blank scrap material between the print images.
   



It helps to dry position the fin stickers.

Don't peel off the backing yet!
Here is a roll of masking tape on the back of a fin panel.
The decal is dry positioned on the fin and the tape pressed to hold it in place.

With the sticker set on the fin - 
Use some small pieces of masking tape to "frame" the sticker centered on the fin.

Lift the sticker panel leaving the tape frame in place.
Peel off the backing and set the sticker on the fin using the masking tape frame to position the sticker.


Smooth out the sticker from the center to the outside edges.

With any luck the other fins should be centered (even white borders) and mirror each other.

Thursday, June 19, 2025

Estes AMRAAM AIM-120 Downscale, Build, Part 9, Launch Lug & Conduit Gluing


It'll be hard to reach the root edges once the wide conduit/tunnel is glued on. There isn't much room for glue fillets.

I decided to lightly smooth the dried glue fillets with 400 grit wrapped around a Q-tip for cushioned sanding. Go easy, it is possible to sand a shallow groove in the balsa. You are just knocking down any roughness.


I applied two fine lines of wood glue so there wouldn't be much squeeze out when pressed in place.. 


The lugs were set down and positioned using long tweezers.




I won't be applying glue fillets to the launch lugs. Sometimes trying to fill the bubbles of dried glue isn't worth the time.

The narrow glue lines were positioned so there wouldn't be any visible glue when the lugs were pressed in place.

The conduit/tunnel was centered between two fins on the opposite side of the engine hook and launch lugs. The older Estes instructions showed the tunnel on the same side of the engine hook. I thought it would be more interesting in launch photos with the tunnel facing out.

Wednesday, June 18, 2025

Estes AMRAAM AIM-120 Downscale, Build, Part 8, Gluing On The Eight Fins





The lower fins are glued on with the trailing edges even with the end of the body tube.


Standard, 90 degree spacing with the engine hook centered between two fins. 

Sight across the bottom to be sure the opposing fins are in line.



The upper fins are 8.20" from the bottom of the model.




A wrap of masking tape was rolled around the tube to line up the trailing edge corners.

Be careful not to glue the masking tape to the fins or body tube.