Vac-forms, these days

[Scratchbuilder]

I tend to do things first...because I want to and second...because I can.

I want to have a go at doing vac-forms, so I will. Who knows what will happen?

I was warned back in the 80s not to bother making model car kits as it was a crowded market. It was indeed, so I decided to knock their socks off with the quality. That I did and received the only 5 star review ever at that point achieved by a British model car company. Being described as the British Bosica was like being compared with Wingnut Wheels in aircraft terms. I sold over 300 BUILT XJ13 Jaguars and hundreds of kits, proving it was worth the effort.

I don't see me doing that with vac-forms, or their being called the equivalent of Wingnut Wheels, I should say here and now! But I see no reason why my vac-forms shouldn't be accurate and buildable by anyone with the will and some simple tools.

Precut? Haha, can you imagine the tooling costs?

Martin

[skippiebg]

Scratchbuilder, on 05 Feb 2013 - 23:10, said:

There is no reason why the tooling should be any more expensive than for resin

An epoxy resin vacform tool for the "typical" (a-hem...) subject would cost GBP 1000. It will stand a good thousand shots or more. By comparison, a resin tool (various rubbers) costs about the same but produces a dozen shots at best.

Vlamgat9, on 10 Feb 2013 - 10:07, said:

Pre-cut vacforms would be wonderful

Yes - if cut in the same direction (parallel to the backing card) that we would trim the parts. There is one brand of "pre-cut" vacforms that falls very short of this. Their idea of pre-cutting is to leave 1/5 inch of backing card all around each part, so we have to go through all the boring cutting and sanding all the same...

I've looked at pre-cut vacforms and there is a promising method to do it properly using a rotatry planer. The result is a fret that looks like an injection moulded kit. There are certain issues to do with the parts "membraning" and ultra precision cannot be assured. All the same, the result is miles better than your classic vacform.

Scratchbuilder, on 10 Feb 2013 - 11:45, said:

...can you imagine the tooling costs?

The rotary planer wouldn't cost all that much, actually. Clearly, it costs some, and it wears off with use, etc, but then the result is much more attractive.

Edited February 10, 2013 by skippiebg

[skippiebg]

I don't think vacforms ever were that cheap ... I think this is due to the lower volume of production rather than compared to other kits

This is the airliner forum and the basic figures are: injection moulding tool - GBP 20-30K, batches 10,000 a whack, sales 1000 or thereabouts a year; vacform tool GBP 2000, batches of say 500 a whack, sales 10-100 a year or thereabouts. Resins are bloody expensive and sales are accordingly often in the units, not dozens, annually. Also, resin has some pretty intractable health issues, both for makers and users. Proof: a 2006 super-duper airliner kit was made in 10,000 copies and sold out in 2012. A 1988 so-so vacform of a British 1960s twinjet airliner was made in 500 copies and sold out by the mid-Noughties.

Now, if there a manufacturing breakthrough were to happen in vacforms to make them user-friendly and attractive, sales could climb to X times these figures, making injection moulding appear marginal in terms of its added appeal to users. Such break throughs could be pre-cutting and some other tidbits like laser cutting, etc.

However...

The real issue for any manufacturer isn't so much manufacturing technique (injection, vacform, resin) but distribution. Revell has that sawn up and each model/hobby shop will take at least one of each new kit they release or repop. Minicraft made a brave effort but never had their distribution network sorted, so as a result sold times less than Revell. A garage manufacturer like Welsh has trouble even getting specialist retailers like The Airline Hobby Shop picking up their releases and repops, leaving them with just mail order. The internet is making direct marketing a lot easier than it was in snail mail days, but all the same, actually picking up a kit in the shop is miles better than looking at it on a screen and braving credit card fraud to buy it...

Edited February 10, 2013 by skippiebg

[rossm]

I don't build kits fast enough to be a major market but I would buy a 1/72 Dash-7 in any media that came out at less than forty squidlings. What else is missing? The flying boats already mentioned (although I doubt I'd live long enough to finish one) and other 1930s types - the Short Scylla has also been mentioned. The Mew Gull has been kitted many times as the final (smaller) version but not AFAIK in 1/72 in a form to make G-AEXF. It's not too small to vacform, I've built a lovely Waku Yak-17 and the outer wings would be a good starting point for cutting down to make wings for G-AEXF. John Aeros Comper Swift is one I'd love to see available again.

I think I'll have to sell the stash and start a buy one, build one regime - then I would be more likely to start a vacform but now my hand wanders past them and lands on the supposedly easier IM or resin before I remember it's not the building of any of them that's the problem, it's the painting I always screw up.

Edited February 10, 2013 by rossm

[Scratchbuilder]

Skippiebg,

I have no idea where you get your costings from!! I wouldn't go near any kit work if the tooling cost even a fraction of £1000! The epoxy tool for a female vac mould would cost about £20 for resin. I make my own. For a resin car body shell, wheel inserts and small bits it costs about £100 maximum, plus maybe £3 a pull and that's a lot of model.

For the Czech guys you get a unit price which includes moulds and resin and is very reasonable, so why you quote such outrageous figures defeats me. I have been in the model kit business since 1970 in one form or another and made over 500 masters for dozens of companies since then. Only the master can cost that sort of money if it's complex, but I make them too, so there is very little cost involved. I wouldn't pay anyone else to do what I can do much better myself. That's why I rebuild my own car engines and do my own decorating, too!

As to marketing, what are forums for? I'm not looking for a big business here. It's a small project between me and my son. If it doesn't work out, so what? I have nothing to prove!

Most small manufacturers can't afford to sell through Hannants and other shops because they want such huge discounts that there's little left for the producer who will never shift that many anyway.

Precut? Why? Can't you handle a knife? It's the work of a few minutes for heaven's sake and part of the pleasure of doing a vac-form.

If you don't like 'em, don't buy 'em!

Martin

[Tripod]

Being a cheapskate, I like my vacforms simple and cheap. The Aeroclub light aircraft were perfect in that respect - white metal for the difficult bits (engine, wheels, prop) and not having to pay for an etched brass and resin interior. The Swift was surely the easiest vacform I've ever built (four times over with different engines).

It was never fashionable to say so, but I liked Contrail kits. They were relatively cheap, and if you had to do some modelling to build them, isn't that what we're supposed to enjoy?

Three-foot Pete

[Scratchbuilder]

Oh well said, Pete. You are my legal victim

No, seriously, you're attitude to vac-forms is exactly what I want to cater for.

If I had my own way, everybody would scratchbuild from absolute scratch and there wouldn't be any kits at all. But then I'd have to go out and work for a living. Tried that.....nah!!

Cheers,

Martin

[Amo Aero]

Good luck with your venture.

Bring out the right subject(s) in the right scale at a decent level of quality and I'll buy.

Edited February 10, 2013 by BOC262

[Iain Ogilvie]

Personally I much prefer a vac kit over resin (maybe a few of the 'twiddly bits' in resin) - providing the basic shapes are accurate - and preferably off a female pattern/mould.

Exhibit 'A' M'Lud - Echelon, Dynavector et al.

Iain

[skippiebg]

Skippiebg,

I have no idea where you get your costings from!!

Well, got quoted that including master, mould and manufacture at a Redhill place in 1992. The geezer was also quoting for making white metal gear at his place after work, using a centrifugal caster. Reckoned that plus inflation... Not any good at mastering or mould making myself... Made a home-made mould at the time. Worked sort of okay, only venting it (making the 000s of little holes for the air to escape, drawing the plastic card into the mould) made me wish I was in the salt mines instead. When I say it worked okay: the mould worked, but I was using a Hoover per a FineScale Modeler article and, well, least said, soonest mended... Getting the plastic card ready was the real challenge.

Edited February 10, 2013 by skippiebg

[Scratchbuilder]

Ah! moulds AND master? OK, that would make sense. The master cost is always going to be the big money. Sorry, I misunderstood.

Yes, drilling all the holes is a pain. I tend to be the Demon of the Broken Drill. I can never get a drill to go where I want. That job is where you need really crap quality bendy Chinese drills that never break, but just go out of shape and can be straightened with a swift wallop with a toffee hammer on the vice jaws! Oh, yes, I'm a pro. alright<G>

My moulds will be females to get some decent detail, but mainly because it means no allowance has to be made for changing material thickness as it would if the plastic were sucked over a male pattern.

Thanks for the warning about the vacuum source. I think my son has an ex Dyson suckmaschine and I was thinking it might be insufficient, so that might be where "the Old Man" does incur some costs!

What I can say, is that my son is a superb photographer and we can look forward to some wonderful shots of kits, as supplied and as finished.

Cheers,

Martin

[John Aero]

Good Quality vacform epoxy/aluminium resin moulds material cost around £30.00 a kilo, anything else will cause problems. A high vacuum pump is essential for sharpness. Drilling holes-no I don't, I have my own method and if I have to drill I don't use twist drills. Use of a female mould does mean material thickness will change, quite markedly so in narrow deep draws. Pre cut vacforms have been the holy grail for a long time, it is very difficult. If a hi speed rotary tool is used then styrene quickly heats and deforms and burrs also the parts need to be held securely and that's not easy (there are ways such as vacuum but vibration of the model shell can release the vac with an instant change of shape the result). If a horizontal band saw is used blade/ material vibration and bounce causes an uneven surface and posible mould damage unless a slave mould is used and that can be problematical.

A vac pulled at start of work will be different in size to one at close of work.

John

Edited February 11, 2013 by John Aero

[skippiebg]

Pre cut vacforms have been the holy grail for a long time, it is very difficult. If a hi speed rotary tool is used then styrene quickly heats and deforms and burrs also the parts need to be held securely and that's not easy (there are ways such as vacuum but vibration of the model shell can release the vac with an instant change of shape the result).

John, imagine a grid of V-section channels acting as sprues. These give stiffness and reduce part "membraning." Also, once trimmed off, your piece looks just like an injection moulded frame. Heat deformation and burring is definitely a problem, as is the life of the rotary tool used, and I have no idea how precise the trimming will be. I reckon a half millimetre up and down (a plinth would have to be provided to take care of that!) would be acceptable to modellers.

Martin, what subj. are you planning? Only, you've posted the topic in airliners, so that got me thinking...

[Scratchbuilder]

skippy,

I am predominantly a civil aircraft fan, hence posting in this section. Research aircraft like the FD2 come into that category to me as they are not military as such and are also rather lovely or at least quirkily interesting. I am an aesthete in these matters.

Number 2 will be a Schneider aircraft, probably the S5. Later, a Short Sealand and a Waco Custom Cabin with floats and ski options.

John, you've just reminded me...I have a load of fine spade drills in a wee pot somewhere!

Martin

[Ed Russell]

Why not? Especially for things you couldn't otherwise obtain.

http://www.britmodeller.com/forums/index.php?/topic/75921-caudron-c445/

http://www.britmodeller.com/forums/index.php?/topic/234916343-supermarine-southampton-comparative-build/

Edited February 13, 2013 by Ed Russell

[Scratchbuilder]

Why not what, Ed? I didn't understand your post.

Lovely builds, btw.

Martin

[Fastcat]

Don't know if you've seen this guy's stuff : http://www.mtaonline.net/~zdk/

They're 1/72 and sell at around $25 or £16

Dave

[Scratchbuilder]

Dave, that's Lars Opland. he's been emailing with a lot of info from Wings of Peace yahoo group. Very nice guy who has taken a lot of time to talk me through his female mould making methods. Lives in deepest Alaska! He does a nice line in 72nd scale Wacos and has sent me a lot of info for a 48th scale one, which is quite a sweet little thing on skis and floats.

Cheers,

Martin

[Ed Russell]

Why not what, Ed? I didn't understand your post.

Sorry - the difficulties of language....

Your original question was

I'm wondering, with the ever increasing prices of specialist kits whether there's still a place for the much cheaper to produce vac-form. Anybody have a hankering for a relatively inexpensive vac-form in the modern world?

so my answer was

"Why not(make some vacforms)?"

[Scratchbuilder]

Ah, right, thanks. It was the distance between posts that fooled me

Why not indeed?

Martin

[Work In Progress]

Dave, that's Lars Opland. he's been emailing with a lot of info from Wings of Peace yahoo group. Very nice guy who has taken a lot of time to talk me through his female mould making methods. Lives in deepest Alaska! He does a nice line in 72nd scale Wacos and has sent me a lot of info for a 48th scale one, which is quite a sweet little thing on skis and floats.

Cheers,

Martin

I don;t know enough about the old Bellancas and so on to have much of an opinion, but his C180/185 is delicious.

[Caerbannog]

Do I understand you correctly Martin - You plan a 1:48 scale vac Supermarine S5? Great!!!

Rene

Edited February 14, 2013 by Caerbannog

[Scratchbuilder]

I do indeed, Rene and have already started the master.

I have a selection of drawings from some highly detailed large scales from R/C Canada to the beautifully crisp rendering in Ralph Pegram's new book. I am also asking Harry Robinson for a copy of his. So it'll be an accurate model.

I'm collecting photos currently.

I intend the models I do to have white metal detail parts, like spinners, props, wheels and separate tyres and as far as research allows, detailed cockpits. No resin as it's just too expensive.

Martin

[Caerbannog]

Excellent! I suppose there will be a note here on BM when it can be ordered?

Rene

[Scratchbuilder]

Oh it will be, Rene, but that is a little way off yet. I have a vac-form back up if my son doesn't get on with it, but I'll be making the patterns and moulds anyway.

Thanks for your interest.

Martin