I will be redoing the knot in an Etsy brush I purchased. Unfortunately, the knot came out so I decided I would like to make some changes based on the recommendations of other here. This is a Virginia Sheng Silvertip knot as supplied by the Etsy seller. The knot is 65mm tall and about 58mm loft (after washing and use). Free loft is 46mm. It is a 20mm knot. The handle is just beautiful acrylic. It was drilled to a depth of 7mm. Since it was only used once, the knot is much softer than the other badger brushes I own and it does have good backbone. Changes: The knot was glued in with epoxy. I will be changing to GE 100% silicone. I have picked up a 3/4" Fostner bit to drill it to a depth somewhere in the realm of 12mm. The change to silicone is to ensure easier removal should alterations be needed. Going deeper is partly due to this being a silvertip and desiring to prevent too much bloom. The brush, as is holds a ton of water but resists to yield it. I expect going deeper might stiffen the backbone slightly but may aid in release slightly. I suspect drilling deeper would further help in this regard but I do not want to go too far. It is easier to drill deeper and not as nice to have to add a spacer. Any thoughts, comments or suggestions are greatly welcome. I am planning on doing the drilling tonight so the sooner the better. Thanks
After drilling you might consider filling the hole in the middle. I've used plaster of paris, hot glue, or epoxy on other hollow vintage handles. I like the heavier weight a bit better. You could do the same the thing will BBs or ball bearings and hot glue (or silicone).
The silicone II is a good choice. Give it a good 24 hours before you lather with it, and go easy the first few times. After that, it should be fine. Also, filling the hole is a good idea. If you drill too deep, you can use a coin to cover the bottom and raise the knot. Nice handle BTW.
Doesn't your wrist get tired with the increased weight? Won't you be able to 'whip' the lather faster getting more aeration with a lighter brush? If I decide to add weight, I might grab a brass or other rod or bolt cut down to fill it.
It's just me. I like the added heft in the brush handle. You may not like that. One suggestion would be to fill the hole with something loose that you can remove later (BBs, etc.) and then put a piece of masking tape over the top. Use a glue that would not be as permanent, like rubber cement to set the knot. Test it in your hand. You probably won't be able to use it with soap, but you could do a dry swirl to get a feel for the weight. If you like it, take the brush apart and then fill the hole with your hot glue (or whatever) and your final weights (brass rod, etc.), then, glue the knot with the permanent glue. Just a thought.
I would drill in 2mm increments, if you don't want to add spacers. Also wrap a piece of tape around the drill bit so you know where to stop. (You probably already knew that). Edit: I agree with you wanting to drill it out to at least 12mm. My preference is about 14mm myself.
I have a 20mm Virginia Sheng Silvertip that was pretty floppy so I set it in a 20mm deep hole by almost 24mm wide (to accommodate the glue bump), for an effective 45mm loft. It's pretty soft and has moderate backbone that works great with creams. Good idea to go in small increments & test fit along the way, then stop when your happy.
In my dozen or so restores, I have learned, at least for me, to set the knot (badger) where the top of the glue bump is just below the handle rim. When I squeeze the bottom of the knot at the handle rim, I feel none of the glue bump. It has the soft feel of a badger with a firmer backbone. I have several Forstner bits. I drill a little and measure a little until I have the desired depth.
On one of my "flashlight" brushes the hole was a bit deep for the knot I used. So as to not add much weight to it, I used nylon washers to raise the height. Good to use if the weight is where you want it, but I did use a nickle once.
Not to be picky but I would polish the top edge of the handle prior to installing the knot. It looks like a saw cut in the photo's. A sheet of 3000 grit sandpaper and a little elbow grease should have it looking the rest of the handle.
Keep the suggestions coming. Tonight turned into date night so work might need to hold off until Friday or the weekend. Thanks
Anyone have a good way to hold the handle without marring it in the drill press? I was at least thinking of wrapping it in painter's tape and not sure of the best way. Thanks in advance
In separating the two pieces of a Rubberset 400 I used strap wrenches. Harbor Freight sells a 2 piece set for cheap. The rubber strap that does the holding is quite soft. Maybe a bit of automobile heater hose? Many parts houses sell it by the foot.
You can make some wood vice jaws with a V- notch cut in the center. The 100 % silicone is a great medium to make a mold out of the handle, and fill er up with hot glue and you have another handle !
The brush was wrapped with blue low stick painter's tape and then slid into a piece of toilet paper tube ripped to length to protect the finish. I used my Walker Turner drill press and a fence set at an angle with a stop to hold the brush. A piece of scrap lumber was placed across to form a triangle and clamped in place. Alignment was done using a drill bit down the central hole already in the handle.
After a test fit I realized that the knot got wider and the original hole diameter would need widening. Drexel to the rescue. I ended up putting a slight bevel on the hole so it would widen just enough for the knot to sit snugly in the hole.
