Inlay

It is possible to create inlays on 3D prints using a number of different methods.

Wax crayon inlay

Formlabs mechanical engineer Christian Reed has developed a method for creating colourful inlays on 3D prints using wax crayons.

ABS slurry inlay

Benefits

Creating inlays using ABS slurry has a few benefits compared to wax crayons:

• Its hardwearing
• Its very cheap to create a lot of slurry
• 3D printing people are likely to already have acetone and ABS
• Its very easy to remove the ABS from areas of the print you don't want it to be using acetone on non ABS prints
• It sets quickly
• Its easy to get a good finish using a small bit of acetone on a cloth and sanding if wanted
• No equipment required
• You can mix filaments to make different colours
• Allows for the same post processing as normal prints.

Downsides

And some downsides:

• Colours are limited to what you have in stock, buying a whole new roll of filament is not really practical or economic
• You need to do a few layers to get a good finish, as the acetone evaporates it shrinks, thick slurry means less layers
• ABS slurry takes a few hours to make

Usage

ABS slurry inlay is possible on many kinds of materials including PLA and ABS prints, it is easier to achieve on the top or bottom of the print where there are no ridges to sand off post processing.

ABS slurry inlay is a lot easier on PLA prints, you can clean off excess slurry with acetone although the acetone can stain the PLA a little, but this can be avoided by being careful or sanding the print.

ABS bonds very well but needs to be either sanded or wiped with acetone to get it to a presentable state. Wiping excess using acetone works especially when the slurry hasn't fully hardened, but its easy to make the print soft if you're not careful.

Tips

• A thicker slurry is easier to apply and shrinks less when drying, but too thick and it won't get in all the corners.
• Deeper inlay tracks and much easier to apply slurry to and result in a stronger bond between the inlay and the print.
• It is much easier to accurately mix different filament colours when already mixed as separate mixtures of slurry.

Nail varnish inlay

Nail varnish inlay is very similar to ABS slurry inlay in that acetone is the solvent for both ABS and nail varnish. The main benefit to using nail varnish as an inlay is that it is available in a very wide range of colours and can include special materials like glitter, it is also very widely available.