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Forum topic by jumbojack posted 06-16-2016 03:36 PM 1294 views 1 time favorited 23 replies Add to Favorites Watch
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jumbojack

1667 posts in 2090 days


06-16-2016 03:36 PM

It always seem to get these when turning. My tools are sharp. What am I doing wrong?

-- Made in America, with American made tools....Shopsmith


23 replies so far

View Jim Jakosh's profile

Jim Jakosh

17172 posts in 2571 days


#1 posted 06-16-2016 03:57 PM

Hi Jack, I take it you are talking about the chip out. It could be a weak spot in the grain that pulls out when you cut it in a certain direction. I see that happening at school when someone is rounding up a square piece and the cutting of the corner tears down below the surface. I have them cut from the outside inward until it gets round.

What kind of wood is that? Cherry?

Do you get it with just that wood or all types?

Jim

-- Jim Jakosh.....Practical Wood Products...........Learn something new every day!! Variety is the Spice of Life!!

View poospleasures's profile

poospleasures

544 posts in 1950 days


#2 posted 06-16-2016 04:24 PM

That looks like cedar. I really like to turn cedar but it can be a very brittle wood. I would check for loose knots or just hairline cracks. When found dribble some supper glue in them. Like Jim says cut outside to inside. Use very light cuts until blank is round

-- I,ve had amnesia for as long as I can remember. Vernon

View bondogaposis's profile

bondogaposis

4035 posts in 1817 days


#3 posted 06-16-2016 04:25 PM

There is a lot of wonky grain around those knots. It happens to everyone. Best advice is take a real light cut when dealing with wood like that.

-- Bondo Gaposis

View Wildwood's profile

Wildwood

1886 posts in 1600 days


#4 posted 06-16-2016 04:29 PM

+1 on what Bondo had to say.

If talking about the tear out slow down your cut, go back to the grinder for final cuts. You will see a lot of turners using a pull shearing technique with their bowl gouge these days on final cuts. Can do same thing with push cut with practice.

Several Videos online demonstrating how to shear scrap with regular turning & carbide tools.

-- Bill

View JoeinGa's profile

JoeinGa

7483 posts in 1472 days


#5 posted 06-16-2016 05:08 PM

Are you asking about the big chunk missing from the top edge?

Or the heavy turning lines (grooves) on the sides?

-- Perform A Random Act Of Kindness Today ... Pay It Forward

View Jerry's profile

Jerry

1768 posts in 1114 days


#6 posted 06-16-2016 06:45 PM

Jack, I’d love to help, but I suck at turning. This happens to me most often when I’m using a skew chisel. I’ve never mastered that particular tool, and it’s pretty much made turning something I don’t do anymore, scares the crap out of me. If that “turns” out to be your problem, then I guess practicing on more regularly grained wood might get you there. Knots are, well, like stones.

-- There are good ships and there are wood ships, the ships that sail the sea, but the best ships are friendships and may they always be. http://geraldlhunsucker.com/

View Mark Wilson's profile

Mark Wilson

1756 posts in 529 days


#7 posted 06-16-2016 07:50 PM

Yeah. What Joe said. I think you’re talking about the lines – what I call “corkscrews.” I address those with a square-nose scraper, presented with a negative rake. and a very light touch, This happens, as the others said, because the tool you’re using is bouncing over a hard spot – a knot; pitch; heartwood/softwood interchange; etc.
As it happens, I have this on the lathe:

This is glued up Douglas Fir (Eeww). I’ve penciled some of the corkscrews. The thing I try to do with such thing, is to get the shape I’m after, pretty much ignoring the corkscrews til I arrive at the shape, then use, as I said before, a scraper, at a negative angle, very lightly skimming off what I can. Then, when no further progress seems to be taking place, I turn to the heavy-grit sandpaper, to make them go away. This isn’t easy. It takes a lot of patience.
Check this, for more information: http://lumberjocks.com/MLWilson/blog/75194

If you go to the sixth montage down, you’ll see corkscrews on the inside of the bowl. A straight scraper, of course, is no help. You can see the front end of a big round-nose scraper on the tool rest. That’s how I addressed the inside corkscrews. That, and lots of sandpaper.

-- Mark

View Monte Pittman's profile

Monte Pittman

22033 posts in 1804 days


#8 posted 06-16-2016 08:53 PM

I know absolutely nothing about turning. But that looks like Eastern Red Cedar. I believe that it conspires to screw up many projects. Anything with that twisted grain can get you.

-- Mother Nature created it, I just assemble it.

View Lazyman's profile

Lazyman

695 posts in 853 days


#9 posted 06-16-2016 11:10 PM

I’m guessing he’s talking about the big chunk that looks like it has pretty nasty gouge leading up to it? It might help to know what tool you were using when that happened. My worst catches seem to come when I’m not paying close enough attention to where the tip and bevel of the tool is.

I haven’t turned any eastern red cedar, but I have had western red cedar disintegrate with the smallest of catches. Fortunately, I was just using it to experiment with with different tools so it was better than getting a bad catch on something that didn’t give.

-- Nathan, TX -- Hire the lazy man. He may not do as much work but that's because he will find a better way.

View jumbojack's profile

jumbojack

1667 posts in 2090 days


#10 posted 06-17-2016 12:57 AM

Thanks guys. It is cedar I milled several years ago. Catches such as this:

and this

I get this type of thing more often than not.
I rarely turn but seeing all the cool stuff you guys do, I’m trying but failing. Kinda spooky when it grabs as well.

-- Made in America, with American made tools....Shopsmith

View Kelly's profile

Kelly

1113 posts in 2410 days


#11 posted 06-17-2016 01:24 AM

I’m a turner newbie too, but I like turning cedar. It makes for some nice product, then done.

I haven’t tackled any with a skew. I use gouges I keep sharp and a light touch on my back hand. That lets the knife bounce, if it must, and reduces forcing it to do what the wood refuses to let it do (guess that qualifies as a catch).

When I get something like this, it’s always been a fracture or something and in dry wood, which is what I mostly turn.

View jumbojack's profile

jumbojack

1667 posts in 2090 days


#12 posted 06-17-2016 02:06 AM

A light grip on the handle, eh? I usually have a death grip on the handle, white knuckle death grip.

-- Made in America, with American made tools....Shopsmith

View jumbojack's profile

jumbojack

1667 posts in 2090 days


#13 posted 06-17-2016 02:08 AM

Oh I was using a roughing gouge. Sharp enough to slice paper or shave hair on my arm.

-- Made in America, with American made tools....Shopsmith

View TheDane's profile

TheDane

4997 posts in 3129 days


#14 posted 06-17-2016 03:20 AM

Roughing gouge … as in ’Spindle Roughing Gouge’?

That’s the wrong tool to be using on a cross-grain piece. Do you have a bowl gouge?

-- Gerry -- "I don't plan to ever really grow up ... I'm just going to learn how to act in public!"

View jumbojack's profile

jumbojack

1667 posts in 2090 days


#15 posted 06-17-2016 05:05 AM

Yes a spindle gouge. I don’t have a bowl gouge. Guess I start looking.

-- Made in America, with American made tools....Shopsmith

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