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[BlueWotsit]

There seem to be so many types of resin around these days, I wonder if anyone can give feedback on which is best suited for which materials and which are definite no no's. This is something that a FAQ for newcomers most certainly could benefit from.

Any tips on using and mixing the various sorts would also be appreciated

I've noticed Fibreglass resins, epoxy resins and polyester resins recently no doubt there are many more.

Im guessing that the fibreglass ones are mainly for use with GRP hulls but what other uses can these have. Epoxies can be mixed with items to use as adhesives and so on.
Polyester resins are a new one to me.

[White Ensign]

The trouble is, that Polyester envolves a gas due to the hardening, which is depending on the included Styrol. These fumes are heavier than air, but stink like hell. Although Polyester-mould has a shrinking-factor of about 7%, as Epoxy only is about 3%. I prefer Epoxy anyway due to the foresaid shrinking-factor and it is not as much as harmfull as Polyester. In both cases a well aired workbench is necessary. Though I do all the jobs with moulds in the garden, wearing rubber-gloves and a protection mask.
Polyester is usually cheaper (not too much), but a small mis-calculation in the mixture could lead to more damages as with Epoxy. Although the reaction-heat at Polyester is much higher as with Epoxy and could destroy the wax-surface on a pattern.
My recommendation is therefor Epoxy, as I found it easier to work with.
Hope this is out of any help.
Jörg

[Subculture]

Glassfibre, or fibreglass resins are polyester or epoxy- the glass cloth is mixed with the resin to form a laminate that makes a very strong and flexible material. The process is the same for either resin used, although the binder used for the glass cloth is different.

Nearly all model hulls made in the UK will use Polyester resin, as opposed to epoxy, Why? Because it's MUCH cheaper (at leaat 1/4 of the price). Epoxy is a better product, but polyester resin gets the job done for most people.

I personally see little benefit in using epoxy resin for conventional scale model hulls. It does have benefits for fast electrics, exotic yachts etc, where the superior qualities lead to a thinner and hence lighter hull.

I find any problems with shrinkage are negligable, but your milaeage may vary depending how fussy you are.

The smell of polyester resin are pungeant (sweet and sickly), however I don't find this a problem, as I have a dedicated workshop. If you are working in the house, then fibreglass resins may cause domestic friction.