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I use an oscillating spindle sander to shape my pegheads. The curves along the side of the headstock typically have a bit of a wave from the spindle as you run your finger along side them.

I tried to smooth them by running the curved face of a rasp along them like a spokeshave or place, and it was effective, but only to a limited degree. They're very minor, but I'd love to know of effective ways to smooth them, excluding using a routing or sanding template. I can certainly use a template next time, but obviously not on this one.

James,
I've achieved good results using card scrapers.

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George :-)

How tight are the curves? Have you tried adhesive-backed sandpaper on a section of dowel or PVC pipe? I use dowels of a few different diameters as sanding blocks for things with tight radii. If the radius is larger, PVC pipe or thick-walled cardboard tubes work.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

The curves aren't super tight. The curves along the top and bottom are great. It's the sides I seem to get slight waviness in.

Small hand plane for a coupla passes???

A hard block with a bit of a radius. 80 grit and a bit of elbow grease should do it.

Thanks for the buffs James. That worked out well and a lot less $$$.

+1 If you draw the card scraper at an angle, it won't follow the peaks and valleys from the spindle sander as much.

Alex

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

I usually shape first with a chisel, then with a file, and then scrape. Change angle frequently with the scraper to avoid developing ripples. The sides of the headstock may end up somewhat convex rather than perfectly flat, but I like that.

If you still have trouble, a curved hard sanding block is the most reliable way to eliminate ripples.

Some shim stock and PSA sandpaper should work fine in the right thickness

Brent

3mm Perspex, 120 grit paper. This will bend to smooth most curves on a guitar. I use a piece 600mm x 100mm when flattening sides prior to routing binding channels. A smaller (thinner?) piece will do for headstock curves. If the lumps are due to grain lines, you'll need to use an edge tool, as the early wood will sand faster than the late wood.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

I like the spindle sander. Just use the largest diameter spindle that will fit the curve, feel the area and put a pencil mark where you feel bumps and with very light pressure take them off with the sander.

From there hand sand with a curved block of wood with some paper stuck to it. It goes fast and easy.

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Joe Beaver
Maker of Sawdust

Mr. Gore's notion is similar to our approach, but we start with a small (6"), flat bastard file to plane the high spots away (as mill bastards will do with little in the way of file marks when oriented correctly), then finish up with P150 and P220 on .090" 3/4" x 4" Lexan scrap with the long axis aligned with the head stock. This technique keeps things flat and square, and works even on long concave curves. We also find the smaller mill bastard files to be very handy, and they can be easily and quickly ground to safe edge - we have them down to 3" length, which are very good for working superglue fills to level before final scraping and sanding.

I never realized how essential a good handle is to proper use of a file or rasp until I started in this shop - all of the files have the appropriate size of Lutz Skroo-Zon internally threaded handle (or other quality brand), which - in addition to being an important 'safety of use' requirement to avoid being punctured by the sharp tang - helps maintain file orientation square to the work. US-made as well, from US and Canadian birch, so both quality and good price from the same tool. Prices vary widely - some specialty shops charge $8 or more, but Betty Mills (a janitorial and industrial supply company) usually has good prices in the $3-$4 range (depending on size) and runs nearly constant discount coupons for larger orders.

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A constellation only takes shape when one maps the whole.
- Beth Brower

Don't run your finger along it.

I've never had any luck fairing out that waviness with curved sanding blocks or a scraper because they like to ride in the dips. So I use a short flat sanding block with some 80 grit paper and the waviness disappears quickly.

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

I use hard rubber drafting erasers and work up through the grits for final cleanup on headstocks. Similar to Ken's approach although the erasers provide a bit of flex.

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Steve Smith
"Music is what feelings sound like"

Thanks, guys! I almost decided not to post this because it seemed silly. The lexan/perspex with sandpaper sounds perfect.

If it's a concave curve I need to sand more than once, I make a sanding block that's a convex counterpart to the concave curve. The convex curve on the sanding block is easier for me to get right than the concave curve.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

If I have to sand a curve I always use thin styrene plastic and stick-it paper. I have sheets of 1/8" styrene that use for all sorts of things like shim stock, templates, and custom sanding blocks. It cuts easily by scoring it with an X-acto blade and then snap it along the line.

It will conform to most curves on a guitar and give you a nice smooth finish when you are done.

Bob

Similar to Trevor, Bob, and Woodie, I use thin plastic with sandpaper glued to it. This is what I use to smooth the sides as well. Since I don't have scraps of Lexan or Styrene, I use scraps of Formica countertop laminate (I think this is phenolic laminated with kraft paper), which I thin by feeding through my thickness sander so it feels right for the particular curve. Currently I have a thicker and thinner piece, and those two are enough for all the curves I sand.

The plastic is hard enough that I don't have a problem with soft grain being sanded deeper than hard grain.

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Tim Allen
"Never hurry, never rest."