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I posted this in the electric forum before realizing that acoustic builders might have more knowledge on the matter. I need to buy a sharpening stone for some scrapers I just purchased but I dont know anything about sharpening. What should I get?

I just use a file to prep the edge and sides, and then go right to the burnisher. I suppose it doesn't give me an atom splittingly sharp and consistent burr, but it is certainly up to the task. If I really wanted to get picky I would prep with the same sandpapers I use to sharpen my chisels and irons. . .

I'm probably being pretty lazy here and will follow this thread with interest to see what others say/are doing. In the interest of full disclosure, sometimes (if I am just rough scrapping) I use it straight from the file; there will be a little burr form filing the edge (and not the sides) which will work in a pinch. . . Told ya I was lazy.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

File then burnish. I do use a fine cut file but they seem to work.

I just took a sharpening class and they covered scrapers. Do as the others said. File the edge of the scraper and the remove burr. Then burnish. Not real difficult, but then most things aren't once you know

File, then a fine diamond stone, then a carbide burnisher from lee valley,or their easy to use lee valley graduated in deg style burnisher

I file then use a stone before burnishing.

Great information, Thanks.

I can't say enough good things about this scraper sharpener from Lee Valley:
http://www.leevalley.com/US/wood/page.aspx?p=32631&cat=1,43072,43089
Not only does it work great for cabinet scrapers, it also does a fantastic job on #80 style scrapers that use a 45 degree angle.

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Stay with the happy people.
--Reynolds Large

I've always had great results from prepping the edge with a mill file. Everything else is accomplished with a chisel, although it is absolutely necessary that your chisels are made from the hardest steel possible, I have friends who went cheap for their chisels for whom this method does not work. My set is made by Ashley Isles and I can't recommend them enough, Two Cherries makes an excellent set for the money, and all of the high end makers are fine on this as well. Simply draw out the edge with the face of the chisel and form your burr with one of the sides. This is where I see most people screw up either from applying way too much pressure or holding the chisel at much too shallow of an angle. The burr literally only needs to be a few degrees off from perpendicular to the scraper or it won't work properly. I've tried all kinds of elaborate setups and burnishing tools, but have never been sufficiently convinced to stop using my chisels.

I think any process after the file is just a waste of your time. You don't really sharpen a scrapper like a chisel. You create a flat edge then roll a burr on it....Mike

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Another day, another dollar.

great link to fine woodworking.

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"Preoccupation with an effect gives it power and enhances the error"
from "Your Owner's Manual" by Burt Hotchkiss.

I used Brian Burns technique on one of my scrapers last evening. It really makes a difference in cut and surface finish.

I do the file then burnish routine, mainly because I usually end up rounding the edge a little if I take it to a stone. I've always struggled with sharpening by hand without the crutch of a sharpening jig.

Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

I can't say enough good things about this scraper sharpener from Lee Valley:
http://www.leevalley.com/US/wood/page.a ... 3072,43089

Bingo! That's the tool that made scrapers useful for me. I wear out a file in about a year, so if there's a "trick" I can pass-on here, it's to keep a good, fresh, sharp file in it, and when you buy the file, take a good, known straight edge with you and check the files, and only buy the decently straight ones. If you never have, and start checking your files now, you'll likely be surprised at how bowed most of 'em are...

Then I lightly turn a burr with a screwdriver or something; only tip here is to always have a bit of oil of some type on the scraper's edge; I keep a small bottle(hair color bottles are a staple in me olde shop) with mineral oil for odd stuff like this. Oh, another 'tip' is to not bear-down on the burnisher! It took me a long while to figure out that I was pressing way too hard while turning the burr, and would end up with a burr that was turned too far. Just barely 'kiss' the surface 2-3 times. I've seen videos where the fella makes many passes, but I find that a slow, calculated "pass" from end to end is better than randomly bouncing off the edge...

Yes, we can hone and refine scrapers to a fine edge and revel in the shavings, or we can take 10 seconds to get the edge 98% of the way there and get back to work.

Really interested in trying out StewMac's new Al Carruth scraper, too. Hope to bring one in with my next order, if I can remember(placed an order this week and forgot the scraper...).

Just another option to consider:
http://www.stewmac.com/shop/Tools/Scrap ... raper.html

One more last tip.....

Please, do NOT sharpen both edges. Just because a scraper has two(4, really...) edges doesn't mean you should sharpen all of 'em. A well sharpened scraper is a wickedly sharp tool and will slice your hand(s) in a nano second if you're not careful. Just because it looks like a simple tool doesn't make it any less dangerous.

That sounds like the voice of experience speaking, Mario.

Got the scars to prove it, too.

Another useful tip is those magnetic calendars folks give away. Cut them up into squares and stick em on the scraper. Push your thumbs against that - protects against the heat.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Great tip. I have actually scalded my thumbs from leaning into a scraper whilst leveling bindings. Yeouch!

Ken

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Mountain Song Guitars www.mountainsongguitars.com

I prefer to think of the heat as a warning to slow down or back-off, so I -want- to feel it.

I had to do a lot of the thinning on some Honduran rosewoods sides by scraper, due to some knot shadows causing the grain to tear if I used a plane. I wear gloves for the heat, but still had to stop regularly for fear of creating embers in the pile of fluffy shavings

There's also the Veritas scraper holder, but I haven't had good luck with it. Get much better shavings holding the scraper directly.

As for sharpening, I currently use a file on the edge and then burnish from the faces, then the edge, and then angle the hook back maybe 10-15 degrees. But that does leave the faces to get a little rough after a while, which I hope to solve using the DMT extra-extra-fine diamond stone I bought recently.

Perhaps I can use diamond stones in place of the file for refreshing the edge too. As it is, my hook isn't quite as smooth as I'd like it to be. The scraper that came with the Veritas holder worked better when I first got it, and gradually degraded to the level of my other one with each resharpening.

Also, I always round over the corners, because the two on the cutting edge can scratch the wood, and the other two poke my hands. I've never run into a situation where I wished I had sharp corners on a card scraper. Whenever I need sharp corners, I also need a chisel style beveled blade that can get into tight spaces better than a 90 degree edge.

One of the advantages of the heavy scrapers is that they don't heat up as much. you can still feel them getting warm, but I've never gotten one hot enough to burn, as I have with a thin card scraper.

I'd like to mention that I'm not getting any 'cut' on those scrapers that Stew-Mac is selling. I was lucky enough to have a student who could make them, and I introduced them to Stew-Mac so that I wouldn't end up in the mail order business. I kind of wish they had not put my name on them, although I understand why they did. I'm just happy that I don't have to be pulling red hot steel out of a furnace and dunking it in oil any more during classes: that's not really good practice in a wood shop. Once the students tried my scrapers they had to have one, and that was the only way to get them, up 'til now.

My own view on scrapers is much like others view sandpaper. I have quite a few, and sharpen them differently depending on use. Some are lightly filed and gently burnished and perform like 80 grit. The next set are filed, then stone sharpened and then gently burnished and perform like 120 to 180 sandpaper. My final set is further refined on finer stones (1200 then 4000 waterstones) and not burnished at all, for very fine finishing of the surface prior to sealing and topcoats. No need to 'raise the grain' and remove hairs.

I file and burnish, seems to work well enough..
Also if you wanna save money on scrapers - take an ordinary hardware store saw... rip or crosscut made with good quality steel, and cut a few out of one with an angle grinder with a cutting wheel on it then square them up with files or sander - I did that for all my scrapers and they seem great ... really fine transparent curls ..
Good Luck
Cw