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You may get away with that and if you need to simply add a layer at the weak points if any

 

Its all an experimental game anyway

 

👅

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1 hour ago, TheBaron said:

can you laminate this gear I wonder by sticking two sheets together?

 

you can, but you'll probably end up with sink marks caused by the glue, unless you spread it really thin. 

I would still start off with 1mm thick styrene - you can always go thicker if it doesn't work. Going thicker may be more difficult to heat evenly unless you use the oven.

The worst areas are going to be the vertical sections as they get stretched further than anything in the horizontal plane, obviously.  That will make your attachment surfaces to (what little is left of the) kit, very thin. However, you can add formers in that region to beef up the bonding area.

Leaving the buck a bit oversize has it's benefits in this case. If it's too long - you can easily trim off the excess, and if it's too wide - provided you get the curves you want, you can cut a slice out of the middle and join the two parts fairly easily

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1 hour ago, perdu said:

You may get away with that and if you need to simply add a layer at the weak points if any

 

Its all an experimental game anyway

 

44 minutes ago, hendie said:

 

you can, but you'll probably end up with sink marks caused by the glue, unless you spread it really thin. 

I would still start off with 1mm thick styrene - you can always go thicker if it doesn't work. Going thicker may be more difficult to heat evenly unless you use the oven.

The worst areas are going to be the vertical sections as they get stretched further than anything in the horizontal plane, obviously.  That will make your attachment surfaces to (what little is left of the) kit, very thin. However, you can add formers in that region to beef up the bonding area.

Leaving the buck a bit oversize has it's benefits in this case. If it's too long - you can easily trim off the excess, and if it's too wide - provided you get the curves you want, you can cut a slice out of the middle and join the two parts fairly easily

Bill & Hendie: Thanks for the feedback lads, I'll take those points on board. Either way this part of the job looks like it will be experimentation-city!

 

I got the buck roughed-out in the shed using the the jigsaw and belt-sander just now:

34308045983_a28cbc7c38_c.jpg

I'd be quite surprised if any of the first attempts turn out to be acceptable but tbh I'm just approaching the whole process as a 'learning-to-vacform' exercise, warts n'all. It might have been easier if I wasn't trying to do it in full view of everyone of course (:phew:), and  although it will probably work out painful to watch for more experienced hands, hopefully it might encourage others to try this route for themselves if they can see what's involved.

 

Looking through your excellent Sherpa build earlier I see what you meant about using drawing pins to keep the plastic in place when heating Bill, so I shall be nicking adapting that methodology I think later on.:thumbsup2:

 

I'm not sure how much progress we'll make over the rest of the week as things at work will be pretty up in the air which usually translates into coming home with limited patience left over. A little bit of therapeutic filing here and there mightn't be the worst antidote in the world to such matters!

:bye:

Tony

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I

3 hours ago, TheBaron said:

 

Dennis, Martian  & Bill: Thanks for that all. :D

 

As this is all new to me I had left the buck a few mill. proud compared to the kit out of caution: birrovabugga about the thickness issue though as I'd ordered a sheaf of 1mm stuff at the weekend - can you laminate this gear I wonder by sticking two sheets together?:hmmm:

 

 

I suspect it would delaminate immediately you put heat on it. Try a pull or two with the stuff you have got. It occurs to me that when you have cut the parts in half, the bits that form the end of the fuselage can be brought up to the thickness of the kit plastic by adding laminations to the inside of the vacform parts and blending in the corners with Miliput. The thinness of the moulding on the door sections will of course, be a plus point.

 

If all else fails and you have to go up a thickness of card, the 40 'thou stuff is pretty useful to have around anyway. I use it a lot for floors and bulkheads as it ads a lot of strength to a model. The Roc floatplane is about to receive a large infusion of the stuff for example.

 

Martian

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Tony, don't forget (and I'm sure you haven't) for your buck design that you have the length dimensions in that Italeri info sheet.

 

Love watching all this engineering, I must confess that these days I'm mainly in the camp CedB mentioned, ie having to buy things rather than all this marvellous making stuff up in sheds, which I admire.

 

 

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16 hours ago, TheBaron said:

It might have been easier if I wasn't trying to do it in full view of everyone of course

 

... but not as much fun for us !

 

16 hours ago, Martian Hale said:

I suspect it would delaminate immediately you put heat on it.

 

It probably would - but that prompted me to remember something.... if I ever tried to vacuum form over a styrene buck, it was a real booger to get the second layer off - the vacuum and the heat had formed a very good mechanical (though not molecular) bond between them.  So... if the vac-form is too small, there's nothing to prevent vac-forming another layer over it to increase thickness.  Just don't try and peel them apart - just add a little thin glue along the edges and you should be good to go.  It's worth a try if it comes to that.

Edited by hendie

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On 2017-6-5 at 7:16 PM, Martian Hale said:

I suspect it would delaminate immediately you put heat on it. Try a pull or two with the stuff you have got. 

Cheers Martian. :thumbsup2:

 

This whole process will be a big experiment of course, but  I reckon if I can treat this as a round from The Generation Game and keep my sense of humour then that will go a long way to keeping anxiety at bay.

 

Out with the old, in with the new:

bruce-forsyth-generation-game-2.jpg

 

On 2017-6-5 at 8:46 PM, 71chally said:

Tony, don't forget (and I'm sure you haven't) for your buck design that you have the length dimensions in that Italeri info sheet.

 

Love watching all this engineering, I must confess that these days I'm mainly in the camp CedB mentioned, ie having to buy things rather than all this marvellous making stuff up in sheds, which I admire.

 

 

My thanks for that  nudge James. I'm presuming you noticed this section in the Italeri guide:

2017-06-06_07-20-52

 

Oh that I had read it more closely several weeks ago!:banghead:

20 hours ago, hendie said:

It probably would - but that prompted me to remember something.... if I ever tried to vacuum form over a styrene buck, it was a real booger to get the second layer off - the vacuum and the heat had formed a very good mechanical (though not molecular) bond between them.  So... if the vac-form is too small, there's nothing to prevent vac-forming another layer over it to increase thickness.  Just don't try and peel them apart - just add a little thin glue along the edges and you should be good to go.  It's worth a try if it comes to that.

That molecular/mechanical distinction is excellent advice hendie and it certainly can't hurt to see how much the process can/be pushed in such a direction.:thumbsup2:

 

Expect a test or two when we get to that stage with the buck! 

 

I'd hoped to have got a little done this evening, but after the day that was in it I'm just too frazzled for any patient work; as it is I'm going to hunker down and carry on with Mark Mazower's concise and illuminating:

 3421688.jpg

One of his previous works:

 9780713991598.gif

...was excellent, and the former tome  provides a startling  perspective in relation to some of the people and ideas subsequently involved in the postwar formation of the EU.

 

:bye:

Tony

 

Update: Just as I was cleaning my teeth I glanced out of the bathroom window to see this going on:

2017-06-06_09-06-27

Felt like a scene from Terrence Malick's The Tree of Life...the mundane and the transcendent in proximity.

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Evenin' all.

 

After the hiatus of getting the vacformer sorted it's back on to first steps on shaping the buck tonight:

35118310066_aac0456376_c.jpg

I'm going to take this part of the build slowly and surely, largely because - as with all subtractive processes - it is all too easy to lose concentration and take off too much. I figured therefore that  it was better to start on the port side and get that approximately right, before moving over to work on the opposite side of the tail.

 

Incidentally,  you can probably make out in the photo above a running repair I had to do to the starboard 'beak' of the BT, due entirely to one of the above-mentioned lapses of concentration whilst roughing out the form on the belt sander. This resulted in about a mill. too much being turned to dust:

35118309796_21085f572d_c.jpg

That's it now with a shard of scrap balsa blended in along the side, and with a bit more to fill along the underside seam you see there.

 

Initially I'm concentrating on getting the junction with the upper wing spar region:

34771810560_0ef03a544a_c.jpg

It still needs to lose some of the convex 'toucan' look across the top, but the port corner is about right:

35118309156_22f8f44789_c.jpg

The main discipline I need to keep myself to here is to alternate checking the buck not only against the fit to the kit, but against reference photos equally, in order to keep the entire form in mind, rather than just the small area you happen to be working on.

 

I made a start also on the lower port corner as well before knocking off for the night:

35118309476_844586909b_c.jpg

More yet to do on that region also.

 

As of tonight then, we're at this point then:

35118308876_802c036e65_c.jpg

Oi reckons nice and easy does it over the next few days on this to avoid any drama. 

 

I'm off now to dribble some glue and sawdust paste into that seam above and let that go off overnight.

:bye:

Tony

 

 

 

 

 

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20 minutes ago, TheBaron said:

I'm off now to dribble some glue and sawdust paste

What on Earth have you been eating????

 

Martian

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Hmm don't ask huh...

 

Carving seems to be your thing Tony, nicely nicely done

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1 hour ago, Martian Hale said:

What on Earth have you been eating???

Glue and sawdust. Immodium for modellers...:o

1 hour ago, perdu said:

Carving seems to be your thing Tony, nicely nicely done

Thanks Bill, but it has to be said that without your sage advice on choice of file, the buck would in all likelihood be resembling a very depressed scone by now.

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Lovely work there, brave choice using Balsa, I could never carve and shape it particularly well.

Edited by 71chally

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Nice and easy does it... every time 🎶

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7 minutes ago, CedB said:

Nice and easy does it... every time 🎶

Inspirational work Tony!

 Who said there are No more heroes any more!

 

Ian

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15 minutes ago, limeypilot said:

Inspirational work Tony!

 Who said there are No more heroes any more!

 

Ian

Wasn't that the strange little girl?

 

Phil

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What a beautiful sunset :).

 

The BT is looking good. That does look a difficult task; and this is only for the former :o!

 

Slowly, slowly  catch the monkey.....

 

Best regards

TonyT

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The mould for the beaver tail is probably the hardest part of the build but I have no doubt that Tony will get there.

 

Martian the Confident

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20 hours ago, 71chally said:

Lovely work there, brave choice using Balsa, I could never carve and shape it particularly well.

Practice, practice, practice:

giphy.gif

16 hours ago, CedB said:

Nice and easy does it... every time 🎶

That tune has been picking at me until I realised it was in an old episode of the Sweeney in which Patrick Mower plays an antipodean lag. Funny the things you remember!:bell:

16 hours ago, limeypilot said:

Who said there are No more heroes any more!

My children. After I single handedly ate one of these over three days at Christmas 2016:

51pFtGo3+bL.jpg

15 hours ago, Phil Lewis said:

Wasn't that the strange little girl?

 

'(Get A) Grip (On Yourself)' Phil.:lol:

5 hours ago, TonyTiger66 said:

Slowly, slowly  catch the monkey.....

You don't mean:

57ed08944c7eae1640bb07cd1cdfb4f2.jpg

A Slow Loris? :rainbow:

2 hours ago, Martian Hale said:

The mould for the beaver tail is probably the hardest part of the build but I have no doubt that Tony will get there.

Three shakes of the Baroness' perfumed hankie to you dear man!:)

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Just a single item for you this evening.

 

I've spent some time going over the reference photos I have of the rear region currently under construction and noticed that the profile of the rear fusalge - BT is not as simple as it first appears. 

 

I've gone round all of my 'J' references and cropped out the required region from various angles to make this point more evident:

35015069962_2c742a6933_z.jpg

Hopefully can see from these shots that the curve of the fuselage is continued down to the junction with the BT, whereupon it then flares out slightly before proceeding to the apex of the BT in an increasingly acute arc.

 

Thankfully I caught this before carrying out any further shaping as it is a detail not readily apparent in many photos - largely as a result of this being a twin-boom aircraft masking the relevant (i.e. most obvious) areas from view from the side.

 

Interestingly enough, it was looking at some shots that @71chally alerted me to previously of an Italian 'J' with the wings and booms removed (that you can see above lower right) that first drew my attention to this issue; typical views from a ground level don't always provide the most advantageous viewing angle to make this aspect clear enough.

 

:bye:

Tony

 

 

 

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Good pictures Tony.

 

This has me wondering; could these complex contours be there to assist in lessening drag, when the aircraft is in flight with the doors open?

 

Just a ponder :hmmm: 

 

Best regards 

TonyT

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2 minutes ago, TonyTiger66 said:

Good pictures Tony.

 

This has me wondering; could these complex contours be there to assist in lessening drag, when the aircraft is in flight with the doors open?

 

Just a ponder :hmmm: 

There must be something to that point Tony as I know that when these aircraft were flown with no rear doors attached, the airpseed was lowered by drag, whereas performance went up again with them added. I can't help thinking that performance dropped off again during recovery when the door frame was tilted up into the slipstream however...

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I expect drag would be better controlled by the BT than opened clam shells, even when it's opened up

 

 

They couldn't open sideways doors in flight, madness, look how they stopped Buccaneers in flight

 

Opened BT doors might even provide some nice drag reduction when raised up as they zooms along

 

Funny stuff airflow

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Oh noo, again.

I actually did some paint.net drawings showing that it isn't a continuous curve across the top going into the tail.

I can try and post them tomorrow, but guessing a bit late now?

Despite being cut off, the Italeri drawing seems to illustrate this as well.

 

One of your early pics seems to show your buck with that double curvature effect, is that lost now?

 

Edit, here they are.  the orange and red lines show the actual curves, the black line a projected continuous line.

35184176525_4953297f3d_c.jpgzz C-119Jp by James Thomas, on Flickr

 

34339493134_55446399e5_c.jpgzzp by James Thomas, on Flickr

 

BTW, paint.net is very good for checking out shapes and curves, as it uses a maths formula for drawing curves.

 

The beaver tail looks a particularly drag reduced way of opening the rear, if you look at pictures it is arranged so that the top line of the BT never goes higher up into the airflow than the top hinge line, ie the bit that slopes down becomes horizontal-ish and no further, which is probably why the inwards opening door is so important, if that makes sense?!

 

Absolutely just in case, you know that the BT tail is almost 5' longer than the standard arrangement.

 

On 06/06/2017 at 7:35 PM, TheBaron said:

2017-06-06_07-20-52

 

You've certainly gone brave with this one Tony, there's always that resin set!

 

 

 

 

2nd edit,

Remember I mentioned that I have seen an attempt of a C-119J online, here it be,

C-119J WIP 01

 

On balance, you are doing well!

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16 minutes ago, 71chally said:

On balance, you are doing well!

 

 

On Balance !! :o  I would say he is far in advance of that other build, way in advance of it in fact!! :thumbsup:

 

Gondor

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2 hours ago, perdu said:

I expect drag would be better controlled by the BT than opened clam shells, even when it's opened up

The nub of the matter. I suspect you've touched upon it, in the light of James' comments below. :thumbsup2:

26 minutes ago, 71chally said:

One of your early pics seems to show your buck with that double curvature effect, is that lost now

No, we should still be good James.

 

I'd stopped last night with some roughing out of shape only so it should be possible to work within that initial curve to incorporate this extra set of contours.

29 minutes ago, 71chally said:

BTW, paint.net is very good for checking out shapes and curves, as it uses a maths formula for drawing curves.

 

Absolutely just in case, you know that the BT tail is almost 5' longer 

That's interesting about paint.net. Thanks. On the BT length I had factored that in at the initial drawing stage; iirc it works out about 1/3 longer than the clamshell variant.

 

I took a look at that 3d printed tail btw. From the image on the page here I'm not sure they've got that profile correct at the tail/fuselage junction:

https://www.shapeways.com/product/QZVKEAPSU/fairchild-c-119j-quot-beaver-tail-quot-cargo-door-in-1-72

 

21 minutes ago, Gondor44 said:

 

On Balance !! :o  I would say he is far in advance of that other build, way in advance of it in fact!! :thumbsup:

Ah Gondor. What a lovely thing to read last thing at night! My thanks sir.

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