An acrylic edge finish is a specification item that buyers notice instantly and drawings rarely mention, which is how a project ends up with a beautiful panel and a milky line around it.
A signage fabricator in Dubai returned 40 panels because the edges were saw cut and read as white against a dark wall. The panels themselves were correct; the drawing simply said cut to size.
Acrylic edge finish options and where they belong
- Saw cut: structural, to be hidden in a frame
- Diamond planed: clean line, low stress
- Sanded matte: hides tool marks, frosted look
- Polished: clear or flame, for exposed edges
Each finish answers a different question. Saw cut is for edges that end up in a channel; diamond planed gives a clean bright line with minimal stress; matte is the forgiving choice on thick sheet; polished is for edges on show.
Chamfers, flame and annealing
A 0.5 to 1 mm chamfer on a thick panel changes how it reads. A square polished edge on 30 mm sheet looks blunt and shows every handling scuff; a small chamfer catches light along its length and reads as a finished product.
Flame polishing is the fast route and the risky one. It leaves a thermal skin that crazes when alcohol or solvent cement touches it later, so on thick sheet or near a bonded joint, diamond polishing plus annealing is the durable answer.
Annealing matters more than most buyers expect. Machining stress plus a warm environment plus a solvent wipe is the standard recipe for craze lines, and one hour per 3 mm at 70 to 80 C removes the stress before it becomes visible.
For how the edge interacts with the rest of the cut, see acrylic cut to size, and for bonded seams, large panel bonding.
Send your panel drawing with edge requirements marked to oversales@rpplexiglass.com for a finishing quote.
Frequently Asked Questions
What acrylic edge finish options are available?
Saw cut, diamond planed, sanded matte and flame or diamond polished. Clear polished edges transmit light; matte edges read as frosted and hide minor tool marks.
Does flame polishing weaken the edge?
It introduces thermal stress. A flame polished edge on cast acrylic looks superb and crazes under solvent attack later; a diamond polished edge has far lower residual stress.
When should an edge be annealed?
After machining on any panel that will be exposed to solvent cleaners or heat, and always on thick sheet over 25 mm. Annealing at 70 to 80 C for one hour per 3 mm of thickness removes the machining stress.