questions about a handle

[wrinkles2]

I have a couple boar knots coming my way in the next few days, one I Have a Handle for.
I am searching for a Second handle; here is where my questions start.
First
Here are the Dimensions of the knot:
Knot (hair tuft as it comes out of sleeve): 20mm
Sleeve diameter (minimum size hole would need to be to accommodate the knot: 21mm
Collar diameter, outer edge to outer edge (this isn't really that important, as most people just leave the collar to sit flush with the handle - meaning the collar is visible, but if you don't like that you would need to account for the size): 24mm
Height of sleeve: 12mm (13mm from bottom of sleeve to top of collar, but again, the collar will sit flush so it wouldn't actually enter into the hole in the brush handle)
Hair loft: 55 mm
Total height from bottom of collar to top of hair: 68mm
To Be Clear, the Collar is the rim that the hair comes out of and not the plug that gets glued in the handle right?
If so, I Do wants the "Collar" to be visible, so that would bring the knot back to 21mm.
Now for my next question, I understand that these knots expand so how big does the hole in the handle have to be drilled to accommodate it?
I have a few questions about my other handle and knot, but will post them later.

 

[mattdenicola]

THe knot itself is 20mm, but the surrounding sleeve adds a bit of diameter all around, coming to a total of 21mm. So the size hole that has to be drilled is 21mm. The knot "expansion" is not really applicable in this case, because the knot is already in the sleeve. So you are drilling the hole to accomodate the sleeve, and you don't need to account for the hair expanding inside the brush.

The only variable really is exactly how your handle will accomodate the collar. I would personally just drill a 21mm hole to a depth of at least 12mm, then allow the collar to sit flush with the handle. If you want to get more nuanced with it, I think you may just have to wait until you have the knot so you can see what you need to do.