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I'm sorry if I just rediscovered the wheel, but here it goes anyway.

Normally, one prepares and sharpens the scraper on stones then turns a hook with a burnisher. When it gets dull, the hook can be resurrected by burnishing one more time. IME trying this a second time (a total of 3) doesn't give any usable result. It's time to bring it to the stones again.

Well, the trick is to "burnish" the third time using a fine cut file the same way as using the burnisher, at a small angle (say 80 between scraper and file). This seems to sharpen the hook a fair deal giving a few more good minutes of work. Of course it is not the smoothest shaving as given by a fresh hook but it does cut a solid shaving instead of dust.

Hope this might be useful to some of you. At least for me, truing a scraper is such a drag, unlike the poetry of doing a Japanese plane iron and stuff like that

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Build log

If you are trying to raise the hook for the second or third time, you need first of all to to lay the scraper flat on the bench, and run the burnisher along the edge, prior to raising the hook.

You won't get a satisfactory hook second or third time round just by burnishing in the same way as you would do with a freshly stoned edge.

Thanks, I'll try that!

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Build log

I never have gotten good at turning a hook on a scraper. Gotten it great a few times, but now I just use the method from Ervin Somogyi's book, where you polish up the faces near the edge, and then clamp it in a vise and run a file along the edge a few times to make a sharp 90 degree edge on each side. No hook, just use the 90 degree edge directly. Way easier, shaves plenty fast, and only takes a few seconds to resharpen so you can do it every couple minutes for an always-fresh edge

Yup

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Dennis, from what I saw so far, getting a great hook depends heavily on having a very well stoned edge, very sharp and nicely polished. If you run your finger on it and doesn't feel like it is able to cut you off, it won't take a nice hook. When it is perfect, the hook is small but effective, and can be created with little, and light burnishing. At least for me it takes a good deal of elbow grease to reach that state though. Often I stop the stoning somewhere midway then resort to harder and longer burnishing to turn a hook, which of course doesn't work that nice. Anyone knows a good shop that sells patience?

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Build log

All this effort may not be necessary for other than finsih work. Richard Brune once showed me that he lays the scraper down on the support in front of a grinding wheel and runs it back and forth quickly at 90 degrees to the wheel. It is then ready to use with the burr remaining from the grinder. He scraped large amounts of wood immediately.

I generally have a rather large stock of patience but with the last two guitars I've build, my stock is nearly depleted so I can't sell you any. Mind you it's rather costly and the shipping over to you would be rather expensive mind you, I could really use a nice trip to Romania

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

Sure, I'll guide you in the Carpathians and harvest some blood-red spruce from Dracula's castle hill

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Build log

Here's my take. Draw file and forget trying to stone the entire edge. If you want to take out the scratches left by the file it's much quicker to draw file with something finer - silicon carbide glued to a piece of wood. We only tend to use the central part of the scraper anyway. Trying to true the entire length of the scraper seems a waste of time to me. Then it's just a case of removing the burr in the normal manner.

I learned a method from Charles Fox that's similar to what Dennis describes above. Use the file in the same way, but with the scraper still in the vise, use a burnisher (you can actually use a round screwdriver shaft - I use an old knife sharpener like chefs use) to turn a hook by running the burnisher along the edge of the scraper holding the burnisher at a slight angle. Takes 30 seconds and works like a charm.

Chuck

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That's the quick and dirty method, but you get a rough burr that doesn't last long. A well sharpened scraper is a different experience.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I have the impression that the hook lasts longer if you consolidate the edge by passing the burnisher flat along the edge before forming the hook by angling the burnisher.

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"Building guitars looks hard, but it's actually much harder than it looks." Tom Buck

Hey Alexandru, have you seen this scraper jointer thing from LV? I have one and think it's a "cool tool."
http://www.leevalley.com/US/wood/page.a ... 31&p=32631
regards
pvg

Here's a trick I learned online and works quite well, believe it or not. First I true up the faces and edge on a coarse continuous diamond stone, very fast. Then I burnish, first with a few strokes at 90 degrees and then at the angle I want. Then I scrape an MDF board, about a dozen long strokes. Then I burnish on an angle again. With this I get nice shavings, no dust. It appears the MDF polishes the edge. Go figure.

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Randy Muth
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Yes, I do something similar. Run the scraper along an edge sander. Instead of at a 90 degree angle and rolling over two burrs I hole it at a 45 degree angle and roll over one large burr. For scraping rosewood and other rough stuff it works great. If you ever want to do finishing scraping then I use stones to hone it and get a less jagged edge. Seems to me I did a Luthier Tips du Jour video once on this.

MDF is pretty rough on tools, but I think that is the point. It removes the jagged edge. It's still a bit weird, but it works well.

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Randy Muth
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One more thought, I think it just acts like a very fine abrasive, like using a fine stone.

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Randy Muth
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Lots of different ways to do essentially the same thing. Brian Boggs has a nice little video on the Taunton website http://www.finewoodworking.com/PlansAnd ... px?id=5233

Man that MDF method is intriguing, I'll have to try that tomorrow.

Ian, let me know how it works for you.

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Randy Muth
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Certainly will

I did a scraper this morning. Ran it across a file, burnished it up, scraped some MDF, burnished it again. wow. Works crazy well. I got plane shavings from the thing after. I was using my thickest scraper.

Wow, so it even worked when using a file. I use a diamond stone which is about P360. I'm glad it worked for you.

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Randy Muth
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