I've begun finishing work. I chose epoxy again for grain/pore filling. This time, however, I'm using the proper epoxy and the proper procedure. I ordered Pacer's Z-poxy finishing resin. Normally reserved for fiberglassing, this epoxy is much less viscous and has a longer open time (20-30 minutes) than the 5 minute Loctite I used before. The procedure was determined through research on luthier forums and a few youtube videos (mainly, this 3 part series: Epoxy Pore Filling Part 1). One big difference in procedure from my first attempt is to build the epoxy up beyond the surface of the wood, resulting in a thin film. The lacquer will then be laid atop. The result should be a perfect glass-smooth finish, without any wood grain showing as pits on the surface.
Step one, prepare the wood. The acetone I used to strip the existing lacquer left a thin film of finish on the surface that needed to be removed. I started with 180 grit sandpaper and continued to 400 grit, followed by a wipe down of naphtha. Some of the binding needed attention. Removing the old binding tore some walnut wood out, most of which I've touched up before adhering the new. However, some spots got filled with binding glue and now look awful.
The binding on the left has been untouched, while the right side has had its walnut/binding seam scraped. You can see the bottom left binding with a little filling of glue. I used an X-acto knife as a scraper and 'picked' out the glue mess-ups.
I planned ahead and applied the black dye to the headstock before I seal it with epoxy. Letting the dye 'cure' for a few days will prevent any dye from smearing during sealing.
I built this stand for the guitar to elevate it off of the table for sealing. This allows me to epoxy the back, top, and sides of the guitar at once without waiting for one section to cure.
It's very well balanced. The back end of the guitar has a screw set in the strap hole which sits on the support.
The fretboard has been taped off, only to see the light of day once the finish is complete. The wood is sanded and waiting for epoxy.
Mix ratios are important, as improper mixing can result in uncured resin/hardener left on the surface or an improper cure in general. I am using a little medicine cup for mixing. My batches are very small so it is difficult to get the ratio right. I will eventually invest in a gram scale for precise measuring. This is difficult to find in a store due to the usual market being 'drug-people'. I got a couple funny looks in the UPS store for asking. My best chance would be to order online. Meanwhile, my spoon method seems to work fine.
After mixing, briefly heat surface with magic heat dispenser.
And then...do it. Sorry I couldn't take any pictures during the process, but it only involved pouring a little epoxy on and squeegee-ing it over the surface. After full coverage, squeegee off any excess and remove any drips from the edge.
Once I get one coat over the entire guitar, I will use the stand I built. For some dumb reason I flipped this image around.
The grain looks great. Further coats of epoxy will make it look more gooder. Yes, more gooder indeed.
Sides will be done next.
I've done a few test pieces, and the first coat merely seals the pores, while the later coats fill up the grain. This shows the guitar top and the sealed surface.
New updates will probably include the result of sanding level the surface after all coats of epoxy have been applied.
-APB
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