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Hmmmm.....
Seems to be a run on these scrapers at Stew-Mac, as they are back-ordered.....
I wonder if this thread had anything to do with it....

This may be a dumb question, but the grinder threat borne out of the desire to use these scrappers makes me wonder. How did Stradivari sharpen his?

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Bryan Bear PMoMC

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

Steel was so much harder than wood back then, it never needed to be sharpened.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

Strad probably got one of the apprentices to do it on a hand stone, although, of course, they did use hand-cranked grindstones back then.

I got my first Carruth scraper about eight years ago. I was helping a friend make a mandolin and didn't want to carve the top and back with just a finger plane and gouge. I asked Al about it and he traced the outline of one of his smaller scrapers on a piece of paper. My friend's dad worked in a machine shop and cut out three blanks from some A2 tool steel. We went up to Al's place and he pulled out his dental oven and we hardened them and then tempered them.
Then the work began. The scrapers came out of the oven a smokey black color. We then had to flatten them on a stone. This took a long time and I ended up grinding an area out of the middle of the scraper to cut down on the work of flattening.
Once flattened, I sharpened just as Al describes in his video.

Since then, Al has brought me prototypes of his scrapers as he and his student have been working on them. I now have six or seven and they are the only scrapers that I use. I have a card scraper but I haven't used it in years.

My scrapers need to be sharpened more often than Al's original ones. This is probably because of the steel used as he describes above. Sharpening is so easy, though, that I don't worry about.

John A.: Sure it does..............!! It's even better than a grinder.
Tom

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A person who has never made a mistake has never made anything!!!

Question: On average how many types of scrapers does one have? Does one need?
Would this scraper replace the need for more than one scraper? Is this a good tool for a beginner to start out with rather than buying scrapers of all sorts? Interesting subject here. Seems that everyone is pleased with this product.

Looking to really do a lot I hand work.

Thanks

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久保
美智え

One is enough until you want to do something that the one you have won't do.
At that point, you might know what you need next. I have two card scrapers, one rectangular, one curved, that did everything I needed until I got the Carruth scraper. It replaced both of them. I can see where I might want the small one in the future, but I don't need it now.

I hate to be so dull (pun intended) but if the belt sander is flat with the platen backing it - then how is the radius made ? From my understanding the round stone of the grinder puts the hollow ground radius on the edge. A belt sander would sander the entire edge evenly, making it flat rather than hollow ground.

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

John A. : Not ideal,but one can make it work. Belt sanders have two round rollers with smaller dia. than most grinders.
Tom

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A person who has never made a mistake has never made anything!!!

Awesome, thanks for the info Bob. I'll be looking to order one soon.

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久保
美智え

I don't see why a hollow grind would be any better in this case than a flat one. In tool sharpening the hollow is mostly there to help you maintain the angle when you're honing. I use a bench grinder to sharpen my scrapers because I have one, and don't have a belt sander. Sometimes, when I want a really fine burr for softwoods or a final surface on a fiddle, I'll lap the faces and then hone the edge on a diamond stone. There's still some hollow left, of course, but the edge itself is flat. Works great.

Old-time carpenters used to just toss a scrap of glass on the floor and use whichever piece was the right shape for a scraper. It's the sharpest possible edge, but, of course, a bit chancy. This is just a steel version of the same thing.

I've got a half dozen different sizes/shapes of scrapers; some thick ones and some thin card scrapers. Some of them are pretty specialized, like the 'hook' scraper used to clean up the sides of a violin scroll. As usual, you tend to do about 90% of your work with 10% of the tools, but that doesn't mean you don't need the other ones once in a while. I only use my spokeshave for neck carving, but I'd hate to make one without it.

Just west of the cow

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

Cool Filippo! My supply of art in that style dried up about thirty years ago, but I still have some around.

i can´t stand more pics of your workshop Filippo, makes me want to have one just like it!

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member of the guild of professional dilettantes

even his glue applicator is clean.

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

What brand of fine grinding wheel are you using to sharpen these, Al? One's in route to the shop now.

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Aaron Craig

Double post.

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Aaron Craig

Then you've never used a sharp scraper.

I use it to level sides, smooth large areas, and more aggressively to refine carves on carved instruments and refine and smooth necks, transitions on heels, volutes, etc. Indispensable tool, IMO, and capable of removing either a tiny amount or a pretty significant amount of wood in an easily controlled, very low risk manner. Plus it's a pretty darn cheap tool.

Plus, it makes shavings, if properly sharpened, not dust.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

I find that I have to be very careful scraping the top with any scraper. Sometimes, the edge will grab, lift, and tear a spruce fiber rather than cut it. The resulting ugliness is hard to deal with. Maybe some of the folks who have mastered scraping spruce could give us some tips?

One of my students had a book on 'how to sharpen everything'. In the section on scrapers he said, flat out, that it was impossible to scrape softwoods. So much for that authority...

The key with any scraper, any time you might hit a soft wood, is a very sharp, light burr. On a card scraper you hone it on a stone, rather than filing, and turn a small burr. On the heavy ones I like to lap the faces to get rid of the existing burr, and then rub the edge on the diamond stone. This gives about as fine a burr as you can get, and, because it's smoother than what comes off the grinder, it tends to last longer.

Other than that, the key to avoiding 'pie crust' edges on the top is to develop your tool chops. If you never hook the top, you won't have the problem. Easier said than done, of course....

Things will be going along great and then I catch just one fiber. The problem with tool chops is that there are so many that you have to have to build instruments. I will try setting up a scraper sharpened as Al describes just for spruce and see what I get. It seems like I'm always learning to sharpen. Conquering one skill just presents the next one to be learned.

Well, I have been following this thread and have decided to add a French Curve Scraper and the two Carruth scrapers. I'm sure this site saves me money, but I know I spend money reading this site!

But time and results are more important. I use my scrapers all the time... and more and more often as time passes. I have this device: http://www.leevalley.com/en/wood/page.a ... &cat=1,310
for those who hate bending a scraper... it works great and I HIGHLY reccomend it. There are so many reasons to use scrapers. One off the top of my head is cleaning glue lines on joined tops and backs before passing through a thickness sander. Just thought I'd throw that in there.

Thanks for all the great info,

Mike

Alan, your stone suggestion was the solution. Wow! I've never been able to get that nice a surface on spruce before. Thank you.