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paul fisher

So what about a hybrid Vac/resin kit?

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I did this kit a while back. Do a google search for PP Aeroparts Firefly. Vac formed major parts, loads of resin, etched brass, white metal, decals and so on. Complete labour of love, but we sold enough to make it worthwhile! Pity the rest of the business went belly up. I sold PP Models to Dave Parkins at Flightpath, and I think he modernised the kits to include more resin.

 

1-48-pp-aeroparts-firefly-stbd-front.jpg

 

http://www.britmodeller.com/forums/index.php?/topic/64703-pp-aerokits-firefly-questions/

 

Tim Perry

 

I remember this one well - Awesome kit Tim.

 

Derek

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There may be an issue getting modelers to accept vacs. However, if the vac part of the kit is kept as simple and easy to assemble as possible, I think it should be possible tp make it happen.

For me vac is something that should be dis-invented. Maybe it is because I never had chance to use proper quality vac. But all vac canopy I had to deal with turned into a disaster. Poor quality plastic, not rigid enough, difficult to adjust, difficult to cut to the correct shape.

So I agree with you Bob, as far as it stays simple and easy, it could be a way to lower kits prices.

 

I am confident that with Paul's skills it will turn into something great (as usual).

 

my 2 cents

Edited by discus

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Vacuum formed parts need not be difficult, but you'll need to develop some skills beyond the sawn of and sanded resin part or a bit of light filling.

If that isn't in your life plan, fine. You keep buying fewer, more expensive, shake the box kits, but if, like a lot of people, you really can't justify to your wife/kids/bank manager yet another 150 quid/bucks on what they would regard as an indulgence, then we vac-form kit designers will be doing our best to give you a very good start on the road to a more affordable hobby, which, you might just find, will give you the biggest buzz of satisfaction and pride you ever had from using your own hands to almost create something that nobody else has in exactly that form.

 

I believe and obviously so do others in a position to actually put these things into production, that there is a perfectly approachable and likely increasing, given the chance, market for this angle on model aircraft building. If we are proved wrong, then patterns good enough for QUALITY vac-forms can, with a little modification be used as patterns for expensive resins, so we will not have lost out. Only those on tighter budgets will have done so, so it is up to those members of the hobby to support our attempts.

 

There is, or really could be, room for everyone.

 

Martin

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This is an idea I have been discussing with some, including Derek.

 

At some stage, Paul, you are right, resin is just not possible because of the weight of the molds, and of the parts, when size grows. Now, we can also argue that people like HPH or Anigrand are successful doing so using techniques that exist for 1:1 sailplanes or boats. But it is still a limiting factor, if only for costs of materials and man-hours to cast those ... the price of HPH's Catalina puts this superlative kit outside the grope of 99,9 % of modellers.

 

... So having large parts as vacforms is an definite option, IMHO.

 

This said, as a modeller, I have been dreading the "separate from the sheet then sand" part of the vac-form building process, the other one being the formers/spars which have to be included to give some rigidity to the kit. If these can be done in resin, of precut on a plastic sheet, then we have a better proposal already. Plus of course the detailing bits in resin. Doing details from scratch is fun to me, but I can understand the measuring and test-fitting of these parts can be a chore for most (and I can put myself in this lot as well).

 

An idea to pursue anyway if it allows Paul to release a F3H kit ! (or a Skywarrior :innocent: )

 

Hubert

Edited by MostlyRacers

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This is an idea I have been discussing with some, including Derek.

 

At some stage, Paul, you are right, resin is just not possible because of the weight of the molds, and of the parts, when size grows. Now, we can also argue that people like HPH or Anigrand are successful doing so using techniques that exist for 1:1 sailplanes or boats. But it is still a limiting factor, if only for costs of materials and man-hours to cast those ... the price of HPH's Catalina puts this superlative kit outside the grope of 99,9 % of modellers.

 

... So having large parts as vacforms is an definite option, IMHO.

 

This said, as a modeller, I have been dreading the "separate from the sheet then sand" part of the vac-form building process, the other one being the formers/spars which have to be included to give some rigidity to the kit. If these can be done in resin, of precut on a plastic sheet, then we have a better proposal already. Plus of course the detailing bits in resin. Doing details from scratch is fun to me, but I can understand the measuring and test-fitting of these parts can be a chore for most (and I can put myself in this lot as well).

 

An idea to pursue anyway if it allows Paul to release a F3H kit ! (or a Skywarrior :innocent: )

 

Hubert

 

Looks like I'd better start something then! (Well said Hubert).

 

Derek

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Im always interested in what tips people who work, are working or have worked vacs have to say. Its about the last frontier for me on the modeling front and Id love for my first one to be like yours Dan, and thats a nice project Im not going to get to worked up over or get to complex with.

 

I have a great Idea to implement the above and appy the KISS Theory..................

 

 

 

Following along here again with great interest!!! :popcorn: :D

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What I'd NOT do in vacform is the clear parts. In spite of the fact clear vac parts are more accurate regarding thickness, they sometimes yellow and are a pain to assemble... I hate them and generally prefer the resin approach.

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What I'd NOT do in vacform is the clear parts. In spite of the fact clear vac parts are more accurate regarding thickness, they sometimes yellow and are a pain to assemble... I hate them and generally prefer the resin approach.

 

Hi Thierry,

 

With the very old vacforms where they used thin acetate platic for the clear parts, I would agree with you. However, we have a number of better non-yellowing clear plastic materials these days which can be formed from increased thicknesses, so it should no longer be an issue.

 

Derek

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For sure the old generations of clear thermo-plastics were surely not optimum. However, even if the newest ones have the tendency to avoid yellowing, gluing them is still complicated. Moreover, they stay fragile!

Another aspect, not discussed up to now, is the difficulty to get symmetric resin parts such as half-fuselages. Fisher cleverly avoided the difficulty as the fuselages were either full of split in the other axis. This is far more difficult when the kit becomes very large. Part of the resin kits I own with the classical left-right fuselage parts cut have a small to large length discrepancy and this is a pain to correct. The longer is the kit, this higher is this problem probability.

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Good Morning All..

 

A fascinating thread has developed here!

 

It is all too true that the bigger the model, the more shrinkage and weight of tooling and parts comes into play for the manufacturer as well as the end user. Part of my renewed interest in mixing vacuum formed plastic parts with the high-detail bits done in resin is driven by these factors, as well as the sharp rise in postage costs over the last year.

 

While a hybrid kit will certainly cost less than a full resin kit, the difference will not likely be as great as some might think as the same care and time must go into the masters, but shipping costs will certainly fall. I am not interested in stepping backwards in time to the plain "shape" kits of old...while there are some ( myself included) who enjoy them, I think most of us want more finesse than that.The balancing act would be to provide enough precision of form to make parts preparation fairly easy, and construction likewise.I mentioned the Dynavector kits as I think Taro really did provide excellent kits, and I would aim at a similar outcome, though using resin for the details. I have never in my life seen white metal that would suffice for the sort of cockpit detail we all demand these day and I felt that was the only real shortcoming of the Dynavector kits..

 

The resin stuff is , as Stephen and others have noted, still expensive to master and produce to a high standard and this would still need to be recovered with a reasonable profit over a fairly small number of kits. It may well be that by going to vac-formed air-frames we save more weight than anything else, and it may also be that a large portion of potential buyers will simply avoid them out of distaste for vacs..I don't know. I suppose the only thing is to settle on a proper subject and try it out.

 

I do ramble on and on as the song goes...back to work!

 

Paul

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I think we should give John Adams of Aeroclub, credit here, gents, for having done all this in the past. It isn't anything new, even if it is in larger scales. It's actually a fairly obvious materials choice. I'll stick with w/m detailing as I have trouble finding resin casters who are:- A) in Britain B) reliable and C) not so packed with work they are quoting silly lead times (like CMA Mouldcast). I find vac-forms very easy to make, in fact. I always thought it a pretty sensible way to make a limited run kit at a reasonable price, hence my willingness to put my money where my mouth was with my own range. If, as Brian discovered with his foiled models, atmospherics can cause dimensional instability in resins, especially larger ones, vac-forms are probably the ideal answer, as there is less bulk to move in different temperatures. (You should try replacing 80% of the oak planks in a narrow boat, it moves almost as you look at it!).

Martin

Why can I never type a "B" with a bracket after it, without it looking like a smiley?

Edited by GuildAero

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Just as an add-on, I think the only thing that w/m wouldn't really suit so well would be the longish, thin panels of cockpit interior that resin seems to suit.

As for detail, if I put it on a master, my w/m guy can cast it and surely w/m undercarriage is much preferable for both strength and the ability to scrape and burnish it for oleo legs, for instance.

Obviously a combination of all three is the ultimate, but resin is not currently a possibility for me for the reasons given in the post above. If Paul can do his own, he's on a winner, it seems to me.

If that means that the rest of you won't accept anything else and I have to pack up before I even begin, you guys will have to wait for a lot longer for certain models.

 

Martin

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In short, quality costs, whatever medium, or media, you use!! This is all a matter of balancing what you can do, against the impact on the cost price, and ultimately the price the consumer is prepared to pay. Maybe there is scope for a SimCity kind of PC game, where you can try out all these possibilities, rather than going on a hunch! Might have saved PP Aeroparts, all those many years ago. Maybe....

 

Tim

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Why can I never type a "B" with a bracket after it, without it looking like a smiley?

 

Just going off-topic briefly to answer your question Martin, but this happens because the forum software treats the juxtaposition of those two characters as a shortcut for that particular emoticon, and replaces them. Most of the emoticons have text-based shortcuts; in fact, that's where the idea and term comes from - text-based character combinations used to imply various 'mood' faces. The forum software simply looks for those and replaces them with representational icons. To my knowledge it's only the combination that you used that causes any trouble (I've been caught out by it myself).

 

Kev

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Well now...I seem to have stuck my foot in it here...

 

Martin, of all people on this earth I would be the last to disrespect my friend and mentor John Adams, I hold the man and his work in the highest regard, and one of the high points of my life was getting to meet him face to face at Telford a few years back.For that matter, I would not likely have gone into this business some 35 years ago if not for Gordon Stevens and the wonderful RarePlanes kits or pictures of Peter Cooke's magnificent work that allowed a young model maker to broaden his horizons beyond Me-109s and P-51's back in the '70's.

 

Be that as it may, this is my little corner of LSP, and I don't like white metal for anything much besides the occasional landing gear leg. I use it myself when it fits the situation. That's just my personal opinion, not a slam on anybody. I mean no-one any disrespect, and I certainly don't mean to discourage you from jumping back into the pond with some vac form stuff, so there you go...hopefully I can get one of your Hornet Moths when your ready as I haven't the bravery to kit one up myself and I do very much love the aeroplane ( see there, I even spelled it right ) .

 

Now then..it is Friday afternoon , and I hear a gin & tonic calling to me, so off i go.

 

Paul,

hoping to smooth any ruffled feathers!

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