I have found this usefull when sanding overlays. Tape a thin Japan spackle on so you do not sand into limb glass.

I do that also, Bue..

What is a Japan spackle 

Stic, it is just a thin steel sheath used to fill holes with plaster.
https://www.jernia.no/oppussing-og-vedlikehold/maling-og-oppussing/maleredskap/sparkler/jordan-japansparkelsett-50-75-100mm/p/32772469?gclid=EAIaIQobChMIxbHRzY2a7wIVFAfmCh1R7wtKEAkYASABEgL1ZfD_BwE

Mike I use a cheap scraper or a thin putty knife.

Bue I have some shim stock left over from years back, Stainless Steel .005 but it heats up fast and want's to burn the glass. so I use a thin putty knife like you. 

Okay I try to get mine mostly thin enough before glue and be sure to wipe the excess.

Same here Mike, makes things so much easier...

  Thanks... Always thought of doing something like that but never tried it... I will try it on my next bow...  I usually put on 2 to 3 pcs. of tape that somewhat protects the glass and tells me when I am sanding too far off course...

How Longcruise makes a bow stringer.

http://www.tradgang.com/tgsmf/index.php?topic=175282.0

I was wondering if anyone could think of a reason this wouldn't be effective for finding and marking the center of the limb instead of a string?  [attachment=1]

That will work fine. Mark it then then swap the other way if the lines cover each other your are fine if they don't the the marker is a little off and center will be between the lines.

I don't use that sort of thing or a string.   If the bow blank has any irregularities they will get transferred as a center line.

I clean up the edges exactly at the fades and measure across the limb to find dead center and mark it.  Do it at both ends of the riser and then connect the two dots and extend those lines out to the limb tips.  If they look wonky it's cause the blank is wonky.  Tape the whole thing first.

I got started with that method when I was very tool and equipment deprived and since it works I keep doing it.  I read here about problems with finding center but I've never had any issues with it.  Strings lay right down the center of the bow.

There are surely better ways to do it but, that's just what my pea brain came up with.   

See, while I was typing Stic showed you a better way.   

I'd still string it. I had one I checked with string awhile back that looked off so I put a 6' straightedge to the sides of limbs and it had a near 1/8" gap at riser.  The center marking gauge won't catch that.

And I have no idea how the limbs were off. One end must have slid sideways a bit...

Hah we sure need no wonkyness 
On a one piece I run the whole bow thru the drum sander to width. Then use a small square and move it until the lines meet in the center. Mark from both sides in case it not perfect. Mark each end and the riser then string check

Drum sander?¿  What is this "drum sander" device?   

I've been using the edge sander to clean up the glue run out, and once I get one side pretty well cleaned up I run it through the drum sander on both sides.  The drum sander was a game changer for me.  I had made one of those little ones with a dc motor and a little sanding drum to try and grind lams, but it didn't work very well.

I do the same thing, I typically make my bows about 1 1/4"- 1 3/8" wide and a drum sander beats replacing blades all the time.

Here is a tip for the salvager's among us. Free Piano's on C-list! Yeah they are big and heavy, but some are made of really nice and exotic wood. Most free ones I have gone to see are veneered, unfortunately!
I'm hoping this one is Maple, with lots of solid pieces and some veneer. Even on cheap pianos, the wood is selected for grain and I can usually mill a lot of lams and maybe a few risers. All the metal recycles, unusable wood gets burned and the keys are so easy to give away, I'm thinking they must be valuable. If your lucky and find an old one, on some the black keys are Ebony.
I can only take them if they can be rolled and no Grand or Baby Grand's!  Which is unfortunate because they have the nicest wood
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