Removing excess plastic sprue from uPVC window frame welds requires precision to maintain the integrity and appearance of the frame. The following step-by-step guide should get you on your way.
What you will need
- Quarter Moon Knife (for larger pieces)
- Fine grit sandpaper or file (for smoothing welds)
- Heat gun (optional, for softening the plastic)
- Solvent cleaner and soft cloth (for cleaning)
Step-by-step process
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Prepare the area
- Clean the area around the welds to remove any dirt, dust, or grime.
- Protect areas surrounding the welds to avoid scratching or damaging.
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Cut off large sprue
- Carefully slice off any large sprues using a Quarter Moon Knife. Angle the blade to avoid gouging the frame. Work gently without too much pressure to avoid damaging the frame or leaving deep marks. Move the blade slowly and in one direction for a cleaner cut.
- Particularly hard or brittle sprue can be gently warmed with a heat gun to makes the plastic more pliable and easier to work with. Be careful not to overheat, as it can warp the uPVC.
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Smooth the welds
- After large pieces are removed, smooth down the remaining small excess using fine grit sandpaper or file. This ensures the weld is flush with the rest of the frame.
- If using sandpaper, rub in small circular motions to blend the area smoothly.
- Keep checking to ensure you're not over-sanding, as this may create dips in the surface.
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Finishing touches
- Clean the area with a uPVC solvent cleaner to remove any dust or residue from sanding, and wipe down with a soft cloth.
- Check the weld to ensure it looks uniform and smooth.
By following these steps carefully, you can remove excess plastic sprue from uPVC window frame welds while preserving the quality of the frame.