Finish turning a bowl

  • by Corin Flood
  • February 10th, 2013

I’ve spent plenty of time looking at wood turning and turners websites, watching turning videos on youtube and the like. The information available to turners now as opposed to when I first turned in the 80′s makes the whole endeavour vastly easier. At least it makes the theory easier, if not the act. The act still requires lots of practice to make it fluid, clean and fast.

So for those turners who might be looking at my website, here’s a bit about how I do it.

I run a Oneway 2436 lathe with a Oneway Easy-Core coring system and Oneway scroll chucks and vacuum chucks.

I rough turn all my production blanks green and use the coring set up to reduce waste and increase the number of useable blanks. I often re-turn green blanks after coring with a gouge so they go to the drying room with clean surfaces and fair curves. This is a bit of an extra step but makes applying end sealer quicker and reduces the re-turning time. The trees that grow around me are generally no bigger than 24″ in diameter which means most of my bowl blanks are centred on the trees core which means they dry symmetrically. They go out of round but usually the difference in diameter is no more than 1/2″. In my part of the world drying without a kiln takes two to three months for birch and maple.

The series below starts with a dry roughed out bowl. The rough bowl is about 13″ in diameter.

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I mount the roughed bowl with the inside against a four jaw chuck, the pressure of the tail stock keeps the blank in place with enough friction to drive it. I’m using a 5/8 Oneway Mastercut gouge with a 60 degree fingernail grind. The gouge is held in a Hosaluk ferrule mounted in a 20″ wooden handle. I like long handles for all my bowl turning, they give more control over the cut whether its fine or course. For this size of bowl I want the lathe to be turning at about 900 rpm once the bowl is balanced. Per the text books, the flute is at 45 degrees, the handle is dropped and the bevel is riding the cut.

To clear the tale stock I use a shearing pull cut at the bottom of the bowl and push cut around the belly and up to the rim. I use a purpose ground scraper to cut the spigot so it matches the dovetail jawed chuck.

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Here the bowl is near final cut. The shine on the bowl is a good indication that the cut is clean. Before sanding the curve of the bowl will be perfectly fair and there will be no tear out. If I don’t plan to sand the outside I use a 1/2″ spindle gouge to make the final cut and add any details such as beads.

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I use the 5/8″ gouge with a finger nail grind to remove the bulk of material from the inside of the rough bowl. The rule of the thumb for re-turning is that the wall thickness for the green bowl should be 10% of the diameter. I can usually do a bit better than this but its a good place to start. Here I’ve switched to a 5/8 Mastercut gouge with a traditional grind and a fine bevel, the wings of the gouge are not swept back. Again the objective is a fair curve and no tear out. At this stage I establish the bottom thickness. I measure the bottom thickness but the rest is by feel.

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Here’s the tricky bit making the transition from the more vertical walls to the flatter bottom. The cutting angle and approach to the cut changes at this point as does the tool. There are a couple of cuts to go to finish the walls here. I often undercut the rim to give it a bit more presence and strength.

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For finishing the bottom I switch to a 3/4″ Glaser Hitec bottoming gouge; this is a fantastic tool and makes finishing the bottom of the bowl a snap. I will finish the transition from side to bottom with this gouge and put the finish cut on the bottom.

There’s lots to keep in mind when turning, much of the movement involved becomes muscle memory with time, but there are a couple things I keep top of mind. First if you think your tool might be dull it is. It is always worth the time to stop and sharpen a tool, it saves time in the end, results in a better finish and a sharp tool is a safe tool. The other thing is speed, there’s no hard and fast rule here, but in my book speed is your friend, the faster the lathe is turning the finer each pass is and the easier it is to achieve a good finish and a fair curve.

(Thanks to my Dad for taking the photo’s!)

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