Thread: How do you measure a brush/brush head?

I want to replace the brush in my stainless steel handle. Are the openings of a standard width? That is, when a brush says it is 24mm or 30mm, is that referring to the height of the brush, or the width of its base? Does my question make sense?

The width at the base, known in terms of measurement, as the 'knot', is the diameter, best measured with a calliper. The height of the exposed bristle, from where it shows from the top of the handle, to the top of the bristle is known as the loft.

So, if at Whipped Dog I can choose between a 24mm and 30mm, is he referring to the knot or the loft, do you think?

Originally Posted by Smyth

So, if at Whipped Dog I can choose between a 24mm and 30mm, is he referring to the knot or the loft, do you think?

I would assume it was the knot. In general you would get both measurements, but the knot is the critical one for fitting to your handle.

Hmmm. I don't have access to a caliper, so I was hoping that aspect was standard. Thanks for your help.

if you have a ruler with metric on one side, you should be able to tell the difference between 24mm or 30 mm, or if you don't they're 24 mm = 61/64 inches (a little under an inch, and 30 mm is 1 11/64 or more than 1 1/8...however, your handle could be 22 mm or 32 mm or some other diameter. 24 and 30 mm aren't the only knot sizes. Send it to somebody in the classifieds and have them set a new knot for you. Oh and measure the loft you want.

Originally Posted by Smyth

Hmmm. I don't have access to a caliper, so I was hoping that aspect was standard. Thanks for your help.

You could remove the old knot and just measure the diameter of the opening.

In regards to knots, the dimension listed is always the size of the knot plug. The loft is not usually listed because it can be set to any value when the knot is installed in the handle. In general a 30mm knot, for example will fit in a 30mm hole in the handle, but this will be at the loft the knot has. If you want to set the knot deep the opening of the handle will have to be bigger and it is determined by the loft you want to achieve.