Turning and tear-out
Turning and tear-out
When you cut on the lathe, if you are using a scraper, most types of cutter on a metal lathe, or a gouge "head on" you'll find that it's easy enough to cut the shape you want, but the tool will rip out a lot of little chunks, and particularly on a cross-cut block, it will be the end-grain pointed into the cut which will tear out. You can sand this stuff out, but it takes a long time and it's unnecessary.
Here's two pictures, same tool, applied at different angles.
Head on with a gouge:
And cut with a "skew" angle, same gouge. A skew chisel will offer the same result but it's a lot harder to master.
You can actually see the previous tearout at the top of the stummel in this picture more clearly than in the last - I'll have to make another pass to get all the previous damage erased.
But I'm already at a point where if I hit this with 320 paper, I'm going to be going backwards in terms of shine. (A good thing in this case - stain is not going to work well on the piece as is).
So there you go - that's the difference between turning a shape and sort of managing it, and cutting a shape properly. Done right, you can pretty much make your cut and walk away, which is why "proper" turners use skew chisels and gouges, and really no scrapers at all.
Here's two pictures, same tool, applied at different angles.
Head on with a gouge:
And cut with a "skew" angle, same gouge. A skew chisel will offer the same result but it's a lot harder to master.
You can actually see the previous tearout at the top of the stummel in this picture more clearly than in the last - I'll have to make another pass to get all the previous damage erased.
But I'm already at a point where if I hit this with 320 paper, I'm going to be going backwards in terms of shine. (A good thing in this case - stain is not going to work well on the piece as is).
So there you go - that's the difference between turning a shape and sort of managing it, and cutting a shape properly. Done right, you can pretty much make your cut and walk away, which is why "proper" turners use skew chisels and gouges, and really no scrapers at all.
ALL YOUR PIPE ARE BELONG TO US!
- archaggelosmichail
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Re: Turning and tear-out
I use only the parting tool to shape my pipes on the lathe, from top to bottom.If ther is any "fine" line on the shape I use the fingernail to get it right.
If there is any tear out, 80,120 and finally 180 sandpaper will get them of in 2 min.
If there is any tear out, 80,120 and finally 180 sandpaper will get them of in 2 min.
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Re: Turning and tear-out
I don't have a two jaw chuck OR a set of gouges chisels and Sasquatch toenails, so I don't have this issue.
Re: Turning and tear-out
Some really valid points. Keep 'em coming lads.
ALL YOUR PIPE ARE BELONG TO US!
Re: Turning and tear-out
Whatever I use to turn, I make sure it's sharp, sharp, sharp! I regrind and sharpen at least once every few pipes, and I touch up the edges before every pipe with some Eze-Lap hones http://www.artcotools.com/eze-lap-diamond-hones.html
Cheers!
-Walt
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"I have no idea what's going on here. " - Ernie Markle
-Walt
http://waltcannoy.com
http://www.facebook.com/WaltCannoyPipes
http://www.youtube.com/user/wcannoy
http://instagram.com/waltcannoy
http://twitter.com/WCannoy
"I have no idea what's going on here. " - Ernie Markle
Re: Turning and tear-out
I have learned (the hard way) that if you follow these tips you can eliminate end grain tear out.
1) Keep your tools not just sharp, but scary sharp.
2) Learn to ride the bevel of your tools.
3) Sharpen before your final pass and take only a very light cut.
Todd
1) Keep your tools not just sharp, but scary sharp.
2) Learn to ride the bevel of your tools.
3) Sharpen before your final pass and take only a very light cut.
Todd
Re: Turning and tear-out
Never thought I'd hear Sas call himself "proper."
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Re: Turning and tear-out
Right? It's about like me calling myself a lady
Am I Calamity Jane or Annie Oakley??...depends on the day.
www.ladybriar.com
www.ladybriar.com
Re: Turning and tear-out
Nonono - I said merely that proper turners prefer skews and gouges. I use my toenails - just like Yeti.
ALL YOUR PIPE ARE BELONG TO US!
Re: Turning and tear-out
is it possible to cut briar turning on a metal lathe with wood lathe cutting tools? it seems like it should be possible but I honestly haven never messed with a metal lathe much
Re: Turning and tear-out
BigCasino wrote:is it possible to cut briar turning on a metal lathe with wood lathe cutting tools? it seems like it should be possible but I honestly haven never messed with a metal lathe much
I use wood turning tools with my metal lathe all the time. I like the precision of the tool bits for shanks and stems, but I usually use wood turning tools for the bowls. It's worked fine for me so far.
Re: Turning and tear-out
Certainly you can, certainly there's times it's advantageous - you just need a plain tool rest to do so.
ALL YOUR PIPE ARE BELONG TO US!