Catching Pictures in the Air

[Fritag]

24 minutes ago, perdu said:

That slab sided old thing behind him?

 

 

 

No no I can see what it is, and intuition works too

 

The corner of quite a distinctive badge on the right sleeve is a bit of a give away too.....

 

 

Altho' RB probably had a few fewer hours......

 

BTW.

 

I for one have never tried the talcum powder in cyano trick - so please feel free to post some step by steps 

[keefr22]

3 hours ago, perdu said:

And really, don't breathe the sh.. fumes

 

In bulk they can do awful things

 

I can testify to that Bill. Used to do a fair few 'commission builds' in the early 90's, used superglue extensively for speed in building them - after a couple of years I became allergic to it & now if I try & use 'ordinary' superglue I have severe 'flu' like symptoms, even if I just open a tube of the stuff. Can now only use odourless varieties without wearing a respirator, & then not for long....

 

Take heed of Bill's warning, Tony.

 

Keith

[TheBaron]

We'll have to do this thematically not chronologically:

4 hours ago, Fritag said:

Now, it seems to that's the smile of a man who's just been low flying in a proper aeroplane........

 

4 hours ago, perdu said:

hell of a guy Mr Baxter

 

4 hours ago, Tomoshenko said:

Raymond Baxter ... top man.

Ain't that so gents...

4 hours ago, Nigel Heath said:

Be warned that talc catalyses the setting of superglue so you will only have a minute or so to work with it before it sets. It does make a nice adherent filler though.

4 hours ago, perdu said:

Tony the goo will go off quickly with the talc in it so be prepared to do small dollops at a time

 

And really, don't breathe the sh.. fumes

 

In bulk they can do awful things

 

4 hours ago, Tomoshenko said:

A word caution Tony (in as much the same vein as washing one's hands thoroughly or wearing gloves after / before chopping up chillies before inserting contact lenses or an amorous encounter) keep the superglue, cotton buds and talc separate. Something tells me getting that lot mixed could go horribly horribly wrong followed by an embarrassing trip to A & E.

 

17 minutes ago, keefr22 said:

I can testify to that Bill. Used to do a fair few 'commission builds' in the early 90's, used superglue extensively for speed in building them - after a couple of years I became allergic to it & now if I try & use 'ordinary' superglue I have severe 'flu' like symptoms, even if I just open a tube of the stuff. Can now only use odourless varieties without wearing a respirator, & then not for long....

 

Take heed of Bill's warning, Tony.

Nigel Bill,Tomo, Keith. Warnings duly noted boys. My thanks. 

3 hours ago, Fritag said:

I for one have never tried the talcum powder in cyano trick - so please feel free to post some step by steps 

I'll do so Steve; there appear to be a number of variations people seem to have used so I might experiment with doing a side or two differently to compare results. That is if I can resolve the potential shape problem discussed below.

 

Boys. I was just having a final look at the build tonight as a way of familiarizing myself with the balsa-shaping task to come, when alarm bells began to go off big-time.

 

Dingalingaling in fact.

 

Have a look first at this rear 3/4 shot from the series of excellent walkrounds of Pelican 9 up on Prime Portal:

On such 'J' variants (which were essentially modified 'F' and 'G' airframes), the sides of the fuselage continue back square all the way to to where the BT joins the fuselage, as seen above, and continue on so to the apex.

 

Now a 'G' version, as in the kit:

Here you can see by the displacement of the final fuselage window that the 'G' fuselage curves inward to begin develop into the contours of the clam shell doors. 

 

When I put 'G' fuselage and 'J' BT together to demonstrate the disparity, it it not a happy union:

A Duckfilled Fattypuss in fact.

 

Hark!

 

Canst hear the sound of Duelling Banjos in the valley?

 

I had another quick check on Gurgle to see if it threw up anyone else who'd tried using this kit to make a 'J' but it seems we're off the map on this one now. No-one to crib from. Abyss staring back etc.

 

I think my observations are accurate, in that the kit curve here matches the necessary curvature of the clamshell doors of a 'G', thus:

But not - unfortunately - the buck I'm making for a 'J' BT door peeking out from below it.

 

I'm frankly embarrassed at having missed this until now. There isn't, it has to be said, a great deal of information about the 'J' variants, either in print or online, and certainly none of the sources I've consulted mention the fuselage being widened at the rear to accommodate the new door design. That's not a valid excuse however for the penny taking so long to drop on this.

 

From the visual evidence then, I can only conclude (please correct me if I'm making a schoolboy error) that the fuselage was widened at least 2-3 stations back from where it joins the tail doors to nearly the main wing spar box, as part of the 'J' modification program.

 

This might also explain why I was finding it such a tight fit between the actuators for the poles and the walls at the back, which baffled me given that the separation between them and the other details like cable tray etc. seemed about right in relation to reference photographs. (Too easy to seek justification in hindsight however. ..)

 

There's a frustrating circular logic to this of the: 'absence of evidence isn't evidence of absence' kind, due to the dearth of information about the engineering details of the modification program.

 

Irrespective of this, the visual and physical evidence is such that there is a real problem here with the build now.

 

The question is - what to do about it? Well for a start, I don't intend giving up one whit, but do need to work out a viable (not to mention achievable with my basic level of skill) plan.

 

Possibly:

 

'We're going to need a bigger buck'....(or even two)

 

What would Jeeves do in such a situation? <cue @perdu>

 

 

To sleep, perchance to have right bleedin' nightmares now...

 

PS. No slagging of Jaguars on my thread please. You know who you are.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[perdu]

Bigger buck

 

Simple kind sir

 

Make a bigger buck, mould more of the fuselage structure with it

 

Back as far as the "place it all went widdershins" 

 

Remove bad bit

 

make good internal structure that inevitably gets a tad 'strained' under the onslaught

 

Separate clamshell's beavers from new fuselage sides

 

fit together to the 'made good' internal structures and roof/floor bits

 

tidy joints and introduce fuselage structural surface details to the new bits

 

and carry on

 

 

(or simply wait for Jeeves to return from carousing at his Club For Gentleman's Gentlemen...  He may be some time. They are celebrating the return of a Rosie M Banks from an enforced sojourn in a cell near Caracas)

 

 

[hendie]

I'd go with what Bill has stated.  It sucks that you only noticed this now - but better now than later.  Hey, we've all been there but most importantly, you are going to do something about it.   Lesser noblemen would have balked and said nowt.

[Brandy]

'Fraid I don't see any other way around it either. A lot of work, but as Hendie said, better to spot it now than later!

 

Ian

[TonyTiger66]

I agree with all above. I think Bill's right. Out with the saw by the look of it.

 

It's extremely scary for such as I, but given your scratching skills, I'm (and I'm sure the 'royal we' are ) you can do it .

 

As you (more or less) say, uncharted waters; but it's exciting to be an explorer and pioneer  

 

All the best

TonyT

 

[Martian]

Although it is obviously frustrating to discover this problem now, I think that although the surgery required looks drastic, it will be relatively straight forward to perform so don't be too disheartened.

 

Martian

[perdu]

A god-given opportunity

 

You CAN do it, we know and in the process you can fix the unfixable poser that was giving you grief up on (in) the roof

 

I'm glad you spotted it now, 'cos its as obvious as a standing out a mile thing that is blindingly obvious that it was going to be awful

 

Now it is going to be ace!

 

I might have tackled it with slab sides of polycard as thick as the kit side walls with rounded upper and lower corners because it might give you a better chance of following the moulded sides

 

I'll be sitting back over here scrounging some of Giorgio's prosecco at odd moments and enjoying the trip, seeing how you delve into the braver new world of pa.. Er enjoyment. 😈

 

 

[CedB]

What a pain tony but better spotted now than later, I guess... I'm sure you'll master the changes and feel much better for it  

[Martian]

Ced's right Tony. After sorting this out, other projects that that you may have considered and then passed over as too difficult might not seem so daunting.

 

Martian

[TheBaron]

Bill, Hendie, Ian, Tony, Martian, Ced: thanks all for your encouragement, understanding and advice gentlemen. It was heartening to wake up and read this morning.

 

A plan is slowly forming in the dense thickets of the Baronial noggin this morning about how best to approach this conundrum on both the structural strength and melding-with-extant-detail fronts.

 

I'll report in later with a likely procedure.

[TheBaron]

Having a morning's liberty to play with, and buoyed by reading your comments over breakfast, I committed to a course of action.

 

A more detailed examination of the airframe at the rear in relation to reference images (primarily the superb walkaround of Pelican 9's tail area over on Prime Portal (http://www.primeportal.net/hangar/weichao_chen/c-119j_51-8037/index.php?Page=4) revealed that we needed to come further back (well, forwards, but you know what I mean...) than I had originally thought last night in order to establish a correct 'slab-sided' aspect, as seen here:

Clock how those sides aren't entirely flat however, but express a slight and diminishing concavity down to a flat aspect at the apex of the BT.

 

Something I need to remain conscious of.

 

Here's where I reckon we need to go back to on the kit fuselage to start matching this:

Which actually  takes us back under the wing as you can see:

Some Dymo tape to act as a cutting-guide as well as preserving (as far as possible) a neat edge to the cut seemed a reasonable precaution:

Out with Dexter for the main incision:

Brutal, ain't it? 

 

I'm not all that bothered about any damage and restoration work required for the interior detailing - there's nothing inside there that can't be easily reinstated with a minimum of angst after all - the main focus here has to be on achieving a decent basis to correctly re-shape the kit.

 

Look away now if you're of a nervous bent:

Having removed the offending areas on both sides, it was necessary also to redo the thick inner walls of the fuselage at the top, in order to straighten the interior aspect in the same fashion. You can see the issue here - starboard one done and checked, port one about to follow:

It was a simple enough task with a small sanding drum on the D-clone, finessed with a hand file to this:

I'm now glad I spent time adding that cruciform strengthening to the upper wing spar as it will come into it's own now on the thinned upper fuselage:

I bunged the floor in for that shot as well to let you see that we'll also have to 'flare' both aircraft floor, cable deck ( that'll be a swine to fix I fear) and ceiling outwards to fit the new boxier cross-section.

 

Is it my imagination or has this build suddenly transformed into a wannabe Ekranoplan again?

Bill, I'd pondered your suggestions regarding both buck and use of thick plasticard and I think that both approaches might be fruitfully combined in the following manner:

Pink regions show here can be constructed from thick plasticard (bent ever-so-slightly by a process I haven't worked out yet) to match the side-issues discussed above.

Yellow regions top and bottom can be plunge-moulded.

 

Or would it remain simpler to plunge-mould the whole thing in top and bottom halves, as an expanded version of the original plan, I want to let that percolate for a few hours now and weigh-up the pros and cons in those procedures.

 

Either way, we're committed to fixing this.

Tony

 

 

 

 

 

 

 

 

 

[perdu]

Brilliant

 

So far you are bang on the button thingy

 

Thick plasticard will bend form quite easily if you grip the 'to be bent' bit in your vice, pray and apply bending moments to the plane side surface 

Two or three practices might be needed but you'll be surprised to find that in many times of playing 'first time's the charm'

[keefr22]

Most excellent remedial work underway there Tony, top stuff !

 

The only thing that would worry me about the combination of thick plasticard/plunge moulded bits would be how easy it might be to glue the two together and then make the join dissappear? I'd be tempted to do the whole tail as a plunge mould as per your original plan & just have the extended fuselage sides in thick placki.. But what do I know, I'd habe been building it with doors closed from the off, so wouldn't have had to worry about making it neat enough for all your lovely internal detailing & could just have lobbed half a pound of filler at it...!!

 

Keith

[Martian]

I would probably go with the thick plastic card sides and moulded top and bottom although I would most likely vacform them.

 

Martian

[hendie]

plastic butchery at its butcheriest!   Gotta love the gore.

 

There's nothing quite like jumping feet first into a pool of uncertainty, and only then trying to figure out how to get out of it - keeps the mind active

 

 

[CedB]

You are a brave and courageous man Tony, it has to be said (although the pink did make me think twice...)

Great stuff - as a motivation I could say that the rest of the assembly is going to be easier (although you'll probably put me straight!)

[TheBaron]

4 hours ago, perdu said:

Brilliant

 

So far you are bang on the button thingy

 

Thick plasticard will bend form quite easily if you grip the 'to be bent' bit in your vice, pray and apply bending moments to the plane side surface 

Two or three practices might be needed but you'll be surprised to find that in many times of playing 'first time's the charm'

Thanks Bill. I reckon with my level of inexperience at fabrication on this scale I'm going to need to experiment to get a feel for the various processes, this one included.

4 hours ago, keefr22 said:

Most excellent remedial work underway there Tony, top stuff !

 

The only thing that would worry me about the combination of thick plasticard/plunge moulded bits would be how easy it might be to glue the two together and then make the join dissappear? I'd be tempted to do the whole tail as a plunge mould as per your original plan & just have the extended fuselage sides in thick placki.. But what do I know, I'd habe been building it with doors closed from the off, so wouldn't have had to worry about making it neat enough for all your lovely internal detailing & could just have lobbed half a pound of filler at it...!!

 

Keith

 Keith, your experience is always welcome here and those are valid concerns. My initial thoughts are possibly to make any horizontal  joins coincide with stringers, though I'll need to take a more detailed look at some photos of that area to be sure that would be feasible. One - not inconsequential - related issue to this is the fact that I was leaving the kit panel lines slightly raised over the rest of the aircraft (rather than sanding off and rescribing), so what to do about mimicking this effect on my mouldings requires some further thought...

2 hours ago, Martian Hale said:

I would probably go with the thick plastic card sides and moulded top and bottom although I would most likely vacform them.

I'm erring in that direction Martian in the case of the sides; regarding vacforming top and bottom sections though, why would that be preferable to  plunge-moulding?

 

Speaking of which...I had the oven heating for the boys' tea just now and thought 'what the hell', promptly bunging in a piece of reclaimed packaging:

I didn't bother doing the job properly vis-a-vis mounting the plastic to a negative blank as this was just a spontaneous 'taster' of the process, never having attempted it before' The hot sheet was simply draped  over the buck after a minute or so at 220 °C and pressed it down with an oven glove to form this:

The Phantom Beaver Tail....

I was genuinely surprised at how well-defined edge of the 'beak' turned out given how unfinished the the surface of buck is. (The now too-narrow buck given the corrected wider dimensions of the rear...) Such results can no doubt be made much better with proper preparation, though I must say that the notion of vacforming plasticard as an alternative also holds an old-school fascination for me that I'm kind of sort of possibly going to need to examine at some stage anyway...lots to ponder now this evening.

 

At this stage it's probably safe - if not blindingly obvious - to say that this build has firmly transformed itself into a long-term undertaking.  Long gone is any pretence at getting this finished before we disappear on holiday at the end of June, plus I'm signed-up for the Flying Boat GB in September and have a model of a VW to do up as a birthday present for my aged mother.

 

We may be talking that male specialty - spatial awareness multi-tasking!

 

(I'm a dead man if Mrs. B reads that last bit...)

 

Ah. Hendie and Ced have just popped up on the screen:

3 minutes ago, hendie said:

plastic butchery at its butcheriest!   Gotta love the gore.

 

There's nothing quite like jumping feet first into a pool of uncertainty, and only then trying to figure out how to get out of it - keeps the mind active

 

My sentiments exactly. Step up to the envelope, push the plate etc.

 

Cutting-off one's retreat can be a powerful incentive!

7 minutes ago, CedB said:

You are a brave and courageous man Tony, it has to be said (although the pink did make me think twice...)

Great stuff - as a motivation I could say that the rest of the assembly is going to be easier (although you'll probably put me straight!)

Hiya Ced, and thanks! Assembly? What is this 'assembly' of which you speak? You don't think I'm actually intending to assemble the kit at some stage, do you?

The Pink Baron

[Martian]

I would vacform in order to get a more even thickness of plastic o Multi-titled One.

 

Martian

[Spookytooth]

Braver man than I tony.

Nice work sorting out the angles etc.

This is turning out into a epic of butchery, first the top area now the back end.

 

At least you are getting there.

 

Simon.

 

 

[TonyTiger66]

Superb carvery there El Baron  

 

A nice thick fillet of rump Boxcar slapped on the plate with new potatoes, fresh green beans and gravy  .

 

It looks quite 'Zen' at the moment. 

 

In terms of time, better to enjoy it and let it take its own time. 

 

The oven plunge turned out surprisingly well. Nevertheless I can't help thinking that Martian is right with vac-forming. It would produce nice strong parts fit for detailing.

 

Do you have some spare wood, an old vacuum cleaner and hose? Now the soldering barrier is well and truly broken and the lathe acquired, it could be time to introduce a home made vac-former to the mix ?

 

Well done on the slicing again: much bravery !

 

Best regards 

TonyT

[Tomoshenko]

Cripes I'm away for a day and you've literally re-invented the wheel, in a manner of speaking. Glad you're goin for it, and to paraphrase an obnoxious corporate soundbite, but nevertheless appropriate, "turning a crisis into an opportunity". Seriously though good stuff and like the "up and at em" approach. Also larger fuselage means more super detailing muhahaha

[Brandy]

Well you didn't waste any time there did you? I was going to suggest just cutting along the corners and bending the rear of the fuselage outwards to get the wider shape, and adding fillets as necessary, thereby keeping the same outer details etc, but too late now, you've gone and lopped it off!  I would think plunge/vac moulding of the rear end will be far simpler than correcting the floor and roof panels too, I'll be interested to see how you decide to go about that.

 

Ian

[perdu]

57 minutes ago, TonyTiger66 said:

Superb carvery there El Baron  

 

A nice thick fillet of rump Boxcar slapped on the plate with new potatoes, fresh green beans and gravy  .

 

It looks quite 'Zen' at the moment. 

 

In terms of time, better to enjoy it and let it take its own time. 

 

The oven plunge turned out surprisingly well. Nevertheless I can't help thinking that Martian is right with vac-forming. It would produce nice strong parts fit for detailing.

 

Do you have some spare wood, an old vacuum cleaner and hose? Now the soldering barrier is well and truly broken and the lathe acquired, it could be time to introduce a home made vac-former to the mix ?

 

Well done on the slicing again: much bravery !

 

Best regards 

TonyT

What TonyT says is so obvious I'm not sure why M. Obvious (moi!) didn't mention it

 

Quel dommage...

 

I built one very cheaply ( I let another club get me some MDF for signs and allow me to collect them after the event they were for)

out of sheet MDF with some PVA wood adhesive

 

Several feet (metres are available for a fee) of gaffer tape were also involved

 

I made it 'so big' and after drilling zillions of 1/8" th holes in the upper surface and cutting a hole to let the vacuum out I made two sets of HOLES for it, one big enough to allow smallish fuselages or wings (I made blanks for my Sherpa which I could have used if the solid wing method didn't work out) and a smaller one to allow canopies to become..

 

Just become

 

Like this, the slot at the front is for vacuum making using my old garage Henry

 

The acetate is held between two outer sheets by drawing pins

 

it works

 

I use the crudest method of heating acetate

 

Gas blowlamp

 

eeek!

 

 

 

Window seal strip under the flat bits allows the vacuum to stay where it should

 

The holes in the top of the box get sucked in when the sheet is hot, helps keep it all lined up til it cools too