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I see a lot of builders put shellac around the top while cutting gluing the binding channel, as well as putting shellac around the rosette while cutting/gluing to protect the top.

Question:
Do you actually put shellac in the channel itself - I could swear I've seen this; maybe not?

I'm not sure if the properties of shellac sealing/protecting the wood would prevent the glue (yellow/white/CA) from binding to the wood being glued.

If you do, what is the purpose? I guess I could run some experiments on some 2x4 scraps to test, but if there is experienced reasons, I'd like to hear it.

Steve

CA can stain the spruce, so it's a good idea to seal the channel. For non-structural connections like the rosette or binding, the shellac is not a big deal. It's even a good idea to also seal with shellac before you even cut the channel, it can give you a cleaner edge on your channel.

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Jonathan Kendall, Siloam Springs AR

The reason I do it is because I use CA to glue in my rosettes. If I don't seal, the CA will wick into the top and stain it. If you are not using CA, you probably don't need to worry about this.

Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

I seal heavily the top prior to cutting for the rosette and later for the binding, mostly to keep the spruce clean from the glue squeeze out. I wouldn't put shellac "in" when using regular glues, but for CA it is a good idea indeed. It should prevent the CA from soaking in the endgrain. On the other hand the bond will be good enough. I once glued some struts on the face of a fully polished soundboard and thought it will be very easy to pop them off later, but I was wrong - the CA somewhat cut through the shellac and made a pretty decent bond down to the wood.

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Build log

Thanks for the reply's. I think I'm going to CA the rosette AND binding, so I'll do a good coat of shellac.

I'm just afraid if I use LMI white for the binding (or titebond for that matter), that I'll end up taking to long and not get a good bond - old fingers, lack of experience.

Steve

Jonathan mentioned it, and the others know it too, but I'll restate it, sealing with shellac does one big thing, it hardens the top wood to help prevent chipping out when routing the rosette and purfling / binding channel. There is nothing so discouraging as a chip-out, they are difficult to repair. Do you ever see a guitar with wide purfling? Chip-out cover.

It keeps the top clean too.

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A thin coat is all that's needed Steve.
Just enough to seal the grain.
I use a foam brush ;even though it says on them NOT for shellac or lacquer.

Mike

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Mike Collins

In case of a top sealed with shellac, do you sand it all away before gluing the bridge (in case you glue the bridge before french polishing) or do you glued the bridge on top of the shellac (I am thinking of titebond glue)
Thank you

Yes you need to sand it off in the bridge area. I normally sand all the shellac off on my final sanding before finish. I then mask the bridge and fingerboard area of the top and spray a sealer coat of shellac on the entire guitar before the lacquer coats are applied.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

I know it is a subject for another thread, but I can't imagine doing a decent french polish job around a glued bridge, or fret board.
That would be a skill to learn!

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Not so terrible!

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Waddy

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