Scratch Building a Mercury Marlin

I was having a rare attempt at tidying my aeromodelling paperwork. The shed wasn't just cold, it was snowed in. I couldn't solder up some battery terminals indoors, only because I've a thing about LiPos turning themselves, without warning, into something hot and nasty. So I rummaged through an accumulation of old articles from magazines, tatty old plans barely discernible on yellowed paper, and too fragile to use. Then I found a big buff envelope with a readable plan of a Mercury Marlin in it. I never built the model years ago as I never got hold of a suitable engine. The plan sat in the envelope, completely forgotten. Fast forward to 2013 when i was given a box of "old junk" from the estate of a late model flyer. The "old junk" consisted of tins and small jars holding a bewildering assortment of screws nuts and washers, mostly rusted into lumps. Wrapped in oily rag were two engines, a boxed (with all papers) Mills 1.3 Mk2, and an unwrapped Elfin 1.8. I thought perhaps the Elfin might be used in a suitable C/L model, if I ever got round to building one. It wasn't until the plan turned up last week that I remembered the Elfin. No doubt that without the snow which prompted my "tidy up". This little model would never have been started. It took quite a time transferring the shapes to balsa sheet, but its rewarding starting from scratch,
I'm cheating a bit by copying bits of the plan on my HP Scanjet, and I'm cheating by using a balsa knife rather than a single edge razor blade, aliphatic glue rather than balsa cement and a Perma Grit sanding block rather than sandpaper wrapped round a piece of wood.

My God Brian, that takes me back, I built a Marlin when I was about 14, a very handsome airframe, elliptical wing (just like a Spitfire in a small schoolboy's mind), powered by an Elfin 1.8. It was my pride and joy I'd love to do another just for old time's sake. My Elfin was stolen from the apprentices modelling room along with quite a collection of my other engines when I was "serving my time" at Bristol Aero engines 1954 - 19959. From memory - Amco .87, ED Bee, ED 2.49, Elfins 1.8 and 2.49, Frog 100, Frog 500 - my first glow motor -, 2 * Mills 1.3 and a .75 - what would that lot be worth now?
I made a slight change to the plans adding coupled inverse flaps, it would "loop on a sixpence" (for the uninitiated - flaps operating in opposition to elevator)

If I built one now I'd cheat too - Profilm covering rather than the blue parachute nylon with which my Marlin was covered.! I wonder if Carbon Copy would make us a canopy for it.

The Elfin 1.8 also powered my unlimited see pic - no laughing please.

Good to know that the model is familiar David. I don't know if I can manage it but I'm going to make a canopy from a plastic bottle. Last one I made was for a KK Skystreak 40
but that's another story!. I'm modifying the top of the fuselage to accept a "bubble" canopy, much easier to plank too. Your engine list more or less matched mine. The most awkward engine at the time was my Frog 160 Red Glow. Once started it went very well, but starting was always a problem with it. Recently I sold my original Amco .87, the proceeds will keep my models going for most of 2018. Don't think the Elfin would have been quite so popular with the bidders. I wouldn't laugh at you with the Unlimited, at that time, I too wore "roomy" trousers......... with huge turn-ups. I used to keep them under control by wearing cycle clips. Showed off my yellow socks a treat! Want the plan when I've finished the build?

Yes please the plan would be great (so would a set of parts when you start cutting them out!)

I have an early OS40 Four stroke, it should fit the Marlin nicely. My only problem will be finding someone to fly it, one of the problems with old age is the "three laps and all fall down" syndrome. I'd be ok with a combat model - just flying continuous 8's!

Worth looking at this website www.model-plans.co.uk
The guy running it has around 40,000 files Inc the Marlin & may be able to supply a parts kit.
Colin

Thanks Colin, I think that's where I found the Marlin plan. Don't remember the cost but it seemed reasonable at the time. I did have some fun with the chap that runs the website. I bought a "genuine" KK Skystreak 40 plan and print-wood patterns. When the plans arrived, the main drawing was a re-drawn copy, and the print-wood was a crude hand traced affair, all wobbly lines and not very accurate either. After some haggling I ended up with a copy of Bill Dean's original plan, and copies of the actual print-wood taken from photos of the real thing. The whole business must've cost the poor chap quite a lot of money in the end.

Good to see such a variety of building going on at the moment. Will be good to see all these projects finished in the next few months.

I'm wondering if trying to build the Mercury Marlin was a good idea after all. I'm now on the second "go" at building a wing. Taking for granted that the printed parts are accurate led to all sorts of problems with fitting things together. Half the trouble was that I'd cut narrow spar slots in the ribs. After easing them out, the rib lengths didn't match the wing plan. This, coupled with the fact that I'd got an error of 3mm (!/8" in 1950s measurements) in the profile of the trailing edge, made it a difficult job to get the parts aligned accurately. Looking back seventy years, I'm sure I never had this sort of problem. A tube of balsa cement and a handful of my Mum's dressmaking pins seemed to be all that was needed. Perhaps all this CNC and laser cutting has made me forget the basics. No pics of this stage, I'm too ashamed of the mess.

Oh dear! Never mind Brian. Weathers improving so get that MX out and flying.

I was going to make a start on the Phase 6 soon when the other half let's me have "MY" workspace back but no rush now, virtually no slopes to use.

Brian - What you had forgotten that many of the early plans were not really plans but a guide to help you build
something that looked similar.
I spent many happy hours on Mom's kitchen table recutting bits of balsa to fit .

Colin.