Hollowing, especially end grain timbers can be a challenge. Entering through a small, 1” or less, diameter hole makes using a bowl gouge nearly impossible. Handheld hollowing tools are better but still put a lot of stress on the user. I designed and built this articulating hollowing tool to overcome the short comings of traditional and even other specialized hollowing tools on the market.
The criteria for this project were simple. It needed to work, easy to use, and be cheap and easy to build. For simplicity in building, I designed this project around two pivoting points and is held in the back by the tailstock. This only required me to make a few cuts and drill a few holes. The cost of the project was inherently low. It only takes a few bearings and a small amount of steel.
(6) 3/8” od x ¼” id bearings
1”x1” square structural steel
¼”x 1” flat structural steel
5/8” round steel
½” round steel
¼” round steel
(5) ¼” bolts
1 thumb screw
1 set screw
Paint and Primer
Pen Laser- Can be purchased HERE
¼” round tool steel
Using ¼” bolts, I sandwich part “A” between the 2 “B” parts and bolt tightly using the two holes towards the right side of the above picture.
Next I cut part “C” from an 8” length of 1x1 square stock. Then I drilled both ends as shown below. I start with a shallow hole 3/8” diameter. This is a rest for the bearings. Drill the depth to allow about 1/32” of the top of the bearing to protrude from the surface of the 1” square stock. This will allow clearance when the tool is in motion. Next drill the ¼” diameter through holes in each end.
Adding the laser attatchment.
This is not necessary but makes this tool extremely user friendly.
First, cut a length of ¼ round steel to a length of between 8” and 12” labeled “H” below. For simplicity, this can be glued into the hole on part “F”. Or, another set screw or thumb screw can be used to secure the round stock to part “F” as shown.
Adjust part “K” until the laser strikes the tip of the tool bit.
Using the Hollowing Tool
Before the tool will cut, the tip needs to be ground and sharpened. There are many shapes that the bit(s) can be ground. Find what works for you and sharpen the tool often. This is a scraping tool and needs to be sharp.
Grip your work piece in a 4 jaw chuck. Bring your tool rest as close to the work piece as possible and at 90 degrees to the long axis of your weighs. Insert the Jacobs chuck into your tailstock. Rest the tool bit holder onto the tool rest and insert part “G” into the Jacobs chuck and tighten down. Adjust the height of the tool rest so that the tool tip is cutting at the center line of the piece. Start the lathe and lightly plunge the tip into the center of the work. Gradually increase the diameter of the hole to approximately 1”. Slowly work deeper into the vessel stopping often to clean out the chips.
Please remember to see my Turning Supplies section HERE for great prices on many woodurning supplies.