Introduction: Chucking Scraper for Turning Bowls on Lathe
I have recently decided I was interested in learning how to use a wood lathe. I like old tools, so I went out and found myself an old 4 speed Craftsman Lathe in the back of a barn for $100. After cleaning it, replacing the belt, and getting a cheap set of gouges from Harbor Freight, a good live end tailstock and 4" plate I was good to go. I had a few chairs that needed new spindles and spreaders so I viewed some Instructables and YouTube videos, learned to sharpen my gouges, and got to work learning. Soon I was turning out chair parts and tool handles no problem, but bowls were a different matter. Almost everything I found online talked about using bowl chucks, all of which cost more than my lathe.
Then I found a great article on Woodworker's journal about turning a bowl with just a lathe and a faceplate. That was right up my ally! I was able to use this process with the cheap gouges, but turning an accurate and flat mortise and tenon was tricky. The article mentioned using a Chucking Scraper, so I decided to make one. As I have made hand chisels in the past, so making my own is in my wheelhouse and I figured it would be a good weekend project.
I have decided to divide the video up into 4 parts so you can more easily find the tips and techniques for each section. Hope you enjoy!
Supplies
Handle:
Turning stock, at least 1 1/4" diameter and 16" long. I used a chunk of crepe myrtle because was straight, with clear tight grain, and free
Scraper Blade:
1/2" x 1/4" x 1.5' Oil Hardened Tool Steel (9018K21)
Tools:
Metal can of vegetable oil for quenching steel
Step 1: Tool Length
The first step is to figure out the total length of the tool. The Harbor Freight gouges get the job done, but I think they are a little short. My Dad gave me a nice Wood River roughing gouge for Christmas ("that was a kingly gift") which I really like, so I decided to use that as a model for my tool handle length and shape and my blade length.
Step 2: Forming the Blade
You need to cut your 1/2″-wide by 1/4″-thick tool steel. You will need about 2 1/4" to 2 1/2" for your tang, plus the length of the blade.
Use a scribe to mark out the shape of the tang and tip on the steel.
Take tool steel and grind a 90° angle at the tip. Wear heavy protective gloves, and be sure to stop every few seconds and dip the steel in water so the blade doesn't overheat. You don't want it to get red hot at this point. Roughly grind most of the material for the tang, and use metal files to get it to it's finished shape. I suggest rounding over the sharp corners on the tang to help fit it in the handle.
Step 3: Hardening and Tempering the Blade
I strongly recommend you do this outside on a nice, stable work surface.
After you have the scraper to it's final shape you can harden it. The steel is pretty soft so if you want the end to keep an edge you will need to do this.
I use MAPP gas as it is much hotter than propane, and therefore much faster. I have the BernzOmatic Cutting, Welding, and Brazing Torch Kit that I use for brazing that heats the metal up fast, but it is pricy. Propane will work, it just takes forever.
Hold the blade a few inches from the cutting end using a pair of locking pliers. Heat the cutting end to an orange-red glow, then quickly quench it in a can of vegetable oil. The metal will really heat that oil up, so don't use a plastic or styrofoam cup!
The steel is now hard, but brittle, so you will need to temper the steel. Put it in an oven at 450 degrees for an hour, then let it cool down slowly.
The blade will have soot all over it, but you can clean it up nicely with fine sandpaper and polish it on a buffing wheel if you wish.
Step 4: The Handle
Turn the handle on your lathe based on the length and shape you want.
Step 5: Brass Ferrule
I made a brass ferrule from an old brass fitting I found left in my shop by the previous owner.
Drill a small center hole in the end of the handle (a 1/8" bit will do) for the tailstock on your lathe.
Put your roughly shaped handle on the lathe, and turn a short tenon on the end for the ferrule. Aim for a fit that engages the threads on the brass fitting, and maintain a square shoulder on the tenon to ensure a tight fit with the fitting. You'll need to keep taking the handle off and on the lathe to check the fit.
Once you can thread the fitting on the tenon and it fits tightly, apply a little epoxy to fasten it on permanently.
Once the epoxy is cured, mount the ferrule and handle assembly on your lathe to shape it and finish the handle.
You will need to turn the brass fitting to round. Running the lathe at slow speed, use a coarse metal file to round off the fitting. It helps if you have colored the faces of the fitting with a marker or it is an old dirty fitting to see when it is round. Once round, switch to a finer file or sandpaper (grits 100, 150, 180, 220, 320, 400, 600, etc) to bring the ferrule to final shape and finish.
Step 6: Finish Shaping Your Handle
At this point, get your handle to it's final shape. Taper the end of the handle to be flush with the ferrule. Sand your handle and apply your finish. Personally I like butcher block oil or tung oil for my tools, but wipe on poly will work just as well.
Step 7: Installing the Blade
Drill a 1/4 diameter hole in the end of your handle. Using needle files, shape the hole to fit your tang. The goal is to shape the hole such that when you dry-fit the tang, the shoulders are between 1/2" and 1/4" from the ferrule. Once you get it to dry-fit with that small gap, take the tang out. put some epoxy in the hole, and reinstall the tang, I clamp the scraper blade in a wood vice and tap the handle with a mallet until the shoulders of the tang seat on the ferrule.
Once the epoxy has cured for 5 minutes clean up any squeeze-out with acetone. Allow it to cure overnight before using your scraper.