A pair of Airfix Hawks in 1/72. Finished.

[hendie]

56 minutes ago, Kitsticker said:

BTW a heck of an undercut on the canopy moulds, will they come out of the silicone OK do you think?

 

20 minutes ago, perdu said:

My guess is yes, they will extract from the moulds OK

 

If I can pull armchairs out of my mold as a single piece, those canopies will just fall out.....

 

 

sorry for the thread drift    BTW, these seats do not go Bang !

 

 

 

 

[CedB]

As a molding newbie I hesitate to suggest anything, BUT I did have some success using an electric toothbrush to get bubbles out of my molds if you don't have anything else handy  

[Fritag]

9 hours ago, Kitsticker said:

Gentle warmth, like an airing cupboard, may help...

 

My thought too Geoff; but the slow curing this time has been despite being sat in the airing cupboard.

 

9 hours ago, Kitsticker said:

a vibrating plate will help you. Get a small electric motor and put an eccentric weight on it ( the metal part out of a 'chocolate block' electrical connector is brilliant for this, put the motor shaft in where the wire would go, make sure both screws are tight or they'll get flung off) Then attach said motor to a base plate - I use an offcut of MDF, balsa, whatever is available. Place that on a sheet of foam rubber on your bench, and the mould on the vibrating plate.

 

2 hours ago, CedB said:

I did have some success using an electric toothbrush to get bubbles out of my molds if you don't have anything else handy  

 

Ta chaps.  I might test the theory with Mr F's electric toothbrush and see where that takes me (well it'll take me first and foremost to a telling off of course.......)

 

That said - and fingers crossed - I've not yet had an RTV mould be unusable as a result of air bubbles.  I've had my share of resin casts prove unusable as a result of air bubbles in the resin but that's another matter - and it only take a few minutes to have another go (working in 1/72 scale does at least mean that you're not wasting much resin!).  Thinks:  does vibration help remove bubbles from the resin as well?  You don't get much working time of course...

 

8 hours ago, perdu said:

I read in the Tools and stuff section (at the back of the website, just past the cafeteria) that using the compressor inlet as a vac source should help degas quite nicely

 

I intend giving it a go with my fridge motor compressor next time I do some moulding, might be worth a punt next time for you too Steve

 

Tell you what Bill.  You do a step by step next time you do some casting and if when it's a success I'll shamelessly copy 

 

9 hours ago, Kitsticker said:

BTW a heck of an undercut on the canopy moulds, will they come out of the silicone OK do you think?

 

Yeah.  Not anticipating any problems. The bog standard RTV silicon I use is very flexible when cured and as Bill and hendie say I'm sure these will pop out no problem at all.  After all if hendie can get those seats out ok!

 

Actually that's one reason I make the RTV mould quite thin walled.  There are 3 reasons.  (1) it helps to be able to bend the mould to pop the master/cast out (2) It helps to squeeze/manipulate the mould to encourage air bubbles in the resin out and (3) it reduce the quantity of RTV needed (cheap - moi?).

 

8 hours ago, perdu said:

If Steve intends a vac or pull mould from these masters (he does I think) he needs a decent undercut to give definition to the moulded bits

 

Exactement.  The undercut is actually as small as I could make it using plasticine as the base - and no more than 1 mm at any point.  But as Bill says the plan is that it'll give definition at the edges of the vac pulled canopy.

 

What I've done (you can see it in the piccies) is add some 0.5mm plastic card to the front and rear edges and base of the canopy thereby making the canopy oversize by 0.5mm at each edge.

 

I do this whenever I can on vac masters as I find it helps me to get a clean edge on the vac form later.

 

What I'll do is once I've cut the vac formed canopy from its sheet is to pop it back onto the master and sand the edges to size on a flat piece of glass paper.

 

It's a bu**er to try and sand the edges neatly on a thin vac form unless it's supported in this way.

 

The 0.5mm extra size gives me that extra margin to play with in sanding all the edges flat and neat.  As I sand the edges flat It'll also remove the 0.5mm card add-ons and everything will end up (hopefully) nice and neat and the correct size.  Simples.....(?)

 

8 hours ago, hendie said:

sorry for the thread drift    BTW, these seats do not go Bang !

 

It aint the drift (nice seats by the way) it's the consequences.  Now I'm gonna find myself addicted to a railway carriage build as well!!!!!

Edited April 28, 2017 by Fritag

[Ex-FAAWAFU]

On 25/04/2017 at 9:44 AM, keefr22 said:

 

...FRADU (If that's who they still are?)...

 

736 NAS nowadays.  [The jets leased from the Crab Force.  Ah, the wonders of modern military accounting!]

 

I have yet to succumb to the temptations of resin casting, but I know where I'll be coming for tips if when I do.

[keefr22]

Thanks Crisp. I thought they'd been retitled as a NAS but memory failed me yet again!

 

Keith

[Ex-FAAWAFU]

736 was the squadron that used to do the role before FRADU, if you see what I mean.  

[Old Viper Tester]

As for "stripey" RBF flags, Airwaves used to make a sheet that had both stripes and REMOVE BEFORE FLIGHT formats. Looks like the Aviation Megastore still carries them:

 

https://www.aviationmegastore.com/remove-before-flight-flags-usaf--raf-sc72105-airwaves-sc72105-aircraft-modelling-accessories/product/?action=prodinfo&art=27228

 

Sven

Old Viper Tester

Edited April 28, 2017 by Old Viper Tester
added link

[Giorgio N]

I forgot to check this thread for a couple of weeks and I see a lot more great modelling on display !

 

Speaking of resins and RTV, if the stuff is not curing it's likely because it's too old. Guess how I know... However silicone rubber generally lasts quite a lot, contrary to resin (which reminds me I'd better start making more resin parts before my supply becomes useless...), maybe it's really just a matter of wrong proportions. Low temperatures don't help curing either

 

Interesting to hear of the yellowing of the vacformed parts after using resin moulds, what material are you using to vacform ? I've only done a couple tests with resin masters but never had problems. Maybe I've just been lucky ?

Using plaster: I agree with the use of dental plaster, plaster of paris generally is not smooth enough to get the best results. Not that it can't be used, it can but a smoother master is always best. In the past I had access to some resin used to make dentures, it was brilliant as the finish was very smooth. I originally also used it to cast parts but it was really too hard for our needs as filing or drilling was almost impossible. To make masters for vacforms however it was perfect.

[Fritag]

On 28/04/2017 at 4:18 PM, Giorgio N said:

Interesting to hear of the yellowing of the vacformed parts after using resin moulds, what material are you using to vacform ? I've only done a couple tests with resin masters but never had problems. Maybe I've just been lucky ?

 

It was Vivak PETG Giorgio - which is pretty standard stuff isn't it?  I've got several sheets of the stuff so I'll see how I get on this time.

 

Been a busy week at work cos I'm off walking in Scotland for a week as from tomorrow. 

 

And I didn't get anything much done over the bank holiday cos it was the tour de Yorkshire; the route of which went about a mile and half from our door 

 

Anyways.  The RTV eventually cured so I heaver some resin casts to see if I can get some decent clear vac formed canopies from:

 

 

And I managed a little more of the detailed painting on the seats:

 

 

Looks a bit stark at the mo' and rather ordinary.  But hopefully they'll tone down a bit with some dry brushing and washes - and most of this will be covered by the back rest and harnesses - I'll see if I can't make them look a bit more impressive.

 

 

 

 

 

 

[giemme]

Good to know the moulds cured, Steve 

 

I like those seats already, a few more touches and they'll look the bee's knees

 

Enjoy Scotland!

 

Ciao

[perdu]

I have stopped using PETg since having lots of those "amazinglyappearingbubbles" episodes so now I get acetate sheet (0.6mm I think) from my local art supplier who sell me a sheet of it in A1 size and guillotine it nicely to A4 when I asks 'em to

 

Seats?

Steve what can we mere morts say about those pieces of subliminity, they are lovely.

 

So lovely I wish I had a few to play at modeller with...

 

 

 

Oh wow, guess what I just found courtesy of our friend in Cheshire...

 

 

As to looking a bit ordinary, I have two iterations of Airfix Hawk

 

Yours do not look ordinary by any means

 

Enjoy your self punishment routine, walking, hmmmphh

 

Done that, got the new knees

[Martian]

The seats are coming on well Steve. Once the harnesses are on they will busy up the seats quite a lot.

 

Martian

[xffw45343tg]

I'm sure Mk.10 seats have quite visible rivets on the sides of the seat pan...

 

[Cookenbacher]

Wonderful stuff Steve, but I'm still getting over the dropped flaps from a few pages back - perfectly executed. Everything since then has been a blur.

[Fritag]

On 05/05/2017 at 0:56 AM, perdu said:

 

I have stopped using PETg since having lots of those "amazinglyappearingbubbles" episodes so now I get acetate sheet (0.6mm I think) from my local art supplier who sell me a sheet of it in A1 size and guillotine it nicely to A4 when I asks 'em to

 

 

I've still got several sheets left from my last purchase Bil, so I'll see how I get on.

 

On 05/05/2017 at 3:05 PM, Kirk said:

I'm sure Mk.10 seats have quite visible rivets on the sides of the seat pan...

 

Your'e a bad man Kirk.   Although I s'pose I could post em to Crispin; what's a few more rivets whilst he's at it......

 

On 05/05/2017 at 5:44 PM, Cookenbacher said:

i'm still getting over the dropped flaps from a few pages back 

 

 

Funny that Cookie, so am I 

 

This is why I keep coming back up to Scotland to go walking:

 

 

But I must confess I'm missing the bench and the Hawks.   I think I might be rediscovering some enthusiasm for em...

[giemme]

36 minutes ago, Fritag said:

This is why I keep coming back up to Scotland to go walking:

Wonderful landscape Steve, I can see why you want to get back there   (albeit I bet it's rather chilly - can you believe that in Sicily today we had 30°C?  )

 

Few more days and you'll be back to the bench ...  

 

Ciao

[Fritag]

Well - I'm back - altho' with walking in places like this to be had in the North of Scotland it was tempting to stay......

 

 

And I've been working on the bang seats.

 

I've more or less finished the detailed painting using a mixture of humbrol metalcote, humbrol enamel black, mr hobby olive green, some thin slivers of red decal and a red pen.  Oh - and dry brushed the black on the head boxes to tone it down a bit and emphasise the round indent. They're a bit shiny at the mo, cos they've had a protective coat of Klear.

 

 

I've also worked on reproducing the rear seat solo flight aprons.

 

The obvious choice of material was wine bottle foil - stored away in the days when even the sub-£10 a bottle wine the Fritag's habitually imbibe came with corks and foil.....

 

And to shape the apron I cut down a spare resin cast of the seat to act as a mould:

 

 

Suitably sized strip of foil on the mould:

 

 

And then burnished down and trimmed.  Here's one on the mould that's just about finished and 'tother dry fitted to one of the seats.  Looks ok.

 

 

More foil work to make the seat/parachute back pad for the front seats:

 

 

  And dry fitted for a look-see:

 

 

The foil work is now set to one side, safely locked inside a couple of little jars waiting for priming and painting.

 

Next up was a black oil wash to try and make the detail pop out a little and take away some of the toy like look.  Sploshed some on and let it dry.

 

 

And then started removing it with a brush moistened in Winsor & Newton Sansodor (it's low odour and not too aggressive solvent).

 

A before and after shot....well p'raps not quite after - I think I need to take a bit more of the oil wash off as it looks a bit dirty/messy:

 

 

And the first one looks like this at the mo:

 

 

 

 

Getting there.

 

Should look a bit busier when the foil back pad plus the painted PE straps I'm (hopefully) going to use are applied.

 

 

 

 

 

 

 

[hendie]

I miss the old country when you show photo's like that.... then I remember the weather...

 

 

them bang seats sure are bangin'

[Brandy]

Beautiful work on the seats, and the walking looks really good too! 

 

Ian

[CedB]

Beautiful work Steve, looking very realistic  

[perdu]

Walking?

 

I'm sure I remember walking someplace

 

 

Some times...

 

I love retirement, now I don't have to...   😈 

 

The seats?

 

Definite WIN painted all over those beauties Steve, they're marvels

 

 

 

Oh yes, nice to have you back

 

 

 

 

 

🎺🎺🎺🎺🎺🎺🎺

 

Copland plays….......…

Edited May 16, 2017 by perdu

[Biggles87]

I have to keep reminding myself that this is all in 1/72!

[TheBaron]

Those seats look [groan] bang-on - some lovely subtleties of shape emerging from that treatment. You can never have enough wine bottle foil can you?

 

Splendid landscape shots too. I've fond memories of Skye and  Iona...

 

Tony

[giemme]

Those bang seats are marvelous multimedia kit in themselves!

 

I think the oil wash is spot on, looking at your last two pics. Can't beat wine bottle foil for that kind of detailing, can you? Have you considered using it for the harnesses as well, or is it a too complicated of a bundle?

 

Ciao

[Leonl]

As they've said... Those seat are looking very good...