Help cutting small pot inner lip

[Peter Natale]

Hi All

I was attempting to make a small lidded pot today, and was working on the base. Outside was done and reversed into a chuck, but the inside gave me trouble.

Where I struggled in particular was the inside of the lip, which was intended to be vertical and square. I had removed a bit of the inside and wanted to set the lip so i could reference a wall thickness as I worked my way down.

Using a 1/2" bowl gouge i was scraping / pull cutting with the left wing, flute mostly up and as I came near the lip it catches, rolls hard left and the first broke the rim, and second after shortening the pot snapped the tennon. Game over.

I know why, as it comes to the lip the contact moves off the wing towards the tip and then it is unsupported. The question is how should I cut the lip? Or at least, whats are better options that dont result in half pots in the bin. If I can get a few mm straight i can then shear down.

The ideas I had are:
1. Shear / Push cut, hard to start accurately on the flat surface even on its side and its a loooong reach over the lathe
2. Scraper - which i currently dont have (i use a skew and it isnt nice to the skew)
3. longer, flatter wing so i can stay on the wing and away from the tip

Any guidance would be much appreciated!

Note the wood was old furniture oak 2x4 glued to be a 4x4 mounted cross grain. Its hard as a rock, routinely bends nails. Gouge was not as sharp as it should be (the oak i find blunts tools fast) and the right wing shape has gone weird (not sure why yet) so it shear cuts left better than right, which is partly why i wasn't shear cutting into the pot.

[Pat]

Horizontal skew is the answer you are seeking.

Remove the waste to required depth of the Lip and a couple of millimeters, proud with a spindle gouge. As you may have worked out, some bowl gouges are too aggressive for this task.

Then with tool rest on centre, lay the skew on the rest, held level. Plunge the skew, taking a millimeter at the time. The idea is to sneak up to the desired width and depth. Plunge, stop check will be your mantra.

eg you want a rim of 5 mm thick by 10mm deep, you remove the waste to 10mm and the rim/lip thickness to about 7 or 8 mm.

On a small lidded box, I would use my 12mm skew, this is finesse turning.

[powderpost]

A sketch and size would help to suggest a potential solution. i have been known to make small (50mm) lidded pots.

Jim

[Peter Natale]

Hi

Curves are simplified but this should give the idea. Red is the waste i had left, and the arrow is where i was trying to get to the desired thickness (black line)
522080

[Peter Natale]

@Pat

Thanks!

The approach makes sense. Would a square scraper or half round (bowl scraper) be the same?

In this mode a skew is acting as a negative rake scraper, so in my head it should be the same (and avoid my skew being beaten up). However I am guessing a skew (or negative rake scraper) is probably gentler.

[Picko]

The most important thing here is that you need to be cutting above centre (below centre if you're working on the outside). I would be using a bowl gouge but before I became more proficient with the gouge I would have used an oland style scraper. A negative rake scraper will be more foregiving as you say.

[Pat]

@Pat

Thanks!

The approach makes sense. Would a square scraper or half round (bowl scraper) be the same?

In this mode a skew is acting as a negative rake scraper, so in my head it should be the same (and avoid my skew being beaten up). However I am guessing a skew (or negative rake scraper) is probably gentler.

Hello Peter, the skew will not notice, unless you hit metal DAMHIKT!:B

Finesse is the name of the game for this operation.

You could try with a variety of scrapers, but my experience is that a skew will produce a better result, quicker. Yes you will need to practice the cut, but that is the rule in turning.

[Peter Natale]

@Pat - Thank you!

@Picko - Is that so that the wood is moving (slightly) away from the tool rather than into it? That should make catches less dramatic?

[Picko]

Thats it.