Jump to content

Piper Cherokee 140 conversion from an Airfix Piper Arrow - Detailing


Recommended Posts

I started this some 25 years ago as 16YO glued the wings together and for some odd reason, cant remember why, hacked off the nose forward of the windscreen and that was as far as it went. Its been sitting in my parents garden shed ever since.

Seeing Tripods Warrior has given me some inspiration. http://www.britmodeller.com/forums/index.php?/topic/234936765-fun-with-cherokees/

Now work has restarted the dust, dead spiders n eggs have been cleaned off and its going to become a Cherokee 140, this one to be precise:-

1223420M.jpg

Stephen Powney/www.abpic.co.uk

I owned a share in it over 10 years ago to hours build and clocked up over 100 hours in it, Built in 1968 and great fun to fly, cheap too I think I managed to get the hourly cost down to £25 if I flew it very carefully at min drag speed around 70kts clean and leaned the mixture, great for loitering around South Lancashire & Winter Hill on a sunny weekday evening after work, clocking them hours up towards a commercial licence.

For a conversion to from Arrow to Cherokee I think I need to make or mod the following.

New nose - scratch built

New spinner - scratch built (prop blades from kit, might need to shorten them though)

Shorter wings

Shorter stabilator

Block up the rear windows

new undercarriage & spats - scratch built (kit wheels)

Remove the dorsal fin from the tail

Wings & stabilator was shortened, Airfix have made this easy to cut in the right place from the surface detail just remove the bit between the ailerons and wing tip fairing, similar for the stabilator remove the bit between the anti-servo tab and the tip fairing.

8645724767_d928af0a81_c.jpg

8646819932_70f922a5e3_c.jpg

a new nose is to be built, must have had a premonition of this when I hacked off the old one all those years ago. I started by drawing out the new shape cowl in 1:24 scale from photos and drawings the scanning it and rescaling to 1:72 then printing several copies onto a sticker that was placed on 2 laminated sheets off 1mm plasticard. The holes for the 3 air intakes were cut out first by drilling small holes then fileing the rest to shape, this I had some trouble with as even my needle files were too big and needed a re think. Just when I was on the verge of considering crash moulding the basic shape out of thinner plastic, I was in Affinity Models in Stoke, and hey presto micro needle files £8 for a set of 10!. So yesterday was spent making the cowl.

With the holes cut out the main shape was cut, filed and sanded from the sheet. A 4mm disc was cut from 0.5mm card for the crank wheel with the starter motor pin from 0.5mm plastic rod. the whole thing was laminated onto another piece of 0.5mm card and the baffles fitted in the engine cooling holes.

The landing light was made by thinning off the end of a length of tube with a file and sand paper then fitting into it piece of rod with the end smoothed off and rounded, then cut to the appropriate length (0.5mm) and fitted in the air filter recess.

8645726297_c674950337_c.jpg

8645726419_ebfb545bd1_c.jpg

Might need to do a little repair on the crank wheel

8646823988_a7640b69fc_c.jpg

The undercarriage bays were filled in by thin layers of filler leaving each one to set before the next. The rear windows were also filled in, The windows were cut from the main 3 window transparency part and used as a backing for the filler.

The storey so far :-

8646823984_2d6433c6ec_c.jpg

Thanks for looking

Mark

Edited by Cheshiretaurus
  • Like 1
Link to comment
Share on other sites

Hello Mark , it is nice to see another conversion! I still don't know how you guys can see things like this. Also, yet again it is an education - I never knew you could get micro needle files, and they are something I have needed for a while.

With you having had a share in the original aircraft, it just adds that personal touch to the project.

I will keep looking in, and hope to pick up some more tips. Great going so far.

All the best, Ray

Link to comment
Share on other sites

Ray,

The needle files I got were these set 72536 from Expotools http://www.anticsonline.co.uk/892_1.html

Heres a pic to show you the size with a normal 160mm file for comparison

8646960851_034833a845_c.jpg

As far a seeing is concerned, I got a pair of +3 reading glasses from ebay for a couple of quid, without them I'd have no hope. Bright desk lights help too.

Edited by Cheshiretaurus
Link to comment
Share on other sites

From one Cheshire lad(also a Mark) living on the border to another,this looks very good.

I guess(from the sound of it) you did your flying at Lancashire Aero Club,

I did mine at Shropshire Aero Club(Sleap),they too had a 140(G-ASXT seems to ring a bell).

Link to comment
Share on other sites

Hello Mark you have just given me another excuse to visit Antics in Gloucester! Thanks for letting me know where to get the needle files.

Kind regards, Ray

Link to comment
Share on other sites

Miggers, yes did the PPL at Barton and instructed there too for a while before becoming a turboprop driver for a living, Took the Cherokee into Sleap a few times, had a near miss with a glider there too, he had seen me first but carried on milking his right of way........

Ray, your very welcome.

Link to comment
Share on other sites

I love the new cowling, it's a sublime piece of modelling

And now of course I HAVE to have some of those little files

:(

Wonderful work I wanted to convert a Cherokee Arrow myself years ago but lost the urge before I got any research done :thumbsup:

And that might just happen some time in the future thanks to your thread

bill

Link to comment
Share on other sites

Nice start. Just a suggestion , you could have filled the windows an undercart bays with scrap plastic card and only a smear of filler.

I do have a photocopy of the 1/72nd plans taken from a Scale Models article several years ago. They show a number of other Cherokee possibilities. Like The Cherokee 6 which was a stretched version with fixed and retract undercarriage. If yourself and others here would like a copy, PM me and I'll sort them out.

Link to comment
Share on other sites

Paul,

Did think about using scrap plastic but the old windows were just a convenience as already the right shape and was just simpler to keep adding filler bit by bit as I was working on the nose at the time. Scale plans would be useful, thanks for the offer I'm using the plans from a pilot operating handbook and scaling photographs at the moment, Do you have them scanned? might be easier to email them if you have.

Mark

Link to comment
Share on other sites

A little more done

I've made the spinner from laminated rod and tube from a Slaters pack held together with CA, conveniently they fit within each other and a short length of about 3/4" was made but with only a few millimetres of the core fitted this was to save drilling a hole later for the hub to fit in.

8646960145_c34a9e5c46_c.jpg

I then put this in the chuck of the drill to file and sand to shape, and just as it was about complete, it all separated, not sure why maybe it got a bit hot from friction. Re-assembled and left overnight It needed some filler, more sanding and a final polish with micromesh. The end was cut off by spinning it in the drill with a scriber, bit more polish on a cocktail stick and I finally have a spinner.

8658691592_9e9f2baf45_c.jpg

Looks about right, just needs holes drilling to locate the blades in.

8657587065_d19701d8b8_c.jpg

Ive made a basic frame for the cowling from plastic card, the voids will be filled and shaped with milliput.

8657584605_6a7f5d6457_c.jpg

Just need to make some final checks on dimensions and angles, but after measuring and remeasuring from a 'side on' photo that I have scaled I think its about right. Things are only bluetacked together at the moment.

8657583425_b493826bac_c.jpg

In the meantime I printed off the spats in 1/12 scale from the scaled photo and traced out a line drawing of them, re-scanned them back in then re printed them in 1/72 onto a sticker. This was then stuck on to a laminate of 1mm plasticard making a 3mm block and filed out the basic shape ready to sand to a 3 dimensional profile.

Also need to work on depth of field technique on the camera too!

8657588169_bd9d5f3cdb_c.jpg

8658695070_6c672e7f49_c.jpg

I'm only making 1 main wheel spat and 1 nose wheel as I have this great plan of vacuforming them in 2 halves to make them hollow for the wheel, but this is a while off.

Tonights task is to make a RTV mould to cast a copy of the nose as I don't want to risk the master while making the rest of the cowling so some spares might be up for grabs at some point as well as some other parts I intend to cast for it.

  • Like 1
Link to comment
Share on other sites

Great work!

Your spinner looks very good. I have done the same but I used sprue instead. I always save the thick ones!

On the spats, you could have laminated 3 sheets, with the internal one void to accept the wheel. You could then enlarge the hole easily if needed.

Something similar i did:

th_Gull-spats-05.jpg

Carlos

Link to comment
Share on other sites

Hi, I too had a share in G-PAWL from 2004-2006, got quite a few hours in it myself, including a trip to Old Warden where they made me park next to the Sea Hurricane. Such hardships! I have just been in my loft and found a Minicraft 1/48 Cherokee and also a Guillows kit for a flying balsa model. If you would like these they can be yours for a donation to the North West Air Ambulance. PM me if they are of interest to you.

Link to comment
Share on other sites

It is looking good so far

I am another "mould the spats instead of carving holes in solids" fan, worked a treat for meon my Sherpa

I wouldnt have used CA for the tube assembly though, some thickish liquid poly cement would have been my choice, Revell Contacta seems to work quite well in these circumstances

Co-incidentally, at the mo' I'm building up my five bladed props this week. First one in its spinnerglued solidly so I have a template for the other four at 72º apart... I wish I only had two blade to deal with

:)

lovelywork on yours, ta

b

Link to comment
Share on other sites

The former light aircraft engineer in me is stunned with what you have achieved!!!

Only saw 2 or 3 -140s pass through our workshop but we had -161 Warrior IIs in our fleet! Dont think i can follow your lead to replicate them!!!

Arabest,

Geoff.

Link to comment
Share on other sites

Thanks for the comments chaps

Carlos

I never thought of that, I'll keep that in mind as the back up plan, going to continue with plan A of vacuuming them as it would be good practice for me on the technique. but ill keep your idea in mind, thanks. that spat of yours looks good, is that a proctor kit you've used looks like a Mewgull?, have 3 in the stash I'll have a good look at what you've done there.

Paul J

Sent you a PM, Thanks

Phil Ogden

Think I sold my share around 2000 when I started instructing and no longer needed it, have you got any pics of the interior? I seem to remember the seats were a light greensish grey with red lower interior side walls or am I thinking of another aircraft? from my log book st1 flight in it was 16/5/98 and last one was 31/1/01, But I think that was in my in my instructor roll and had sold the share a while before. Have 119 flights in it but don't know the total time but seem to remember I'd done over 100 hours in it.

Edit 24/4/13 just added up my flights in it 105:30 total time on G-PAWL - The power of Microsoft Excel!

Perdu

I remember reading a scratch building article from a chap making the master patterns for the Welsh models EMB170 or 190 kit and it being mentioned that for laminating to use CA as poly can take days to set, appreciated this was a large thick volume he was working on, so prob would be irrelevant to my small spinner any way. but we live n learn, ill try poly next time.

Good luck with the sherpa props been looking at it, that's some good work gone into it.

Jazzie

Thanks, have intentions to do a warrior too!

BigBadBadge

Might be able to help you with the windscreen I'm planning on vacuuming a new one for this based on the old one so could have replacement for you, I'll see how I go with it.

Mark

Edited by Cheshiretaurus
  • Like 1
Link to comment
Share on other sites

Carlos

that spat of yours looks good, is that a proctor kit you've used looks like a Mewgull?, have 3 in the stash I'll have a good look at what you've done there.

Mark, the spat is for a Gull IV and yes, I am using the Proctor kit as a basis. It is not much advanced than in the photos, but in between I have more documents and will proceed when time permits.

Link to comment
Share on other sites

Had a few days away with work so not much been done, I've made mould for the nose and was going to cast a resin copy this morning for temporary fitting to establish the shape at the front of the cowling. however things were not going to go smoothly with the resin in simple terms I couldn't get the lid off, It was bonded on. Even after mechanical brute force no joy. The resin had probably had it anyway it was 2 years old and there wasn't much left.

I could order some more resin but I'm going on holiday at the end of the week so would probably turn up while I'm away. Had a look round to see what I could cast with.

Herculite - too brittle, too long to fully dry, not good with water for wet sanding,

Plaster of paris - worse,

Gelcoat - not the right application, and being able to breathe would be useful.

Milliput - hmmm, this might work pushed into the mould left in the airing and by lunchtime it had set enough to use. detail didnt transfer very well but I only need the general shape.

While it was setting I completed the plasticard frame for the cowling

8666475722_fcff853753_c.jpg

I've spent the last few hours filling in the voids with more milliput and smoothing out with water, think I have the shape right.

8665454465_cd2d6dbd94_c.jpg

A while back I made a modellers equivalent of a plasterers trowl for this purpose, I find it very useful, its just a bit of T shaped aluminium with a piece of plasticard stuck on that gets polished every so often.

Once its done ill remove the nose, its only temporary stuck on and replace it with a proper cast one.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...