When to grain fill..advice please

[tls4every1]

Ok so I have my Bulldog LP and working on the mahogany back and neck. Using all StewMac stuff, grain filler, cherry and black water dyes, cherry spray lacquer, clear gloss for the finish. I added black to the grain filler and applied, sanded back, let dry, mixed cherry dye with a couple drops of black and applied. I thought I was ready to spray cherry lacquer but then noticed on Stew Macs nitro cellulose finish schedule that they say do the grain filler after the stain(dye) not before and sand back with 320 grit. At that point I would be worried about sanding too much and taking some of the cherry dye with the grain filler. Any input from you pros is most welcome. I have not reached the point of no return but I don't want to go any farther until I have some advice.
Thanks

 

[jmacscat]

I'm in the midst of finishing a batch of three guitars. I used Stew Mac grain filler with a bit of their colortone stain mixed in, then after sanding with 320 applied two coats of stain(mixed with water) a mix 3 parts tobacco brown to 1 part red mahogany. Good results so far. The application of stain also removed any excess grain fill that was still on the mahogany. I've been using a wipe on poly finish for a more controlled and more durable finish and things are looking good.
Here's a picture showing the stained wood-

[/URL]IMG_0692 by jmacs1959, on Flickr

 

[LtDave32]

Ok so I have my Bulldog LP and working on the mahogany back and neck. Using all StewMac stuff, grain filler, cherry and black water dyes, cherry spray lacquer, clear gloss for the finish. I added black to the grain filler and applied, sanded back, let dry, mixed cherry dye with a couple drops of black and applied. I thought I was ready to spray cherry lacquer but then noticed on Stew Macs nitro cellulose finish schedule that they say do the grain filler after the stain(dye) not before and sand back with 320 grit. At that point I would be worried about sanding too much and taking some of the cherry dye with the grain filler. Any input from you pros is most welcome. I have not reached the point of no return but I don't want to go any farther until I have some advice.
Thanks

There's many ways to do it, but what works for the most of us is to first seal the wood with either vinyl sanding sealer or shellac before grain filling. This enables you to clean the surface wood free of filler, and leave it in the pores where it belongs. You apply the filler with the grain, and remove the excess filler with a swatch of burlap by rubbing across, or at a 45 degree angle from the grain. This helps the grain filler to stay in the pores, as wiping off with the grain tends to pull the filler out of the pores. I might add that both vinyl sealer and shellac make excellent sealers. I use Zinzzer clear shellac, because it's affordable and readily available, and very 'old school".

When you get the filler in, and have cleaned off the excess, sand lightly with 220 paper (you don't really need to go 320) and seal it again. Now it's time to spray your color coat.

You will notice in the days to come after spraying clear coats, that you really haven't filled in ALL of the pores. There will be "shrink-back". This is normal, and doesn't mean you didn't do a good job of grain filling. The purpose of grain filling is really to just cut down the job of clear coating where coverage is concerned. By grain filling, you've simply made the job of "build coats" easier, and are saving $ on lacquer materials. You will still need to put a good 6 coats of clear over the color coat to have enough material on the body to sand back flat, eliminating the pore pits, but not getting into the color coat.

If you don't grain fill, you have that much more clear coats to lay down to achieve the same results.

When you're using a darker color of grain filler than the body color (for contrast), then the purpose of grain filling is two-fold; cosmetic as well as material saving. You are going for that cool "brindled" look.

It sounds like you're taking great care in getting this done right, and looking for satisfying results. That's a great attitude. Be sure to keep us updated when you're ready for color, and clear coating, as we don't want you to make that noob mistake of sanding through the clear. Let us help!

 

[tls4every1]

Thank you all. I will keep slowly forging ahead. I am extremely satisfied with how the flame top turned out, black sanded back and then cherry over the top. I have already put a few coats of clear on that to preserve it while I do the back and neck.
Follow up, do I clean the binding before doing all the clear and spray clear over it or just go clear for everything and then scrap it off the binding at the end? I am not sure if binding should be under the gloss.
I will post pics of the front when I can. Nice thing about the back and neck being solid wood I don't have to worry about sanding through veneer if I make a mistake.