Junior 60 Refurb

[PatMc]

I'll be posting some photos with comments along the way as make progress in the long overdue refurbishing & electrifying my Junior 60.

The model was made from the Flair kit in about 1986. It had a number of mods built into it, has been flown using a variety of glow engines, diesel engines & for one flight an unsuitable electric set-up. Most of it's life power has been an old type OS Max 25 but this was changed to an un-run OS 25 FP (one of a pair that I wanted to run in for a twin project) some time in 2004. It was flown over a few months with this engine before being stored in the loft until I retrieved the fuselage yesterday.

It's apparent from these photos that the Solartex covering is very grubby from exhaust residue & general use over it's 18 year active life not to mention 8 years in a dusty attic.

Whilst in the attic it was subject to a little mousework on the rear top longeron & underfin...

unfortunately the twisted rear fuselage is more serious & will take a bit more work to rectify. This was due to the being stored with something under the left tailplane so that there was a constant pressure for years.

First jobs have been to remove the engine, fuel tank & tailplane then strip the Solartex from the fuselage. This was completed today more pics to follow

 

Edited By PatMc on 04/10/2012 23:19:17

[Greybeard]

An interesting project, I look forward to following your progress.

[Mike Etheridge 1]

Patmc,

My Junior 60 I built originally in 1962/3 also needs a refurb. The black Humbrol paint has pickled around the nose section and needs stripping off. I have bought some black fuel-proof spray paint to repaint the nose section and it's just a matter of getting round to doing it. However if you keep this item going I will try to keep up with you. I must say your plane looks in far better condition than mine,but it's a shame your fuselage has twisted. At least the Solartex should come of easily.

MJE

[Mike Etheridge 1]

Patmc,

Just thinking about your JR 60 twisted fuselage, I assume twisting it straight and then applying a heat gun will not do the trick?

MJE

[PatMc]

Mike,

I intend to strip all the Solartex off then appraise the state of the whole airframe before attempting to straighten the fuselage. I will probably use a wallpaper stripper (steamer) to heat the framework and attempt to twist it straight again.

[PatMc]

Rudder & elevator use pull-pull with pivot arms at the servo end so that there's no load on the servos when not in use. There's also a pivot arm at the tail with a short rod to the elevator horn.

Taking the tail off just involved releasing the rudder clevises, undoing an 8BA securing screw & releasing the internal elevator clevis.

Screw is accessed by swinging rudder to one side...

and put back so it doesn't get lost.

Engine out next ...

then the litho cover underneath...

revealing the oily thing ...

and when that's out ...

the tank's redundant.

Edited By PatMc on 07/10/2012 20:24:44

[PatMc]

Now to find out what's underneath.

General condition not bad apart from twist to tail end.

I'll need to add some extra bulkheads to take an electric motor. There's some oil on the bearers but after surgery there should be enough clean wood to take whatever's needed.

Both control linkages look OK. Fresh clevises all round should take care of that.

[PatMc]

Now for the wings.

The top surface is in fairly decent nick ...

but decidedly grubby below. The round patches cover holes made to drain water out caused by Jnr flipping over several times whilst taxying during a waterplane event. The other wing didn't take in any water at all.

After 25 minutes stripping ...

generaly good condition ...

except for this. Probably the result of the aforementioned water intake.

Both wings have a slight warp resulting in some wash in. This should be easily fixed with a little steamwork before re-covering.

[PatMc]

I've been considering what electric power set up to use. Since the model will cruise around most of the time at low power but will need some avoirdupois in the nose region for the cg I had considered using a brushed motor with gearbox. By coincidence the combo weighs almost the same as the OS 25 plus lump of metal in one photo.

Depending on how I re-construct the nose the electric motor might fit OK but of course there will be about 6.5 ozs extra to be added for a 3s 2200 lipo. So I may instead plump for brushless outrunner that will swing an 11" or 12" prop & locate the lipo as far forward as possible.

As a matter of interest I saved all the Solartex that was stripped off & weighed it - came to. The fuselage & tail came to 74g (2.6oz) the wings another 84g (3oz).

[PatMc]

I haven’t had much spare time in the last 4 months but I did got things moving again recently & finally have some progress to show .

The wings were still in generally good nick so after checking all joints for integrity a few parts spar webs were replaced. The minor warps were easily fixed using the wallpaper stripper/steamer then a light sanding saw the wings ready to be covered.

The fuselage twist took a bit more effort with the steamer & some serious jigging but it’s now straightened out. A few spacers needed replacing &/or re-gluing on the rear fuselage but it also was generally in sound nick.

The oil soaked wood around the nose was cut away & fresh blocks grafted in place ready for sanding to final shape.

I had a re-think about the power & decided to use a brushless outrunner on a tailor made ply mount in place of the original paxolin engine plate. The lipo will be positioned near vertically under the windshield area with access via the cowl top. The ESC is to be mounted on a liteply shelf under the motor.

[Bob Cotsford]

That's an ingenious solution as it's totally reversable. Very neat.

[PatMc]

Bob, it wasn't intended to be reversible & the verical part isn't actually central between the screws. However button magnets have been set into the cowl top to match up exactly with the 2 front screws.

In these photos the fuselage just needs a little more of the red removed to be ready for re-covering.

And here the rudder & elevators have been attached using “Ultimate Hinge” so they are also ready to be re-clothed.

[David Davis]

Very neat work.

[Braddock, VC]

This thread is a great spur for me as my j60 needs a dose of looking at as well as my southerner major, can't see myself electrocuting them though.

Nice to see a racer powering a j60, my original one in the mid fifties had one, but without the mufflers, for some reason I can't remember what happened to that plane, yet I can remember eachof the others I built and destroyed.

[Mike Etheridge 1]

The mufflers were added to my Junior 60 when the use of silencers became 'the norm'. I was surprised at the time that they were manufactured by ED and when I purchased them I was also able to buy a plastic bodied RC throttle / back-plate /rear disc for the engine. The good thing about the Racer is that it will only cut-out in the air when the fuel runs out. As I have mentioned before the Racer has identical bearer fixing hole spacing as an Enya 19, so they can be inter-changed very easily.

MJE

[PatMc]

Junior is now ready for it’s second electric flight. The first was sometime in the last century using a 600 brushed can motor, 6x1200 sub C nicads with a servo operated microswitch for power control.

It’s been re-covered with Solartex but will benefit from some décor once the trimming flights are over. Power is a Keda A36-12L with 3s 2200 lipos, a 40A ESC & control is via two standard size servos.

Fully equipped the RTF weight has gone down from it’s ic days at 1871g to 1725g. Balance point is the same as then at 33mm behind the plan position.

Looks like the grass will need to be cut quite soon but with any luck I should take Junior flying tomorrow.

[David Davis]

You've made a lovely job of it Pat.

[cymaz]

great job well done mate

[Mike Etheridge 1]

Well worth the effort!----I bet it will perform well with the new electric drive. One of our club members had an electric Flair Junior 60 it flew very well.

MJE

[PatMc]

Thanks for the encouraging words chaps.

As hoped, I managed to take Electric Junior out for a couple of flights today with NE1 on hand wielding the camera to record the occasion. (Cheers Ken) I also had an HK altimeter on board & wore my Cam-cap for the flights. The weather was near perfect - sunny with slight mist & virtually no wind but cold.
The battery wires were interfering with the removable top cowl so it was left off rather than risk losing it.

When the throttle was opened Junior virtually leapt into the air, a small amount of down trim sorted out a tendency for the nose to pitch up then a few circuits for the camera, later a loop & very barrelly roll. I'm dead chuffed with the result of the refurb/conversion, this must be one of the most relaxing models I've ever flown.

Cam-cap = a Flycam sewn to an old hat perched on an old head. Videos will probably be posted after editing to a reasonable time span.

Low pass for the camera.

Cam-cap in operation.

A ground pose after a couple of successful flights.

Graph of flight #1

and flight #2. The power was cut at the peak recorded altitude. From there the glide time to ground was 1min 48secs giving a sink rate around 3.22ft/sec. Not bad for an old barge with a free-wheeling prop up front.

Total flight time came to 22 minutes from a single battery charge. The re-charge at home took 1860mAH, meaning that the current averaged around 5.1A with the average power level at about 58W.

There's a couple of minor mods to make to take care of the cowl problem & I will probably move the ESC position a little before the next outing.

Edited By PatMc on 06/03/2013 00:44:42

[David Davis]

Well done Pat!

I learned to fly on a Junior 60 and have always had a soft spot for them. As you say they are the most relaxing model to fly.

[Eifion Herbert]

Sorry, wrong tab, mods please delete 

Edited By Eifion Herbert on 02/04/2013 19:36:10

[PatMc]

Here's Junior's first flight with electric power. At Blyth with KenNE1 taking the still pickies & providing a target.

Once I've edited the videos of the second flight & one of the Veron Deacon I'll see if it's worth posting them.

[Jimbo565]

very nicely done for a silver fox,the aircraft and flying spot on but the photographer ??????

I'm going to have a word with him.

Jimbo ne23 words dept

[Mike Etheridge 1]

Having finished re-building a Super Air I decided I needed another project. Last week or so I re-joined the Epsom Downs club and thought it would be a good idea to dig out my old Keil Kraft Junior 60 and fly it on the downs which I first did in 1963. The plane had not flown for a few years and last year I used the wings on a re-built Super 60. Having dug the plane out of the loft yesterday the first thing I noticed was that the ED Racer was gummed up such that the propeller would not turn,so the first thing I did was to take the engine apart and immerse it in methylated spirits. The black Humbrol paint on the fuselage which was painted on in about 1977 following it's first refurbishment was totally pickled so I started to scrape it off but the clear dope came off the nylon as well. The dope was also flaking off the unpainted part of the fuselage so there was no alternative but to strip off the nylon with a view to re-covering the fuselage with red Oratex which I had used on the Super 60 previously.

The ED Racer now turns over nicely and has had a thorough clean. The wing platform / cockpit structure has fallen apart and needs repair, and I hope the 52 year old balsa is not too impregnated with diesel fuel such that the Oratex will not stick?

I must add an elevator / tailplane this time which I could borrow from a Ben Buckle version of the plane but unfortunately it is the wrong colour.