EG60 Epoxy Tooling Gelcoat

No, we wouldn’t suggest Epoxy Resins for lining a fuel tank. In general, epoxies have good resistance to petrol and many of the chemicals and additives found within pump fuel however the ethanol in fuel is known to cause problems over time and so specialist tank lining resins (often novalac vinylester based) should be used instead. One such product is GTS 1750 which is sold by Caswell Europe.

No, this epoxy in common with other epoxies does not attack expanded polystyrene

We have not specifically saught FDA (or similar) approval for this resin system so if you were to make these plates commercially then you would either need to make a plate using this resin system and then have it tested and approved safe for food use or use a different resin system that has specifically been approved for food use. Mixed and cured fully and properly the resulting plastic should be stable and non-toxic but testing would be required to prove this. Regarding being dishwasher safe; a dishwasher is a very harsh environment (abrasive, high temperatures, caustic) and so I think it would be quite hard on any resin system. By all means conduct your own tests but I would strongly recommend that a carbon fibre plate was not marketed as 'dishwasher safe'.

Although generally cured epoxies are non-hazardous, none of the products we have are certified food safe and thus we cannot recommend their use with food products.

We recommend Acetone. The brushes must be cleaned before the resin has cured. If you can’t get hold of acetone it’s also possible to use methylated spirits or neat alcohol.

In really simple terms you can think of 1kg of the Epoxy Resin as being 1L. If you want to be really exact (for example if you want to mix the resin and the hardener by volume and not by weight (which we don't recommend because it's unnecessarily complicated) then the relative density of the resin and the hardener, and the mixed product, can be found on the technical datasheet.

We can send any quantity of resin to Portugal. We would use a TNT Road service. To find the shipping cost for any item, simply add it to your basket and then click the 'Estimate Shipping' button on the basket page. The price will then be shown once you chose your shipping country (Portugal).

Unlike other resin systems such as polyester or vinylester, it's very important to get the mix ratios accurate with epoxies. If you get the mix ratio wrong by a small amount (let's say a couple of grams on a small mix) then the resin will still cure but the mechanical properties won't be quite as good as they would have been if the mix ratio had been exactly right. However, if you were to be out by anything more than a few grams then you might find that the resin would not be properly hard when cured and/or may have a tackiness to the finish. This would result in a much weaker repair and needs to be avoided by careful measurements.

Above the HDT of a resin system it will soften slightly and its mechanical properties will start to fall away however a thermosetting plastic (like epoxy) is NOT a thermoformable plastic so it will not start to flow again such that you could melt it out of your part. It's more likely to become slightly soft and then possible more brittle again before eventually starting to burn if you too the temperature high enough. It sounds to me like you need a thermoformable plastic (aka a thermoplastic) with a relatively low melting point. I'd suggest something like PCL.

An elevated temperature post-cure is not required for parts made with epoxy resin however, post curing parts will improve the mechanical properties of the resin (and therefore the part) and so if you have the means to do it then it's certainly recommended. One major advantage to post-curing epoxy is that you will raise the HDT (heat distortion temperature) of the part meaning that it's less likely to soften or distort in higher temperatures. This can be particularly important for parts like a vehicle panel (i.e. hood/bonnet) which could get very hot in the sun. Without a post-cure there is a good chance that the part would effectively post-cure itself 'in situe' when it's in direct sunlight which can cause the resin to soften, sink and then re-harden. When this happens to a fitted part it's likely to distort the surface finish. A part that had been post-cured prior to installation would not have this problem.

Epoxy resins have very little odour and so it's quite viable to use them indoors (i.e. in your house) without upsetting anyone. The resin is almost completely odourless and the hardener has an amonia smell which doesn't really carry or linger.

In this respect epoxies are very different to polyester and vinylester resin which has a very strong smell and cannot realistically be used indoors. As always, you should still follow safety precautions and ensure adequate ventilation of your work area.

Uncured resins are classed as dangerous goods and would need to be disposed of correctly. For domestic users, usually your local council recycling centre will have a disposal service for such chemicals or containers.

Because cured resins are inert and safe for disposal it's often easiest to mix un-needed or out-of-date resin and hardener together to cure them. Once cured they can be disposed of with general waste.

Epoxy is sensitive to low temperatures so we would not attempt to try and cure the resin at very low temperatures such as below 15 °:C. At those temperatures, the cure time will be lengthened considerably.

One of the most significant problems caused by low temperatures (much below 20°C) is that the resin will be considerably thicker which affects its ability to self-degas after pouring.

Also, curing epoxies are hydroscopic so the low temperature environment may well leave the resin vulnerable to absorbing moisture, especially if the environment is relatively damp or high in humidity as can be found in some outdoor workshops or home garages.

As a result, for best results we always recommend working in an environment that is 20°C or above.

The B stage of the cure is when the resin has cured enough to be firm but still tacky. When touching with a gloved finger, the resin should feel tacky but not leave any residue on the glove.

No, you should definitely not use anything to try and thin down the Epoxy Tooling Gel Coat. The thickness of the gelcoat is intentional to prevent the gelcoat from running or pooling on contoured moulds, allowing a consistent thickness to be applied. If you’re finding that the gelcoat is too thick to apply it’s likely that you’re using it in a cold ambient temperature; at a typical 20°C the gelcoat should not be too thick but at cooler temperatures (which should be avoided anyway for curing reasons) the gelcoat may well be too thick to apply correctly.

It's difficult to give an accurate maximum time because it really depends on the ambient temperature and can also depend (to a lesser extent) on the thickness of the gelcoat. The important thing is that the resin is applied whilst the gelcoat is still slightly tacky, what's known as the B-stage. If the gelcoat cures past this point and feels hard and dry to the touch then its ability to chemically cross-link with the resin has gone and the bond will only be a mechanical one (requiring keying with abrasive paper). Typical gel time is in the 2-3hr region, and it will remain in the B-stage for a little longer but it really is important to test it, rather than time it, when assessing the B-stage.

Moulds made with the Epoxy Tooling Gelcoat can be used with epoxy, polyester, vinylester and PU based resin systems. Both carbon fibre based fabrics and more traditional Glass and natural based fibre fabrics can be used in these moulds.

The quality of the parts surface is down to the quality of the mould surface. The better quality the mould, the better quality the finished part. We would recommend ensuring your mould has a good high gloss and smooth finish prior to its first use, thus ensuring minimal finishing is required on the moulded parts.

Yes the EG60 Tooling Gelcoat can be sanded once cured should you need to make any modifications or repairs to the tool.

Yes, the Epoxy Tooling gelcoat is great for conventionally made epoxy moulds using woven glass or powder bound CSM for the matting.

No, our Epoxy Tooling Gelcoat is too thick to be applied with either a conventional spray gun or cup gun. It cannot be thinned to reduce the thickness for spraying. Brush or roller application is the recommended application method for this gelcoat.

Yes, you can use two applications should you need a thicker coat or wish to overcoat thinner patches on the first application. The ideal time for best bond strength is to overcoat once the first coat has gone to the firm but tacky part cured state. You can test this with a gloved finger, it should stick to the gelcoat but come off with no residue. At this stage the fresh gelcoat will both chemically and mechanically bond with the first layer.

Should you accidentally leave it too long, then once fully cured, you would need to roughly key then clean the first coat, then apply a second coat. The rough key will help the gelcoat get the best mechanical bond it can.

Yes you can make polyester parts in an epoxy based mould. Always use a good quality release agent such as our Easy-Lease Chemical Release Agent to ensure a good release.

Not really (although some customers have bent the rules with OK results). The HDT of our Epoxy Tooling Gelcoat is 60°C which is too low for use with any of our prepregs. We do know of customers who have taken their moulds up to about 75°C without reported problems with is about the very lowest you could cure a prepreg at, given a long enough cure.