easy double sided tape removal from plastics
When engraving thin plastic (or any type of material) on a cnc machine, double sided tape is one of the methods for securing the material to the worktable. Most double sided tapes do a great job holding the material down while engraving or cutting. They are, however, messy and sometimes problematic to remove after the job has been cut, especially if the parts are small and the material thin.
This procedure is particularly relevant when trying to cut thin plastic, although it will work with any thin material.
My method to remove the tape effortlessly after cutting is as follows:
Tools needed:
1. Heat gun at low setting
2. metal spackle tool
3. bench vise
4. 1/4" thick wood board used as a jig for cutting thin material. Mdf or any straight and stiff material will do. This jig should be large enough to accomodate the material you want to cut plus room for clamps.
Method:
2. Apply the the double sided tape on your plastic or thin material. Then attach your material on the jig, centered so that you leave room for clamps or any other method for secure it to the work table.
3. Secure them on to the cnc worktable.
4. Cut away.
5. After the material is cut, remove the combo and hold one end of it on a bench vise.
5. Now use the heat gun from the rear of the jig to heat the surface while you place the scraper between the cut pieces and the tape.
6. As you would when peeling paint, keep the heat gun just a bit ahead of the scraper and in a rotating motion so as to prevent burning of the wood.
As the wood backing heats up, the tape adhesive softens to a point where you can easily detach the plastic, with no risk of breaking or melting the plastic. Just look for the "sweet" spot between heat, adhesive and speed of removal.
The plastic pieces, still warm, make the removal of the left over tape very easy and clean.
The jig prevents damage to the plastic by acting as a heat sink, yet allowing enough heat to soften the adhesive so that removal is painless. The vise allows full control of the heat gun with one hand, and the scraper with the other.
