These have been answered before so I thought I knew the answer...

Polished out (mostly)0 flashlines with a Dremel bit. That left a roughly flat bit, with a couple of little scratches where I went a bit OTT. Notrhing dramatic.

Also had some scratches and a spider crack. So I V'd these out, patched the crack behind with mat, cleaned them and dribbled gelcoat along the cracks to fill. Left it for three weeks (due broken garage door) covered in clingfilm and tape to dry.

Today I started trying to polish the new gelcoat flush. But it mostly isn;t solidly dry - a bit tacky still. So damp wet 'n' dry just makes a mess and puts fine scratches in to the surrounding proer gelcoat.

Where have I gone wrong? Wrong mix? Not en ough time? Wet n dry too wet? And how do I fix it?

Thanks in advance..
Ed

Gel coat will stay tacky if there's air present during curing. Sounds like the clingfilm didn't completely exclude the air (was it completely flush up against the gelcoat?).
Strictly speaking for that job you needed flowcoat....
You might need to remove and redo using flowcoat....

As above, just to clarify, flow coat is basically the same as gel but with a little bit of liquid wax in it, as the gel is hardening the wax rises to the surface and lets the gel set hard.
if you already have some gel just go to your local GRP chaps and get some wax, you will only need a drop or two, stir it into the gel before adding the hardener, this will take a while as it takes a lot of stirring .
Cheers.

Will try to retape and let it dry first - might just work......

NOw got some wax, so I'll dig it out again - how much wax do I need?

thanks

About the same amount as the hardener.