Just bought a hellcat and an aftermarket canopy. I want to leave the canopy open but wonder what to do when air brushing it. Any hints or tips?

I usually use sponges..... On larger scales I cut down those cheap kitchen sponges from the dollar store. (the really soft ones. For 1/72 scale I simply use those tapered spongy ear plugs I get from work. (I roll them smaller, them insert them, and they expand for a tight seal.

Nice sponge idea

I usually take small pieces of tape and slide it down vertically 2-3mm into the cockpit with sticky side out, then I push the sticky part into the cockpit 'lip/edge'. I do this all the way around and then form a tent to close it at the top.

I use cottonballs to cover up my cockpit.

I use damp tissue

I close the canopy using maskol as glue.

Sticks sufficiently for keeping the canopy in place during the brushing and is fairly easy to open again afterwards.

Onloy disadvantage is that maskol can be a real pain to remove.

Here's another question, sorry to go . How do you mask the interior of your wheel wells? I usually fill the area with silly putty, but it sometimes lets paint onto the wheel well sides. Any other ideas?

temporarily tack the gear doors in place while you spraty the wings, belly!

same system as for a canopy (or any other interior "hole"). I fix the parts which later will be in an open position in a closed position using maskol.

Either tacking the covers on with blue tac, or the good old cheapy sponges cut to a close shape.

I usually fill mine with balls of rolled up masking tape