Estes Mini Bomarc Clone, Kit #TK-5, Ink Lines Added

I printed up some decals for the Skylab. I only used 3/4 of the sheet leaving me some open area. The Mini Bomarc "ink line" decals were added to the Skylab decal page.

Being narrow, these were a little tricky to apply and keep straight.

The detail lines do add to the finished look.

I didn't roll the ends over the rounded leading and trailing edges. There's a very slight gap.

Estes Pro Series II Mega Red Max

Estes has released a 29mm three engine cluster model, the new 4" Mega Red Max. Checking the instructions: CLICK HERE 

It looks like it has laminated fins you'll actually have to cut out! Oh, the 1960s horrors!

To the younger (laser cut) builders: "It'll build character." You'll end up with thicker, stronger fins than the previous 3" diameter Big Red Max.

The "decals" are vinyl this time around.

I'm glad to see the fin decals are parallel with the table top like the original BT-60 Citation kit. On some recent versions the fin decals were set at an angle, parallel with the leading edge of the fins.

Centuri Skylab Build, #KB-4, Part 4, D.I.Y. Centering Rings

TIP: One of the best centering ring materials is the left over mat board found at a frame shop. Ask the manager if they have any scraps, leftover pieces too small to be used in a frame.

If you're lucky they might give them to you for free! If not free, cheap anyway.

Trace around the diameter of the tubes. Trace the larger tube first, it's easier to center the smaller tube afterwards. 

It might take a few tries to get the smaller pencil ring centered.

With a new blade, cut the center out first. 

Cutting the center hole first is easier when you have more of the cardstock to hold onto.

That small circle in the center was on the mat board from an earlier build. I should have erased it for the picture.

Some 320 grit was rolled around my finger to enlarge the diameter..

Sand a bit, check the fit - repeat until you get a good friction fit.

When the hole is to size,

you might find a raised lip around the edge.

Leave the lip. It gives you a tighter fit and a wider gluing edge later on.

Centuri Skylab Build, #KB-4, Part 3, Making A Centering Tube

From the original instructions:

There is a side Kraft centering tube set over the engine tube and engine hook.

I don't have a 3/4" long centering tube, so we'll "make" one.

Three 20/50 centering rings will be used, stacked and glued end to end.

For tighter glue joints, sand the ends flat.

Slide the rings over a BT-20 tube and glue just the rings together, don't glue them to the tube yet. 

Sliding the rings over the tube is for a true, straight alignment. 

The first picture shows how little glue was used.

After the glue dries, slide the three glued rings off the tube.  

The diameter of the centering rings will be too small for a good fit in the BT-52 tube.

Using a glue stick, I wrapped some cardstock around the rings to build up the outside diameter. The ends were then sanded flat.

Here's a good fit in the BT-52 tube.

Don't glue the engine mount in place yet -

Centuri Skylab Build, #KB-4, Part 2, Parts Fitting

The 3" long BT-20 tube is notched for a standard engine hook.

The inside of the nozzle doesn't have a relief slot for the engine hook.

A square diamond file cut a notch for the hook.

Don't go too deep, the top of the nozzle is thin.

I marked the inside notch with pencil so you can see the fit through the plastic.

I can now slide the nozzle over the engine mount tube without distorting the tube.

No glue yet, there are more pieces to dry fit.

Centuri Skylab Build, #KB-4, Part 1, Parts Fitting

I have to wonder if the Thingverse 3D designer made the pieces fit to Estes tubes. The two pod nose cones and nozzles fit a BT-20, but the nose cone and main nozzle fit a tube slightly larger than a BT-50.

The large nozzle bell didn't fit a BT-50, too small at .976" diameter. The older Centuri ST-10 tube was 1.04" diameter. 

I didn't have any ST-10 tubing. Before ordering parts, I always check the spare parts drawer.

I found some BT-52 tubes left over from an old Thor Agena B build. One piece was 7 1/8", the other at 11 5/8" long. I checked the nose cone and the shoulder fit was good in the BT-52.

Strange thing about those two BT-52 pieces of different lengths. The kit used two 9.4" lengths for a total of 18.8". These two pieces when held end to end were exactly 18.8"! 

The smaller rear engine pod nose cones and nozzles fit a BT-20 perfectly. Two pod BT-20s are needed at 2.95" and a engine mount tube at 3" long. 

The BT-52 tubes will have to be joined together with a coupler. I don't think one is available to order.

Here's the fit of a BT-50 coupler showing a loose fit in the BT-52 tube end.

The coupler diameter was built up with some cardstock wraps and a glue stick.

After the coupler was sized, I tried a standard BT-50 and it would work as a coupler! Oh well . . . 

Centuri Skylab Build, #KB-4, Background

This has been one of my "bucket list" builds. 

I've wanted to tackle it for years but the vacuform wraps and nozzles always held me up. I do some vacuform canopies but nothing this detailed.

The Skylab kit was available from 1972 through 1981. It stood 24.5" tall and retailed for $4.95.

After Centuri was absorbed by Estes, the nose cone showed up occasionally in some Estes kits.

To see the original Centuri instructions: CLICK HERE

I ordered the Thingverse parts (CLICK HERE) from a commercial 3D printing company. The 3D parts were smooth and well produced but fit the Estes, not Centuri tubes. This required some shimming of parts.

This build is going to be different. The first few posts will cover adjustments so the mismatched parts will fit together. This happens sometimes when making a clone model.

Estes Mini Bomarc Clone, Kit #TK-5, Finished

 

This build brought back some 1970s Mini-Brute memories.

Will it be stable? I'll know when I start launches again later this year. Right now - it's too hot!

The silver mask on the nacelles was only possible by painting before gluing to the main body. 

The underside is pretty plain compared to the sides.

I'll add the decal trim lines in the future.

I wondered about the Canadian color scheme on this one.

Light gray body with a brown nose cone?

Estes Mini Bomarc Clone, Kit #TK-5, Part 18, Ink Lines?

The instructions show "ink lines" over the wings, stabilizer and rudder.

How can these be drawn? I thought about using a extra fin point Sharpie but it would be hard to control. 

On a Mini Bomarc build in the 1970s, I drew the lines with a fine point Rapidiograph pen with mixed results 

The lines were added to the decal art.

It'll have to wait until I print some more decals and sneak these in on a page. These will be added to the model at a future date.

Home print decals and fin templates are available to Patreon subscribers. Email me at: oddlrockets@bellsouth.net 

and ask for the Mini Bomarc decals.

This is the same idea used on the line decals I drew for the 1/70 scale Estes Saturn 1B tower details. To see the capsule instructions: CLICK HERE

How could you possibly draw these fine lines over curved surfaces?

Here's how those escape tower decals looked when applied. 

I'm hoping for clean details like this on the Bomarc.

Estes Mini Bomarc Clone, Kit #TK-5, Part 17, Those White Backed Decals

On the right side, 

the white decal has been set down. Let dry.

On the left,

The maple leaf ring has been set over the top of the white decal.

For the Canadian flag decal,

I used a strip of masking tape for alignment.

Set the white decal, let dry.

On the rear tube is the smaller maple leaf circle white underlay.

All the decals in place.

The 6312 number decal is centered underneath the flag.

The French decal on the right side.

English goes on the opposite side.

Estes Mini Bomarc Clone, Kit #TK-5, Part 16, Those White Backed Decals

From the original kit instructions,

Here's the decal placement.

There is some white in the background of the maple leaf circles and the Canadian flag.

I used one of my white decal layering tricks to get the right look. A clear decal sheet is sprayed with gloss white paint. White spray paint is all that's needed, no clear coat. 

This makes a water transfer white decal.

After the white paint dries - 

Over a bright light, set the sprayed decal sheet over the home print decals.

Trace the white areas needed lightly with pencil. Trace just inside the blue ring.

The white under the Canadian flag should be a good rectangle right up to the red border.

The round white circle can be inside but still covered by the thick blue ring.

While the Mini Bomarc Paint Dries -

I used the only brown I had on the Mini Bomarc nose cone - Rusto Custom Spray Enamel. One of those new cans with that crappy "5 in 1 custom spray nozzle". The paint is still tacky after two days!

While I'm watching paint dry, a new project is in the works:

    

I got the Centuri Skylab 3D parts back from a commercial printer I found on Etsy.

These are resin printed, much smoother than the older 3D printers.

Almost all the original kit plastic parts were vacu-formed. 

At $80.00 (including shipping), it was more expensive than I would have liked. I don't have a 3D printer.

In the lower right is a "docking collar". Two are needed for the build, I was only sent one!

I've messaged the printer and a second collar is being sent out.

The Centuri Skylab Thingverse page: CLICK HERE

Thanks to Scott Dee for drawing up the 3D parts and  to Kevin Hedspeth for inspiration and answering all my questions about his build experience.

You aren't told on the Thingverse page - but - 

The two pod nose cones and nozzles fit a BT-20, not the original Centuri ST-7 tubes.

The engine mount tube is also a BT-20. A Centuri ST-7 won't slide through the large nozzle.

I don't have any ST-10 Centuri tubes, I found some Estes BT-52 tubes from an old Thor Agena B build.

Hang onto those spare parts! The nose cone shoulder slides smoothly in the BT-52 tube. 

Estes Mini Bomarc Clone, Kit #TK-5, Part 15, Silver Paint On The Nacelles

The front end of the nacelles are masked for silver paint

The silver starts at the rear end of the "P" support pieces.

After spraying and pulling the tape,

I got a clean color separation.

There's not much of a gluing area on the root edge of the supports.

I'm using the thicker Aleene's Tacky Glue to attach the nacelles. The body was masked for a open strip for glue on the body tube.

After that first glue line dried, a fillet of the Aleene's glue was applied.

The Aleene's glue will dry clear and with a semi-gloss. Elmer's white glue dries with a flat finish. Don't use yellow wood glue on a visible glue fillet like this.

Estes Mini Bomarc Clone, Kit #TK-5, Part 14, Color Paint

Paint is pretty easy on this one.

Nose cone is brown, the main body is a light gray.

After these dry, the rear of the nacelle tube is painted silver.

I was concerned about the balsa grain fill on the nacelle nose cone. 

This turned out pretty well.

There is still a masking paper strip on the root edge (gluing surface) of the "P" support piece.

I

The main body assembly is an overall light gray.

The nacelles are ready to be masked for the silver. 

The main body still needs some sanding and another final gray coat.

Estes Mini Bomarc Clone, Kit #TK-5, Part 13, White Undercoats

I thought it would be difficult to get paint around the ramjet assemblies. The main body and nacelles will be painted separately.

I masked off two gluing lines for the root edges of the nacelle support "P" pieces. I shaded the mask strips with pencil to show up better in the photo.

On the right is the inside end of the body tube masked off.

The root edge of the "P" supports were masked off with a thin piece of tape. These were taped down to a scrap piece of cardboard.

The top and sides were spray painted gloss white. 

After that paint dried, 

The nacelle assembly was slid over a dowel and the underside sprayed.

This is the underside of the wing and body.

You can see how difficult it is to get paint coverage on the inside areas.

Estes Mini Bomarc Clone, Kit #TK-5, Part 12, Launch Lugs

The launch lugs are short, two LL-2AM at .37" long.

These were cut from scrap pieces and sanded to insure both were the same length.

Because these lugs are short - 

Hold on to the lug with the tweezers while applying two thin glue lines. While still holding with the tweezers, set the lug in place under the rudder and wing.

The rear lug is even with the low end of the tube.

The upper lug is tucked under the forward tip of the wing. 

I didn't apply glue fillets on the lugs. It's difficult to get a good fill in that tight corner with all the air bubbles that can form.

School Supplies? Rocket Building Stuff!

Save some money - School supplies can are cheaper now than any other time of the year.

This is the nozzle on a bottle of school glue. I wouldn't recommend the water soluble school glue for model rocket building. 

Replace the wide applicator nozzle on your wood glue bottle with this orange, fine point nozzle for more control of the glue flow. 

Unscrew the nozzle at the white collar, wash out any school glue and replace  the wood glue nozzle. It will fit the threads on the wood glue bottle.

I've used glue sticks for cardstock adapters and in carded rocketry.

Using a glue stick can give your more control on a cardstock adapter "glue tab".

Sharpies come in handy for black paint touchups, line details and Saturn V masking. Go to my Saturn V build for more details.