Mosquito 1/32 from HK... tooling process ?

[JOAN]

Hi,

Sorry if this was posted before but I just had a look at the review here : http://www.largescaleplanes.com/reviews/review.php?rid=1518

...and wondering about the tooling injection process : can anyone explain what is this new process ( one single wing piece and no fuselage halves ! ) and how the injection mould work ?

many thanks for any informations.

Anyway this kit look splendid.

olivier

Edited June 24, 2015 by JOAN

[airfix42]

HK or Tamiya lol or both

[3DStewart]

The tool works by having parts (slides) that move at 90 degrees to the main core and cavity halves. The core and cavity make the outside of the fuselage and the slide makes the inside. The tool opens and the slide slides out of the wide end of the fuselage. Slides can be made to move in all sort of interesting directions. I've seen curved ones moving in arcs and rotating ones that form threaded holes. The slides are usually moved by some sort of cam, but they can be worked by hydraulics or electric motors.

I have to admit I'm puzzled how they've done the wings, but without examining one I'll have to stay puzzled.

Incidentally, Airfix was using slide technology on their 1:32 cars in the late 60s, but its only recently they've become common on aircraft kits.

Edited June 23, 2015 by 3DStewart

[jhutchi]

I have no idea how they are made but I saw one today at DH Museum in London Colney. Beautiful moldings and looks a lovely kit.

Only £149 too!

[Ancient One]

To help anyone who is thinking of buying the Hong Kong 1/32 Mosquito Beware !!! I purchased one Yesterday and took it back today to get my money back, all down the fuselage are lines of slightly raised moulding marks some of which would not be able to be taken off without taking detail with them. This problem also was on the wings to a small extent. I have e-mailed Pocketbond and it will be interesting to see their reply. I certainly would not part with that kind of money for that standard of quality control.

[Julien]

You dont by any chance mean the dope tape which covers the joins in the wooden components do you?

[Mike]

If you mean these little raised bits on the fuselage (I'm looking at a HK fuselage as I type this), they're supposed to be there, as Julien said above - check out our walkaround pic here:

[Ancient One]

No I thought they were there, but on the nose section there are wavy lines. Also the strake which runs back on the Starboard side has a line by it which I cannot see on any references of mine, it just looks like the strake is duplicated, it is the same shape as the the strake.

Edited June 24, 2015 by Ancient One

[Ancient One]

I do not think I have explained myself well enough, the nose section has some wavy lines like the tape covering on the fuselage and I cannot see these in any references of mine. The strake on the starboard side has what looks like another strake displaced below it and slightly to the rear of the strake and is shallower. This being the one I could not erase without taking off the proper strake. Am I wrong? Should there be two strakes there, and should these wavy line be there on the side of the nose

Edited June 24, 2015 by Ancient One

[Shar2]

Do you mean like the shallow longitudinal strake seen here just beneath the main strake?

http://www.britmodeller.com/forums/index.php?/topic/71199-de-havilland-dh98-mosquito/

[Ancient One]

No the strake which is duplicated is on the starboard side of the fuselage at the rear of the trailing edge by a hatch, And the wavey lines are on the side of the fuselage below the cockpit

Edited June 24, 2015 by Ancient One

[Knight_Flyer]

If you're able to post a photo of the duplicated strake it might help us determined if it is a fault or not. You can also send the photo to the retailer to explain your complaint if indeed it is a fault with the model.

[Ancient One]

No I cannot post a picture as I have returned the kit as some other aspects seemed off register as well. But the photo posted of the yellow Mosquito in this topic only shows one strake so unless the Identical shallower second strake on the model, does not show in the photo in the photo of the real aircraft the kit must have been faulty.

[markjames68]

Simplified a lot, The wings are moulded with a 3 part mould, top, bottom and central core.the top and bottom mould close around the core, plastic is injected , cools, and the top and bottom core then move away, the wing is then slid off the central core through the trailing edege( flap / aileron box), the slight flexibility of the plastic enables this.

I bet other companies have a go somewhere down the line but it does strike me as a bit gimmicky and more expense for less parts( am always a lover of high parts counts;)) also just a guess here but pretty close i reckon, it will be important when the moulded wing is pulled off the central core, to early and it will deform badly due to being too soft, too late and it may strain the plastic, quality control COULD be an issue if care isnt taken .

Edited June 24, 2015 by markjames68

[sinnerboy]

for Gods strake...it's only a model!

sorry, couldn't resist

[JOAN]

Simplified a lot, The wings are moulded with a 3 part mould, top, bottom and central core.the top and bottom mould close around the core, plastic is injected , cools, and the top and bottom core then move away, the wing is then slid off the central core through the trailing edege( flap / aileron box), the slight flexibility of the plastic enables this.

I bet other companies have a go somewhere down the line but it does strike me as a bit gimmicky and more expense for less parts( am always a lover of high parts counts;)) also just a guess here but pretty close i reckon, it will be important when the moulded wing is pulled off the central core, to early and it will deform badly due to being too soft, too late and it may strain the plastic, quality control COULD be an issue if care isnt taken .

Thanks for the comments. Amazed about the wing drawer...and the cost of these moulds. I guess no specific plastic adjuvant are added into the PS...(?)

olivier

Edited June 26, 2015 by JOAN

[keith in the uk]

for Gods strake...it's only a model!

sorry, couldn't resist

Nice one , you cracked me up

[Mike]

I do not think I have explained myself well enough, the nose section has some wavy lines like the tape covering on the fuselage and I cannot see these in any references of mine. The strake on the starboard side has what looks like another strake displaced below it and slightly to the rear of the strake and is shallower. This being the one I could not erase without taking off the proper strake. Am I wrong? Should there be two strakes there, and should these wavy line be there on the side of the nose

I can see a wavy line on the nose section of the review sample, but they're just flow lines in the styrene, and don't show up under paint. If you look carefully at my review pics, you can just about make a few out. The "shadow" strake is just more doped tape over the joints. It is again very feint, and on some real airframes that have seen many re-paints, it's probably invisible. As you can see from my review here, I think it's a fine kit, and there's only a few minor niggles to warrant a bit of aftermarket, and that's mainly in the cockpit sidewalls

[wunwinglow]

When I was assistant manager at Beatties in Bristol, I remember having quite an argument with a customer when he brought back an AMT truck kit, where the trailer sides were moulded in silver plastic, and there were flow marks highlighted by the pigment flecks in the plastic. I could not convince him they were not cracks and would vanish under the paint, even predicted any kit in silver plastic would exhibit the same marks, then showed him an Airfix airliner kit (caravelle, I think) and sure enough, when we opened the box, there were the flow lines.

He was determined upon a refund though, so we gave him one. No pleasing some people.

I'm waiting for someone to take back a modern plastic aircraft kit, because the tyres have gone flat.......

Tim

Edited July 2, 2015 by wunwinglow

[sinnerboy]

Incidentally, Airfix was using slide technology on their 1:32 cars in the late 60s, but its only recently they've become common on aircraft kits.

Yep, nothing new in Slide Moulding, where I worked as Toolmaking Apprentice in the early to mid 70's we had slide moulds either operated by cams or devices similar to rack and pinion.

[Ancient One]

Much against my better judgement because Iam so taken with the Mosquito aircraft, I went back and repurchased the kit thinking I could sand out what were actual lumps of plastic on the nose section [ NOT FLOW MARKS] this I have managed to do. But I wonder If someone could advise me about, where the wing meets the front fuselage there are two slots it almost looks like some thing should fit in there yet nothing is mentioned in the instructions,the slots are on the front fuselage section and are noticable from the top view when the wing is offered up to the fuselage. Also two other problems, in the leading edge of the starboard wing is a rectangular indentation it extends to the top and bottem of the wings should this be there? Lastly the strake above the hatch on the rear starboard fuselage has a shape around it representing the same shape as the strake but is not aligned with it. It makes it look as if there are two strakes. I think this is representing a fabric patch, should this be aligned with the strake?

Edited July 2, 2015 by Ancient One

[Shar2]

It would be easier if you could take a photo. Then we can see exactly what you mean.

[Ancient One]

I do not have a camera or phone with camera sorry.

[Mike]

Dave and I have just gone over the relevant parts of the kit on Skype, and there should be five "lumps of plastic" breaking the surface of the nose section, taking the form of two fairings on the side where the wing profile is at its highest, an intake on the port side for the cockpit, and two lozenge shaped lumps with two holes in each just under the side observation windows. Then of course there is the leading edge fairing, which has two tiny slots in that don't appear to be covered by anything - they're portrayed throughout the build, so I wouldn't worry about those.

As to the slight depression in the starboard wing's leading edge, it looks like the tool insert that is supposed to block out a leading edge landing light used on some versions hasn't been fitted totally flush, so there is a tiny difference in the height of the skin. Smear that with a little putty and sand it carefully to the same profile as the surrounding wing, and it's sorted.

[Flankerman]

Yep, nothing new in Slide Moulding, where I worked as Toolmaking Apprentice in the early to mid 70's we had slide moulds either operated by cams or devices similar to rack and pinion.

Back in the early seventies, Gordon Sutcliffe (of Contrail fame) used a 'slide mould' to make the undercut radome on his Tu-95 Bear vacform kit - to save having to make it in two halves.

The radome was the same basic shape as the AEW Gannet/Skyraider/Shackleton - and his moulding box was in two halves, held together with wingnuts.

Fastened together he could 'suck' the vacform plastic into the undercut moulding and then, when the plastic had cooled, he unfastended the wingnuts to reveal a perfectly formed one-piece radome - albeit with a mould seam down the centreline that was easily removed.

Seemples.......

Ken