Body fillers - long work time

[EFA]

My car has some very inaccessible but visible areas on the body where it is very hard to get access to sand using any power tools. I have to fill the "rough side" of some grp whihc is inconveniently punctuated with some chassis tubes and get it really smooth and flat. Its areas like this (though I've got it better than this using P38):



I need to find a filler with a very long work time, which can be continually smoothed for about 15 nmins until it starts to cure. If I can wet it with thinners etc to improve the smoothing action all the better.

Anyone have any goo ideas as to a product to use?

[Eagerbeaver]

In this cold weather in the UK, I'm sure I'm getting 15 minutes from standard filler but using very little hardner. I was only filling a panel yesterday and had a similar issue to yours.

Why not try a lean mix in the cold and see how you get on. I store my filler at about 20 deg C then take it out to use in about 10 deg with reduced hardner.

I'm sure I'm seen slow curing filler in a body shop factors.

I've also seen a system where the filler is applied and then the catalyst is sprayed on but you need breathing aperatus for that as it is nasy stuff. Makes isocyanite paints looks like something you'd give your kids to play with.

[EFA]

You see the fillers they use at West Coast Customs etc. on TV and they seem to be very long cure, and self levelling. I need something I can put on like wet plaster!

[singlecoil]

You ay find it best to buy the filler in component form from a specialist GRP supplier. One who will supply the accelerator separately to the resin, filler and catalyst. Resins are normally pre-accelerated which reduces the control over the cure time.