Howard Metcalfe F15

[Gary Binnie]

Live from the shed!

 

I have epoxied the tailplanes into position using a method similar to the instructions (using a sheet of balsa as a straight edge to set their dihedral at zero).

 

I placed a spirit level across the wing spanwise and added the left tailplane only, making sure that was zero. After the epoxy had set I added the right tailplane using the left as a datum, clamping a strip of hard balsa across both.

 

While the epoxy was setting  I thought it would be a good idea to add the graphics to the fins before they were fitted. Quite pleased with how they've turned out.

 

Next step will be adding the wing gloves.

 

1. Gluing the right tailplane on after the left had set, clamped with balsa strip across both (Liteply load spreaders underneath to avoid clamp damage).

 

 

2. The 20 to 25 year old self-adhesive graphics were in good condition and still very much useable.

 

 

3. Having a look at the fin graphics, I wondered what to use as a datum to line them up and decided that the top edge of the fin should be used, the tailplanes are set a few degrees nose down relative to the wing incidence where the real F-15 appears to be zero/zero.  The base of the fins sits on the tailplanes.  I've drawn on a rudder with a 6B pencil, I bought it recently and it's my 'go to' pencil now (doesn't score soft balsa).

 

 

4. I do like to get things straight and even doing this it sometimes goes wrong! I'm using a drawing from Tamiya plastic model instructions as a guide.

 

 

5. A pair of handed fins! 

 

[Gary Binnie]

Time to stop for today, the wing gloves need trims in various directions and I don't want to cut or file too much off accidentally.

 

Weight now is 1570 grammes (3lb 7 oz) minus torque rods, receiver and battery and some small bits and pieces.

 

1. Looking at the wing glove fit, a trim of the wing slot moves the tailplane and fin slots, a trim of the tailplane slot moves the wing and fin slots (etc, etc, etc!!)

 

 

2. Needed a little trim behind the wing to allow the aileron torque rods to pass, same trim both sides.

 

 

3. I cut the upper part of the gloves off where it passes over the wing, I was trying to avoid this to save a joint but it was necessary.

 

 

4. The cut out parts will have tabs each end, Velcro is provided in the kit to hold them on. As the model will fit easily in my car in one piece I might tape the panel joints and edges on final assembly.

 

 

5. The top hatch appears to have warped upwards since moulding, I tried weighting it down over a few days which didn't work. Might try some gentle heat, experimenting on some scrap plastic first.

 

 

6. The ailerons have been left slightly oversize in span, once the wing gloves are fixed I can trim them to give clearance at both ends then cover them. I've just wedged them in here.

 

 

7. Getting there slowly. The fins are just dropped in and leaning towards each other as the wing gloves have to move inboard slightly yet.

 

 

Edited May 22, 2022 by Gary Binnie

[Gary Binnie]

Some more progress today.

 

Finished trimming the wing gloves and glued them on.

 

Glued the left fin on, will leave it to set overnight.

 

1. There is small gap in places between the wing gloves and fuselage, I've wiped in a fillet of aliphatic resin.

 

 

 

2. More wing glove fixing.

 

 

3. Made some simple jigs for alignment of the fins, might look like an extravagant waste of highly valuable balsa but woodworm had been busy on this piece!

 

[Gary Binnie]

Just a short session today.

 

Added the second fin and they are both vertical and square to the wing (yay!).

 

Trimmed the ailerons to span and covered them.

 

Fixed the aileron torque rods.

 

1. A trimmed and covered aileron, I keep wanting to call them flaps as that's what they are on a real F-15!

 

 

2. Gluing the torque rods in.

 

 

3. Maybe it's obvious or maybe it isn't but it's better to put the glue in the hole or slot rather than putting it on the piece to be glued in, this 'eureka' moment came to me a couple of years ago!  I used a cocktail stick to drip epoxy into the holes.  

 

[Gary Binnie]

The weather was ok today to do more spraying in the garden, I finished off the grey and added some silver near the jet pipes.

 

A lot of masking, my main worry was over spraying the graphics on the fin and paint lifting with the masking tape, luckily neither happened.

 

Jobs left to do now are:

1. Hinge the ailerons and elevators.
2. Make and fit Plasticard covers over elevator servos.
3. Fit the cockpit parts and find a pilot.
4. Fit the canopy.
5. Add tabs to the upper wing glove strips
6. Paint the jet pipes.
7. Add the remaining graphics.
8. Add receiver and battery, set balance point.
9. Range test, fly.

Photos:

 

1. I used the wing and top hatch to mask off the insides of the fuselage and carefully masked the fins.

 

 

2. Sprayed and dried quite quickly.

 

 

3. Flipped upside down to paint the bottom.

 

 

4. Going well so far, just a few greenflies decided to visit and get stuck.

 

 

5. There are bare metal sections of the fuselage for the hot zones of the engines, I found some alloy wheel silver that I use to paint the final drive of my motorbike. I read the label and it said it contained acetone so I tried it on a bare piece of plastic first in case there was any reaction, no problem.

 

 

6. The problem with masking is that you don't find out that you've missed a bit until you take it off!

 

 

7. Came out better than I expected!

 

 

8. Same deal with the top hatch. I have Tamiya masking tape but standard DIY tape worked well.

 

 

9. All good.

 

 

 

10. Very happy that the graphics didn't get over sprayed and there is no hard line where it was masked.

 

 

11. Light at the end of the tunnel!

 

[Gary Binnie]

A bit chilly outside today so I pottered in the kitchen.

 

Ailerons and elevators fixed, radio set up with some initial travels.

 

A few more graphics added.

 

Looks like I will be able to set the balance point just by moving the battery, at the moment a four-cell NiMh pack under the cockpit is working.

 

1. Quite an awkward thing to balance, pencils taped to tins works, 300 mm along the leading edge from the wing glove for the glider version, 230 mm for the power version.

 

 

2.  Battery under the pilot should be about right.

 

[Murat Kece 1]

?super

[Gary Binnie]

Did some pilot shopping this morning and found one that looked perfect but I backed out as it was from the EU with warnings of Fed Ex charges for collecting VAT etc.

 

Made, fitted and painted the Plasticard covers for the tail pieces of the fuselage.

 

Fitted an on/off switch and volt checker, both accessible through the open jet pipes. I have telemetry on my transmitter for Rx voltage but I do like to see old school coloured lights as well!

 

Went searching for foam to pack out the nose to place the battery, apart from not finding any foam I thought this would be fiddly and an imprecise way of doing it when I remembered that I used to set CG position on an F5J glider by mounting the flight battery on a stick so that it could be moved fore and aft. I found the stick (just a thin strip of ply with Velcro)  and also the glider ballast weights, a combination of brass and aluminium threaded rods.

 

So...I have a battery on a stick now and just need to work out how to make it adjustable, at the same time I will make a ballast mount.

 

1. This open area is to be filled with Plasticard.

 

 

 

2. Like this...

 

 

3. I sprayed the aerosol paint into a used yoghurt pot (a clean one!) and used a brush to touch in.

 

 

4. Looking at the radio gear, the receiver will be fixed where it is.

 

 

5. An on/off switch and volt checker.

 

 

6. The ballast system and battery stick from my NAN Xplorer 4000, the holes in the end of the aluminium pieces allow the ballast to be placed optimally for CG.

 

 

7. The Xplorer 4000 (4 metre span) for interest, luckily the wings de-rig into three pieces for transport! I have 3.5 and 3.8 metre versions of this glider.

 

 

8. I made a Liteply stick for the battery and need to work out how to vary the fore and aft position and fix it, pencil behind the ear time!!

 

[Gary Binnie]

Spent all day designing and making the movable battery and ballast system, it's fun 'winging it'! One day soon I would like to design and build a simple slope soaring glider, something I've never done.

 

1. The movable battery clamp is built on a piece of hard balsa sheet that came with the kit, it will fix to the ply reinforcements inside the fuselage and also be bonded to the floor of the plastic moulding. I had a sheet of unidentified hard wood in my scraps box, I think it is Obechi. Using that I made two 'runners' and a clamp. I drilled for, and epoxied in, two M3 brass inserts to take machine screws. I use these instead of self-tappers on cowlings as they are much more durable. I added a 2 mm scrap of Liteply to fill the gap between the clamp and the battery strip, the gap was 1.8 mm so this was 0.2 mm too thick.

 

I did think of adding a square of sandpaper to the packer to help the grip but it wasn't needed.

 

 

 

2. With the screws lightly nipped the strip is secure, marvellous!

 

 

3. Part B of the project was to work out how to fix the ballast bar, I started with some very hard balsa rails to locate it fore and aft. I also cut slots for Velcro straps, I use a lot of these, even replacing cable ties on my motorbikes as they are kinder on the paintwork. 

 

 

4. The whole system. I will have to add an extension to the rear of the strip as all this will be under the wing and not easily adjustable. My plan is to leave the clamp just slightly loose so I can move things then tighten fully to lock it. Another thought is that the battery will need some foam top and bottom to fix it vertically in the nose otherwise it will swing like a bell clapper.

 

 

5. I then realised that the cross rails would stop the battery strip from being removed so I cut the centre parts of the rails out.

 

 

6. There is room for a second ballast bar and it would also be possible to stack it over the first one.

 

 

7. I kept thinking how odd the CG position given in the instructions was as I have almost always used the leading edge at the root for full-size weighings and models. It struck me that if I joined the two leading edge marks with a straight edge or piece of string that it would give a position at the roots, the two pencils are pointing  at them.

It's something like 190 mm aft of the datum (leading edge at the root) but will confirm that when it's next assembled.

 

Edited June 1, 2022 by Gary Binnie

[Gary Binnie]

Slack day today, mowed the lawn and put some bunting up under supervision.

 

I was in despair for a pilot when I remembered that there is a vacform one in the Fw190 kit that I am building. I found it and apart from having goggles it was about the right size.

 

The two halves of the vacform didn't fit very well so I glued them to a 1/16" balsa  core and cleaned it up with files. Not perfect but a magnitude better than what I could have carved from scratch.

 

Sprayed the inside of the cockpit area which was another little job that needed doing.

 

Have started painting the pilot with ancient Humbrol/Airfix enamels, some of them must be 30 years old or more and are still quite usable after a good stir.

 

1. The vacform pilot from the Fw 190, I think it is 1/10 scale. Now I have no pilot for that model, will cross that bridge when I come to it!

 

 

2. Looks about the right size, he couldn't see the instruments so I broke the glare shield off and shortened it.

 

 

3. Masking up for the cockpit area, I really didn't want any overspray at this stage.

 

 

5. Perfect conditions for spraying in the garden this afternoon.

 

 

6. Getting there.

 

 

[Gary Binnie]

Pushed on today as I was feeling that the build was dragging out, pretty much finished.

 

Glued in the ballast system.

 

Glued in the pilot and fixed the canopy.

 

Painted the jet nozzles.

 

Set the balance point.

 

1. Ballast and adjustable nose weight arrangement glued in, added a tail of hard 1/8" square balsa so that I could move the battery with the wing fitted.

 

 

2. Glued the pilot in, don't look too close! Better than an empty cockpit.

 

 

3. Fixed the canopy on with strips of aluminium tape.

 

 

4. Masked up for brush painting.

 

 

5. Frames added with pre-painted tape strips.

 

 

6. Painted the jet nozzles, first silver then a dusting of black.

 

 

7. Adapted my Multiplex CG rig by taking the stops and balance weights off to use it as a pivot, I had to move the battery back a fair bit to achieve balance. Weight RTF is 1,860 grammes or 4 lb 2 oz.

 

 

8. Pretty much done, might paint on some nav lights and anti-col beacons, I am toying with fitting the sensors to the top of the fins but they could catch in the grass at the slope.

 

[MattyB]

Really nice finish, great job. I jsut hope after all that work the performance is satisfatory - the only one I ever saw slope was a brick, it was great off the sea in smooth, turbulence free air but rubbish at all the inland sites the owner tried. I hope you have a big hill! ?

[Andy Meade]

That's looking super Gary, great job!  Looking forward to a flight report when you can (big SW this weekend btw!)

 

[JasonA9393]

I had one of these which I tried to PSS. It now resides at the bottom of the Atlantic off the coast of Wales. I'm amazed you've even got one of these kits in this day and age: I thought it was a 1990s thing?

[Andy Meade]

A few still appear on the BMFA ads every now and then - people clearing out lofts I guess?