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Hi
I've just completed the first couple of bodying sessions and i've noticed a little gap between the binding and side. It's nothing major but now i've seen it it just won't go away (funny that).
Is it ok to fill the gap with a bit of z-poxy, which is what I used for the pore filling.
I know it's ok to put FP over z-poxy but just checking it's ok the other way around.
Thanks
Mat

Hi Mat,

My experience has been that zpoxy doesnt go to well over shellac. I recently had a few open pores showing after doing a few body sessions over z-poxy on an IRW classical back. Rather than go in with more Z-poxy I filled the pores the old fashioned way using FFFF grade pumice.

MichaelP and other french polish gurus will no doubt be along soon to add their comments.

Cheers Martin

What Martin said - Shellac sticks to epoxy/Z-poxy fine but epoxy/Z-poxy does not stick to shellac well.

Thanks guys - i'm glad I asked.
I could use pumice although I find that quite difficult unless the pores are really shallow. Is there a better option or is pumice the way to go?
Thanks

If no pumice, I would sand down to bare wood on the area close around the gap, also scratch inside the gap with whatever fits in it, fill with epoxy or CA and wood dust etc. I had to sand down to wood several times to fix scratches made by my clumsy thumbnail when rubbing and it blends up just fine.

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Build log

I agree with my buddy Alex.

I have had excellent luck using this method for filling gaps - works like a charm every time for me and is part of my surface prep prior to finishing: http://luthiersforum.3element.com/forum/forum_posts.asp?TID=11580&KW=tutorial#forumTop If your gap is a large gap consider using the method that was discussed in another thread this past week end - heating the area, softening the glue, and reclamping the offending binding into place.

To avoid any mis-match I would sand the top back, fill any gaps, and start over but that is me.

You are probably going to have to sand back anyway, so here is an idea from Robbie O'Brian that I've used on boxes, but not yet on instruments:

Use wet/dry sandpaper and sand back using a 1# cut of shellac as the sanding lubricant. Its kind of like 'super pumice'. It forms a slurry of shellac and sanding 'dust' that does a good job of pore filling. Maybe Robbie will chime in here and explain it better than I can. Its really pretty simple to do.

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Jim Howell
Charlotte, NC

Thanks
I might sand back to the wood Alex, that seems reasonable. It's not a large gap but thanks for the thread Hesh, it'll sure come in handy for other jobs.
I like the sound of the Wet & Dry with shellac also. What grade paper do you recommend.

On boxes, I've used 400 wet/dry to make a reasonable slurry. I sand with the grain and then lightly wipe off with blue paper shop towel across the grain.

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Jim Howell
Charlotte, NC