decals on top of oil-based wash???

Yes Nick you can apply future over this wash. But oil paints take a long time to cure and you should wait until they are fully dry to apply the coat of future. I usually let my models sit at least 24 hrs before applying future over oil washes and I live in a warm dry climate.

But you state that you already had a coat of future on the model before applying the wash. if you only put the wash into panel lines and receses and not over parts you wish to decal I would apply the decals now. But if there is wash over parts needing decals then apply a coat of future once the wash is dry then decal.

Once the decals are on seal them with a coat of future or dull coat depending on the finish you are looking for.

Hope that helps

nwilliams hi
thanks very much for your attention.
i kind of thought that's what i should do, but you know how it is when yu try something for the first time, you need a litlle reassurance!
although the wash was only meant for the apnel lones it ended up all over the tank (not as much of a disaster as it sounds!), so another future coat is in order.
re curing time that's not a problem; i can just be getting along with the 109 group build!!
many thanks once again.
regards,
nick

Let us know how it turns out.

Glad I could help.