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We all at time have to fill small gaps with wood dust. with dark colored wood this is not a difficult task but with light color woods like Maple and especially spruce I can never get it done to satisfaction. When the dust is flooded with CA it darkens. this is an area I could use some guidance in. any suggestions?MichaelP38383.528287037

I need the same help!    But with mahogany and cedar.

Awaiting the experts advice...

Eric

Guys, I think you'll always be better off to make a very small graft. Slice a thin diamond shape valley and make a matching "plug" of matching grain wood. That way you'll only have the slight seams of the diamond to have to hide.
If that doesn't fit your bill, you might try making a putty of white glue (LMI) and matching sawdust. Then push it into the gap. That will not darken as much as the CA route but might still be off in color.

Here's a trick I found by accident...

I routed out an inlay piece and as usual I left a couple of canyons on the sides in a couple of spots (I hate when that happens )..

I knew it was going to show and was killing me so out of frustrating I shaved off some of the same woode in very thin strips and with some tweazers and dental tips forced the wood into the voids. Once I had them all full I smacked them with a dab of good clear thin CA glue. When I sanded back down they basically disappeared.

Now it took me probably 20 minutes of fidgeting to get it right but it was worth the effort (and I taught myself some new cuss words as well... Bonus!!). Now On lighter wood Paul is right that LMI instrument glue would not darken as much, however because I was not using end grain or wood dust it barely darkened at all..

Cheers

-Paul-

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-Paul-

Patriot Guitars

Michael--there is no more difficult problem that hiding a gap in spruce. I've tried and tried. My conclusions were first--as has been said--rule out CA. It just darkens way too much. A white glue is better. Then, since the glue will darken your mix some, you need a lighter dust than the wood you are using. A little experimentation is in order. Get a scrap of your spruce, put some purposeful dings in it, and experiment with different fills. Let them dry to see the final color. You could try some really white Engelmann dust for a Sitka fill. Maybe. I've used things like baking soda and ginger to come close to matching the color. And when you've finally got a color match, it will be invisible from one direction only. There will be no refractive quality to the fill. When the top is moved in another direction, the invisible repair will show. Arrrrggggghhh!!! But, if your problem isn't great, this might be a useful compromise.

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From Nacogdoches...the oldest town in Texas.

http://www.stephenkinnaird.com

[QUOTE=Sprockett] I knew it was going to show and was killing me. So out of frustration I shaved off some of the same wood in very thin strips and with some tweazers and dental tips forced the wood into the voids. Once I had them all full I smacked them with a dab of good clear thin CA glue. When I sanded back down they basically disappeared.[/QUOTE]

My only experience with CA was building RC model airplanes of balsa wood. Seemed like the CA hardened on the wood and then it didn't sand down at the same rate as the bare wood. Won't this happen on the topwood if CA wicks into the endgrain, say around the rosette? Can you then sand down the excess CA evenly with the spruce or cedar? And will it really be invisible?    

And what CA brands and consistency do you all prefer? I haven't bought any in about 8-9 years.

Thanks,

Eric

I think most people seal the top with shellac (or something similar) to prevent CA from wicking into the top. It can cause discoloration.

I prefer starbond CA. I think it is about the best stuff going, but others buy no name brands from the hardware store... so you probably need to find what works for you.

When sanding, if you are working on a flat surface take a longer flat sanding block and sand across both harder and softer surfaces. You can generally minimize the effect of the paper creating shallows in areas that are softer by using a longer block. Just make sure it is really flat.

bpoling38384.369375

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

I have had the same problems with tops as the rest of you. I think the "shaving" or "whole wood" repair is best. Dust just doesn't work for tops. as for other woods...It depends on the wood. I found that cracks in Bubinga(and most colored woods - not Western Cypress) disapear with CA while voids around inlay (like logos) darken. So as others have stated the "chip" or lighter dust with LMI white glue is the only resolve. I have tried the laquer sticks but find them difficult to work with and rarely get an exact match. We all see how nice rosewood and ebony turn out. Palo Escrito isn't too bad. I have had good results with Cocobolo although it does darken some as well. FORGET about maple! Throw it away and start over...I tried everthing and just couldn't get a satisfactory match. Has anyone tried using hot hide glue? I bet Dan Erlewhine, Don McRostie or Frank Ford could get theirs to match...but hey...what can't those guys do?

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Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"