The brush making and restoration forum is a popular place, with several members rehabilitating old brushes found in closets, at estate sales, at flea markets, or in antique stores. Most new knots come from TGN.
Quick & Easy Brush Knot Gauge
US coins are a great gauge for judging the appropriate size hole for a particular knot
- Penny = 18mm
- Nickel = 22mm
- Dime = 16mm
- Quarter = 24mm
Note: the nominal size of the coin is not the listed dimension, the hole should be bored a small bit oversize to facilitate inserting the knot without damage. Therefore, the coins correlate to the size hole that should be drilled for the particular knot
- Brush handle
- New knot
- Sharp knife
- Hand-held drill and drill bit
- Dowel with sandpaper wrap, or dremel tool, or dremel drill bit
- Sandpapers in various grades
- Polishing compound (Wenol, Flitz others)
- Fortsner bit
- Dremel grinding bit
- Dremel sanding drum
- Pen vise
- Drill press
- Dust mask or respirator
- Exhaust fan
The first step is to remove the old knot and clean out all the hair or bristles and the glue. Mask off the handle to avoid damaging it. If using a vise, wrapping the handle in leather is effective. Use a sharp knife to cut off as much of the hair or bristle as possible. Then use a hand-held drill or a gimlet to work out the glued-in hair. Some members have reported success using medium-strength ethanol or isopropyl alcohol as a glue solvent, but be careful as this could damage the handle. If using power tools, do so in a well-ventilated area and wear appropriate protective gear.
Try fitting the knot to make sure that the knot is right for the handle cavity, and that the loft match your preferences. At this point you may want to drill into the inside of the handle, to deepen it for a shorter loft. Or you might want to build up the cavity for a longer loft: this can be done using a filler such as pennies or cork. You may also use a dremel or a dowl with sandpaper to widen the cavity, if you want to install a larger knot than the original. Be careful as some handle materials are brittle and may crack or split when drilled.
Clean and polish the handle to your standards. Then mask off the polished surfaces and use epoxy to set the knot permanently. It's best to use an epoxy that takes at least a minute to set, so that you can clean up any excess.