Spraying puts an even coat of glaze on shapes that cannot be dipped and allows gradients and overlaps that no other method gives. It also atomises glaze into the air, which makes it the one glazing method with a real and immediate need for extraction and a fitted respirator.
When spraying earns its place
On large pieces that will not fit a bucket, on sculptural forms with awkward surfaces, on tiles where dipping marks would show, and where a graded transition from one glaze to another is wanted. For a studio making mugs and bowls in batches, dipping is faster, more even and far less trouble, so spraying stays a specialist option.
What it needs
A compressor, a spray gun suited to glaze rather than paint, a turntable, and above all a spray booth with extraction that vents outside. Glaze suspended in the air is respirable silica-bearing material and it will settle over everything in the room. The equipment cost is the real barrier, and it is why most small studios dip.
Getting an even coat
Thin the glaze more than you would for dipping, keep the gun moving, and build the coat in several light passes rather than one wet one. Watch the surface sheen: a coat that starts to look wet is about to run. Rotating the piece on a turntable while spraying is what produces the evenness that makes spraying worth the setup.
The safety point, stated plainly
This is the one glazing technique that puts material directly into the air you are breathing. A fitted respirator rated for fine particulates, an extracted booth and wet cleaning afterwards are the whole requirement, and none of it is optional. The duties written into COSHH fall on employers, which is exactly why a hobbyist needs to know the practice rather than assume someone has arranged it.
Questions people ask about glaze spray
Do I need a spray booth to spray glaze?
Yes, with extraction that vents outside, plus a fitted respirator. Sprayed glaze is airborne silica-bearing material.
Is spraying better than dipping?
For large or awkward pieces and for graded effects, yes. For batches of ordinary ware, dipping is faster and more even.
How thin should glaze be for spraying?
Thinner than for dipping, and built in several light passes. A coat that looks wet on the surface is about to run.