F-15A Eagle 1/144th Revell 2motor PMC

[Micromeister]

Whenever a Squadron Catalog comes in I alway flip right to the 1/144th and 1/100th Plastic models looking for an F-100. one of my favorite Plastic model subjects..alas still not been re-released in one of the smaller scales.

Recently I saw a very inexpensive Revell re-release F-15A Eagle kit. I ordered 2 right away. I've looked at a couple other manfacturers Eagles in this scale but they have generally had Nozzle problems making them a tad to small for Micro Maxx motors to fit. I'm happy to say that is not the case with this Revell kit.

Converting Dual motor PMC's can be a bit challanging, Most folks don't like ducting so the use daul ejecting chutes or streamers coming out the intake scoops. I've never liked that set up as they are prone to hang up on wings and other things usually making hard landing damage almost routine. There is another way but requires a good bit more planning and Fitting work. At this scale it is also pretty cramped quarters. Because of those reasons I decided early that this model will be a Wheels Up fun flying Sport PMC. our Kit comes with 4 sparrow missile external stores that will be added after basic construction and finishing are complete. As always Mass is the emeny so keeping things to a minimum is paramont.

I believe i've documented most of this build. but some things are really hard to show.
*One of these area is enlarging the afterburner nozzles enough to pass our MMX-II motor casings. At this scale we don't have enough plastic in these tiny pieces to allow for a motor tube BUT we can open them up far enough to easily pass the motor cases with a little room to spare.
Another area that just doesn't photo well is the recessed port openings between the motor tube T2+/T2 stops and the slotted overlapping T2+ Stuffer tube.
*Another; Because we are ducting our dual ejection charges into another tube some provision has to be made for sealing unwanted openings while leaving or creating large enough area to pass the ejection gasses without blowing the pressure fit motors out of their motor tubes. We need at least 1/8" of opening on each side leading into the main T2+ stuffer tube. This was done after the tubes are CA & epoxied into a single unit in the model using a fine dremel bit, round needle file and a 1/8" bamboo pointed Skewer stick. After opening these ejection ports at the most forward part of the motor tubes about 1/8" inside the motor stop T2's we round out and oval the ports from the aft end with the skewer stick angling as best we can into the central tube. White glue & tissue "putty" are then used to seal all unwanted openings in all 3 tubes. these stuff must dry over night before blow test can be conducted to ensure we didn't miss any leak points.

Ducting of this type also dictates a lot of excess plastic must be removed for the underside of the upper fuselage half and some from the bottom. it is critical that the motor tubes remain aligned with the direction of travel level with the wings and aft control surfaces. If we Squeeze down the Upper fuselage on the stuffer tube misalignment will be the result.

I've just started downloading the photos of this build. it's going to take a little time to edit and upload.. I'll start with the Box art and plastic parts. adding more as we go. Hope this sparks a little interest in Micor PMC's again. F-104's are really fun to convert and fly, Hopefully some of the methods in this one will open up a few more of the Dual motor Jets.

[Micromeister]

Have a few more construction pics ready.

After enlarging the afterburner nozzles to be sure we'ed be able to actually build this model a quick dry fit rubberband & tape job give a decent idea of what the model will end up looking like and weighing.

Now it's time to do a couple quick cardboard cutouts to get a general idea of where the loaded LCG should end up. It's always best to do two view side and Plan get the LCGs, combine and average them for the best results. Looks like this little jewel will end up balancing somewhere aroundd 2.5625" from the nose for the first flight..we can then add or subtract a little to get the best flight performance.

Now the fun really starts we can drill out and open up motor tube and stuffer areas then remove excess or unwanted plastic from the inside area of the lower fuselage. Always keeping in mind tube alignment with the direction of travel must be maintained. We can also mark the end and overlap or our ducting whick will give us the lengths of T2+ needed for the project.

Carefully cutting and slotting our tubes to duct the ejection gas into the main stuffer. With alignment paramont I used plate glass under the tubes and a tape adjusted piece of basswood to center the twin motor tubes on the stuffer. A little CA and 5minute epoxy fix the pieces into a solid unit.

After overnight curing the duct unit is fitted in the lower fuselage. some adjustment are always needed to get things to line up. With this one a bit more bottom center plastic needed to be ground out. Thank goodness for Dremel 1/2" sanding drums. When satisfied with the alignment the ductwork is epoxied in place. final flush sanding of the tube ends can then be done.

[Saluki]

You have got my attention. I have order a 144 F-15 to give this a try.

Have you had a chance to check out the new 144 X-15 by Dragon?

[Micromeister]

You have got my attention. I have order a 144 F-15 to give this a try.

Have you had a chance to check out the new 144 X-15 by Dragon?

Looked at it but knowing the 130th scale Heller X-15 makes a PERFECT fit for MMX motors, I'm thinking it would require a good bit of aft end distruction to convert so I did not buy... I have a stash of about 8 130th Heller kits should I need to replace my currently flying model;)

I have however been seriously considering purchase of one of the 1/72nd B-52/X-15 combos. 72nd X-15's usually fly OK on 13mm A10-3t's.

[Micromeister]

While the Duct tube epoxy dries we have time to work on the cockpit Nosecone section.
My first though was to open the cockpit tub & scratch build an interior with ejection seat but then decided it would be better for this particular model to smooth out the seam lines and paint it matte black with just a few surface added do-dads inside the canopy. This leaves the entire forward section open to accept whatever noseweight is going to be needed to push the CG forward to our 2.5624" indicated location.

The kits Square plug & socket fit was excellent. Just a little sanding of the side intake buffers make this forward section a natural as the models ejectable nosecone. a 1/2" section of T2 (.246" OD ) tubing is cut to be press fit & epoxied in place after knocking the corners off the Square plug and drilling out an opening to allow filling the cockpit after assembly. I also drilled a 1/32" hole off center to allow a 90lb kevlar loop to be tied into the forward secion without blocking the fill hole.

I'll add some more pics to this post when I get them captioned. Couple more photos to add

[Micromeister]

more test fitting, thinning plastic parts, careful trimming of outer tubing walls etc to get the fuselage halves to mate without distorting the ducting or changing the line of thrust.

Next important openings are the exhaust ports between the forward motor tube & aft end of the overlapping Stuffer tube. A few earlier project have showed we can get away with a little over 1/8" diameter ejection exhaust holes. To open these holes I used a Dremel with small mill end bit to hog out an oval shaped hole about 1/8" in from the forward end of the motor/motor stop tubes penetrating the overlapping walls of the stuffer. It was easier to do the rough hole penetration from the forward end of the motor tubes then using the pointed end of a 1/8" dia bamboo skewer round and angle these hole UP into the stuffer tube from the AFT end of the motor tubes. Could you predrill the holes in the motor tubes? Yes but it makes fit-up alignment that much tougher..I don't do it that way anymore.

Once both mounts are ducted into the stuffer and the Shockline has been secured to one of the motor tubes with the standing end extended out the foreward end of the stuffer we are ready to seal up all the unwanted duct tube openings. MMX to D12's i've found over the years sealing exhaust/ejection tubing can be done just fine with Plain old Elemers White Glue and fine Tissue, Aircraft cover tissue used to be my standard but that's gotten so darn expensive, I've switched to plain old white Packing tissue, in a pinch i've even used facial tissue. Here we're using packing tissue. torn apart into tiny pieces then mixed with a few drops of White glue into a fiberous Goo. Work the mixture well to break up as much of the clumping as you can then liberally apply into and around the openings to be plugged. work the material well making sure there is plenty of material in contact with the tube openings. Smooth out with a wet finger and/or toothpick. Set the assemblies aside to dry overnight. This stuff becomes a very tough flame/heat retardant solid.
While stuffing this material in the forward ends of the motor tubes be sure to use our wet skewer to maintain the openings. It's OK to block or Slant some of the open area in the motor stop with the plug mixture as long as it doesn't extend or block the motor tube openings or motor length when inserted.
Next day we can check for leaks by inserting a straw or blow tube in one motor mount & a good motor in the other. Ee should be able to blow a hard air stream out through the stuffer tube from both motor mounts.

F15's have those darn undercupped wing tips that make thrust line (direction of travel) alignment hard to judge. My method was to use the nose tip as the point of reference keeping the thurst line as close to parallel as I could.

[Micromeister]

Happy with the air flow through the ducts it's time to recheck the NC & shoulder fit after stuffing 30" of 90lb kevlar in the sealed tube.

Now it's time to close the fuselage, MC solvent welding makes this chore a breeze. All the time spent altering the interior made fit up and final adhearing much easier. DO note it is necessary to flex the last little bit toward the vertical tail areas into place as we glue. Some additional sand/shaping will be necessary at these points before prime/painting.

A little info about Solvent Welding: For those who can't find Methylene Chloride it's sold by the Gallon through most Industrial Sign Suppliers. For those who for some reason don't want to use the very best solvent welding agent (MC); There are a couple decent alternatives available in smaller quantites from a number of sources. From Our Local Hobby Shops, I understand Tenax-7R is being discontinued.. but Plastistruct Proweld is just as good. If you want a bit more of an industrial strength material Weld-on 3 or 4 will do a very good job, available from McMaster-Carr & other Industrial Suppliers. or for those who don't care as long as it sticks.... available from at just about any Home improvement or hardware store, Acetone or MEK solvent weld styrene about 10 times better the Testors Liquid cement which I strongly suggest NOT using for any structural building in PMC's. It's OK for use on static models or if the project really needs a solvent welded bond go with any of the others above.

Both vertical tails went on without issue, care should be observed getting the left and right sides selected properly..the Parts are not identical.

Since I chose to make this a Wheels Up, In flight configuration we'll have some sanding and re-shaping to do on all 5 pieces wheel well doors. Solvent welding then gentle 320 grit sanding brings the underside of the model into pretty decent shape.

our Afterburner nozzles are also MC'ed in place with spent motor casings ensuring exact alignment with the recessed motor tubes. Be sure to slightly twist the casing before pulling them out after the styrene has reset.

I left the 4 sparrow missiles on the motor end of their Spurs, carefully nipping off the other connections and gently sanding the bodies so I can paint them on all sides at once. After painting I'll nip off the spurs then use a tiny dremel bit to open the nozzles recesses just a tad then add it dab of matte black ot the interior.

Last internal addition is the 1/2" x 9" yellow military grade Teflon Tape permanent wadding/Streamer. This will be Talc Baby powdered both sides before roll folding and inserting before the shockline which helps extend the life of the kevlar.

Before getting into the finishing; our kit clear canopy needs just a little sanding adjustment for a better fit. I'm still looking at what minor additions will be added to the cockpit "tub" area.....just an ejection set back and helmet?.... we're still deciding.
the tub area will be liquid masked before priming and painting to ensure a clean raw plastic to canopy edge so our canopy adhesive has the best possible joining surface. Next stop the Basement for a light primer coat.

[Micromeister]

She's gunship Grey now, working on the underside lighter grey.
I'll be adding Titanium to the afterburner nozzles along with some flat black in and around the Cockpit and nose area.

[Fe Dude]

:cool: where do you launch these guys?

[Micromeister]

:cool: where do you launch these guys?

I'm a Narhams Club member, we "normally" have a monthly launch the 3rd Saturday of the month..weather permitting in Mt Airy, Maryland at the Old National Pike Park. Check our website www.narhams.org to be sure. and the 1st sunday of the month we fly at Goddard Space flight center, in Greenbelt. GSFC has a very small recovery area, but we've been hosting the open house public launch there for more then 35years now. I see your from Maryland....come on out and fly with us.

Micros, I also fly across the street from my Townhouse in the small national park running along the ridge above RT 295 in far southwest Washington DC. The park is only about 100-150feet wide but runs almost 2 miles long. unfortunately the prevailing breeze almost always flows the short way.

To be honest just about any small open field works wonderfully for flying Micro's.

[Saluki]

Just received my Dragon 1/144 X-15 and thought you would like to see these pic. The detail on the model is great and you get two complete X-15 models in each box. I have looked through the parts and it looks like you can build all versions of the 3 X-15. The decals are good also but the yellow NASA strip for the tail is missing.

Micromeister I think you need to get a few of these. The MMX motor looks like it will fit. There is enought room for a motor tube.

[Micromeister]

Just received my Dragon 1/144 X-15 and thought you would like to see these pic. The detail on the model is great and you get two complete X-15 models in each box. I have looked through the parts and it looks like you can build all versions of the 3 X-15. The decals are good also but the yellow NASA strip for the tail is missing.

Micromeister I think you need to get a few of these. The MMX motor looks like it will fit. There is enought room for a motor tube.

10-4 Saluki!
I'll have to give them another look! From your posted pics looks like they will make excellent micor PMC's.

I picked Up a Dragon 1/144th Bell-X1 two model kit with my last plastic model order. Alas while it is a Super detailed two model clear acrylic molded body kit. it's going to be WAY to small to convert for flight. Another of those Looks good til ya open the box models.

Thanks for the tip.
Edit: Ordered a Dragon 1/144th X-15 kit at lunch time;) Thanks again for the heads up.

[Micromeister]

A few more photos of the progress on this little PMC.
The kit suggests the model to be white with red/white&blue decals supplied.
I'm going with a USAF paint scheme Gunship & lit Gull Greys. I may have to print some different decals or I might just use a few supplied still haven't made that decision yet.

After a single coat of cheapy auto primer and quick sanding I Painted the underside of the model with light gull grey then while still wet flipped the model over gaving the upper surfaces and both Tails a good coat of Gunship gray. Trying not to get to much overspay on the underside I kept the angle Up but apparently not quite high enough while filling in a few of the "side" exposed area. a few of the intake areas will need some Brush touch up after I try to "Finessit-II" remove some of the unwanted over-sprayed on the Lt gull grey bottom areas.
This is a Sport flying model so I didn't bother masking anything as an experiment. If I'd kept the angle just a bit higher I think it would have worked a better though I'm sure a bit of brush work would still be necessary on the intake ducts. After letting the paints dry over night Finessit-II did remove a good bit of the over spray but touch-ups are still necessary.
While I was at it I brush applied Titanium to the Afterburners which I'll weather a little later when doing some of the other brush applied painting.
Matte blacked out the Cockpit tub area so the canopy can be applied a bit later.

[gdjsky01]

very cool and educational thread! Thanks for taking the time! :handshake:

[Micromeister]

very cool and educational thread! Thanks for taking the time! :handshake:

Thanks Jeff:
It's been a fun build...now I'm hoping she flys well... never know until the first flight with these undercut wingtips.. If I got the thrust line correct she should Scoot on twin MMX-II's.

Catching up over the weekend the 4 little Sparrow missiles were painted, and applied. Got the decal on and remembered to add some launch lugs. OH I'm getting very bad about that! did some brush touch ups here and there and give the final paint a coat of 1309 UV Matte clear krylon before adding the canopy.

[Micromeister]

After the decals, UV Clear and Clear G-S caonpy glue set the model was ready to set the Nose weight. motors installed & Attaching a sting with blue painter tape to our mark 2.56" from the nose clay was added to the nose & canopy area until we got a flat horizontal hang. The clay was removed, weighed and converted into #9 lead shot which was carefully dropped into the hole left in the nose section shoulder adaptor. Sorry I didn't take photos of this operation as it's really pretty boring. Once the shot is in place a small amount of 5 minute epoxy is dripped onto the opening setting the shot solid as far forward as possible. String is re-attached to check and confirm the calculated CG is where we want it.

Ready for her final Still shots before test flying hopefully vary soon.

[[POW]Eagle159]

dang, THAT IS NICE! :wink:

[Micromeister]

Thanks for the Kudo's

Here are the stat's Pics for this fun fly'in little 2 motor micro PMC. Hope to get her in the air shorty....Totally Winded out last weekend with 20 -45mph gusts.

[Micromeister]

Saturday's launch afforded a change to put the Micro F-15 Eagle on the pad.

Careful preperation was observed even went so far as to use some left over 10.5mm motor pyrogen tipped igniters instead of my own MMX Q2 igniters dipped in my pyrogen....in hindsight I should have gone with my own dipped igniters.

Anyway! got her on the pad, hooked up count down and only one motor lit...DEEEEEEEEEEE Rats!
Two concerns arose...
A. at 18.1grams LOWT... one MMX-II didn't even MOVE the F-15 a little.
B. At ejection the model nose did not eject.

I may have the nose taped a bit too tightly but even so we may have an ejection problem? Guess I'm gonna need to do a ground test of this ejection system with a single motor.
have some photos i'll uplaod a little later.

Ps. this also bring some REAL concerns for our almost complete F-14 Tomcat which just weighed in at 22.3g less motors... our F-15 Eagle w/o motors is 17g. ugh!

[hammer]

Looks nice.

[Micromeister]

Looks nice.

Thanks Hammer:
Hope it fly's OK with two motors on the next flight:) I'm back to using my own dipped Q2 micro igniters.

[hornet driver]

Sweet! Very nice indeed

[Micromeister]

Sweet! Very nice indeed

Thanks HD!
Did you get a look at the F-14? She's all but done as well.. Just REALLY Heavy!

[hornet driver]

YEP!! BEE-YOU--TEEE--FULL. I tried the other spelling with just the letters and just could'nt do it----being a Tomcat and all---By the way---AIM -54---OUTSTANDING!