> ... hair dryer to warm it up and it worked to a degree but the resin gets thiner and runs to the lowest point of the mold and leaves voids at the outer edges

Yup that can happen. From your description so far, I suspect you are struggling with an epoxy that has a higher than desirable viscosity and also what sounds like limited hardener selection to control pot life. Both of these parameters are working against you in a hand layup (non bagged) application. So what sort of epoxy are you using? What is the rated viscosity at room temp? What is the ambient temperature when you are doing the layup?

Ideally you want a thin viscosity resin/hardener mix so that it will wet out the matrix properly. The thinner the cloth & tighter the weave, the more important this is if you want to acheive a low weight layup. From my experience, a R/H mix in the 300-500 cp range at room temp is perfectly fine & you will get excellent results. But if for example you have a mix with 2500 cp viscosity (like very thick honey), even by heating it moderatley, you may still be at 1500 cp - still too thick. If you are using a resin rated at 1000 cp at 70 deg F & your shop is at 60 deg F, you can expect proportionately thicker viscosity - say 1300 cp. A good resin manufacturer will provide this data. Reduced viscosity will also help your entrapped air problem. Consider what happens with an air bubble 'trapped' in a glass of water (viscosity = 1 cp); the bubble immdeiately races to the surface & pops. It is very difficult for it to hold the air from doing otherwise. (ok technically water has a higher density which helps a bit, but not to the same degree).

It is also important to have a good range of hardeners in order to control set up time (pot life). If you can get a fast hardener like 15-20 min & a slow like 90 min, then you will have the ability to custom blend hardeners to suit the layup job. The resin:hardener ratio stays the same. Even if yu have a thin resin, it will be difficult to keep it in place with a long pot life for the reason youve stated - drain off. There are lots of epoxies on the market, but you have to select the right one for the job.


> The pot life of my resin also stays thinner longer when it is warm the colder it is the quicker it thickens so it just was not practical.

Hmmm... does not sound right. Heat promotes the curing, pot life is reduced, exotherm is accelerated, molecular chains are building meaning the mix viscosity is increasing & heading towards solidification - the opposite to what you are saying.