Plenty of posts describing the difference between the knot shapes, including pictures for a visual comparison. In addition to that, fan knots do not have the glue bump. In my experience, anyway.
I use both. But I face lather, so as long as it works. More utilitarian I guess.
In my experience the knot shape has no bearing on whether you can feel a glue bump. All knots have a glue bump or maybe better described as the top of the glue mass holding the fibers together. The higher the glue mass the more likely it will extend beyond the top of the handle.
I can discern between any brush I have with a fan knot and a bulb one blindfolded. Either during its use or just simply by feeling the knot near the top of the handle. Of course, that is for all the brushes I have. I can feel the glue bump for all the bulb knots (and some of the hybrid) because the glue bump projects over the top of the handle.
You sound very knowledgeable. I admit, I do not know how all knots are made. My statement was not correct indeed, and will rephrase it. In my experience, the fan brushes I use do not have a glue bump extended past the top of the handle. Very likely due to a shorter glue plug. And that makes for me a better brush.
I believe it depends on the brush manufacturer how deep they set the knot in the handle.
That being said, I prefer fan brushes over bulb. I consider all fan brushes I have being better brushes, when it comes to performance.
I like fans.
And bulbs.
And bulbs.
The only way I can really tell if the glue bump extends above the top of the handle is by pushing a straightened paper clip down through the middle of the top of the knot until it stops. I mark the clip at the top and then measure it.
My problem with glue bumps that extend above the top of the handle is that they distort the actual loft of the brush. Paladin Brushes list their loft and then what they call free loft ( loft - glue bump = free loft ). I believe free loft is the actual loft of the brush.
I have a custom made brush (I won’t name the manufacturer) that I ordered as 24/52mm. When I received it it felt very stiff. I measured the glue bump at 10mm above the top of the handle. So what I have is really a 42mm loft. The manufacturer agreed to do a second brush which I just received and is perfect with a 0mm glue bump. FYI both brushes have fan knots.
Because this was so fresh in my mind, I couldn’t help but comment on your post.
I prefer a fan shape with a smaller knot. But I have a relatively larger knot in a bulb from Shavemac that I also like. Being a face latherer, my favorite brush has been a Simpsons Colonel X2L Manchurian, a 21mm knot with 45 mm of loft. My Simpsons Chubby 2 is a bulb shape 26mm knot x 52mm loft in the platinum synthetic. It is a perfectly fine brush, but it feels too big in my hand, and too large on my face. However, many, many B&B members love the Chubby 2, so YMMV.
Have you ever considered that first brush as atypical for a fan brush? Maybe even a defect in the knot?
I dislike brushes with glue bump extended past the handle.
The only way I can measure the size of the glue bump that extends past the handle is by doing this: "pushing a straightened paper clip down through the middle of the top of the knot until it stops. I mark the clip at the top and then measure it."
If I want a quick assessment, I just pinch the knot right above the handle.
Just how I like them.
I've noticed my old Semogue boars have huge glue bumps. They perform great. But I have to resist looking for the bump. Just knowing it's there bothers me.
Oh, boars. For some odd reason I considered this discussion around badger knots. I used to be a fan of Semogue brushes. I am more reserved these days.
Yes it would be atypical/defective for any type of knot be it fan, bulb or hybrid that has a 10mm glue bump. I have another brush from the same manufacturer that has a negative 4mm glue bump. I always thought it was a little floppy, but never measured it until I ran into the 10mm glue bump. My 4 other brushes from this manufacture are all 1-2mm positive bumps. My 11 Simpson brushes are all from 0-3mm positive.
I would expect Simpson to be consistent glue bump wise because they don’t customize their lofts. I would also expect a manufacturer that customizes each brush to have a more difficult time keeping bumps consistent, but 10mm is way too much.
