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View Full Version : What I learnt from Groggys Turnon. Sharpening.



tea lady
2nd Feb 2010, 10:06 PM
this is taken care for on days like Brendan Stemp is running at Horsham ,You
Turn ,first weekend in May. :)
Take your lathe and work on project,ask and see what other people are making.
Regards
David:2tsup:But I've got a Tough lathe. And no forklift.:C

Anyway, I think its OK that there is a variety of types of turnfest. At some you just watch and heckle. Some you bring your own lathe and can get some help with projects as you go. (There is less heckling when most people are busy.:rolleyes: ) What they all have in common is meeting people, and the conversations over tea or the BBQ. ......... Oh! And the choccy ripple cake.:D

My take away tip from this turnfest is to not use the scraper as the last tool when turning a bowl, thinking that you are smoothing out the form. It creates the most tear out of any tool which takes a long time to sand out. If you can do the "finishing cut" using the bowl gouge (Using it in the sheer scraping mode if possible, ) although it seems to leave a slightly ridged surface, there is minimal tear out and the ridges sand out very easily. (With one or two passes of 120# rather than ages with the "60# gouge".:doh: )

rsser
3rd Feb 2010, 04:53 PM
One of my take-outs was to see how laid the bowl gouge off-side to do the 'corner' and bottom. He'd posted on this b4 and I'd had a play but it was good to see clearly how it was done.

By way of another take on reducing tear-out in a bowl, have a browse thru here on Michael Mouse who uses a continental or possibly forged spindle gouge, presented cutting edge near vertical: click (http://www.aawforum.org/vbforum/forumdisplay.php?f=2)

tea lady
3rd Feb 2010, 05:08 PM
One of my take-outs was to see how laid the bowl gouge off-side to do the 'corner' and bottom. He'd posted on this b4 and I'd had a play but it was good to see clearly how it was done. Yes! You gotta see things sometimes. Word are an imperfect science. :U

By way of another take on reducing tear-out in a bowl, have a browse thru here on Michael Mouse who uses a continental or possibly forged spindle gouge, presented cutting edge near vertical: click (http://www.aawforum.org/vbforum/forumdisplay.php?f=2)Can't find the post . Link only goes to list of posts. Anyway, sounds like he's doing a kinda sheer scraping thing too. :think:

rsser
3rd Feb 2010, 05:09 PM
And to add ...

When Ken said that after sharpening you'll get metal flakes in your bowl inside, I agree, when you've done it on a Tormek ( you know, one of those over-priced machines designed and made in Sweden for knife sharpening). You can break the flakes off with your thumb.

I've never seen them in the bowl after dry grinding.

And Farrance's pioneering test of the two systems found that dry grinding produced a hard burr that couldn't fully be removed even with some honing.

rsser
3rd Feb 2010, 05:11 PM
TL, I said 'browse'.

And it's not shear scraping.

RETIRED
3rd Feb 2010, 06:32 PM
This may interest some.

http://www.morewoodturning.net/articles/sharpen.pdf

tea lady
3rd Feb 2010, 11:31 PM
TL, I said 'browse'.

And it's not shear scraping.:rolleyes: OK OK! I'll browse.:D (That word just looks wrong doesn't it? :think: )

I can't "search" cos I'm not a registered member. You can't find the actual post for me can you Ern? :d

rsser
4th Feb 2010, 07:51 AM
Here ya go ... clicky (http://www.aawforum.org/vbforum/showthread.php?t=6623&highlight=gouge)

rsser
4th Feb 2010, 03:43 PM
This may interest some.

http://www.morewoodturning.net/articles/sharpen.pdf

Good call .

Lot of Lyn's stuff on that site bears study.

tea lady
4th Feb 2010, 04:45 PM
Here ya go ... clicky (http://www.aawforum.org/vbforum/showthread.php?t=6623&highlight=gouge)

Thanks Ern. :2tsup:

:think: Still looks like sheer scraping to me. :shrug: A spindle gouge can be used on a shallow bowl or platter. Ya just need the deeper fluted bowl gouges to get the right cutting angles in the deeper bowls.:)

rsser
4th Feb 2010, 05:19 PM
Well, the vids show already shaped bowls on which he's doing finishing cuts.

The bowls are open forms. Diff story with semi-enclosed forms.

If you think they're scraping cuts then one of us needs new specs.

tea lady
5th Feb 2010, 05:43 PM
:cl: OK! Specs on! He's using a traditional gouge. Turned a bowl last night and 'speramented. I can't use a gouge like that cos the lathe bed is in the way. I think the swept back bowl gouge was developed for just such an occasion. Kinda the same profile as a traditional gouge on the wings but the handle is in a different direction. :cool: This means the lathe doesn't get in the way. Also means 1 tool does at least 2 things. Trad gouge wouldn't be able to be used on very deep bowls though.:)

rsser
5th Feb 2010, 05:59 PM
Onya TL.

His gouge looks to me to be fine on outsides, and open form insides.

But I can't see why yr bed is getting in the way.

Raise the toolrest?

tea lady
5th Feb 2010, 06:27 PM
Onya TL.

His gouge looks to me to be fine on outsides, and open form insides.

But I can't see why yr bed is getting in the way.

Raise the toolrest?

I'll take some pics tonight. (It was a little hard seeing what angles MMouse was actually using.:doh: )

rsser
6th Feb 2010, 05:23 AM
Yeah; chk out all his vids.

Cutting edge seems close to vertical to me.

tea lady
7th Feb 2010, 12:25 AM
Yeah; chk out all his vids.

Cutting edge seems close to vertical to me.:think: But how does he then get bevel support AND have the chisel so horizontal? :think: I had to have mine at 45 angled down at least. :shrug: Hence the lathe bed in the way. :doh:

RETIRED
7th Feb 2010, 08:54 AM
Bring your camera, bowl and chisel to work. We will have a play and I show you.:cool:

tea lady
7th Feb 2010, 12:04 PM
Bring your camera, bowl and chisel to work. We will have a play and I show you.:cool::cool::2tsup:

brendan stemp
8th Feb 2010, 08:23 AM
But I've got a Tough lathe. And no forklift.:C

My take away tip from this turnfest is to not use the scraper as the last tool when turning a bowl, thinking that you are smoothing out the form. It creates the most tear out of any tool which takes a long time to sand out. If you can do the "finishing cut" using the bowl gouge (Using it in the sheer scraping mode if possible, ) although it seems to leave a slightly ridged surface, there is minimal tear out and the ridges sand out very easily. (With one or two passes of 120# rather than ages with the "60# gouge".:doh: )

I wouldn't disagree with this but have to add that we shouldn't apply a 'one size fits all' approach to woodturning. My woodturning life changed for the better when I discovered scraping as a means of finishing, especially with the likes of red gum and buloke. However, when I tried this technique on some NZ timbers I found it just didn't work very well so I had to resort to finishing with a bowl gouge. I think the point is we need to know our timbers and which will take scraping and which ones wont.

One other point, if you are going to use a bowl gouge to shear scrape why not use a scraper for the same job. A lot easier IMHO.

rsser
8th Feb 2010, 09:25 AM
Yeah, on a blue moon I can get a line inside a bowl that doesn't need help from a scraper.

More often on the outside.

As Brendan says ... some timbers respond better than others. With a recent Deodar batch cutting was better with some parts of the grain and worse with other parts, on the outside. Scraping reversed that oddly enough and on average required the same amount of sanding.

As posted elsewhere, it's worth playing around with a scraper that's had the burr lapped off, depending on the timber. by contrast, hollowing end grain in a straight sided form say in redgum, I prefer the biggest burr poss on a square-ended scraper, and it's obvious when the burr is worn off - dust instead of fluff.

tea lady
8th Feb 2010, 09:43 AM
:think: True. Different woods and grains need different approaches. :cool:

brendan stemp
8th Feb 2010, 12:52 PM
Yeah, on a blue moon I can get a line inside a bowl that doesn't need help from a scraper.



We had two blue moons in December and I think another two in Feb or March.

tea lady
8th Feb 2010, 01:02 PM
We had two blue moons in December and I think another two in Feb or March.Cool! I'd better get my blanks prepared then!
http://cdn.woodworkforums.com/images/smilies/standard/biggrin.gif

Took some pics of doing outside of a bowl this morning. But can't muck about with 'em till tomorrow. So you'll all have to be patient.:cool:

brendan stemp
8th Feb 2010, 01:10 PM
Cool! I'd better get my blanks prepared then!
http://cdn.woodworkforums.com/http://cdn.woodworkforums.com/images/smilies/standard/biggrin.gif


Turning by moonlight TL? Could be the new craze!

Tim the Timber Turner
8th Feb 2010, 02:17 PM
I agree with Brendan on the issue of scrapers.

I work some very hard and dense desert timbers and scrapers just about always give a better surface finish.

When using a gouge on these hard timbers I find I have to lean on the gouge fairly hard to get it cutting. With the increased pressure required, tool control declines.

However with a sharp scraper the very precise tool control is not hard to achieve.

Two of the things to consider in the scraping v cutting argument are
1: efficent wood removal
2: quality of the finished surface.

Different timbers give different results.

Or you could say "whatever rows your boat".

My first woodturning teacher was an old production spindle turner and his golden rule was "Thou shalt not scrape".

For a long time I felt guilty every time I picked up a scraper.

I'm over it now but it took time.

Cheers

Tim:)

RETIRED
8th Feb 2010, 02:28 PM
I agree with Brendan on the issue of scrapers.

I work some very hard and dense desert timbers and scrapers just about always give a better surface finish.

When using a gouge on these hard timbers I find I have to lean on the gouge fairly hard to get it cutting. With the increased pressure required, tool control declines.

However with a sharp scraper the very precise tool control is not hard to achieve.

Two of the things to consider in the scraping v cutting argument are
1: efficent wood removal
2: quality of the finished surface.

Different timbers give different results.

Or you could say "whatever rows your boat".

My first woodturning teacher was an old production spindle turner and his golden rule was "Thou shalt not scrape".

For a long time I felt guilty every time I picked up a scraper.

I'm over it now but it took time.

Cheers

Tim:)Are you sure?:wink:

rsser
8th Feb 2010, 06:18 PM
heheh; I'm still not over the HS WW teacher's advice not to put the handplane sole-down on the bench. I do it, with iron retracted, but still twitch :-

FWIW, looking at my rough-out of ancient Kauri that's now dry, Terry Scott of NZ kindly gave some advice on finishing it. Mostly, it was DON'T TOUCH IT WITH A SCRAPER. It will pull the fibres out big-time.

Tim the Timber Turner
8th Feb 2010, 06:41 PM
Are you sure?:wink:

I think so :;

I have managed to turn a few bowls since but was never much chop at them spindle thingys:wink:

Please stop winking at me, my wife might look over my shoulder.

Cheers

rsser
8th Feb 2010, 07:42 PM
Just show her the pics from Groggy's turn-on thread Tim and you'll be safe ;-}

tea lady
8th Feb 2010, 11:46 PM
Just show her the pics from Groggy's turn-on thread Tim and you'll be safe ;-}I think I'm only in the back of one of them, so she'll think there are only reprobates there.:D:run:

rsser
9th Feb 2010, 03:15 PM
Just came across a useful tip in one of your give-away mags TL:

If you want a big burr on a scraper, grind it upside down.

....

One take-out for me from the day was how quickly Calm bored the hole in his pepper grinder with an auger. Quicker than my efforts with a saw-tooth bit.

NeilS
9th Feb 2010, 05:56 PM
One other point, if you are going to use a bowl gouge to shear scrape why not use a scraper for the same job. A lot easier IMHO.



Agreed, Brendan, purpose made tools tend to do a better job.

However, one possible reason is that those long swept back wings on a gouge with an Ellsworth/Irish grind rarely get used but are constantly sharpened. So, why not get some value from all of that that good HSS steel while it's sharp and ready to use. And, the tool is already in your hand ready to go!

Not that I do so myself .... :U... much prefer to use my scrapers. But those long gouge wings do a nice last shear cut whether or not scraping is required.

.....

Manuka Jock
9th Feb 2010, 06:02 PM
We had two blue moons in December and I think another two in Feb or March.
Making a total of three a month ? No chance :U
Two at most
" Recent popular usage defined a blue moon as the second full moon in a calendar month, stemming from an interpretation error made in 1946 that was discovered in 1999 <SUP id=cite_ref-SkyTel_0-1 class=reference>[1] (http://www.woodworkforums.com/#cite_note-SkyTel-0)</SUP>. For example, December 31, 2009 was a blue moon according to this usage."

Blue moon - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Blue_moon#Visibly_blue_moon)

Manuka Jock
9th Feb 2010, 06:11 PM
heheh; I'm still not over the HS WW teacher's advice not to put the handplane sole-down on the bench. I do it, with iron retracted, but still twitch :-

FWIW, looking at my rough-out of ancient Kauri that's now dry, Terry Scott of NZ kindly gave some advice on finishing it. Mostly, it was DON'T TOUCH IT WITH A SCRAPER. It will pull the fibres out big-time.

True , use the rotary grit scrapers , they work just fine on kauri :2tsup:.

I sit the toe , or the heel , of the plane up on something , that way the handle is always graspable.

NeilS
9th Feb 2010, 06:48 PM
If you want a big burr on a scraper, grind it upside down.



Would a wet grinder with its rotation going away from the tool do the same thing or does the cool grind not throw up much of a burr?

.....

tea lady
9th Feb 2010, 08:40 PM
Turned the outside of a bowl on Monday to try a few different gouges at different angles. I took the pics with the lathe off cos I've only got two hands. But they at least show the angles that the gouges were used at.:cool:

Continental gouge scraping?
129250

Continental gouge cutting. (With beval support. )
129251

Bowl gouge cutting. (Direction of cut away from foot ring. )
129252

Bowl gouge "sheer scraping". (Direction of cut away from foot ring also. )
129253

I liked the finish I got off the continental gouge so I finished the whole bottom of the bowl. Here are the resulting lines all over the place. According the Ken these sand out really easily. :C
129254129255

:2tsup::cool: Whadaya know! Ken is right. After a few licks of 120# paper it looked pretty b*^$% good. :cool:
129256

Here is some tear out left just for research purposes. :C Not so easy to eradicate. :doh: Even on this soft cedar.:rolleyes:
129257

So there ya go. Everyone now has to race out and get continental or traditional gouges.:cool: And don't scrape. Cedar anyway. Next I should try a bit of burl. Just for research.:D Anyone got any? :whistling: (Its OK! I've got some lurking there somewhere.:D )

brendan stemp
9th Feb 2010, 09:49 PM
....

One take-out for me from the day was how quickly Calm bored the hole in his pepper grinder with an auger. Quicker than my efforts with a saw-tooth bit.

Auger bits are definitely the way to go for grinders. Main reason because they clear the swarf so efficiently preventing the bit getting stuck in the hole. I use mine so much I had a 2MT braised onto the end.

brendan stemp
9th Feb 2010, 09:50 PM
Making a total of three a month ? No chance :U
Two at most
" Recent popular usage defined a blue moon as the second full moon in a calendar month, stemming from an interpretation error made in 1946 that was discovered in 1999 <sup id="cite_ref-SkyTel_0-1" class="reference">[1] (http://www.woodworkforums.com/#cite_note-SkyTel-0)</sup>. For example, December 31, 2009 was a blue moon according to this usage."

Blue moon - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Blue_moon#Visibly_blue_moon)

Ah yes, you got me there. But you know what I mean?

jefferson
9th Feb 2010, 11:10 PM
Tea Lady,

pic 4 I think you said was shear scraping with the gouge. Not so. IMHO.

The flute nearly needs to be turned over such that the inside flute is close to 45 degrees, almost closed, cutting, not scraping.

Can one of the experts post of pic of how it should be done? Jim C. had me doing it the right way (right-handed I might add) over Xmas-New Year. Safe as houses.

If you are doing it correctly, you can barely see the flute open. Chisel handle low, pulling the tool toward you with the cut. Tiny, tiny cuts.

And Brendan, I must admit some confusion with your post. I've got more scrapers than most on the board at last count. Tormek sharp, some with radical grinds. None work as well (at least on fiddleback redgum or blackwood) as the HT Ellsworth in the right hands.

I took some convincing, but what Ken W and Jim C proved to me is that true shear "scraping" kills tear-out. It can take some time to correct poor tool work, but my limited knowledge of tool geometry insists that the HT gouge works better than all my fancy scrapers.

IMHO.

No doubt I will be taken to the cleaners in the morning and educated some more...... :D:D:D

tea lady
9th Feb 2010, 11:23 PM
Tea Lady,

pic 4 I think you said was shear scraping with the gouge. Not so. IMHO.

:think: Well, the Wielder today was telling me that for it to be sheer scraping it had to have bevel support. :shrug: I have done it turned over like you discribe. But I reckon it makes more tear out than anything else. ::C (Have you tried my "twin blade razor" scraping? BOTH edges are touching.:cool: Twice as much tear out. :doh: But its fun.:rolleyes::D )

All will be sorted tomorrow. (:rolleyes: Anyone know how to get the lid back onto cans o' worms? :C:D)

jefferson
10th Feb 2010, 12:06 AM
:think:

All will be sorted tomorrow. (:rolleyes: Anyone know how to get the lid back onto cans o' worms? :C:D)

Can't help with that one, so sorry. I'll leave it to the bigger boys. :)

RETIRED
10th Feb 2010, 07:30 AM
:think: Well, the Wielder today was telling me that for it to be sheer scraping it had to have bevel support. :shrug: I have done it turned over like you discribe. But I reckon it makes more tear out than anything else. ::C (Have you tried my "twin blade razor" scraping? BOTH edges are touching.:cool: Twice as much tear out. :doh: But its fun.:rolleyes::D )

All will be sorted tomorrow. (:rolleyes: Anyone know how to get the lid back onto cans o' worms? :C:D)NO, no. The definition of scraping is that it has NO bevel support.

rsser
10th Feb 2010, 07:46 AM
Would a wet grinder with its rotation going away from the tool do the same thing or does the cool grind not throw up much of a burr?
.....

Std pos'n Neil is wheel turning away from the edge. With gouges you get a flaky 'burr' that can almost be pushed off with a finger. Haven't tried a scraper.

tea lady
10th Feb 2010, 07:48 AM
NO, no. The definition of scraping is that it has NO bevel support.:C But what about "sheer scraping"?:?

:think: So pick 1 shows scraping? But with edge of tool at a nearly vertical angle to the rotation of the piece?

brendan stemp
10th Feb 2010, 08:50 AM
And Brendan, I must admit some confusion with your post. I've got more scrapers than most on the board at last count. Tormek sharp, some with radical grinds. None work as well (at least on fiddleback redgum or blackwood) as the HT Ellsworth in the right hands.
...... :D:D:D

What is common to all woodturning chisels is the fact they have a sharp (hopefully) cutting edge. So, present this sharp cutting edge to the rotating wood and it will cut, scrape or shear scrape no matter what the shape of the tool is but depending on how it is presented to the rotating wood. It don't matter whether it is a HT Ellsworth grind or any other tool or grind, it still has a sharp cutting edge and if you present that cutting edge to the wood the same as any other cutting edge (no matter what shaped tool, or flute or size or brand or whatever) it will have the same result. A scraper is only a scraper if you use it in a scraping manner. I use my skew chisel as a scraper and a shear scraper and occasionally as a cutter/slicer, but the fact is it is still called a skew chisel. So when is a skew chisel a skew chisel? I bought a square nosed scraper and ground it into a skew chisel profile so what is it? A scraper or a skew chisel? The answer: it just doesn't matter! It's what is done with them that does matter. But giving them names tends to suggest a way the tool must be used and while this keeps the traditionalists happy it tends to confuse the issue. Back to my first point: all tools have a cutting edge and it is a matter of how it is presented to the rotating wood that determines whether it is a shear scrape, a scrape or a cut/slice.

Interesting to note Cindy Drozda (at last years Turnfest) was calling her skew chisel a 'negative rake scraper'. A bit of tongue in cheek, I think.

That's my lecture for the week, sorry about the rant.

Tim the Timber Turner
10th Feb 2010, 09:11 AM
Spot on Brendan.

Better than I could have explained it.

Too much nonsense about about angles, bevels ect.

Just go and turn some wood.

Some days I have a skew chisel and some days it's a pointy nose scraper.

Depends on what I want it to do.

Cheers

Tim:)

rsser
10th Feb 2010, 09:56 AM
And if you burnish a 'hook' on a 'scraper' you have a cutting tool, at least acc to Veritas!

Manuka Jock
10th Feb 2010, 02:53 PM
I've seen Soren Berger turn with a screwdriver , and heard of a demo he did with a sharpened spoon :)

rsser
10th Feb 2010, 03:07 PM
LOL.

yeah, whatever works.

OTOH he makes a neat end-grain hollowing tool that is some distance from a spoon.

Aussies can source it from Jim Carroll now :2tsup:

RETIRED
10th Feb 2010, 03:45 PM
What is common to all woodturning chisels is the fact they have a sharp (hopefully) cutting edge. Agreed.
So, present this sharp cutting edge to the rotating wood and it will cut, scrape or shear scrape no matter what the shape of the tool is but depending on how it is presented to the rotating wood. Agreed.
It don't matter whether it is a HT Ellsworth grind or any other tool or grind, it still has a sharp cutting edge and if you present that cutting edge to the wood the same as any other cutting edge (no matter what shaped tool, or flute or size or brand or whatever) it will have the same result. Not necessarily so. A traditional shaped gouge (thumbnail) cuts completely different to a skew cuts completely different to a bowl gouge cuts completely different than an Ellsworth. They have to be presented to the work in different ways in order to get them to cut cleanly. This is why beginners have trouble when using different tools.

A scraper is only a scraper if you use it in a scraping manner. Agreed.

I use my skew chisel as a scraper and a shear scraper and occasionally as a cutter/slicer, but the fact is it is still called a skew chisel. Agreed.

So when is a skew chisel a skew chisel? A skew chisel is a skew chisel when a rectangular bar is ground askew.

I bought a square nosed scraper and ground it into a skew chisel profile so what is it? A straight across ground chisel.

A scraper or a skew chisel? It can be used as both depending on which way it is presented to the work.

The answer: it just doesn't matter! It does matter if you are trying to tell someone that you are scraping, cutting or peeling.

It's what is done with them that does matter. Agreed, but you still have to know the difference.

But giving them names tends to suggest a way the tool must be used not so and while this keeps the traditionalists happy it tends to confuse the issue. I don't think so.

Most of us have more than 8-9 chisels.

If I said to someone go get me a chisel they would not know what to get.

Hence names are a good thing but manufacturers and demonstrators change names to suit themselves and become common usage.

Back to my first point: all tools have a cutting edge and it is a matter of how it is presented to the rotating wood that determines whether it is a shear scrape, a scrape or a cut/slice. Agreed.

Interesting to note Cindy Drozda (at last years Turnfest) was calling her skew chisel a 'negative rake scraper'. A bit of tongue in cheek, I think. Don't think it was.

That's my lecture for the week, sorry about the rant.Forgive mine?Woodturning is one of the oldest wood machining trades on the planet.
The names of tools are put there for identification purposes so that most people know what you are on about otherwise nobody would have the knowledge they have today.

Every trade has names for tools that don't suggest what they are used for but to a person in the know it identifies which tool to use.

rsser
10th Feb 2010, 04:19 PM
I bought a square nosed scraper and ground it into a skew chisel profile so what is it? A straight across ground chisel.

There was a muddle IMO about this at 's sharpening day.

Square skew was mentioned; Irish logic.

You don't see them much but there's a square ended turning chisel with 2x bevel. A wide beading/parting tool if you like. Sounds like what is talking about.

Diag in plan from the HT site

Time for a cuppa tea and a Bex!

KenW
10th Feb 2010, 04:29 PM
Turned the outside of a bowl on Monday to try a few different gouges at different angles. I took the pics with the lathe off cos I've only got two hands. But they at least show the angles that the gouges were used at.:cool:

Continental gouge scraping?
129250

Continental gouge cutting. (With beval support. )
129251

Bowl gouge cutting. (Direction of cut away from foot ring. )
129252

Bowl gouge "sheer scraping". (Direction of cut away from foot ring also. )
129253

I liked the finish I got off the continental gouge so I finished the whole bottom of the bowl. Here are the resulting lines all over the place. According the Ken these sand out really easily. :C
129254129255

:2tsup::cool: Whadaya know! Ken is right. After a few licks of 120# paper it looked pretty b*^$% good. :cool:
129256

Here is some tear out left just for research purposes. :C Not so easy to eradicate. :doh: Even on this soft cedar.:rolleyes:
129257

So there ya go. Everyone now has to race out and get continental or traditional gouges.:cool: And don't scrape. Cedar anyway. Next I should try a bit of burl. Just for research.:D Anyone got any? :whistling: (Its OK! I've got some lurking there somewhere.:D )
Tea lady, sorry I was a bit slow responding.
None of the cuts that you have shown pictures of are shear scraping.
The closest that you got to shear scraping was with your continental gouge, thats why you got the best results.
A bowl gouge used as a shear scraper CORRECTLY is the safest way to get a good finish on a bowl. It is impossible to get a catch with a bowl gouge shear scraping, the same can't be said for a scraper or skew.
Some of the people here, that are giving you advice on how to shear scrape, can't do it, I've watched them try.

tea lady
10th Feb 2010, 04:30 PM
Well I think it is quite a useful exercise to try and articulate what you are doing in any field. Its all very well to say "just use the tool". How to use the tool is still a puzzle to beginners and even not so beginners sometimes. I know it takes practice to go able to turn. The next step is knowing what you are doing in a conscious way, and be able to tell someone else what you are doing. "Giving them names" means we can talk about them.

"But giving them names tends to suggest a way the tool must be used and while this keeps the traditionalists happy it tends to confuse the issue."

P.S. I'm not only talking about them. I am using them too.:cool:

tea lady
10th Feb 2010, 04:34 PM
Tea lady, sorry I was a bit slow responding.
None of the cuts that you have shown pictures of are shear scraping.
The closest that you got to shear scraping was with your continental gouge, thats why you got the best results.
A bowl gouge used as a shear scraper CORRECTLY is the safest way to get a good finish on a bowl. It is impossible to get a catch with a bowl gouge shear scraping, the same can't be said for a scraper or skew.Thanks for chiming in Ken. I must admit I was little far away at Groggy's to really see what you were doing. Is it a "bit" like pic 4, but with much more angle on the tool so that the cutting edge is much more on an angle? (I haven't got extreme Elsworth wings on my bowl gouge. I think my really big one does. Will have another play tomorrow hopefully.)

KenW
10th Feb 2010, 04:44 PM
Woodturning is one of the oldest wood machining trades on the planet.
The names of tools are put there for identification purposes so that most people know what you are on about otherwise nobody would have the knowledge they have today.

Every trade has names for tools that don't suggest what they are used for but to a person in the know it identifies which tool to use.
, I think your lecture covered most points.
A couple more, a skew can be made from round bar as well.
Cindy Drozda calls a skew chisel sharpened square across, a negative raked scraper, thats it's correct name.

KenW
10th Feb 2010, 04:51 PM
Thanks for chiming in Ken. I must admit I was little far away at Groggy's to really see what you were doing. Is it a "bit" like pic 4, but with much more angle on the tool so that the cutting edge is much more on an angle? (I haven't got extreme Elsworth wings on my bowl gouge. I think my really big one does. Will have another play tomorrow hopefully.)
Picture 4 is the correct presentation angle, however the gouge needs to be rolled right over until the top cutting edge is almost touching ( as Jeff explained).
I don't use an Ellsworth grind for this cut, a normal bowl gouge with medium wings works fine and saves changing gouges.

tea lady
10th Feb 2010, 05:04 PM
Picture 4 is the correct presentation angle, however the gouge needs to be rolled right over until the top cutting edge is almost touching ( as Jeff explained).
I don't use an Ellsworth grind for this cut, a normal bowl gouge with medium wings works fine and saves changing gouges.:2tsup: OK! I do that. Will take another pic tomorrow to go with the rest.:cool:

But I did like using the continental gouge.:cool:

rsser
10th Feb 2010, 05:06 PM
Ken wrote: Some of the people here, that are giving you advice on how to shear scrape, can't do it, I've watched them try.

K, post some pics eh Ken?

round Skews, from Sorby not that it matters; easy to make yr own from some HSS rod

brendan stemp
10th Feb 2010, 07:08 PM
Woodturning is one of the oldest wood machining trades on the planet.
The names of tools are put there for identification purposes so that most people know what you are on about otherwise nobody would have the knowledge they have today.

Every trade has names for tools that don't suggest what they are used for but to a person in the know it identifies which tool to use.

Yes I know that (I'm not that thick) So I can only assume you missed my point.

The point I was making is that too many times I have seen woodturners misled by the name of a tool. ie spindle gouge is only for spindle turning. And the skew chisel seems to put a chill down a lot of turners spines and they don't use it because of the catch they had. But it can be used in so many other ways. So, its just a name not a description of how it needs to be used.

Second point I was making is to do with the cutting edge of the tool. I'm sorry but every tool that has a cutting edge will cut, scrape or shear scrape or peel or whatever in the same way. Yes, I agree the tool has to be presented to the wood in different ways but that ain't what I was saying. The actual cutting action on all tools that cut (or peel or slice) is exactly the same. And if a tool is scraping it don't matter whether it is a skew chisel or a bowl gouge or a dedicated scraper, they are all taking wood off in the same scraping way. And the same with shear scraping, which is how all this got started.
The reason we have different tools is simply to make these cutting,scraping or shear scraping actions easier and less dangerous.

So, if you still disagree then I'd be interested in your response.

dai sensei
10th Feb 2010, 07:24 PM
Interesting discussion


...Cindy Drozda calls a skew chisel sharpened square across, a negative raked scraper, thats it's correct name.

I thought she was talking more about the skew chisel presented (ie to the wood) square across, a negative raked scraper.

RETIRED
10th Feb 2010, 08:43 PM
Yes I know that (I'm not that thick) So I can only assume you missed my point.

The point I was making is that too many times I have seen woodturners misled by the name of a tool. ie spindle gouge is only for spindle turning. And the skew chisel seems to put a chill down a lot of turners spines and they don't use it because of the catch they had. But it can be used in so many other ways. So, its just a name not a description of how it needs to be used.

Second point I was making is to do with the cutting edge of the tool. I'm sorry but every tool that has a cutting edge will cut, see below. scrape or shear scrape or peel or whatever in the same way. Yes, I agree the tool has to be presented to the wood in different ways but that ain't what I was saying. The actual cutting action on all tools that cut (or peel or slice) is exactly the same. And if a tool is scraping it don't matter whether it is a skew chisel or a bowl gouge or a dedicated scraper, they are all taking wood off in the same scraping way. And the same with shear scraping, which is how all this got started.
The reason we have different tools is simply to make these cutting,scraping or shear scraping actions easier and less dangerous.

So, if you still disagree then I'd be interested in your response.A scraper used like a gouge is courting disaster in the wrong hands and in my opinion is aptly named.

I agree with the rest.:D

Calm
10th Feb 2010, 09:22 PM
Ken please include the angles that the gouge meets the wood Red line (Horisontal angle) & blue line (vertical angel)

Am i right in saying the red line is 45% and the blue line is so the gouge touches midway along the "long" side of the cutting edge with the "top" cutting edge almost on the wood.

The green bit is the top cutting edge and should be rolled "anticlockwise" TO ALMOST TOUCH THE WOOD.

Cheers

NeilS
11th Feb 2010, 12:17 AM
This is becoming a real ripper (not a technical term) of a thread. On'ya for kicking it off TL.

Have noted from this and many other threads on bevel cutting/slicing/scraping/shear scraping that the more experienced turners find it difficult to see why anyone could be confused by any of this, it all being second nature to them. However, developing turners struggle to understand what the terminology means and to know if what they are doing is this or that, or something else altogether.

Carefully chosen words by experts can be helpful in bridging the gap. Photos are a real help. Videos are better again. And, interactive demos by experts and hands-on tutorials are the ultimate, but not possible here, now. However, it would be helpful if we could have more photo and video input from the pantheon of experts that have gathered together around this thread.

PS - The visual input from TL and Calm has been a great start.


.....

tea lady
11th Feb 2010, 07:45 AM
Have noted from this and many other threads on bevel cutting/slicing/scraping/shear scraping that the more experienced turners find it difficult to see why anyone could be confused by any of this, it all being second nature to them.


.....Sheer scraping is the one I'm not quite understanding. And how exactly it differs from scraping. :shrug:

Also I don't think terminology is bad Brendon. If we all can understand the terms it means we can talk about it. Kinda important when all we have to talk to each other are keyboards and 'puter monitors. We are allowed to have jargon. :cool:

brendan stemp
11th Feb 2010, 08:23 AM
Sheer scraping is the one I'm not quite understanding. And how exactly it differs from scraping. :shrug:

Also I don't think terminology is bad Brendon. If we all can understand the terms it means we can talk about it. Kinda important when all we have to talk to each other are keyboards and 'puter monitors. We are allowed to have jargon. :cool:

I have not said or suggested anywhere that the terminology is a BAD thing. What I have said that it can be misleading and can confuse the the issue of what a tool might be used for. See my response to .

I agree about the scraper courting disaster. I heard that Terry Scott turned the outside of a bowl with a skew chisel (used in cutting/peeling mode). Now this too is courting disaster but he did it. But what was the point when there are other tools that make it safer and easier.

KenW
11th Feb 2010, 09:55 AM
Ken please include the angles that the gouge meets the wood Red line (Horisontal angle) & blue line (vertical angel)

Am i right in saying the red line is 45% and the blue line is so the gouge touches midway along the "long" side of the cutting edge with the "top" cutting edge almost on the wood.

The green bit is the top cutting edge and should be rolled "anticlockwise" TO ALMOST TOUCH THE WOOD.

Cheers
David, you are spot on with your angles.
No matter what tool you use, to shear scrape with it, the cutting edge is presented at 45 degrees to the surface being cut (no bevel rub). When you are doing the cut correctly you will produce fine hair like shavings.
The advantage of using a bowl gouge is, it can't catch, thats why I always teach beginners this method.
This cut also removes wood very slowly, making it easy to creep up on a shape .

KenW
11th Feb 2010, 10:00 AM
K, post some pics eh Ken?

round Skews, from Sorby not that it matters; easy to make yr own from some HSS rod
Ern, I have just spoken to , we will organize pictures.

KenW
11th Feb 2010, 10:03 AM
I have not said or suggested anywhere that the terminology is a BAD thing. What I have said that it can be misleading and can confuse the the issue of what a tool might be used for. See my response to .

I agree about the scraper courting disaster. I heard that Terry Scott turned the outside of a bowl with a skew chisel (used in cutting/peeling mode). Now this too is courting disaster but he did it. But what was the point when there are other tools that make it safer and easier.
Life was much easier when we bought round and half round bar gouges.
Tool manufacturers have made things way to complicated with all the fancy names they give tools.

RETIRED
11th Feb 2010, 10:06 AM
I have not said or suggested anywhere that the terminology is a BAD thing. What I have said that it can be misleading and can confuse the the issue of what a tool might be used for. See my response to .

I agree about the scraper courting disaster. I heard that Terry Scott turned the outside of a bowl with a skew chisel (used in cutting/peeling mode). Now this too is courting disaster but he did it. But what was the point when there are other tools that make it safer and easier.I have too but the Valium copped a hiding that day.:D
I agree entirely with the 3rd paragraph.

RETIRED
11th Feb 2010, 10:07 AM
Ern, I have just spoken to , we will organize pictures.They will not be up until about the 22nd.

Ozkaban
11th Feb 2010, 10:21 AM
Thanks for a very informative thread, TL and others. I've been confused by some terminology and have never really understood what shear scraping meant. Pics so far have been very informative and look forward to the new ones.

Thanks again.
Dave

KenW
11th Feb 2010, 10:27 AM
Interesting discussion



I thought she was talking more about the skew chisel presented (ie to the wood) square across, a negative raked scraper.
Neil, a scraper with a second relief angle on the top is called a negative raked scraper.
Usualy the angles are different to the ones on a skew.

rsser
11th Feb 2010, 11:16 AM
They will not be up until about the 22nd.

No rush.

Thanks all.

rsser
11th Feb 2010, 12:44 PM
Just to add, in terms of scraper use, I've learned that while a shear angle (ie as Ken mentioned, 45*) is a good starting point, sometimes it should be varied.

With an interlocked grain platter in Blackwood, it did no good at all and 's advice was to have the scraper (with a burr) flat on the tool rest. Worked a treat.

Alternatively, in coming up the walls to the rim of a bowl, the issue is bowl flex and a 'catch' can shatter the wall. One bit of advice is not to go up that far at all, but I've found that using a Munro scraper head (a tear drop shape) near to vertical still safely takes off some wood and reduces the need for sanding.

Now that's a salvage operation. Good technique should avoid the need for it, but sometimes needs must.

NeilS
11th Feb 2010, 01:55 PM
Am i right in saying the red line is 45% and the blue line is so the gouge touches midway along the "long" side of the cutting edge with the "top" cutting edge almost on the wood.



Perhaps some reference to the cutting edge angle of presentation in relation to the travel of the wood would be helpful to the understanding of developing turners on the forum. ie the angle of the cutting edge in relation to the black arrow in the attached pic.

<link rel="File-List" href="file:///C:/DOCUME%7E1/BRON%26N%7E1/LOCALS%7E1/Temp/msoclip1/01/clip_filelist.xml"><!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:DoNotOptimizeForBrowser/> </w:WordDocument> </xml><![endif]--><style> <!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --></style> The sleeper here being that the cutting edge presentation is also at 45<link rel="File-List" href="file:///C:/DOCUME%7E1/BRON%26N%7E1/LOCALS%7E1/Temp/msoclip1/01/clip_filelist.xml"><!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:DoNotOptimizeForBrowser/> </w:WordDocument> </xml><![endif]--><style> <!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> </style> to the direction of tool travel. No probs if 45<link rel="File-List" href="file:///C:/DOCUME%7E1/BRON%26N%7E1/LOCALS%7E1/Temp/msoclip1/01/clip_filelist.xml"><!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:DoNotOptimizeForBrowser/> </w:WordDocument> </xml><![endif]--><style> <!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> </style> is always used, but if an expert suggests, say 30<link rel="File-List" href="file:///C:/DOCUME%7E1/BRON%26N%7E1/LOCALS%7E1/Temp/msoclip1/01/clip_filelist.xml"><!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:DoNotOptimizeForBrowser/> </w:WordDocument> </xml><![endif]--><style> <!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> </style>, then is that angle in relation to the wood or tool travel?

My meagre understanding is that we are talking about the angle in relation to the travel of the wood past the cutting edge.

.....

brendan stemp
11th Feb 2010, 02:42 PM
Very good point Neil. All talk of what angle you should hold the cutting edge at should be in relation to the rotation of the wood as you have suggested with the black arrow.

tea lady
11th Feb 2010, 08:08 PM
but I've found that using a Munro scraper head (a tear drop shape) near to vertical still safely takes off some wood and reduces the need for sanding.
:think:I think what you are discribing is "sheer scraping" with a scraper. :cool:




My meagre understanding is that we are talking about the angle in relation to the travel of the wood past the cutting edge.

.....:hmm: I guess I think of it as angle to the tool rest- cos that is stationary. :shrug: But its tricky to describe cos it is three dimensional. We need someone with CAD skills.:cool:

rodent
14th Feb 2010, 11:08 PM
Im getting a headache no i've got one its getting worse . As with any trade , hobby , sport or any thing new there is always a new vocabulary . Its just when the yuppie sales department gets hold of it , they have to change the name to make it trendy . $%*& hole& don't get me wrong new tool designs are great , but re vampt old designs with new names ( because they can ) is just bad taste . PS I made a round skew out of 1/4 round ages ago great for them finial thinges anne maria was playing with a while ago .

rsser
20th Feb 2010, 09:05 AM
Lacer and Wright published a comparo that I'd forgotten about of scraper edge treatments in American Woodturner, Winter 2008.

For data it uses microscopic images of both the tool edge and the finish it left after hollowing end-grain kiln-dried poplar* (a timber they regard as hard to cut).

They concluded that while a shear angle improves the finish a far greater improvement is achieved when the top of the tool is flattened and polished and then a burr raised either with a diamond hone or a burnisher.

Even just doing this before producing a burr on a dry grinder leads to a dramatic improvement in the finish.

They make the point that many scrapers come from the factory with poor quality top surfaces and the 1st thing a turner shld do is improve it by lapping (flattening, then honing/polishing it) on a flat stone.

* PS, the section chosen for mag'n in each case was what they called the cross grain section because of its higher prob'y of tearing. See the pics of tool position in shear mode and lo and hi mag cross grain

NeilS
20th Feb 2010, 10:14 AM
They concluded that while a shear angle improves the finish a far greater improvement is achieved when the top of the tool is flattened and polished and then a burr raised either with a diamond hone or a burnisher.



..................:2tsup:

.....

RETIRED
20th Feb 2010, 10:25 PM
Photos taken today.

Will edit and put up when ready.:wink::D

RETIRED
27th Feb 2010, 06:48 PM
Pics and Tutorial here.


http://www.woodworkforums.com/f8/tutorial-shear-scraping-113991/