Estes EAC Firecat #0821, Build, After Thoughts, A Fix & Comparison

Naoto Kimura wrote in a comment:

"A potential "gotcha" with regards to the launch lug -- the launch lug needs to be offset from the side of the main body tube to make sure the launch rod clears the nosecone (something that the instructions does not state explicitly)."

You know me - I follow the directions!

I should have taken the bulbous nose cone diameter and launch rod clearance into consideration. 

Bar Geezer followed: 

"I glued mine inside the pod on the other side of the pylon. Gives enough clearance for the nose cone and hides the lug."

I ended up doing the same thing! Placed inside the pod the launch lug isn't seen.

I set a line of glue down a 1/8" diameter launch lug. Tweezers were used to place the lug inside the pod. 

Out of curiosity -

I placed the nose cone from the Estes Mini John kit next to the my new BMS balsa Firecat nose cone. The profile is almost the same except for the indented nozzles and lines. 
 

Firecat - Goonycat!

From the Estes Model Rockets Facebook page: 

Stan Lee McKiernan posted:

“With all the Firecats being built with the Mini-Hojo,  

I thought my Gooniecat would only be appropriate to add.”

Great! Now I feel the need to build a GoonyCat!

Estes EAC Firecat #0821, Build, Finished

This could be one of my favorite designs. 

The Estes Aerospace Club got a second (and final) exclusive kit, available only to EAC members.

A great kit bash and helped Estes reduce some inventory. One of the better SPEVs.

The back end from the top,

and the bottom red side.

From one side -

It's hard to make out the small decal positions from the online instruction drawings.

Take your best guesses, there is no wrong here.

That long half-half nose cone mask is hard to get straight. 

Setting the U. S. AIRFORCE  centered on the mask line is brilliant!

This could be part of the Estes Designer Series kits. It's a beautiful design with a great back story.

Add this design to my favorite builds - 

The Dr. Zooch Saturn V, Quest FLV, Sirius 18mm Interrogator and ASP 18mm Corporal.

Estes EAC Firecat #0821, Part 12 - What, Follow The Instructions? GOTCHA!

A Blog Comment from Naoto Kimura:

Naoto KimuraApril 11, 2022 at 4:06 PM

"A potential "gotcha" with regards to the launch lug -- the launch lug needs to be offset from the side of the main body tube to make sure the launch rod clears the nosecone (something that the instructions does not state explicitly)." 

From the Estes instructions: Here's their drawing showing placement of the Launch Lug.

The lug is glued into the root edge of the standoff, closest to the BT-50 tube.

Out of habit and I usually follow the instructions - 

I glued the Launch Lug into the root edge joint.

(Maybe I should have had the Nose Cone in place when the Launch Lug was glued on!)

It probably won't clear diameter the bulbous Nose Cone.

Thanks Naoto! I usually catch these things - Not this time!

Estes EAC Firecat #0821, Build, Part 11, Final Decals & Loose Ends

You've got to cut up the Bandit decals to get the Firecat to look like the face card.

These are the remaining four vertical black rectangles, cut in half. 

Place these on the white side of the body, directly over the rectangles on the BT-48 roll wrap.

The remaining horizontal bars (seen in the first picture above) are cut in half and set behind the U.S. AIRFORCE decals. Because they are short, they won't reach all the way around.

Here's the view from the bottom.

My balsa nose cone was ordered from BMS, #BMS50HJ.

There was a hole in the bottom center, no drilled dowel was supplied or would fit in the small hole.

I was concerned the screw eye wouldn't "grab" well in the center.  

Simple solution - Set the screw eye to the side. Turn it so it won't hit the inside body tube wall.

FIX:

I didn't get good paint coverage on the trailing edge of the vertical fins.

I used a red Sharpie to fill in the red. NOTE: This doesn't always work! Try a small area first. It can fill well on narrow areas like the flat trailing edges of  a fin. It will not work on flat, larger areas.

I forget to paint the toothpick antenna.

It was taped to a dowel, hit with a gloss white coat.

Smooth sanded after drying and sprayed again.

Estes EAC Firecat #0821, Build, Part 10, Layered Decals

The intake/jet tube gets a black and white rolled decal.

At the bottom of the decal sheet are two rectangles, one is an extra.

Cut off the bottom third of the sheet, spray it gloss white. You are making a white, waterslide decal.

The inset picture shows that the box outline is still visible after spraying the white.

This shows my first decal draw, the same width used in the original Bandit kit, to fit a BT-55 tube. The lower intake tube is now a BT-48 diameter.

From the original wrap size Bandit decal sheet  - 

Cut the left side as the picture shows,

The right vertical rectangle cut is four from the end.  

My re-drawn decal sheet doesn't require any fancy cutting. All the decals are drawn to the correct size.

Cut the white decal just inside the black border line. Soak and transfer the wrap.

TIP: Place the "EXPIRIMENTAL" decal first. One goes on either side. Then place the white wrap.

I set the white wrap too far back which didn't leave enough space for the EXPIRIMENTAL decal.

Wait for the white decal to dry before adding the black overlay.

The black ink isn't totally opaque, you can see some of the white underneath. Oh well, it's a clone.

Set the U. S. AIR FORCE decals centered down the color mask. 

Be sure the nose cone/body tube joint is between two letters.

Let the decal totally dry before cutting through the decal at the joint.

Estes EAC Firecat #0821, Build, Part 9, Masking For The Red Paint

Here's the mask covering all the white areas.

I don't recall any other rocket design where the main mask runs and divides the body in half. The smaller wing tips also stay white.

White on the top, red on the bottom.

Use gloss paint for better transfer of the decals. The instructions say to use flat paints.

Here's the mask after the tape was pulled.

For the most part the lines were clean and sharp.

The nose cone mask is tricky. 

I thought it would be easier to match the tape lines after the body was painted.

Slide the nose cone in and extend the body lines down to the center tip. Look down from base to tip at an angle to be sure the tape line is straight. It'll take a few tries, it isn't easy!

On the left is the complete mask, covering the white.

On the right is the red area - half and half.

Here's where we are - 

Decals next!

Estes EAC Firecat #0821, Build, Part 8, Launch Lug & Decals

GOTCHA: Scroll ahead to Build Step 12 before gluing the Launch Lug in the wrong place! The Lug placement needs to be positioned so the launch rod can clear the outside diameter of the nose cone!

Did you ever forget to glue on a launch lug? Me neither! (Yeah, right.) I didn't notice the launch lug was missing until after the first white undercoats.

I had to carefully scrape off some paint before gluing on the 1.25" long launch lug.

TIP: I don't usually apply glue fillets on launch lugs that are tucked into tight corners like this. The glue is very hard to evenly apply and smooth the fillet.

I have drawn up a PDF of the parts list, decals and fin templates. On the right is the first version. The new drawing (see below) is available to Patreon supporters.

If you are a Patreon member, email me at: oddrockets@bellsouth.net and ask for the Firecat decal PDF.

EDIT: After painting the model and applying my decals, I made some changes in the decal sheet, shown on the right.

The original Firecat kit used the Estes Bandit decal sheet. The Firecat instructions say "The name Bandit . . . will not be used."

There's a problem.

To place the decals like the face card and instruction drawing requires things be cut up. Cutting up home print decals exposes the ink edges which can bleed when soaked.

That BT-48 wrap was meant to roll around the Bandit's BT-55 tube. Some test wraps gave me a width of about 10 of the interior vertical rectangles.

Other trim pieces were cut from that remaining wrap decal.

In my re-draw I separated those pieces for easier cutting and transfer.

At the bottom of the sheet are two rectangles, one is an extra.

Print the decal, cut off the bottom third of the sheet. The upper two thirds is clear coated as normal for home print decals. The bottom third is sprayed gloss white.

More on the decal application comes later in the build.

The fin templates and parts list are still included, but on a separate sheet of the PDF set.

Estes EAC Firecat #0821, Build, Part 7, Sub-Assemblies

The BT-48 tube had it's seams filled - the seams you'll see anyway. 

The front and rear of the end joint and spiral seams were filled.

The area in the center will be glued onto the balsa standoff covering most of the seam.

The raceway was painted with some CWF. While it was still wet - The Antenna was slipped into the drilled hole, turned to round out the hole then removed so the CWF could dry.

The instructions don't mention rounding any of the fin edges, but the drawings show them rounded.

After doing some dry fits I realized rounded leading edges would leave gaps at the front corners. (See inset picture) I decided to leave them square.

Here's the wings, raceway and intake/engine glued in place.

Notice the back "step" placement of the small wing tip. A very creative kitbash.

Estes EAC Firecat #0821, Build, Part 6, The Raceway Antenna Slot

The toothpick Antenna is optional. Before drilling a hole, consider this: 

The balsa is 3/32" thick and the hole is tricky to drill. It's something an ejected parachute could get caught on. Decide if you want to tackle the detail.

Use the Raceway pattern to get an idea of the antenna angle. 

Set the template next to the balsa raceway and pencil mark where the antenna hole will be.

I used a small rat tail file to get the hole started.

The file was spun, the angle checked.

The hole was widened using the tapered end of a (un-sanded) rough toothpick. Spin the toothpick, then use the file.

It's easy to crack or swell out the sides of the soft balsa raceway. Go slow - 

The toothpick is smoothed out.

The end that will be glued into the raceway is also smoothed and tapered a bit so sides of the raceway won't bulge out.

Here's the antenna in place. The angle match is good.

Look close at the side of the antenna wall. The side collapsed a bit and that dip will be filled.

I'm not going to glue the antenna into the hole. The antenna will be slid into place for display and removed for flight. 

TIP: This is like the antenna spike on the Mercury Redstone tower. The old Centuri instructions recommend not gluing it in place. Press in place for display and remove for flight.

Estes EAC Firecat #0821, Build, Part 5, Cutting Out The Fins

The fins are cut out from 3/32" balsa.

Notice the line down from the leading edge through the left of the center area. This cut line only applies to two of the four fins.

Cut out four fins, one tube standoff,

and one long raceway. 

As mentioned - 

Only two of the fins have the wing tip cut off.

Here I slid the full fin pattern back to lightly notch the cut line.

Slide the pattern forward and notch the rear of the fin.

Use a straightedge set on the knife mark notches 

and cut off the wing tip.

Estes EAC Firecat #0821, Build, Part 4, Engine Mount

The instructions show the 20/50 rings are glued even with the ends of the engine mount tube.

I prefer to have the upper ring a little lower, overlapping the upper bend of the engine hook. It's a stronger mount when the hook can't tear through the engine mount tube at ejection.

I used one of my Odd'l Rockets heavy wall BT-20H tubes for the engine mount.

To get the 20/50 ring to fit over the slightly larger outside diameter, the inside of the two rings is peeled. It's an easy adjustment, just don't peel off too much.

The picture on the right shows the ring overlapping the top of the engine hook. The penciled box shows where the hook is underneath. 

The upper ring is slid off and a notch cut for the Kevlar shock cord line.

On the left - the Kevlar line is tied off. The line is passed through the notch in the ring. Glue the ring in place.

The lower ring has a 1/8" segment cut out of it to allow movement of the engine hook.

I glued the lower ring on about 1/8" up from the low end of the tube, not even with the end as the instructions showed.

TIP: Slide the ring into your BT-50 tube to hold the ends down while the glue dries.

Estes EAC Firecat #0821, Build, Part 3, Closing The BT-48 Tube Joint

You'll need an interior patch to hold the butted joint seam on the BT-48 tube.

Cut a piece of cardstock about 1/2" wide and 1/4" longer than your body tube.

Pre-curve the piece in your palm using a rolling dowel until you get an arc as shown in the inset picture.

I used a thin coat of wood glue spread evenly over the entire piece.

Press in place centered over the joint. Use the dowel to apply pressure over the patch piece.

After it dries, sand the overhang off using a sanding block until the patch is even with the ends of the body tube.

When you are stuck without a proper part - 

Using this method, you can make couplers to join segments of body tubes.

To smooth out the joint,

Apply a small line of glue the last 3/8" on both sides. 

Wipe off the excess with a fingertip then immediately burnish and roll over the seam with a smooth pen barrel. Pressing the loose fibers into the glue should smooth out the cut. 

The ends will be exposed on the finished model.

Estes EAC Firecat #0821, Build, Part 2, Fitting The BT-48 Tube

You could simply use a standard BT-50 or a yellow spacer tube for the low intake/motor tube and nobody would notice the difference. But what fun it that? 

Tube cutting experience should be part of your rocketry skill set. The diameter of the 2 1/2" long BT-50 tube will have to be smaller to slide into a standard BT-50, like a coupler.

 

Use your aluminum angle to draw a straight pencil line down the length of the tube.

You can use the angle as a guide to cut the first line.

Slide the slit tube into the longer BT-50 and note the overlap. The overlap will have to be cut off.

Slide the slit tube halfway into the main BT-50 tube.

Trace down the overlap halfway down. Flip over the tube and trace the other side.

You might end up with angled lines. It's difficult to get a straight line because the tube shifts.

I prefer to cut the second line with scissors. It's better to cut inside the pencil line a little wide at first.

I used my sanding block to clean up the line to fit into the BT-50.

Here's a good fit of the new "BT-48" tube slide into the main BT-50H. 

The segment joint is clean and the slit tube slides easily into the BT-50H.