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I'm into my second steel string and still have lots to learn about woodwork basics. I was trying to be much more careful with the little dings and dents to the top etc in the building process but have inadvertently damaged the top a bit while scraping the rosette (3 rings). Damage is around the centre region of the top just below the rosette - obviously where the scraper was just hitting the top against the grain. I have 2 questions:

1. I was using a 2.25" wide scraper with the corners rounded off. Should I be using a narrower scraper, or is it all technique, or lack thereof?

2. Repairing the damage. I have lightly sanded the blemishes, but did not want to get too carried away because conscious of getting too thin in that area. So from some angles it looks ok, but you can feel the depressions with your fingers and can see them from some angles. Should I sand a little more, or hope that the finishing process will resolve it?

When scraping a rosette I always try and have the cabinet scraper at an angle (ie not 90 degrees) to grain and I work in direction of runout. Make sure your scraper has a good edge on it too...you should be producing shavings rather than dust. As for scraper size..I use a full size scraper and keep at least half of the scraper on the soundboard area adjacent to the rosette, IMO this reduces chance of taking the rosette lower than the rest of the soudnboard.kiwigeo39049.2000231482

For me a block of wood and sandpaper is the tool for this job. For just the reason you posted, I don't like scraping on soundboards.
As for your fix: it's not such a good idea to rely on finish to "cover" any mistakes. You'll only make life harder for yourself in the finishing process.

Frank:

It takes a bit of practice to get the feel for it - don't worry, you'll get the hang of it! I also use a full size scraper, freshly sharpened. It is helpful to put a bit of a bend in the scraper as you are using it - thumbs in the center, pulling the edges back with the palms of the hands.   This will help to keep the edges from digging in - this way, you should be able to work the rosette down without digging into the top.

If it's any consolation, I did this on one of mine too!

-Mark

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I can emphasize. I have scraped entire table tops and it does take some practice to get the right edge on the tool and the right technique. If you want to practice, I suggest getting some hard maple or cherry, which are fine grained, and will respond to good cutting of the scraper by producing nice lacy cuttings when you get the edge and angle just right. In the meantime, Paul's technique may be the best!

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I second Mark on bending the scraper so you are focusing the scraping mainly on the rosette. I also scrape mainly parallel to the grain of the top, but holding the scraper at a 45 degree angle to the direction you are scraping. Practice also helps, as Steve mentions.

Gene

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I sand my rosettes, but I do it in the thickness sander. Like Paul I don't like scraping to much on the soundboard. 150 grit and several really light passes through the sander do the trick for me. It takes about 2 min and it comes out perfect every time. If you have a thickness sander I would give it a try. If not Paul's sanding block idea or one of these scraping tecniques should do the trick.

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Do not try to hog the excess purfling/rosette inlay off. Smooth strokes. I don't worry to much about direction till I get the excess near level to the sound board then I work with the grain. If the purfling is very proud of the top it is easer to follow the purfling ring around till near level. This helps avoid purfling pull out if you try to take too much at once. You do want to flex the scraper. As other have mentioned this gives a focused edge to cut with and gets the corners of the scraper up off the top and prevents accidental gouging.

Always start with a reconditioned edge and newly burnished hook. This only takes a minute. and means the world in effort and accuracyMichaelP39049.4844791667

further to the comment above about not relying on finish to hide errors; this may work if you intend to use heavy, matt finish, waterbase, latex house paint.

howver, if your intention is to use any of the more traditional types of guitar finish, they tend to emphasize the dings and scrapes, not hide them. even a burst or a black finish which might cover up cosmetic flaws in the wood wuch as streaks, etc., will still tend to show up your mistakes.

the suggestions given about the maintenance and use of your scraper are good ones. rely on your finish to show off your careful preparation, for it will surely show up your lack of it.

I am with Paul on this, I sand my rosette level and don't use a scraper on soundboards.

How thick is your soundboard and what wood is it?

If you are using say Sitka and are at .115-.125 sand away

Mike

I guess I'm the odd guy out here.
I leave my top a little thick before cutting the channels.
I pre-thin my purfling sandwiches down to around .06" or .05", the same as the pearl or abalone.
Next I inlay everything, and the wood is proud of the inlay. Then it's a simple matter of sanding the wood back to the purfling instead.
Once I have the rosette and wood levelled, any final thicknessing of the top happens to the inside surface.

Call me crazy....

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I seem to be the odd one out when it comes to sanding versus scraping. Ive found with sanding theres a risk of "dirtying up" the top with dust from the darker components of the rosette. This can be minimised by regular brushing away of the sanding dust but my preference is still to use a scraper.

Yea I do like Don most of the time. If need some take down of rosette materials, well like the one today, I use 150 grit on a block about 6" lone and 3" wide for sanding. Go with the grain and can use it wide if needed so not to dig a hole.

The wood is King Billy Pine - used a bit in Australia, but perhaps not available elsewhere - not sure about that.
Thickness at the lowest point is 2.8mm (.110"). Surrounding area is between 2.9 to 3.0mm(.118")

So do you think to sand down to .110" in that area is purshing it?

Frank,

I sand my rosettes, too, partly because I use abalam in them, and it doesn't scrape well. I also do not cut the soundhole out until I am finished sanding, as this gives an even surface on both sides of the rosette.

I also made a partial base out of lexam, with two handles for my laminate trimmer that is even with the bit, and only supports one side of the base. I can cut the rosette and purfling down to about 5 mil before sanding.

Scott

[QUOTE=vandenboom] The wood is King Billy Pine - used a bit in Australia, but perhaps not available elsewhere - not sure about that.
Thickness at the lowest point is 2.8mm (.110"). Surrounding area is between 2.9 to 3.0mm(.118")

So do you think to sand down to .110" in that area is purshing it?[/QUOTE]

Tim Spittle from Australian Tonewoods might be able to answer your question. He supplies KBP and has no doubt worked with the stuff.

Sanding down to 0.110" is getting a bit on the thin side but if youre worried about getting the top too thin you could compensate by gluing a patch in around your soundhole....as is done on some classicals classicals.