Adventures in finishing
I often laugh at the term "finishing." In the timeline of a build, the process of final sanding, staining, sealing, grain filling where desired, and top coating, and allowing each of those to dry or cure appropriately begins well before the half-way point, in my estimation. So calling it "finishing" is essentially teasing us, if not outright mocking us.
I thought I knew the drill. "Test everything: Do the whole finishing schedule, sanding through final topcoat polish, on scrap before touching the workpiece." I believed I was doing it right. I have the test pieces to prove it -- a whole library of them. But let's go back to mid-October...
It started with the sanding. Necks and bodies, all sanded through 220 grit, endgrain on the more open-pored woods with 320. Then I applied my stains and dyes. A bit of Waterlox on the Walnut-dominant Nivå body to pop the figuring was lovely. Red dye on Rødvingen looked great on the hackberry top and back, but on the thermally-modified ash on the sides, it did not look great. Something was just off with red dye over that wood hue. So I ran some black dye around the edges and into the roundovers -- too quick a transition to call a burst; more of a very narrow fade. It looked great. For Hammerøks, I tried a 50% diluted water-based amber dye stain on the hackberry. Unlike my test piece done exactly the same way but taken from a different board, this came out far too orange. The stain uptake must have been much more significant or something. So I ended up sanding that back and decided to let the only color come from the dewaxed shellac seal coats and the oil-based poly, thus:
Relearned Lesson 1:
Test your finish schedule on not just the same wood, but also the very same piece of wood that your workpiece came from.
After sanding back and sealing, Hammerøks looked beautiful. I compared my hackberry telecaster look to a coarse-woven linen. Hammerøks, also hackberry but a different board, reminded me, more than anything else, of marble (you can still see a bit of the overbearing "orange" in the deep grain around the bridge area):
So dying and staining were done. Time to do another couple of sealcoats with dewaxed shellac, then grain fill. I had this part down. I've done it on my previous few builds. The shellac would seal the underlying dye/stain layers (one water-soluble, the other oil-based) from any trouble with the water-based Aqua Coat grain filler. I realized my Aqua Coat was almost gone, so ran out and bought another jar. Exactly the same stuff, same label, same size, same spot on the shelf as where I got my first jar. Only one difference: I little red bug on the label noting "Improved formula, now more solids! Fewer coats needed." "Sweet," I thought, but still basically the same stuff -- Water-based over shellac. No problem.
Oh, dear reader. First, Rødvingen. Within a minute of the grain filler hitting the body, the shellac seal coat began to crackle. within the next minute, the red and black dyes were reactivated and pulled into the shellac-grain filler glop. The "new improved formula" apparently dissolved shellac like nothing. So much for my seal coats. The nice red-to-black dyed edge transition became a pink and grey smear. I had a botched dye job underneath an alligator-y, lumpy shellac and grain filler mess. I scraped off as much of the still-wet glop as I could, then set that body aside to dry before attempting further recovery.
I assumed I must have had too thin of a seal coat -- maybe the Aqua Coat got under the sealer somehow and reactivated the dye. At least there's no dye on Hammerøks, so that's not a problem. I told myself. Started grain filling Hammerøks and got much the same thing. Aqua Coat hit the shellac and turned it to goo. Ugh. Scrape off what I can, set aside for later.
I had planned to grain fill the walnut on Nivå as well. Took a look at what I had so far and decided to just let a couple more layers of shellac do whatever pore filling it could and call it good. Walnut grain was tighter than hackberry anyway.
Next day, scraped and sanded everything back until I had a good finishing surface again. I think I did end up with some effective grain filling, albeit with an unholy mix of shellac, Aqua Coat, and dyes. But I got it smooth and (re)finish-ready. I took the opportunity when re-dying the red on Rødvingen to go lighter on the red, let more of the grain show through. So in the end, I got a better finish than the original.
Relearned Lesson 2:
Any "improved" or "reformulated" product is a different product, regardless of branding or label. Re-test everything.
After cleanup and resealing, here is where the thee bodies were:
...And we are now all caught up! Poly coats have been added (General Finishes Arm-R-Seal) and are curing until December 6th.