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I can't seem to get a scaper do do much more than sawdust. Occasionally i'll get some fine shavings but it doesn't last too long. Nor is it ever like the real shaving i've seen in some videos. That was fine on the top as i am using punky cedar so a slow cut was ok. Now, I am using it on poplar which i don't see as being particularly hard wood so i am surprised the edge doesn't last. I've watched a few videos and don't understand what i am doing wrong.

Am i rolling the edge too much? To little? Too much pressure or too little when forming the edge?
If i am getting dust, do i need to roll more or less?

When i use the tool. it seems to work best at 45 degrees. Does that indicate anything about my edge?

I am using quality scapers from woodcraft. I have re-sharpend maybe a dozen times so far. Is the learning curve longer than that? Is there an "AH-HA!" moment?

I am not using anything to guarantee a perfect 90-degree when i file the edge. Just doing it by feel (flat file in my hand). Does that need to be perfect?

Going to break down and use the orbital sander soon. *sigh*

Thanx for any comments.

My first set of scrapers were decent, I thought, but I had the same problem you have. Then I got a set of Lie Nielson scrapers and all was good with the world. Maybe I just finally learned to sharpen them correctly but they sure work nice.

I also use a mill file, maybe 3 or 4 strokes to square up the edge. I also lay the file flat on the scraper side and remove anything, very lightly, that is left of the old turned edge. Then I clamp the scraper in my wood vise with about 1 inch exposed and turn the edge with an old, cheap, screwdriver with a square shaft. I hold the screwdriver at about a 20 or 25 degree angle to the top of the edge and use two hands and a fair bit of pressure. I have one of those hand-held burnishers that you use with one hand and I just couldn't get it to work well so I don't use it anymore.

Come to think of it, I think I started using the screwdriver about the same time I got the Lie Nielson scrapers. Hmmmmmmmmmmm

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Steve Smith
"Music is what feelings sound like"

There are many tutorials on the net.
One mistake I was doing was to not flare the top before turning the hook.

Here is a little vid I did just for fun, on how I do a scraper. It seems to work for me. I don't know how to embed a photobucket video, so here is a link.

http://s267.photobucket.com/albums/ii30 ... 5_xvid.flv

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

I am running the sides over 320 grit wet/dry to get rid of anything, and a perfect 90. Watch the vids and make sure your doing it right. A good burnisher would also help.

What you dont see is that your suppose to use a pointed burnisher (they dont make many any more) and hit the inside of the flange with that. But a good burnisher would also help. 3 passes might not be enough.

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Honing stone? Can someone explain to me what this does for the scraper. I just don't seem to get the use of honing stone in reference to the clip Alain posted.

Also, can other sharpening stones take the place of honing stones when it come to that purpose?

Thanks, David

There are various ways to sharpen a scraper without going through the burnisher ritual thing and making everything complicated.
One is a coarse diamond stone (say 320), running the sides and then the edges of the scraper, the goal being to have a perfect sharp angle there, it doesn't have to be 90º as long as it's constant.
The other method (which I use) is a mill file I clamp on the side of the bench. I "file" the edge of the scrapers, maybe 10 times, and periodically swipe the sides to get rid of any burr and debris there.
It works, is sharp and controllable and produces fine shavings.
Maybe the turned burr with the burnisher produces a finer finish, but in guitar building I have yet to not finish sand one surface.
Old saw blades are perfect for scraper material.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

I found this show, originally on the DIY network to be very helpful.

Sorry, had to edit the show out, it wasnt the one I was thinking of. I'm trying to find David Marks' show on sharpening. I'll post when I find it.

http://www.diynetwork.com/diy/ww_materi ... 29,00.html

Ok, that link should work. It's very informative on scraper sharpening.

Darrin

I sharpen scrapers for a fine cut & a heavy cut.
Fine for rosettes and to get a smooth glasslikesurface.
Heavy for removing wood;likesome bindings,fingerboard shaping .

I use old saw blades (.040)also and some thin .020 ones for small spots.
I use a file to clean any burrs on the scraper-then use a super hard burnisher to draw a small curl from the flat body of the scraper then turn that curl to about a 7 to 10 degree angle.
They stay sharp along time (the thick ones) and can remove lots of wood.
I do not use a scraper on Cedar tops to much-just to soft.

Mike

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Mike Collins

Veritas or somebody sells a scraper sharpening jig. Works like it should. I think I got mine at Woodcraft. Comes with everything you need. But it helps to understand the "physics" of the process. With the file and the stone, you are creating a "perfect" square edge. You do not need to do this every time, burnish more often than the rest. But eventually, the edges will need to be repaired. Burnishing squeezes a flange out to either side. Roll that over a few degrees for a perfect scrape. Eventually that "flange" will have too many cracks and missing parts, so you must again file and stone the edge.
BTW, I do not use the stone, but I might after seeing the video.


Mike

I have one of those Veritas gizmos, and I can't get it to work for Jack! I get much better results by hand.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Stop trying to impress Jack, Waddy. Mine works great! Though I can do them without the jig too..

Mike

Me too Waddy! I thought I was doing something wrong. Glad to hear I'm not the only one who can't get it to work....

I use my LapSharp system to clean my scraper edges up, then burnish with a rod and I'm done.
I use the Veritas scraper holder which does seem to work nicely and saves my thumbs from all kinds of pain.

Dave F.

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Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"

I never had good luck burnishing a scraper's edge until I started oiling the edge I was trying to burnish. That was the difference for me.

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Waddy, I think the jig is best for squaring the edge. I still prefer to put the scraper in a vise and hand burnish the edge. I picked up a good tip here, using oil. That makes a lot of sense.

Mike

Work-hardened edge? My impression has been that steel does not work harden; only non-ferrous metals do. The remains of the old burr need to be removed, of course.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I had only modest success setting up a scraper for light cuts. A few swipes and it was dull again (on tropical hardwood, I mean). I needed a more aggressive cut and couldn't make it happen. Then I saw a tutorial for setting up your scraper for just a single sided cut. Rather than getting a perfect 90 degrees, this method has you grind the edge to a 45 deg angle. You then flatten and roll the high edge.

It proved to be very easy, and produced a superb high cut scrapper. I use it to thin stock with a Wagner and then smooth out all the tool cuts (of which Wagner leaves a lot). Produces shavings on even the most difficult wood.

That's what I do too and it works well for my needs. In fact it works so well that for the most part I don't even sand the back and sides much anymore. I never hit top wood with a scraper though, too soft.