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Waldo
14th April 2006, 09:21 PM
G'day,

I spent a bit of today lapping and sharpening what was my Grandad's LH skewed end scraper. My question is, it has a blade on both faces, should it not just have a blade on one face, ala a normal chisel? If so should I regrind it?

What do you reackon?

Skew ChiDAMN!!
14th April 2006, 09:37 PM
If 'tis bevelled on both faces, he was probably using it as a skew or a beading tool. But that's no reason to leave it that way; if you want to use it as a scraper go ahead and reshape it. :)

You don't really have to remove the top bevel anyway... just consistently sharpen only the one side when you use it and it won't be long before there's just the one bevel left. Until it's gone you'll need to hold the tool at a slightly different angle to get the burr to cut properly, but I'd rather put up with that for a while and get some use out of the steel instead of simply turning it into filings. :rolleyes:

Waldo
14th April 2006, 09:50 PM
G'day Skew,

Thanks for that, was hoping you'd come in with some advice. My thoughts were along the same lines, so I'll do just that.

ubeaut
15th April 2006, 09:52 AM
Possible it is (or was) a shear (sheer) scraper, they are often bevelled on both faces. Different kettle of fish to a regular scraper, also used in a different way.

cheers - Neil :)

Waldo
15th April 2006, 11:51 AM
G'day Neil,

In what way is a shear scraper used?

Gil Jones
15th April 2006, 01:10 PM
Waldo, have you ever considered changing the shape into a negative rake scraper? http://www.woodturnersofswmo.org/Newsletters/WSWMO%20Newsletter%20October%202004%20Page3.pdf (http://www.woodturnersofswmo.org/)

ubeaut
15th April 2006, 11:36 PM
Waldo - Rather than sitting flat on the tool rest a shear scraper is tilted on an angle of around 45-60 deg. and can also be used (in the right hands) without the aid of a toolrest. Basically you are presenting the tool at a sheer cutting angle rather than a straight on scrape. I'm not a user of scrapers and never have been but have seen the the shear scraper used by Vic Wood and other top flight turners with excellent results.

Cheers - Neil :)

Skew ChiDAMN!!
15th April 2006, 11:45 PM
They're still presented with the tip lower than the handle, BTW.

Just a safety pointer. ;)

BTW, all my scraping is done skewed. I still leave the tool sitting flat on the rest, but adjust the angle so it's presented appropriately across a section of grain. It makes for a far better finish, all that's missing is the bevel rub. The only time this can't be done is when scraping square on to the item while spindle turning... and 'tis easy enough to avoid this. That's the mistake most novices make and don't progress beyond, being told "real turners don't scrape." :rolleyes:

ubeaut
16th April 2006, 10:06 AM
Think you'll find a shear scraper is usually presented to the timber with the tip of the tool horizontal or at an angle higher than the handle. Rather than in a conventional scraping action.

You can get a much cleaner cut and finish by sheer scraping than you can with a conventional scraper and with less likelihood of a dig-in or chatter (when used correctly).

Most edged tools can be used as sheer scrapers especially gouges and this is why I'm not really a user of scrapers. There are the odd times when nothing but a conventional scraper will do for a particular job and for this reason and this one alone I have a couple of scrapers in my kit.

30 years and thousands of hours of turning later my scrapers all are sharp but none have lost more than a couple of mm from sharpening during that time, matter of fact they all look like new tools. This is how often I have had to use them. Matter of fact most of their use was at the hands of my students rather than me.

Cheers - Neil :)

PS I haven't picked up a turning tool for about 3 years now. Was going through all the stuff we moved from the old factory to new one the other day and found my turning tools which had been put away with due reverence (chucked into 4 x 20 litre buckets) All were rusty and begging for a good clean up. Did I weaken and clean them up. Nah!!! Another day.

Skew ChiDAMN!!
16th April 2006, 07:59 PM
??? :confused: You've lost me here, Neil.

Correct me if I'm wrong, but AFAIK as soon as you move the tip above the handle the cutting action changes from a scraping cut to a planing cut? Sure, people say you're scraping as soon as you stop bevel rubbing, but it's not scraping per se... it's just a bad (in general) planing technique.

I was taught a sheer scraper was presented to the grain in basically the same way as a skew chisel, but tip down in scraping mode (cutting with a burr) rather than tip up in planing mode.

Or are you talking about something different? Not trying to be contentious here, I'm just confused...

Skew ChiDAMN!!
17th April 2006, 07:27 AM
Lying in bed, I think I've had a Eureka! moment! :D

OK, the wife thinks I'm lost it, jumping out of bed in the wee hours, muttering "I got it!" and rushing to the 'puta... but I couldn't sleep and methinks my subconscious has been working overtime. For some reason the ol' grey matter has been looping over playing with pole lathes and traditional hook tools, enough to keep me awake. :rolleyes: Then I realised that the hook tools are scrapers used before toolrests became common and were used point up!

The difference being that they were used on the bottom of the wood, where the timber is receding from the tooltip. Since toolrest have become so common we use them as the reference point, hence the "point up" & "point down" differentiation between planing and scraping... but in ages past without that point of reference it'd have to be defined as "grain advancing" & "grain receding." When working freehand, without a toolrest, I always work point up as you can hold the tool with better support, but if you insert an imaginary toolrest in at the appropriate spot (which is near the bottom of the piece) and imagine it all rotated around so the rest is near the usual "half-way up" position, the point would be down.

Is this what you were referring to??

I certainly hope so, otherwise I'm even more confused. The only other way I can see a "sheer scraper" being used in a planing motion is if you're misnaming a skew chisel! ;)

ubeaut
17th April 2006, 10:47 AM
Geez Skew - Definitely not worth loosing sleep over. It isn't an old method quite the contrary it is a relatively new process probably only a few years old.

Often the tool is taken from the horizontal to the top of the work on the inside of a bowl the tool is usually presented at an angle of 45-60 degrees to the tool rest (never laying flat on the tool rest). On outside work the tool is held at the same angle to the tool rest and usually horizontal to to the work.

If you really wish to learn more pay a visit to Vic Wood or come to Downunder Turnaround in Sept, I'm sure there will be a few people who will be glad to demonstrate sheer scraping.

Here is a link to some sheer scrapers just to give you an idea as to how they look. http://www.turningtools.co.uk/ashleyiles/turntols/turntols1/turntols-pages/sheerscrapers.html I think you might find a small video clip on the Sorby's site for their sheer scrapers (wouldn't buy one but the vid shows the angle the tool works at)

Skew ChiDAMN!!
17th April 2006, 01:56 PM
Geez Skew - Definitely not worth loosing sleep over. It isn't an old method quite the contrary it is a relatively new process probably only a few years old.

It's not like I had any say in the matter. Believe me, if I had an off switch I woulda used it. :D

I hit the Sorby site and looked at their' "micro shear scraper" video but it's just an ordinary scraper with a changeable head. :rolleyes: I assume they've just called it that 'cos it scrapes diagonally to the grain and not straight across it, but every scraper should be used that way.

Ah well, I'll keep looking into it. Thanks!

Gil Jones
17th April 2006, 03:03 PM
Check out this site for a rather different shear scraper.
http://www.maine-web.com/woodturning/shapeshifter/scaper.html
I tried his idea on an old bench gouge (see pic) and it works great, inside or outside of a bowl.

Skew ChiDAMN!!
17th April 2006, 03:18 PM
Now that's a damned good idea, Gil! With the curved back you don't need quite as acute an angle to get the shearing action, so can hold the tool at a flatter angle and, hopefully, get further reach. Good stuff, I'll try it!

Greeny sent. ;)