This will act as a guideline and will help you achieve the shape you are.
How to shape abs plastic sheet.
Measure the size of the of the overall piece you need.
Dipping the abs into a bath of cool water will help quickly lower its temperature so it will hold its new shape.
A common and safe method of reshaping abs plastic is to use boiling water which reduces risks involved with accidentally overheating abs.
Secure it with a clamp to prevent the material from moving.
Leave room between the guide lines you ve drawn and where you cut.
Depending on how deformed your part was originally you may need to repeat the process two or three times slowly bringing the abs back into its proper shape a little more each time.
Water boils at 212 degrees fahrenheit at which point abs becomes soft and rubbery but will not burn.
Then mark the cutting line with a highlighter.
Make straight relief cuts from the outside of the plastic to the curves.
Use a plastic cutting knife to cut the sheet down to the general overall size.
Make several scores along the guideline.
Using a plastic cutter prepare the work surface and lay the plastic on it.