A corner trowel is a plastering tool with a steel blade folded at a right angle (90 degrees), used to finish the corner between two surfaces straight and neatly in a single stroke. There are versions for internal corners and for external corners.
Two versions
- Internal corner trowel — the blade is folded inwards, for the re-entrant corner between two walls or between wall and ceiling
- External corner trowel — the blade is folded outwards, for the projecting corner, for example at a reveal or a wall corner
How it works
After applying and smoothing the plaster or render layer, the plasterer runs the corner trowel along the corner. The folded blade presses both surfaces at once and gives a perfectly straight, sharp corner line. This is faster and more accurate than finishing both surfaces separately.
Application
- Plaster and render work — finishing corners on walls and ceilings
- Plasterboard work — finishing the joints in the corners after filling
- Repairs — restoring damaged corners
For a durable, impact-resistant external corner, the corner trowel is often combined with an embedded corner bead.
Related terms
- Plastering
- Plaster layer
- Corner bead
- Float
- Trowel
- Screed
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