Floating base
- Thread starter AlanLevin
- Start date
Ken Sherwin
PRO Member
I don't know what he said about it but I need 3 parts when I make a floating base. The important part is the center disk. I start by planing the material to my chosen thickness, bandsaw a rough circle a bit bigger than I need, and turn the OD to the diameter I want. To hold it, I use a technique called pressure turning where I put a waste block in a chuck and face the end flat to give me a working surface. I force the workpiece against that work surface with a live center in the tailstock using plenty of pressure. That clamping pressure is what holds the workpiece while I gently turn the OD to the chosen diameter.
The next piece I need is the bottom ring that has a rabbet turned on the ID that is large enough to hold the disk both in diameter and thickness.
The last piece I need is the second ring whose ID is turned round but still small enough to capture the loose disk. The face that mates to ring 1 is flat.
To assemble this thing, I drop the disk in the bottom ring and holy it there with three small dots of silicone rubber that I let cure ahead of time. These hold the disk centered in the rabbet so it can shrink and swell as it wishes. I then glue ring 2 to ring 1 being careful with the amount of glue I use. and where I put it. I glued the disk to the rings the first time I tried it!
Does this help?
The next piece I need is the bottom ring that has a rabbet turned on the ID that is large enough to hold the disk both in diameter and thickness.
The last piece I need is the second ring whose ID is turned round but still small enough to capture the loose disk. The face that mates to ring 1 is flat.
To assemble this thing, I drop the disk in the bottom ring and holy it there with three small dots of silicone rubber that I let cure ahead of time. These hold the disk centered in the rabbet so it can shrink and swell as it wishes. I then glue ring 2 to ring 1 being careful with the amount of glue I use. and where I put it. I glued the disk to the rings the first time I tried it!
Does this help?
I like the description of making the floating disk,thanks for that.
If you still have a solid base disc does that that still have a risk to crack?
Ken Sherwin
PRO Member
The largest base I've done was about 6" OD, 3/4" thick solid walnut and it hasn't cracked. If you think about it, a chunk of wood that small isn't really going to change size all that much but I guess there's always a risk to get a wonky stick. I've done a few floating bases just for the fun of it, not because I was convinced of its necessity.
I have many bows with a solid base that are over 10 years old and the vessel has not cracked.
imo, some factors that play in a solid base vessel cracking are"
- humidity change (moving a vessel from a dry climate to a high humidity climate (or reverse)
- having a solid disk base larger than 5 or 6 inch in diameter
using wood that is very stable (like mesquite) reduces the risk.