If you paint commecial dolls house windows or doors or custom made miniature doors or windows you have built before you paint trim sections, you have to paint when the item is fully assembled. Rather than mask off the window to create a clean painted edge, which can leave sticky residue on your 'glass' surface, you can use a plastic razor blade,or something similar (a stiff plastic glue spreader) to tidy any paint brushed onto the window edge. This method works for tidying paint jobs on plastic or glass windows or other surfaces (plastic and metal models), as long as they are fairly ridgid and relatively flat or have a defined mold line along the painted line you want to clean up. Of course, it also helps if you use the correct paint brushes or painting tools for painting your miniature.
Clean as You Go - Whenever possible, I clean up acrylic paint strokes that run over an edge, using a stiff plastic glue spreader (or the center of a warm foam bush, pulled free from the old foam)covered with a damp thin piece of cotton rag pulled over it and held in place with masking tape. This simple tool lets me wipe up missed marks along my straight edge while the paint is still damp, without damaging the surface. If that is too difficult to do, I allow the paint to dry, and neaten the edge with a plastic razor blade, or some other thin hard plastic edge.
If cleaning as I go doesn't work I use the following technique to remove dried paint from plastic, metal, or glass surfaces.
Use acrylic paint - it is usually easier to remove from glass and windows. Enamel paints may damage some clear plastics, but the same method can be used as long as the paint hasn't bonded to the surface.
- Allow the Paint to Fully Dry - If you prefer, you can use a damp thin rag, held over the end of a glue spreader, or a plastic razor blade, to wipe up any wet paint you inadvertently paint over the clear sections of your window as you go, but if you miss any areas with this method, allow the acrylic paint to fully dry before you attempt to remove it from the plastic and you will get a cleaner edge.
- "Cut" the paint free at the painted edge - When the paint is fully dry, use the 'sharp' edge of a plastic razor blade (or thin hard plastic straight edge or glue spreader) and run the blade along the edge where the painted surface joins the glass or clear plastic. This will cut the extra paint layer free and keep the painted sections neat, without any possible tearing of the main paint job.
- Scrape the Paint Off the Glass - Use your plastic blade to carefully scrape the paint free of the glass or clear plastic, applying gentle pressure using the blade flat against the glass. Take care not to push the glass or clear plastic out of the frame,and work gently in one direction at a time, clearing the excess paint off each section without rubbing the blade back and forth over the plastic several times.
Provided you use a clean plastic blade, you will not scratch the plastic surface you are using as glazing for a dolls house.
Cleaning Up Straight Paint Lines on Plastic or Metal Models - The same technique works for cleaning up straight paint lines on metal or plastic models. Cut the line where you want it to be, then scrape the paint off on the 'wrong' side of the line. Usually this works best if you have a line defined by a part on the mould (a door edge on a plastic model car for example.) Just take care to cut the paint line with a fine plastic blade so you don't damage your model, and scrap the excess paint off once you have separated the excess paint from the line you want to keep.
