Hello Mike

A 10mm crack doesn`t sound much, unless it`s 10mm wide!

I would use use P38 filler……… Just because I have it in stock

Rub it down when set and repaint

Why don`t you post a picture of your renovation?

Bob

Michael

If that's a split in timber then I would fill it from the inside with P38 until the filler oozed out from the crack on the outside. I'd then put a patch of glass-cloth over the area on the inside, using resin in the normal way, to reinforce the wood and prevent the split from getting any bigger. As Bob says, you then rub down the "ooze" on the outside and repaint it. Be sure that the whole thing is completely dry before you start any of this, and don't go near it with silicone sealant (because nothing else will stick to that stuff once it's set e.g. paint, other fillers).

I'm constantly amazed that models which look so serviceable on the outside are such cr*p inside!

Dave M