How to select A knot size for existing handle?

[Wsamsky]

So I bought this brush http://www.royalshave.com/p/411-072/rs_PB2_brush.html and I want to replace the knot because it keeps shedding. I wantto get something from TGN but am confused about what diameter to get. The website size the existing on is 27 mm, does this mean I need a 27mm or will a smaller knot fit as long as it's glued down?

Also when removing the old knot do I just yank it out?

 

[Munxcub]

Get the knot that is closest to fitting as you want a close/tight fit. Otherwise you'll see all kinds of gap and glue and stuff around the knot base.

Yanking it out I doubt will work, the way I do it is I cut the hair down as close as I can, and use a forstner bit of the size I need and drill out the old knot base. You can also use regular bits, dremel, whatever it takes to get the handle bored out to the size/depth of your new knot. If the old knot is really loose maybe you can just pull it out, I don't know.

 

[LarryAndro]

I wish I had purchased a caliper for measuring the knot diameter and the diameter of the hole when I started. For under $10 at Home Depot, I could have saved myself some squinting with a ruler.

Get a caliper. Measure the exact inside diameter size of the brush hole in millimeters. Then, compare to the following and you should have a pretty good idea which knot to buy. Not a guarantee. But, you should be in the ballpark.

I have purchased knots from several suppliers, and these diameters are fairly consistent...

A knot base with a 18.5mm diameter is for a 20mm brush.
A knot base with a 20.5mm diameter is for a 22mm brush.
A knot base with a 22.5mm diameter is for a 24mm brush.

I hope this helps.

 

[PozzSka]

You'll probably have to drill the old knot out (after cutting it down to size) as mentioned above.

Then measure the hole left (1" = 25.4mm approx.).

If the hole measures the listed 27mm, you'll probably end up buying a 26mm knot...if the hole measures closer to 29, you may end up with a 28mm knot. (I'm not sure if anyone makes a 27mm knot, haven't seen one)

Ask your vendor about it if you aren't sure. They'll help you out.

You could also contact them and mention that the brush is shedding badly (take a couple photos) and maybe they'll just replace it.

 

[melyus]

Check Ian's quick reference chart , i hope this helps.

http://www.badgerandblade.com/vb/showthread.php?t=139023

 

[Hex]

I have wondered about this as well.

I have done about 10 brushes and always buy the knot to be the same size as the diameter of the hole.

Then, since I wanted a shorter loft, I expanded the hole accordingly.

So, for this simple example, wouldn't I be better off to buy a smaller knot.

Hole Diameter = 22mm
Knot size at the plug = 22mm
Knot from TGN = 22mm x 62mm, Finest Fan

So, If I were set this knot to be a 46mm loft, what would its diameter be 16mm up from the plug.
Perhaps I would have been better off to buy the 20mm knot instead of expanding the handle to fit the 22mm.

For now, I plan on sticking to the old technique.

The reason I ask is that I had one rather small bakelite brush that, after expanding the hole, had somewhat thin walls. So much so, that if you look close, you can see the knot through the wall.

 

[PozzSka]

I have wondered about this as well.

I have done about 10 brushes and always buy the knot to be the same size as the diameter of the hole.

Then, since I wanted a shorter loft, I expanded the hole accordingly.

So, for this simple example, wouldn't I be better off to buy a smaller knot.

Hole Diameter = 22mm
Knot size at the plug = 22mm
Knot from TGN = 22mm x 62mm, Finest Fan

So, If I were set this knot to be a 46mm loft, what would its diameter be 16mm up from the plug.
Perhaps I would have been better off to buy the 20mm knot instead of expanding the handle to fit the 22mm.

For now, I plan on sticking to the old technique.

The reason I ask is that I had one rather small bakelite brush that, after expanding the hole, had somewhat thin walls. So much so, that if you look close, you can see the knot through the wall.

I would buy the smaller knot.

You're always going to set the knot 8-16mm deep into the handle anyways. I've restored 5 brushes now, and in two of them , the hole measured about 21.5mm, so I got 20mm knots they are perfect.

In two of the other brushes, the holes measured 22.2mm, and 24.6mm. I bought 22mm and 24mm knots, they were too big, so I had you do what you mentioned and widen the hole slightly.

Always round down, IMO.

 

[Munxcub]

I don't mind widening the hole a bit (not terribly difficult with the sanding bit on my rotary tool). That way I can cram more badgery goodness in the handle. heh