Had some requests for a classroom thread on turning a coffee mug. Finally getting around to turning some more mugs, so figured I'd document the process and make a thread. Please note, this is only the way I make these. There's probably other ways to do some of these steps, maybe even better ways. But, this is how I do it.
Here's where we're headed:
What you will need:
Mug insert. I use this one as it's the best price I've found. I vastly prefer the screw on lids.
A chunk of wood. 4" x 4" x 8" is what I prefer to start with. I could get away with as small as 3 5/8" x 3 5/8" x 7" if I'm very careful, but I like the little bit extra material to give me some wiggle room to start. I like using both solid wood or laminating pieces together. Some people do stave construction. Others segment rings. I just like the look of the wood in a whole block or laminated blank.
First you'll need to mark the center of each end and then turn the blank round between centers. Make a tenon on the one end to be grabbed with the chuck.
Next, chuck it up and drill it out with a 2 1/8" forstner bit. I use this bit. I have drilled out close to 20 mug blanks with it so far and it's only now to the point where I've decided I'll hit it with the diamond card and sharpen it before I use it again. And that's pure end grain drilling.
If you are using the insert I liked to above from Woodcraft, drill to a depth of 5 3/4".
At this point, if you're using a piece of wood that isn't fully dry, it's time to set it aside until it's dry. How long to dry will depend on species used and your climate and shop space. For me, it takes about 6 to 9 months to dry out a blank in my basement once it's been drilled out and had the end grain sealed. (I usually seal with wood glue thinned with just a touch of water.)
After it's drilled out, I give the outside of the mug a few passes with the tool to get it round, in case it's even a little off from mounting in the chuck. It helps me with my visual perception in the upcoming hollowing step. I also face the front end just drilled into so it's even.
I then measure the exact depth of the hole and make a mark on the outside of the blank where the bottom of the hole is. I make another mark about 5/8" to 3/4" past that to mark where the bottom of the mug will be, so I get a visual when I go to start shaping. You'll notice that I then took these marks and extended them so they go all the way around the blank.
The first line helps with keeping track of where the cutter is on my hollowing rig. Can you manhandle a tool and turn one of these without a hollowing rig. Yeah. I've done it, but I certainly don't recommend it. This is just much safer and easier to hollow with a proper hollowing rig.
The one downside is that my lathe is too short for one. But, not a problem. You can see the solution I came up with to mount it. It works well for me.
Here's why we marked the first mark. It helps you visualize where the bottom of the mug is so you don't go crashing into it with the cutter. The laser on the rig is quite helpful.
Then it's time to hollow. Remove any material from the inside of the blank that keeps you from sliding the insert in all the way. The 2 1/8" bit is the rough diameter of the small end of the insert and the hollowing you do will end up roughly tapered to be wider at the opening than at the bottom. Stop often to check fit. At the top end, I don't want it very tight - I always leave just a little wiggle room to leave some space for the glue that I use to glue in the insert.
After that I hold the insert in and trace around it with a pencil. This gives me a reference point in shaping where, once I reach the pencil line, it's time to be careful with how much material I'm removing and to check the fit of the insert often. You want the lip of the insert to be able to slide down over the wood and have a nice fit all around the outside.
Sometimes I get the insert completely fitted at the top before I do any shaping, as in this pic.
Before I start shaping, I remove some material from the bottom end. This helps me to visualize where the bottom is in shaping and properly shape it.
Here's where we're headed:
What you will need:
Mug insert. I use this one as it's the best price I've found. I vastly prefer the screw on lids.
A chunk of wood. 4" x 4" x 8" is what I prefer to start with. I could get away with as small as 3 5/8" x 3 5/8" x 7" if I'm very careful, but I like the little bit extra material to give me some wiggle room to start. I like using both solid wood or laminating pieces together. Some people do stave construction. Others segment rings. I just like the look of the wood in a whole block or laminated blank.
First you'll need to mark the center of each end and then turn the blank round between centers. Make a tenon on the one end to be grabbed with the chuck.
Next, chuck it up and drill it out with a 2 1/8" forstner bit. I use this bit. I have drilled out close to 20 mug blanks with it so far and it's only now to the point where I've decided I'll hit it with the diamond card and sharpen it before I use it again. And that's pure end grain drilling.
If you are using the insert I liked to above from Woodcraft, drill to a depth of 5 3/4".
At this point, if you're using a piece of wood that isn't fully dry, it's time to set it aside until it's dry. How long to dry will depend on species used and your climate and shop space. For me, it takes about 6 to 9 months to dry out a blank in my basement once it's been drilled out and had the end grain sealed. (I usually seal with wood glue thinned with just a touch of water.)
After it's drilled out, I give the outside of the mug a few passes with the tool to get it round, in case it's even a little off from mounting in the chuck. It helps me with my visual perception in the upcoming hollowing step. I also face the front end just drilled into so it's even.
I then measure the exact depth of the hole and make a mark on the outside of the blank where the bottom of the hole is. I make another mark about 5/8" to 3/4" past that to mark where the bottom of the mug will be, so I get a visual when I go to start shaping. You'll notice that I then took these marks and extended them so they go all the way around the blank.
The first line helps with keeping track of where the cutter is on my hollowing rig. Can you manhandle a tool and turn one of these without a hollowing rig. Yeah. I've done it, but I certainly don't recommend it. This is just much safer and easier to hollow with a proper hollowing rig.
The one downside is that my lathe is too short for one. But, not a problem. You can see the solution I came up with to mount it. It works well for me.
Here's why we marked the first mark. It helps you visualize where the bottom of the mug is so you don't go crashing into it with the cutter. The laser on the rig is quite helpful.
Then it's time to hollow. Remove any material from the inside of the blank that keeps you from sliding the insert in all the way. The 2 1/8" bit is the rough diameter of the small end of the insert and the hollowing you do will end up roughly tapered to be wider at the opening than at the bottom. Stop often to check fit. At the top end, I don't want it very tight - I always leave just a little wiggle room to leave some space for the glue that I use to glue in the insert.
After that I hold the insert in and trace around it with a pencil. This gives me a reference point in shaping where, once I reach the pencil line, it's time to be careful with how much material I'm removing and to check the fit of the insert often. You want the lip of the insert to be able to slide down over the wood and have a nice fit all around the outside.
Sometimes I get the insert completely fitted at the top before I do any shaping, as in this pic.
Before I start shaping, I remove some material from the bottom end. This helps me to visualize where the bottom is in shaping and properly shape it.