Shaving Brush Education: Loft, Size, & More!

An important element that's often overlooked for brushes is loft. The emphasis tends to be on size rather than loft, but the two are so intertwined that in order to get an accurate representation of how the brush feels when you talk about knot size, you should probably be talking about loft too.

Size of the knot
We should talk about size first to start things off. The size of your knot is going to correlate to how much hair can be packed into the knot. The bigger the diameter, the more hair its going to hold, and typically the denser its going to feel before being put in a handle.

Loft of the knot
The loft of the knot is going to have an impact on the the splay and backbone of the brush. When you set the knot a bit deeper it's going to have a smaller circumference, look more densely packed, and have more backbone. A knot set higher will be the opposite. I'll provide a visual representation of knots at different lofts below and how big of an impact it can have:

Same 26mm Gelousy size knot, just set 17mm 14mm 10mm deep (Left to Right)

26mm SynBad Knot at 15mm (Left) vs. 24mm SynBad Knot at 10mm (Right)

Same 26mm Gelousy size knot, just set 17mm 14mm 10mm deep (Left to Right)

26mm SynBad Knot at 15mm (Left) vs. 24mm SynBad Knot at 10mm (Right)

Badger vs. Synthetic - is there a difference for setting loft between the two?
Yes. The reason typically has to do with re: circumference of the knot. Badger is going to bloom when it's exposed to water. Synthetic is not. So when a badger becomes been exposed to water/bloomed, it's circumference will expand. Because of this, typically you'll want to set a badger at least 2-5mm deeper than a synthetic knot. For example, Badger set at 15-17mm tends to be a good depth. Whereas synthetic, around the 12-15mm range tends to be best. So can you change the feel of a knot based on how deep you set it in a handle? Can you make a knot typically known to have less backbone feel like it's got more? Absolutely. Backbone on a knot is definitely adjustable with how deep you set it in a handle to a certain extent. Is a cashmere set at 15mm going to have the same backbone as a tuxedo at 12mm then? Well, no. But it's going to be closer in terms of backbone should they have both been set at 12mm. Since there's no real objective way of measuring backbone theres also no real way of objectively telling you how much closer Knot A feels to Knot B as a result of setting it deeper, but I can tell you it does make a difference, and hopefully the pictures give you a visual representation of how that's the case.

Side Note: Shape of the knot One thing I felt was worth mentioning after reading through this that was also worth mentioning is the shape of the knot. A bulb shape is going to have more backbone than a fan shape. Bulb shapes can vary a bit, so it's good to get a look of the knot from the top to see it's circumference (or ask your vendor which knot has smaller circumferences from the start)