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I was working on the figured walnut back on an octave mandolin I'm working on, with scrapers, and was getting frustrated by how little progress I was making with them (my thumbs weren't feeling too good either) I then caught sight of a "french curve" scraper I bought along with the rest of the little buggers and thought "Hmm, maybe that curve would cut a wee bit better". There was no comparison. I scraped that back lightly and gently and got SHAVINGS! SHAVINGS I SAY! With the flat scrapers I got itty bitty shavings but they were mostly just scrapings, and they took a lot of effort to get. With the curved scraper, I freaking HOGGED that back into submission. I was willing before to just flatten the back and leave all the tiny gouges and tearout because it was just going to be too much work. Now I have a resonant, imperfection free, back that is going to work optimally. I will never waste my time with square scrapers again. Curved is the way to go.

For bindings and other delicate work, I do recommend using a square scraper. Get a thinner, more flexible one and you will be able to make more progress on it, but all the while being more gentle in that area. The french curve that I have is far too aggressive for that sort of work.

Epiphany not with standing your success with the curved scraper has nothing to do with the shape of the scraper.
To start, how aggressively a scraper cuts has to do with how big a hook you put on it. You can put a large or small hook on a thin scraper as well as a thick one. It is easier to put a hook on a thin scraper because there is less metal to move. By easier I don't mean that the hook has more quality, just easier to roll a hook. Because of this it is easier to hook a poorly prepared thin scraper than a thick one. There is also the tendency to over hook a thin scraper.
Any scraper can easily pull nice shavings if tuned properly, regardless of it's shape. A curved scrapers purpose is to get to areas that can't be reached by another shape.

FWIW my favorite scraper and the one I use 20 to 1 over others is a 1/16" thick 2"x6" piece of old band saw blade. The reason I like it so much is that it doesn't flex at all or very, very little. I can scrape and keep things flat with no danger of creating hollows or over scraping. I wouldn't give up on your rectangular scrapers just yet.

L.

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Cut to size.....Beat to fit.....Paint to match.

Besides the curved one being sharper, I think the shape does contribute - in my experience, if you flex a straight scraper more, it will take a heavier cut.

Kevin Looker

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

I've been working with scrapers pretty consistently for a few years now. They've always been one of my favorite tools. I have been able to get shavings like the ones on my french curve on occasion after spending some quality time with it, but the difference between even my best job burnishing the flatty and the small effort I made on the curve is dramatic. Something about that curve just loves to take away large amounts of wood from the plate, so that's what I'll use to do that. There might be other factors contributing to my success, but success isn't something I tend to disregard just because I'm told I'm not supposed to be successful

How are you relating a curved scraper to a straight one that is flexed. I don't see the relationship.

As a scraper dulls you have to flex it more. By flexing it you concentrate the pressure on a smaller area. It has the effect of pushing harder. However you shouldn't need to push hard, that makes you lose control and control is one of the benefits of a scraper. Tuned well it takes very little effort to take big shavings with any scraper. A slight flexing is helpful to keep the edges of the scraper from digging in or making marks where you don't want them.
Again the purpose of curved and variously shaped scrapers in not for a deeper cut. The deep of cut has to do with the size of the hook, the angle you hold the scraper, how hard and where you apply pressure, the type of wood etc. If you want to hog off a lot of material a thick scraper is a much better tool. This assumes proper tuning. Another bonus is your fingers don't get hot and you keep things flat. With a thicker scraper you can roll a larger hook and have it be supported. You roll too big a hook on a thin scraper and it won't last but a few cuts. How hard a scraper is, that is the metals hardness is a factor as well.
A simple tool but one with a lot of nuances. Well worth the effort to master.
L.

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Cut to size.....Beat to fit.....Paint to match.

Ya know, for a guy who worked with cutting tools of all kinds my entire working life - I can't sharpen a cabinet scraper well to save my life. I don't know what I'm doing wrong. But - boy, they work good when they're sharp!

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"Act your age, not your shoe size" - Prince

Me only 26 years.



No one said you weren't supposed to be successful or to disregard your success. It is just your conclusions are inaccurate. You could be getting a lot more out of your straight scrapers. You don't have to believe it or change, I don't care. I do care when information gets thrown out that could mislead someone. When you make a strong statement of a "Epiphany" and "throwing out" your other scrapers, and your analysis is not complete and or not quite the whole story, well it begs a comment. I assume you expected some kind of response to your thread.
A analogy (not to the scrapers but the logic) might be if you had a Yugo and a BMW. The BMW isn't tuned up well and is only running on 3 cylinders but the Yugo is tuned up well. You drive both and because you can only go 30mph in the BMW you conclude that the Yugo is a much better car is smoother , faster and just much better.
You could add that it suits your needs and you a delighted to be driving this car after the BMW. Then someone comes along and rains on your parade by saying , you know if you tuned that BMW up well it would work even better for you..........
You can still drive the Yugo, (maybe better mileage or it is smaller and will fit into parking spaces the BMW can't) but if you want the chicks, ........ well.
OK so I got a little carried away with my lose analogy. Anyway, that is my point.
L.

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Cut to size.....Beat to fit.....Paint to match.

If the end result is desired and indistinguisheable from the correct methodology, what's the difference?

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Old growth, shmold growth!

This is getting ridiculous. I highly doubt whether someone could keep a panel flat with a curved scraper. At least easily.
There is no " correct methodology" nor am I claiming such.
If you cut your dovetails with a sharpened screw driver and claimed a epiphany because you didn't or couldn't sharpen sharpen a chisel and someone told you about using and sharpening chisels you could easily make the same statement you made above. But you wouldn't learn anything and you might not find a method that worked even better.

And to answer the question directly, The difference is in speed and accuracy and ease. And It may not be indistinguishable and to the point and not your question, because the original information is misleading.
L.

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Cut to size.....Beat to fit.....Paint to match.

I see where you're coming from man. You've been at this for a very long time. You have a passion in getting the best out of your tools and then some newbie comes along and pretty much says (indirectly of course) that your research and efforts have been all for not. I'm sorry you feel this way. Here's where I'm coming from. I love the concept of this tool and the desired result is something I would like nothing more than to get. I've been practicing, researching, and using the things for a while and I'm getting better at using and maintaining the tools. One night I'm trying to do something and it's taking me a discouragingly long time to do. My fingers are black and calloused, as well as sore and the burning from scraping isn't helping. I then try something else "just for the heck of it" and it works so well I'm inspired to share it with other people who might want to know about it. I might not have thought my words through, that's bound to happen when one is excited, so I'm sorry if I offended you, because it seems to me that I have. You have, however, inspired me to rethink my techniques and try to get the flattys to work. If you swear by them this much, with all your experience to back it up, I'm clearly missing something big.

Ian, Don't throw out the curved scraper either ! In fact for me I find it a bit harder to tune up one of those more so than the straight.
I am not upset, just offering my advise. You might hog with the curved and when you are close use a straight. The curved are usually fairly thin and as such won't hold up to hogging like a thicker one. You can keep using a different section though and off set this. You can also grind a slight concavity or convex-ity (not a word I know) to any scraper for different things. A thicker curved scraper might be just what you would want. With any of these it makes a world of difference if they are tuned well.
No need for burned fingers.
What we have been talking about are "Card scrapers" One of the best tools I use and one of the most underrated is the "Cabinet scraper" This, as you might already know is the spoke shave like thing that holds a scraper blade. Get one of these tuned up and you can flatten a panel in no time at all. I used to challenge people to races, me with the cabinet scrapers and they with their belt sanders. No contest. The beauty of the cabinet scraper is the sole gives you stability and really helps to keep things flat and no hot fingers ! Of course if you have a thickness sander.......

Just got your pm, will be in touch.
L.

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Cut to size.....Beat to fit.....Paint to match.

Link, you missed the point. He wasn't talking about a flat panel, he was talking about a mandolin back, which was most likely arched, but even if not, he stated that he got the job done faster, and more accurately.

The curved scraper worked better for this task, and you jumped all down his throat with your superior knowledge.

In this case, the curved scraper was better than the flat one.

Quite frankly, a flat scraper probably wouldn't have worked as well.

Also, in this case, your analogies are completely wrong. He wasn't using improperly tuned tools, he has plenty of experience with scrapers, nor was he using an incorrect tool for the task and calling it better.

Ian, you're on the right track, not that you need me to tell you that.



So, if the result is identical yet faster, so what if he used a curved scraper?

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Old growth, shmold growth!

Haha, no, the curved scraper stays too, and I'll be using it WAY more often now, no question about that. It is quite thick, probably the thickest I have by a small bit. I knew from the start that that is what attributed to the aggressive cuts I was getting, seems very easy to get it sharp again, as I had to reburnish it twice that night to keep up the progress I was making. I am in no way intending to do anything as big as a cabinet, or anything much larger than a guitar really, so I think I've about got what I need in this particular department for now.

Hey, just curious, but how long does a well sharpened scraper last for you guys? It is certainly one of my favorite tools, but it's an awful lot of work keeping it pulling more than a tiny fluff of dust per stroke. Usually I'll get it all nice and hooked, and makes quick work of things, pulling good solid shavings. Then after 10 or 20 strokes, I'm back to dust again. Then I switch from flexing and pushing with the middle, to pushing more with the corner (which I have rounded over to avoid scratching), and that gets some good shavings for a while, then switch to the other corner, then repeat the process on the other side, and then resharpen.

I guess it's not too bad, but it sure would be nice if I could stick with the flex and push with the middle style, until my arms get tired.

I don't mind you last post except your aggressive b.s. about the jumping down someones throat part.
Thanks, I'm glad you think my knowledge is superior. I would say it is pretty well informed but you have a right to your opinion. I responded to his post, I don't remember jumping down anywhere. Ian didn't take it the wrong way and we are cool, so you could chill as well.
About missing the point, this is where you have demonstrated superiority.
Read the original post. He said he wasn't getting shavings from his flat scrapers, (news flash, that means they are not tuned properly because you can get nice big shavings from any type of scraper) not that he couldn't get them to work on a curved surface or that curved scrapers work better on curved surfaces. He stated that they weren't worth keeping and said because they would take a decent shaving. There was some misinformation put out. I was taking his points about using scrapers in general and addressing that.
I know how he was using them and what for.
I hope he doesn't take your righteous efforts to defend him as patronizing.
I had no bad intentions with my response nor was I trying to tout my knowledge ,( whether it be well informed as I contend or superior as you say.) I was trying to impart some information.
You got a problem with that, I can't help that.

L.

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Cut to size.....Beat to fit.....Paint to match.

Link now you see why a bunch of us don't post much anymore. Experience doesn't count and if make statements some are considered being superior. I want one of your fly boxes

With flies too ????

Link

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Cut to size.....Beat to fit.....Paint to match.

Hey Ian,
Thanks for being open enough to hear what I was saying. I was not upset with you by the way. Maybe a few of the others though
I can tell you how I tune them but a lot of that is already out there but I will if you want.
What I was talking about is no way limited to furniture or cabinets. A few nights ago I had glued my bindings on a guitar and had left them way too thick and tall. I left myself with a lot of hard work. I tuned up my trusty thick 2"x6" scraper and started wailing away. I was getting huge shavings but more importantly there was no danger of over cutting with the straight scraper. Once I was close I could rest the whole edge of the scraper on the side of the guitar spanning both bindings if you know what I mean. I could still be pretty aggressive but not really risk cutting too far or getting anything out of flat. You end up with perfectly flat and true sides from binding to binding. This worked well on the top and back as well.
Again, what ever you use is fine but your success with the curved and lack of success with a straight isn't proof of the straights limitations. That is what I objected to and how this might keep someone else from learning about tuning a scraper if the minute they had a bit of trouble they concluded that straight scrapers are no good. Then they read that they are not worth keeping and........ I mean if you said, boy those curved scrapers sure work well, they really can hog. I would not have responded, or I might have said I know what you mean. But when you said you were throwing the straights away, there by pretty much saying they are no good, I had to cry , operator error. It wasn't a attack on your personally. (I know you know this, I am saying this for others )
Ian, I'll make you a deal. Just by coincidence I am making a few thick scrapers. 1/16" x 2"x 6" I will send you one, tuned up and you can have it, try it and see how you like it. If you don't like it send it back but I bet you will be pretty happy with it and find many uses for it. You may still use your curve one a lot but I bet you will have a new "epiphany" about straight well tuned scrapers. Well, , maybe not a epiphany but you'll like it !
L.
Link

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Cut to size.....Beat to fit.....Paint to match.

I sure hope we don't lose another contributor to this thread

Link was right in saying that I was making a statement that flat scrapers are inferior to curved scrapers. He's also right in saying that my scrapers weren't being worked properly. I doubt ANYONE on this forum knows my burnishing process or the tools I use to do it. The assumption that I might not be doing it correctly is the correct one with the information given. The back to this instrument is flat. Not sure if I wrote that down anywhere. I'm 100% sure that we wouldn't be having this conversation if I was using a card scraper to do an arched back anyway because that's a bit hard to do now isn't it!

And with a curved scraper, you also concentrate the pressure on a smaller area, that is the relationship, not to mention that by flexing a scraper the cutting edge is no longer a straight line but a curve.

Kevin Looker

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

FWIW
Ian, I use the usual procedures. I used to use a draw file. I don't know if you have one but they have the teeth at a 45° to the edge of the file. You can hold the file perpendicular to the the scraper edge and draw towards you, or away from you. This is really good for curved scrapers ! This works pretty well on the straights but recently I have been using a guide and a regular mill bastard file. If I do a good job filing (a little chalk on the file keeps the filings from rolling up and spoiling the edge) and I am not going for the best edge I will use the edge right off of the file. I of course lap the sides with the 8000 stone after filing. If I want the best edge I use a diamond stone. I made a guide of 1 1/4" wood. It holds the stone at a perfect 90° to the flat surface of the wood and I can lay the scraper flat and hone a perfect 90° with that. (Yes I have gotten lazy in my old age.) Again I polish the flat sides of the scraper. With a round burnisher, (I like the Hock) and a little oil to lubricate things I will first make some firm strokes with the burnisher 90° to the scraper edge. Then I will gradually angle the burnisher to about , humm, I'm not sure, I just do it by feel. Maybe 10°. I do this for both edges. I feel for the hook and this informs my pressure and angle. Then I will lay the scraper on it's side and burnish the hook off so I can't feel it any more. Then go back to the process as when I first put the hook on. This double pulling of the hook is supposed to work harden the edge and it does seem to work. I think it more important with softer steel. I have some harder scrapers where I don't think it matters. The better the edge before rolling the hook, the better the end result. That is a perfectly smooth polished 90° edge will give you the longest lasting, sharpest hook. This is pretty much what most folks do with different preferences for burnishers, stones etc.
Just like guitar building the devil is in the details. It's funny how it seems like the more simple the tool the more nuances there are.
Link

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Cut to size.....Beat to fit.....Paint to match.

Kevin, I see what you mean and I agree. I will say then that there are two ways to get a heavier shaving. One is to increase pressure and the other is to have a larger hook.
The trouble with more pressure is faster degradation of the edge, loss of control, more chance of chattering and tear out, hot fingers !
The loss of control is from that curved edge making low spots if you aren't very careful. And what I was trying to say was that it is better to rely on a sharp well tuned edge than extra pressure. I was trying to talk in fairly general terms to not obfuscate the main points, or should I say my main points. I am not sure if everyone knows how easy it is to use a well sharpened scraper. It is like the difference in having to push and fight a hand plane with a dull iron and the ease of a well tuned sharpened one.
So I wanted to get that across. Also, I will say again it is helpful to have a thicker scraper to support a larger hook.
L.

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Cut to size.....Beat to fit.....Paint to match.

Here's a tool available through Lee Valley that I like for preparing scrapers.
http://www.leevalley.com/US/wood/page.a ... 3072,43089
If you read the description you'll get the idea of how it's used. I use it to get the edge straight (on a straight scraper obviously); I follow this with micro abrasives on a granite plate to clean up the file marks and then draw the hook with the burnisher.
I hope this info helps some of you having problems with your scrapers...
regards
pvg

You said my comment was ridiculous, I figured you were ridiculing me, and that made me think you were ridiculing Ian as well. I considered that to be aggressive BS, my friend. Ian is taking it well and being polite. That means he's a nice guy. It doesn't mean you couldn't have been a little more tactful. I'm not patronizing Ian, I actually know some of his family personally, and have a high opinion of him as an intelligent articulate human being, and I wouldn't just assume that because he wasn't getting the desired result he was doing something wrong. Maybe for figured woods, even on a flat back, the curved scraper is better, maybe not. The determinant factor is the result, which Ian says is adequate. I'm assuming his scraper was probably set up properly, and he got better results with the curved one on this instance. I could be wrong, but I won't just assume. I've had times where a perfectly good scraper got poor results, even though it immediately got good resultson a different wood for comparison.
Ian, if he leaves because of a comment I made, that shows he can call people ridiculous, but can't recieve criticism either. My thinking is he'll stick around.
I don't appreciate being insulted though.

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Old growth, shmold growth!

I quote myself : This is getting ridiculous is not saying your comment is ridiculous. The situation is getting ridiculous, as in getting off point and getting on a high horse and defensive. Making assumptions about what I was saying and somehow construing it to mean I was slighting you or someone else.
I am glad you have admitted that your post was not on point but a attempt to defend a perceived slight. This has apprently made you unable to interpet what you have read. He said he wasn't getting shavings, just crumbs and dust. Hello, no assumtion needed, it was there in black and white. You are the one who has made assumptions.
I try to stay out of these "ridiculous" things but somehow I let myself get sucked in. My interactions with Ian were constructive, my interactions with you, a waste of time.
I am done with you and this thread.

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Cut to size.....Beat to fit.....Paint to match.