Can you use vacform kits as moulds?

[McColm]

I sometimes come across a 1/72 vacform model kit that is damaged and in the past I would have replaced the damaged piece with plastic but now that I have had a go at using resin for making parts I'm thinking why not use the vacform kit as a mould?
Is this possible?
I have yet to perfect propellers but an engine could be useful and a redesigned fuselage of the Avro York so the wing section is blanked over could provide a few whiffs.
I know that there's not a great deal of detail with these kits but if multiple models are required it's a good starting point.

[NARSES2]

One issue would be in ensuring you can remove the resin from your "mould" once it sets. Others will know more about the possible chemical reactions between the plastic of your "mould" and the resin you are using.

Another would be that "castings" would be slightly undersize if it's accuracy your after.

[McColm]

One issue would be in ensuring you can remove the resin from your "mould" once it sets. Others will know more about the possible chemical reactions between the plastic of your "mould" and the resin you are using.

Another would be that "castings" would be slightly undersize if it's accuracy your after.

I've been using silicon spray before pouring in the resin. This seems to work, I don't go for accuracy but if the vacform part was reversed and a resin mould cast that would work.

[NARSES2]

If it works for you   

[PR19_Kit]

There was one  particular 'company' that did the exact opposite.................

The Welsh Models original 1/144 scale Boeing 757-200 kit had vacform wings and fuselage, but Densil Wade,  who runs the firm, made a mistake with the shape of the fin, but the kit went into production anyway as it was easy for the  builders to fix.

At one Telford show in the 90s I found an injection kit of the 757-200 with the  EXACT same mistake on the fin, and I took one over to show Densil. The injection fuselage/fin moulding fitted precisely inside one of Densil's vacform fuselages! The ratbags had just stolen his modelled shapes exactly.

[kerick]

One issue would be in ensuring you can remove the resin from your "mould" once it sets. Others will know more about the possible chemical reactions between the plastic of your "mould" and the resin you are using.

Another would be that "castings" would be slightly undersize if it's accuracy your after.

I've been using silicon spray before pouring in the resin. This seems to work, I don't go for accuracy but if the vacform part was reversed and a resin mould cast that would work.

The vac form part may twist or bend while you are working with it so make sure it's on a firm surface while casting.
Do you have project in mind for this?

[McColm]

One issue would be in ensuring you can remove the resin from your "mould" once it sets. Others will know more about the possible chemical reactions between the plastic of your "mould" and the resin you are using.

Another would be that "castings" would be slightly undersize if it's accuracy your after.

I've been using silicon spray before pouring in the resin. This seems to work, I don't go for accuracy but if the vacform part was reversed and a resin mould cast that would work.

The vac form part may twist or bend while you are working with it so make sure it's on a firm surface while casting.
Do you have project in mind for this?

I've always had a problem with the Avro Lincoln B.2 bomber when it comes to the fuselage. I have tried using the Flightpath conversion set and try as I might the Blackbird kit is always not available or I don't have enough funds to pay for it.
The Flightpath parts don't fit even when I follow the instructions and cut in the recommended places, apart from the engines they seem to fit. Then there's the wing, I change that to the Avro Shackleton wings whereas if I had a complete fuselage I can convert it into the freighter,  extend the nose for the MR and reposition the cockpit so the fuselage looks even longer. This would mean that there's no cockpit detailing a hardship that I can live with.
Engines, I still have the idea to create the T56 turboprop that can fit onto a radial aircraft on a larger scale to those produced by Alleycat for the Dakota Turboprops.