I have painted lead (metal alloy) models for 50 + years. Now I have a 3D resin model ship to paint.
1. Do I wash in soapy water as I would resin casting ?
2. What primer - if any- is recommended.
Advice and wisdom appreciated
Yes,
Wash.
Then either acrylic or primer spray
No wash, just a base coat of black then colour on top.
I don't really treat 3d prints any differently to metal figures - so straight onto priming.
There are two very different types of 3d prints, resin prints, washing will be pretty pointless as the resin is incredibly hydrophobic. If these prints are a bit tacky, then leaving them in sunlight will tend to allow any last bits of resin to cure.
The other filament ones are just melted plastic, so you can wash, but there is nothing particularly to wash off from the printing process
Having painted loads of 3d printed vehicles and aircraft, I just treat them as any other model kit - Humbrol enamel undercoat, leave for 24 hours, then paint in usual acrylics.
I don't recommend acrylic undercoat as I found metal wargames models chip a lot easier then those undercoated in enamel.
many thanks for the solutions - we will all have experience of painting 3D as time goes bye.