Aero-naut A-10

[Gary Binnie]

Warm, windy and dry, ideal conditions for sanding in the garden.

 

Spent some time looking at different coverings and checking whether the plastic parts are affected by dope or thinners (seem to be ok).

 

In the end I've decided on lightweight StarSpan tissue for the tail parts and fuselage and heavyweight tissue that came with a Veron Vortex kit (I covered that one in film) for the wing.

 

Last photo before covering.

 

[john stones 1 - Moderator]

Looks great Gary. ?

[Gary Binnie]

I've left a few bits off, wing fairings and wheel nacelles (and the props!).

 

The Liteply internal structure of the wheel nacelles is functional and I'm worrying about gluing it on over covering but to do it any other way would be very hard work.

 

Must admit to starting my next project, promised myself that I wouldn't build anything else this year!

 

 

[Dwain Dibley.]

Just read and caught up with your build Gary, I have to say, it's an absolute Beauty Mate, the way you got all those parts to fit with shut lines that would grace a Rolls Royce.

Well done, I am looking forward to seeing her covered, so don't quit now Matey.  

D.D.

[Gary Binnie]

Cheers, very kind words.

 

In trade training I was required to make aircraft sheet aluminium and steel block parts to a tolerance of 0.2 mm using hand tools (files mainly), in the real world I don't think I ever achieved that but wasn't far off.

 

I retired a year ago after 14 years in two Formula One wind tunnels where a portion of my job was to fit wind tunnel model parts (50% and 60% scale), sometimes making them from scratch using sheet carbon and metal. The parts had to be perfect first time and made quickly, quite stressful.

 

The F1 experience has certainly changed my approach to model building plus my skill level is a bit higher than when I started.

 

In the lockdowns I changed my approach to building slightly by not accepting something that wasn't spot on and correcting it or even doing it again. There was no need to rush and all the time in the world to do it right.

 

I have a little goal to build each model better than the last, it mostly happens (but not always!).

 

Tissue covering is a different kettle of fish! I always used to pass uncovered models to my dad! 

 

 

[Silver Wolf]

Hi Gaz,

 

Very Nice, hope to get and see you soon. Need to retire and catch up with some building ?

 

SW

[Gary Binnie]

Cheers O silvered one!

 

     Retire and become busier than ever!

[Gary Binnie]

Tissue covering:

 

I couldn't put it off any longer! I've done more tissue covering lately as I got fed up with film bubbling, I covered a whole Xtra Wot in glass cloth recently to avoid using film.

 

Have had good results with Sig Koverall on gliders but it would be excessive for this model and has a fabric textured finish (coz it's textured fabric!).

 

I discovered StarSpan tissue and covered an Airsail Voltimer with it. It has good wet strength, can be soaked in water and squeezed into a ball and unfolded but does tend to stick to itself so I tend to tack it to the structure or edges of sheet parts and spray it lightly with an atomiser.

 

The lightweight (9 grammes sq meter) is a little bit too fragile for larger models, the Voltimer has lots of patched holes. It shrinks with water and shrinking dope, on the Voltimer I didn't thin it enough and it pulled the fuselage longerons in slightly. All a learning curve.

 

I use Humbrol cellulose dope as I was given several large tins of it, I bought a small bottle of Poly C to try recently but not seeing good results with tissue.

 

1. The Voltimer.

 

 

2. It picked up a small hole in the wing recently, damaged in the car. I moved it to safe place between the front seats then promptly put my elbow through it! Have run out of orange so it will stay like this for a while.

 

 

3 and 4. Back to the A-10, thought I would tackle the tailplane first, brushed with 75/25% dope/thinners and lightly sanded. Attached at the trailing edge only with the same dope mix then folded round and doped again at the trailing edge. I had dampened the tissue before attaching it.

 

 

 

5. Tissue tightening up as it dried.

 

 

6 and 7. For the fins I tried a different technique of attaching the tissue dry using Pritt stick round the edges, trimming and further sticking down with the dope mix on the edges only then water shrinking both sides at once to prevent warps. The fins were pre-doped like the tailplane. This is less messy/fiddly and seems to be working. 

 

 

 

8 and 9. After spraying with water mist the tissue sags and wrinkles then tightens as it dries out.

 

 

 

10. Final step is to follow up with two coats of the dope/thinners mix. The tissue sags and wrinkles again but not as much as with the water and is drum tight once dry.

 

[Gary Binnie]

Who knew that such a small model would take so long to cover?!! Been at it all week including today, I went out for F5J practise on Wednesday.

 

The StarSpan has a habit of wrinkling on sheeted areas even when water shrunk and doped. I used a method similar to glassing, scraping the dope along and over the creases (flattening them) with an old credit card.

 

Used the heavyweight tissue from the Vortex kit today for the wing, best method  I found is to hang the tissue from a wire using clothes pegs, light spray mist of water both sides then laid on the model and doped only around the edges.

 

Tomorrow should be the last day of covering (just the top of the wing and the tips left to do).

 

1. Covering the fuselage, nine separate pieces were used.

 

 

2. Lower outer wing panel, heavyweight tissue dampened and doped around the edges, has just finished drying.

 

 

3. The opposite panel after the first coat of dope, I tacked this panel round the edges dry then water shrunk, the first method was better! All the slack came out thankfully.

 

 

4. Did the centre lower in one piece, could have used two split down the middle.

 

 

5.  Lower surface covering complete, I have just fixed the servos in place so should be a sprint to the finish line tomorrow!

 

[Danny Fenton]

I have tried several ways and laying damp tissue down, and sticking the edges with dope, while keeping the tissue damp and wrinkle free, has always been best for me.

Cheers

Danny

[Gary Binnie]

Agreed, though I will have forgotten next time I come to do it!

 

Had another push today, finished covering the wings (including ailerons and tips where I used the lightweight StarSpan).

 

Without stopping for breath I moved on to the plastic wing fairings.

 

1. A photo I meant to post yesterday, hanging a sheet of tissue to water spray.

 

 

2. Covering the upper centre section.

 

 

3. I noticed the dope changing colour due to rust in the tins so I've decanted it in to a glass container. I was given this dope and several more tins, the labels look like they are from the 1980s.

 

 

4. Checking the wing still fits and gluing on the wing bolt ply plate (not a kit part).

 

 

5. Gathered together the wing fairing parts that I had roughly prepared earlier.

 

 

6. The ply plates glue on to the wing seat.

 

 

7. Protected the wing from stray glue with film backing.

 

 

8. Fitted the wing, I had drawn a pencil line to mark the fuselage side in case the ply base slid out of position.

 

 

9. Added weight to stop it curling up.

 

 

10. Jobs left to do are finish the wing fairings, assemble the engine pods, fit the main wheel nacelles, fit the tailplane, fins and elevator, then think about painting.

 

[Gary Binnie]

A half day today, had to take Mrs B for her second COVID jab.

 

Finished the wing fairings, a little bit fiddly, both ply bases needed trimming, mainly at the front.

 

Next job was to glue on the centre section fairing, as the ply wing seat bases changed how far the wing bolted in to the fuselage it wouldn't have lined up if it was already glued on.

 

Last effort for today was on trimming the finger grip 'buckets'.

 

1 and 2. Fitting the wing fairings, short triangular ply pieces fill the rear ends. The steel rule is simulating the wing, holding the bases flat.

 

 

 

3. On to the centre section fairing which needed more trimming as the wing doesn't bolt up so far now.

 

 

4. The finger grip 'buckets'.

 

 

5. They are quite thin and easy to cut (and easy to cut too much off!). I wondered if they should be cut flush with the wing skin all the way round but a fuzzy black and white photo in the German version of the instructions shows them being cut like this.

 

 

 

6. There is a gap between the buckets and centre fairing which I had noticed before.

 

 

7. The gaps will be filled by strips of scrap plastic.

 

 

8. The scrap plastic came from the moulding of the nose skid (for the wheels up version), took me ages to work out what this non-scale bump was for! The other mouldings there are air cooling inlets (NACA ducts) and outlets.

 

 

9. I was curious about the gaps in the finger grips and wondered if my sloppy building was to blame. The fairing cut out width is 50 mm.

 

 

10. The distance between the outer faces of the ribs/inside of the cut outs is 53 mm.

 

 

11. The plan also measures 53 mm across the outer faces of the ribs and the ribs are positioned by the pre cut slots in the spar and the Liteply parts so I'm not guilty!! Would have thought that this would have been caught during a beta build, not the end of the world, just curious. 

 

[David Ashby - Moderator]

Nice work Gary.

[Gary Binnie]

Cheers, the rainy weather is keeping me in the shed!

[Gary Binnie]

Just a short session today, patience/skill shortage!

 

Finished the finger grips, might need a spot more filler after primer.

 

While the wing was on the bench it was logical to move on to the wheel nacelles. These are quite tricky (IMHO!) consisting of a Liteply frame and an upper and lower plastic moulding. It's not clear to me at the moment what the best way to build them is, the structure could be glued inside the lower moulding and glue both to the wing or the structure could be glued to the wing etc, etc.

 

Both halves of the moulding share the horizontal part of the structure so the joint needs to be accurate (the instructions mention filler, I wonder why?!).

 

Taking a short break from it, might watch 'Ice cold in Alex' on the box, it's on most afternoons!

 

Otto Lutz

 

1. Finger grips mostly done, I will stick some sandpaper in here after painting.

 

 

 

2. Liteply structure of the wheel nacelles, roughly in position.

 

 

3. Short, top half of the moulding. It has to be trimmed to fit nicely with the leading edge and structure/lower half of the moulding.

 

 

4. Bottom, long half of the moulding. If the model is built with undercarriage a hole needs to be cut for the leg to pass through.

 

 

[Gary Binnie]

Well, I left this build for just over two weeks but it's not been abandoned yet!

 

I wasn't 'feeling it' and general gloom and doom with constant wet weather wasn't helping.

 

Since then I had several days F5J practise (got sunburnt) and flew the two-day F5J Radioglide competition at the NFC (got sunburnt again!).

 

A height limiter trace below shows an interesting flight where I almost landed then scraped away to complete the 10 minutes, model was a 3.8 metre span V-tail NAN Explorer.

 

The shed needed a massive tidying session which took three days, it was at the point where I had no space to work.

 

Back to the A-10: I had lost my way a little bit with the undercarriage nacelles but I eventually realised that the more difficult/important moulding to trim is the small, upper one. With that trimmed fairly close to size I have just glued the Liteply structure to the wing, I think this job will get easier now.

 

1. F5J flight trace.

 

 

2. Overflowing paint, glue and dope cupboard!

 

 

3. Emptied out, empty cans thrown away then repacked.

 

 

4. Model storage rearranged (this is after the tidy up, honest!!)

 

 

5. A-10 wheel nacelles, upper part trimmed fairly closely to the finished shape and size.

 

 

6. Gluing the Liteply structure to the wing.

 

 

 

 

[Gary Binnie]

Plodding along!

 

Wheel nacelle thingies are finished, look ok from a distance!

 

Now on to the engine nacelles, I had trimmed one of the inner plastic parts the wrong way around but managed to salvage it.

 

The expanded foam nacelles have to be covered with paper as they are quite unfinished/rough looking. The instructions don't say what kind of paper but the German instructions say 'bespannpapier' which is covering/tissue paper and 'Glutofix' is to be used (sounds like the porridge we had in the RAF!).

 

I bought a small bottle of Poly C recently and I think it's the ideal stuff for fixing the tissue to the foam as there is no reaction.

 

1.   Fixed the top half of the wheel nacelles.

 

 

2 and 3. Then the lower half, gluing area was increased with balsa strip.

 

 

 

4. Out in the sun, trimming the retracted 'wheels' to fit.

 

 

5.  Trimming is a bit tricky as there are curves in all directions.

 

 

6. On to the engine nacelles, it's very difficult to get the upper pieces the wrong way round (front to back) but easy to mix up the lower pieces (doh!). The longer, shallower taper is the jet pipe end.

 

 

6. Brush painting the internal bits, one side Airfix acrylic, the other Humbrol 33 enamel (I remember all the colour numbers from the 1970s!). My master plan failed as I didn't paint the insides of the foam pieces before I glued them on!

 

 

7. Gluing the nacelles on with UHU Por.

 

 

8. A cutting plan for the paper covering is given in the German instructions.

 

 

9. I started from inboard upper and worked on quarter segments. Pritt stick to anchor the edge then Poly C, this does make the tissue wrinkle but they can be smoothed out with fingers (like dope but without the smell!). 

 

 

10. At the rear end I will trim the paper flush, at the front I have wrapped it around the intake lip. It's an interesting technique that I've not used before.

 

 

[john stones 1 - Moderator]

Looking the part Gary, some tricky bits done there.

[Gary Binnie]

Have to admit it's been a slog just lately, a lot of tricky bits done in a row.

 

I'm over the worst (I think!).

 

Itching to start the next project.

[Gary Binnie]

Two months later...!

 

I have been very busy with DIY, house/loft/shed/garage clearouts, new Combi boiler, house rewire and a big family wedding.

 

I'm part way through putting a new roof on the shed but the next settled weather spell is not expected until next week.

 

Taking stock in the shed I spied a lonely A-10, it really is almost finished.

 

Initially forgot where I was with it then remembered that the second engine pod needed covering (which I've just done).

 

Have just attached the first fin to the tailplane using epoxy, the plan shows dowel reinforcements or another option to have the fins removable using bolts.

 

 

 

[Gary Binnie]

A little more done today, not far off painting and finishing.

 

Epoxied on the tailplane assembly making sure it was square to the wing and level.

 

The elevator was tape hinged before gluing the assembly on, the clevis was fitted to the screw seen in the pictures and slid down the carbon pushrod (epoxy applied) with the radio turned on and the elevator sub-trim neutral.

 

Added the balsa block fairing that I had made earlier but hadn't tissue covered.

 

Trimmed the tail cone fairing for the elevator.

 

Had a couple of goes at fashioning a six-barrel cannon, its fairing has to be carved from balsa. Tempted to leave it off as it might get caught in the grass but it is a feature of the A-10 and people will ask where it is!

 

Weighed up again and it is somewhere around 1,125 grammes which is something like 350 grammes lighter than the lightest Ni Cad powered version, still some paint and nose weight to go but not much.

 

CG with the battery fully forward is around 90 mm (95 with the props fitted) so it will need a touch of noseweight to bring it into the range of 78 to 82 mm.

 

1.  Gluing the tailplane on.

 

 

2. Adding the balsa block and plastic tail cone.

 

 

3. I spotted earlier that the elevators have a fair gap to the tail cone, will probably correct this (my error, not the plan).

 

 

4. An attempt at the cannon, phenolic tube with lengths of plastic snake outer and a length of carbon tube in the centre.

 

 

5. Risky shot in the garden, rocking around in the wind.

 

 

6. With props fitted.

 

[GrumpyGnome]

Looking really good .......... 

[john stones 1 - Moderator]

Ditto, nice cannon Gary. ?

[Gary Binnie]

42 minutes ago, john stones 1 - Moderator said:

Ditto, nice cannon Gary. ?

 

Cheers! The cannon should have seven barrels, not six, I was thinking of the M61.

 

Looking at photos it doesn't really have much of a fairing, more a larger tube that it sits in which might be easier to make.

 

I worked on F-4 Phantoms for quite a while, it could carry a six barrel cannon in a pod on the centreline, known as the SUU-23. We used to get lads to visit the armoury and ask to speak to 'Sue Gunn', oh the mirth!

 

 

[Gary Binnie]

Plodding along on a rainy afternoon.

 

Getting a bit of 'finish it itis' as I do want to get stuck in to the next project.

 

Tidied the rear of the engine nacelles with some card rings.

 

Trimmed the gun to shape and epoxied it to the plastic nose cone, hopefully it won't get snagged on landing.

 

Corrected the elevator to fuselage gap and fitted the tail cone.

 

Filled some small gaps and holes here and there, nothing left to do except paint now.

 

1. The rear faces of the engine nacelles are a bit untidy and not exactly circular either!

 

 

2. Made some card rings, I love playing with the circle cutter!

 

 

3. Not perfect but better than they were.

 

 

 

4. Trimmed the gun.

 

 

5. It needed to be concave to match the nose profile so it had a short blast on a drum sander.

 

 

6. Epoxied on. The pencil line is off centre, not the gun!

 

 

7 and 8.  Corrected the elevator gaps and fitted the tail cone.