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I have one and love it. Much easier to use than a card scraper. Easier on the hands - less tension - no bending or thumb pressure required. Also no corners to dig into your Spruce or WRC top. Great for taking down purflings and bindings, scraping sides, even shaping necks, etc. Sharpening is a bit different, as you need a fine wheel to do the hollow grind, and the angle has to be right, but there is no turning a burr involved. Just sharpen and use. Watch the video.

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Waddy

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Sound Clips of most of my guitars

Waddy, have you needed to sharpen yours yet?? (...& if so, how'd it go?)

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Dave
Milton, ON

What Waddy said!!!!! Haven't had to sharpen mine yet, and I need to buy a fine grade wheel anyway for my bench grinder.

Mike

I did run mine against a fine 6"wheel on the high speed grinder, but I used a very light touch and ground it just short of perfectly tangential to the wheels edge, to force only one edge contact at a time, then flipped it over and did a quick pass on the other side. Seems to have worked fine. A smaller, fine 4" wheel on the slow speed grinder would have been better, but it was covered up!

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

The key to sharpening is the "hollow ground" edge, according to what I have read. That's why I think a smaller wheel would be better than the 6" one I used.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

I have a pair. Love them. Only used them for binding so far though.

Cheers,
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"

Why do you need a scraper?

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

to be admitted in the scraper brotherhood, for instance.

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member of the guild of professional dilettantes

Waddy,

What I do not understand is - how is running this along a grinder creating the hollow ground blade ?

*I think Peter M forgot to add the smiley face to his post...

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It's this new idea from recent decades that everyone gets a participation award. - MUX

If I can answer John, I think the idea is the scraper is so thick, by grinding exactly on its centerline, you create a hollowground the same radius as your wheel.

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Dave
Milton, ON

I learned about that style of scraper from Carleen Hutchins, and she from Sacconni, who said it was the kind that Strad used. At any rate, it took me a while to get around to trying it, and then I wondered why I'd put it off for so long. My students all felt the same way about it, and we spent too many class sessions pulling red-hot steel out of a dental investment furnace and dunking them in cans of oil. Then I got a student who's brother-in-law runs a machine shop, and we fobbed the whole thing off on him. To help make it worth his while, I talked the idea up to Stew-Mac, and now I'm off the hook for making them. Woo-hoo! I'll note for the record that I don't get any commission from this.

I do find these much easier on the hands. For one thing, you don't have to spring them (just try!), so you can use it one-handed on either push or pull strokes. Since it's thick it doesn't heat up as much. The added mass also helps keep them from chattering so much. The hard steel tends to hold an edge better than spring steel, and will even work for a while on shell and recon stone. This might not mean you sharpen less, though: I find I've gotten spoiled and tend to touch it up as soon as it starts to seem a little dull. It's easier to sharpen, particularly for beginners. I used to tell my students that it would take them a year to get the hang of sharpening a card scraper, and they's sort of roll their eyes. A year or so later they'd remark that they were finally starting to get the hang of it...

The main down side is that you can't just sharpen these with a file: the steel's too hard. I've always used a bench grinder, and leave the 'fine' wheel tool rest set up for that. Several people here and elsewhere have mentioned skate sharpeners, which look as though they'd work well, although I've never tried one. The hollow grind is mostly a convenience, you know you've got the same sort of edge on both sides. You could lap the surfaces and then use a guide block on a stone (I'd use a diamond stone, to keep things flat and straight) to get the edge. In fact, when I want a fine edge for scraping soft woods I usually lap the faces and run the edge around the diamond stone to get a light, smooth burr (I'm pretty sure that's on the video...). Some folks use a belt sander...

The little scraper is the 'violin' size, although I tend to use that one a lot for scraping bindings and other small jobs on gutiars. I would not want to make a fiddle or archtop guitar without one of these: it's so much better that the thin scrapers for these jobs that its just in a different class. I do a lot of the shaping of arched plates, both coarse and fine, with the scrapers now that I have them. On fiddles I usually finish with the scraper, not touching the wood with sandpaper at all. It gives the look that the violin people like (and guitar people hate...).

A final note: not everybody likes these as much as I do. Different people have different ways of doing things, and this might not fit with their process, shop setup, or skill set. There are things that are easier or better done with a card scraper, too: I still have those, and use them, although not every day the way I do the heavy one.

So you would hold the scraper basically vertically on the tool mount against the wheel ? You are removing material between the two thick cutting edges, to make it dipped in the middle of the knife edge ? If this is so - then how do you know you are removing material evenly ? I guess it might be obvious if I owned the scraper or a bench grinder... anybody have a sharpening picture to show ?

*** OK watching the video now - it would not load up for me last night -

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It's this new idea from recent decades that everyone gets a participation award. - MUX

I've had one for a few months, now. I love it. I use it for scraping bindings flush, scraping rosettes, and smoothing surfaces. I've only gotten my card scraper out once since I got the Carruth scraper and I put the card back in the drawer almost immediately. I have sharpened it once on a fine wheel as directed. It took me a couple of passes to get the guide right, but after that, sharpening was a breeze. As stated above, it's much easier on the hands, doesn't chatter, and cuts better than a card scraper. It looked expensive until I used it. I've since bought another to give to a friend.

I have an order for one sitting in my StewMac cart right now, but since I know Bob's buying them...... . I'm excited to try it!

I purchased one of the Carruth scrapers from Stewmac a while back and absolutely love it. I had made one out of O1 (oil hardening) tool steel several years ago after reading Al's article on the thick scraper. The ones from Stewmac are made from D2 tool steel (if I understand correctly) which is probably the ultimate tool steel from the standpoint of edge strength and wear resistance. The ability to scrape spruce without tearout is a given with the Carruth scraper. I did resharpen it on the Tormek after using for quite a few different scraper applications even though it still seemed very sharp.
My only suggestion might be to relieve both sides in the center area leaving only about 1/4" of flat surface around the outside to facilitate lapping.

I still have (and use) the one I made with Al seven years ago, it's a great tool. Glad to see you finally convinced StewMac to carry them, Al - you were talking about it back then!

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

The first heavy scrapers I made were ground out of an old power hacksaw blade. It took a while... They hold an edge much better then the ones we've been making of D2. One of my other students works for a company that uses a lot of stainless steel, and they have an x-ray gun gizmo that can be used to check an alloy on the loading dock. Some types of stainless are hard to distinguish from others, but won't work for their application, so they need to know they've got the right stuff. Anyway, he brought the gun in one day and checked out my old scraper: it's M2 steel.

My former student and I have talked about their bringing out scrapers in the better steel. There are several issues, mostly revolving around price. As bobgramann said, these things can look expensive until you've tried them, and we figured that we had to keep the catalog price below $30 to get enough out to make it worth everybody's while. We also hoped that once folks had tried them they might be willing to spring for a bit more to get an 'improved' version. M2 is a little more expensive as a material than D2, but, more to the point, the shop has not got the heat treatment facilities to properly harden them once they're cut out. If sales of these things keep up at a good pace maybe the improved version won't be delayed too long. Not that the ones they're making now are 'bad': I use them all the time, but the harder alloy does make a difference in how often you have to sharpen.

I have to say I'm heartened, but not surprised, by the reception these tools have gotten. It took a while to get all the ducks lined up on this, with all sorts of issues getting in the way. Now that it's working, my formerly-unemployed former student at least has something to do, Stew-Mac makes a little money, people have a tool they like, and I'm off the hook. Talk about win-win-win...

I don't use a scraper for anything.
Seems like a slow mover to me.... just wondering what you guys use it for in guitar building...

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

Really? It's one of my most used tools. Smoothing out plane marks after using that to thin things, leveling inlays (works on shell, and doesn't fluff up dust like sandpaper), fine tuning surfaces that are just a hair out of flat, freshening up surfaces for gluing if it's been a while since they were initially surfaced, scraping out any scorch marks on sides/bindings after bending, various shaping tasks like arching the underside of the bridge to match the soundboard radius (although I follow up with fine sandpaper on the guitar to precision fit it). I like the surface texture it leaves, so pretty much all my finished surfaces are scraped instead of sanded.

Basically, does most things sandpaper does, but much faster and with more control, and doesn't go in the trash as soon as it's worn out

Chisels make nice detail scrapers too. With the beveled blade instead of a rectangular edge, you can get into really tight spaces. Great for doing relief carvings, where it's difficult/impossible to get sandpaper down into the nooks and crannies.

A well sharpened scraper is about as slow as a finely to medium set block plane. As Dennis said: much faster than any sanding operation.

I once took a guitar neck blank on a family vacation. I was going to carve it with my brother there since it was for him. I forgot to pack my rasp. The only tools I had were a flat scraper and a French curve scraper. I did the whole thing from square blank to finished neck with those two scrapers in two short evening sessions sitting by the pool. They are plenty fast, accurate and versatile.

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Bryan Bear PMoMC

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

Mine is on it's way from StewMac! I'm in the end stages of carving a neck, and want to finish it off with the Carruth.
I also use a scraper to flush all my bindings, and I think this one will really reduce my hand fatigue.

Scraper, most used tool in my shop next to clamps, indispensable. I think I will get me a Carruth scraper and try it out.

Joe H.

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Joe

My wife asks me "How many Guitars do you need?"
I reply "When I die count them; thats how many I needed".

Although I don't have the Carruth scraper I did make something similar from a HSS plane blade. That and numerous card scrapers. I find it hard to believe that someone can make a Guitar without using a scraper. I'm sure it's possible though.
Certainly faster than sandpaper, cheaper (in the long run) and doesn't produce dust - or at least it shouldn't.

Al had mentioned that you could use a belt sander for the sharpening - has anyone tried that yet ? Wouldn't you be missing the hollow ground since the belt sander does not have a radius like a wheel does ?

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It's this new idea from recent decades that everyone gets a participation award. - MUX