Scary Skeeter - Aeroclub 1/72

[Harley John]

Page 5! Dammit Page 6! And I'm down by the potting shed, could someone turn up the volume on the garden speakers please! Great stuff Ced, highly stochastic!

Edited February 9, 2020 by Harley John

[CedB]

3 hours ago, limeypilot said:

I agree with Bill about the balls being used to reduce the depth of the vacuum chamber. Still not sure about the radio bit though..

 "flop it over the top of the part and hit the 'suck' button." sigh... if only it were that easy......

 

Ian

Thanks Ian - some illumination below!  

3 hours ago, Biggles87 said:

Throw your balls in the air, said the jugglers. 

All together now.🎵

 

 

2 hours ago, perdu said:

Ouch 😨😕😠😡😩😬😦😧😥😕😣😰😩

Thanks John and Bill  Those emoticons tell a story!

2 hours ago, hendie said:

Ced, 

if I may interject... Bill's astuteness and translation skills are on a par with his modeling skills and he is 100% correct in his statement.

 

However...

 

please don't put your balls in the square recess!  The reason being that under that lies a big sucky thing.  Believe me, you do not want hot plastic sucked over your balls. It's not nice Ced.  It's really not.

It happened to me once (I followed the instructions) and I put my balls in a bag and have never exposed them to the light of day since.

What happens is:  The hot plastic gets sucked down by the scary vicious sucky thing and the softened plastic gets sucked most of the way around each of your exposed balls.

When the plastic cools - your balls won't come out!  Your balls are trapped.

Now you'll have to spend hours prising your balls out of the plastic.

and chasing them if they drop on the floor. 

You can use a knife to try and cut the plastic away but you still have to cut/prise out each one individually.

Try not to scratch your balls too hard as they may rust later though I don't suppose some light ball scratching should be fine 

 

 

Ced - keep your balls safe - you'll thanks me for it later

 

 

As I mentioned above - I put mine in a bag and stuck them in a drawer.

 

Got it, thanks hendie - they will be safely stored  

 

 

A bit of excitement this afternoon.

For those experienced in vac forming I'll post the highlights first:

 

Tiny intake cover thingy in the machine stuck down with BluTak:

 

 

After a few 'experiments' we have a moulding:

 

 

Note where the plastic on the edges got sucked down the hole  

That said, after some fiddling we have a very thin cover with the desired edges (mostly):

 

 

Nice.

 

Looked easy eh? Well…

My first idea was to use a smaller piece of sheet to save waste:

 

 

Trouble is, it didn't heat evenly (held under the heater with tweezers) and didn't want to get sucked down:

 

 

Hmmm.

Perhaps a strip across the frame might work but I wanted to test the machine first so I cut some 0.3mm sheet to the size of the frame and, following the instructions, waited until it was 'under the nether frame', dropped the frame and hit the 'suck' button.

 

Wow, does it suck! (Not in the US meaning of the word)

In a split second I had this:

 

 

And then spent minutes cleaning up the machine:

 

 

 

The plastic gets sucked through the holes:

 

 

… but the manufacturers obviously know that as there are two plates with holes, slightly separated, and the green one in the photo above lifts out - easy (ish).

 

Cleaning up the actual part is tricky, especially opening up the front, but with the fine blades and tiny scissors not too bad if you're careful.

 

Happy with that.

More 0.3 and 0.5mm Plastruct ordered!

[CedB]

23 minutes ago, Harley John said:

Page 5! And I'm down by the potting shed, could someone turn up the volume on the garden speakers please! Great stuff Ced, highly stochastic!

Oops sorry John, missed you over the page  

[Mr T]

Watching this with interest (and not a little amusement) as I have said kit and was thinking about building it for the rotary wingey things GB later this year. Clearly it is going to need to need some work, but I tell myself I am a modeller and I did build the AMP Fairey Ultralight Helicopter which is tiny, but very cute. I have done some plunge moulding in the past, which is less dangerous than messing around with spherical objects. 

[andyf117]

7 hours ago, The Spadgent said:

I have (another) ten years in service gift voucher coming from work in the next few months. Mrs S says I should use it to buy something for me. 😛

I got a £100 one of them, back when I had a proper job - and during those ten years I also got a couple of other vouchers as 'special awards' (one £50, one £75 IIRC)...

....I never got to spend a penny of any of them - OH snagged and/or chose the type of vouchers she wanted, and added to her wardrobe from a certain department store!

3 hours ago, hendie said:

please don't put your balls in the square recess!  The reason being that under that lies a big sucky thing.  Believe me, you do not want hot plastic sucked over your balls. It's not nice Ced.  It's really not.

It happened to me once (I followed the instructions) and I put my balls in a bag and have never exposed them to the light of day since.

What happens is:  The hot plastic gets sucked down by the scary vicious sucky thing and the softened plastic gets sucked most of the way around each of your exposed balls.

When the plastic cools - your balls won't come out!  Your balls are trapped.

Now you'll have to spend hours prising your balls out of the plastic.

and chasing them if they drop on the floor. 

You can use a knife to try and cut the plastic away but you still have to cut/prise out each one individually.

Try not to scratch your balls too hard as they may rust later though I don't suppose some light ball scratching should be fine

I'd have taken the easy way out - chucked them in a foil tray, set light to them, and retrieved the slightly-singed balls after the plastic had all been burned off...

1 hour ago, CedB said:

My first idea was to use a smaller piece of sheet to save waste:

My thoughts exactly; a lot of sheet got used for one small part - I'd follow the same practice as when casting resin or making decals, and produce multiple items in one go...

Edited February 9, 2020 by andyf117

[Brandy]

@hendie please put a warning up next time you post advice like that. I nearly spat my beer all over the barman!

Worse than that, I would then have had to explain why I spat my beer all over him.......

 

Ian

[giemme]

Welcome to the world of vacforming, Ced  As you've already found out, covering all the bottom surface with the plastic sheet is essential: any air leaks would prevent it to being sucked down properly and conform to the template.

 

I'm quite surprised by the vacuum power of that little machine, though!

 

Ciao

[TheBaron]

1 hour ago, giemme said:

I'm quite surprised by the vacuum power of that little machine, though

He's not wrong.

 

Don't think you'll regret that machine Ced - it is one hell of a vacuum in the bottom part so if you find its sucking the plastic down into the holes like that, with that fierce heater you probably don't need the plastic to have been softened quite so much.

 

If you're getting dimples instead of holes, that's probably about the right combination of heat and vacuum. My first few attempts with it I had the plastic so saggy it practically got sucked into a separate universe.

 

In relation to the fierceness of the heating element,  you've got to be cautious when forming transparencies - first couple of goes I just whacked mine up to the top and ended up with loads of bubbles forming. Gently raise the transparency toward the heater instead until it sags just enough to pull a moulding. Usually only half way up was enough and just leave it there until it softens.

 

This device will also make cheese on toast. Yes, I actually did. 🔥 🧀

 

 

[keefr22]

2 hours ago, limeypilot said:

@hendie please put a warning up next time you post advice like that. I nearly spat my beer all over the barman!

 

 

Luckily I was in the house when I did spit coffee all over my screen when I read his advice. Wifey is now looking at me with one of her 'what a pillock' looks....!! 🤣

 

Keith

[CedB]

3 hours ago, Mr T said:

Watching this with interest (and not a little amusement) as I have said kit and was thinking about building it for the rotary wingey things GB later this year. Clearly it is going to need to need some work, but I tell myself I am a modeller and I did build the AMP Fairey Ultralight Helicopter which is tiny, but very cute. I have done some plunge moulding in the past, which is less dangerous than messing around with spherical objects. 

Thanks Mt T  I hope to show any issues...

I have the Ultra Light on my wish list - this one should be good practice!

2 hours ago, andyf117 said:

I got a £100 one of them, back when I had a proper job - and during those ten years I also got a couple of other vouchers as 'special awards' (one £50, one £75 IIRC)...

....I never got to spend a penny of any of them - OH snagged and/or chose the type of vouchers she wanted, and added to her wardrobe from a certain department store!

I'd have taken the easy way out - chucked them in a foil tray, set light to them, and retrieved the slightly-singed balls after the plastic had all been burned off...

My thoughts exactly; a lot of sheet got used for one small part - I'd follow the same practice as when casting resin or making decals, and produce multiple items in one go...

Slightly singed? Nasty  

2 hours ago, limeypilot said:

@hendie please put a warning up next time you post advice like that. I nearly spat my beer all over the barman!

Worse than that, I would then have had to explain why I spat my beer all over him.......

 

Ian

 

1 hour ago, giemme said:

Welcome to the world of vacforming, Ced  As you've already found out, covering all the bottom surface with the plastic sheet is essential: any air leaks would prevent it to being sucked down properly and conform to the template.

 

I'm quite surprised by the vacuum power of that little machine, though!

 

Ciao

Ah, thanks Giorgio  I’ll forget the strip idea then. 

43 minutes ago, TheBaron said:

He's not wrong.

 

Don't think you'll regret that machine Ced - it is one hell of a vacuum in the bottom part so if you find its sucking the plastic down into the holes like that, with that fierce heater you probably don't need the plastic to have been softened quite so much.

 

If you're getting dimples instead of holes, that's probably about the right combination of heat and vacuum. My first few attempts with it I had the plastic so saggy it practically got sucked into a separate universe.

 

In relation to the fierceness of the heating element,  you've got to be cautious when forming transparencies - first couple of goes I just whacked mine up to the top and ended up with loads of bubbles forming. Gently raise the transparency toward the heater instead until it sags just enough to pull a moulding. Usually only half way up was enough and just leave it there until it softens.

 

This device will also make cheese on toast. Yes, I actually did. 🔥 🧀

 

 

Thanks Tony  

It is all your fault, of course. I’ve been looking for an Amazon return with no luck and then I actually needed one!

I’ll watch out for the heater - thanks for the warning. 

16 minutes ago, keefr22 said:

 

Luckily I was in the house when I did spit coffee all over my screen when I read his advice. Wifey is now looking at me with one of her 'what a pillock' looks....!! 🤣

 

Keith

How many of those looks does she have Keith  

[Space Ranger]

11 hours ago, The Spadgent said:

Five times I’ve read that.

Not a clue. 😳😬

It seems to me that perhaps the purpose of the balls is to stabilize the male mold in position while also minimizing the volume of air that needs to be sucked to achieve a satisfactory result.

[giemme]

17 minutes ago, CedB said:

I’ll forget the strip idea then

You could actually reduce the size of the plastic sheet you need to use by fixing it onto a frame with a smaller aperture, wide enough to cover all the holes on the bottom. Cardboard ideally, as it can stand the heat. Hope it makes sense to you, otherwise I'll post a pic of my very rudimentary setup

 

Ciao

[keefr22]

56 minutes ago, CedB said:

How many of those looks does she have Keith  

 

I've lost count...

 

K

[CedB]

57 minutes ago, Space Ranger said:

It seems to me that perhaps the purpose of the balls is to stabilize the male mold in position while also minimizing the volume of air that needs to be sucked to achieve a satisfactory result.

Thanks Michael, makes sense  

52 minutes ago, giemme said:

You could actually reduce the size of the plastic sheet you need to use by fixing it onto a frame with a smaller aperture, wide enough to cover all the holes on the bottom. Cardboard ideally, as it can stand the heat. Hope it makes sense to you, otherwise I'll post a pic of my very rudimentary setup

 

Ciao

Thanks Giorgio - I think I get it but a picture would be helpful when you have time  

14 minutes ago, keefr22 said:

 

I've lost count...

 

K

 

 

 

I've done some more hacking.

 

The foot holes have been drilled - the one on the port side is marked in front of the panel join but should be behind it for this:

 

 

I tried to increase the size of the holes using those broaches but I have no idea how they're supposed to be used.

In and out like a file or round and round like a drill?

Neither seemed to do much to this plastic.

Luckily I have my 0.5mm Hobby Elements file:

 

 

Just about fits. i've lobbed some Mr Dissolved Putty in the kit hole (as hendie rates it!)

 

I've chopped out some plastic to allow for the 'L-shaped' exhaust:

 

 

I'm never sure whether to drill things out at this scale or just paint it black. Thoughts?

 

The inside of the fuselage has a marked square hole:

 

 

I wonder if this is to be chopped out to allow for a 'full frame' undercarriage brace? I'll need to check references (again)

 

The pitot position is marked on the kit so I've drilled it out a bit to remind me to fit some tube later:

 

 

That about does the hacking for the port fuselage half.

On to the starboard!

[Heather Kay]

30 minutes ago, CedB said:

I tried to increase the size of the holes using those broaches but I have no idea how they're supposed to be used.

In and out like a file or round and round like a drill?

Neither seemed to do much to this plastic.

Luckily I have my 0.5mm Hobby Elements file:

You twiddles 'em, dear boy. 
 

To be honest, broaches are probably not the right tool for that particular job. I’d have used drill bits, moving up in diamter to get the right size hole eventually. Another method is the end of a square or triangular needle file gently twiddled in the original hole.

[hendie]

9 hours ago, CedB said:

After a few 'experiments' we have a moulding:

 

 

Note where the plastic on the edges got sucked down the hole  

 

Ced - to prevent the edges of your part getting sucked down the hole,  it's better to raise the buck on something - preferably slightly smaller than the buck.  That allows the plastic to fully form the part, and will then form a slight undercut. That undercut gives you a nice edge to trim to

 

 

[philp]

My thoughts also.  At least everyone I have ever seen do vacuforming has done it that way.

[Space Ranger]

7 minutes ago, philp said:

My thoughts also.  At least everyone I have ever seen do vacuforming has done it that way.

Yep. That technique even works on my antiquated Mattel Vac-u-Form.

[CedB]

11 hours ago, Heather Kay said:

You twiddles 'em, dear boy. 
 

To be honest, broaches are probably not the right tool for that particular job. I’d have used drill bits, moving up in diamter to get the right size hole eventually. Another method is the end of a square or triangular needle file gently twiddled in the original hole.

Thanks Heather - twiddle I will! Are they no good for enlarging holes? If not, then what please, I'm confused  

Sadly I don't have any files small enough - the 0.5mm is my smallest and only just fits; this thing is tiny!

7 hours ago, hendie said:

 

Ced - to prevent the edges of your part getting sucked down the hole,  it's better to raise the buck on something - preferably slightly smaller than the buck.  That allows the plastic to fully form the part, and will then form a slight undercut. That undercut gives you a nice edge to trim to

 

 

Thanks Hendie  

I actually wanted some 'flanges' on the sides - could I use a little block next time, slightly wider than the part?

6 hours ago, philp said:

My thoughts also.  At least everyone I have ever seen do vacuforming has done it that way.

6 hours ago, Space Ranger said:

Yep. That technique even works on my antiquated Mattel Vac-u-Form.

Thanks Phil and Michael  

 

 

I did a bit more last night.

The exhaust is the last bit to go on the port side.

You know all those left over parts we keep just in case they 'come in'?

How about this?

 

 

No, not the spinner, the gate. Actually I used the one on the other side and, after some drilling out and sanding ended up with this:

 

 

Hopefully it will fit over the u/c braces, later.

 

On to the port side. I reckon this Spitfire cannon bump will do:

 

 

May be a little narrow but I've cut the tiny bit out for the step now so it'll do:

 

 

I keep looking at the drive shaft (the white thing).

The General is planning to do an aluminium replacement and some belts - bit too much for me but I'll have a go at something I think.

Later.

[Heather Kay]

6 minutes ago, CedB said:

Thanks Heather - twiddle I will! Are they no good for enlarging holes? If not, then what please, I'm confused

Oh, they’re perfect for enlarging holes, but they’re designed for metalwork really. You may find them easier to use if you fit them in a pin vice, too.

 

Drill bits, plus pin vice, are usual my go-to for opening holes. You can get "micro boxes" with a set that runs from 0.3mm diameter all the way to 1.6mm, with increments of 0.05mm. I drill a pilot hole with a 0.5, then gradually open it up to something bigger using successive bits. 
 

For the day job I have quite the selection of 6in needle files. Again, you can buy reasonably priced sets of these with most shapes and sizes. The round, triangular, square, and half-round ones find most use in my plastic modelling, since they all taper to a point and can be used to carefully open up holes. All but the half-round can also be used as a broach. I generally use the ones with edges by twiddling them anti-clockwise so they don’t bind and cut too quickly into the plastic.

 

Now, I’ve got some eggs, but where did I leave Granny? 

[CedB]

Thanks Heather, useful summary  

 

As you'd expect (??) I do have a selection of drills and files but most of the files are too big for this tiny thing - scary!

I've adopted the 'use drills' tip though - worked great on the exhaust above.

Thanks again!

[CedB]

Not much done this morning - I've been greebie hunting (We're going to catch a big tiny one)

… and hit by a 'tidy bug'.

As far as I know it's not catching

 

Looked for some tube for the starboard exhaust and decided I needed to split my scratch plastic into 'bought' and 'recycled' as there's lots of recycled rubbish.

To do that I needed another bag.

That meant I needed to tidy the bag bag - the bag where I keep my bags.

 

We have Tilly with us while she has her first season (she can't go to day care) and she obviously thought 'Why are you keeping all these bags?'

 

 

She probably has a point.

 

The clear plastic for the canopy has arrived though:

 

 

I probably should find a bag for that - the envelope it came in got wet; we have driving sleet here at the moment, hammering on the skylight. Yuk.

 

Anyway, I'm looking for something for the gearbox and something for the drive shaft.

I started in the box of Spitfire spares:

 

 

This might come in for the starboard exhaust?

 

 

Nope:

 

 

Too short. I'll use some tube.

 

Oooh, what's this in the 1/48 box? Those cartridges might do for the greebie on the side?

 

 

Sanded the back and around the edges, looks OK?

 

 

Looked in the small parts box and found some PE, probably for a wheel hub, that might do for the end of the drive shaft.

I can't believe I didn't take any photos, but the centre was punched out:

 

 

I'll file it to size when it's on the end of the shaft.

 

Lunch now - the hunt will continue!

[Terry1954]

21 hours ago, Harley John said:

Page 5! Dammit Page 6! And I'm down by the potting shed, could someone turn up the volume on the garden speakers please! Great stuff Ced, highly stochastic!

Looks like I almost hit page 7! Can't keep up with you Ced, but agree with all before me, a great subject and a great build so far. Those old Aeroclub models are a great source of enjoyment, and weren't that bad for their time. I have a stalled Gamecock on the go here somewhere. Must get back to that soon.

 

Meanwhile, skeeter on!

 

Terry

[AdrianMF]

Is that PETG clear plastic? It will be interesting to see how you get on with the bubbles (I got plenty!). I've just ordered some 30 thou acetate to give that a whirl.

 

Regards,

Adrian

[perdu]

Ced what are you doing?

 

That curved shield should sit further back, the rear edge begins at the undercarriage strut and at the front is over the pulley spindle

I think you need to relocate it back a tad and a quarter

 

PETg, remember you need to warm it first then give it a reheating to make the workpiece bubble