Can water based wood dyes be mixed to be more opaque?

Question

I'm working on building a Les Paul style guitar, with a figured maple top, and am just trying to figure out how to do the finish, to achieve a nice sunburst effect.

I lack the equipment and experience to do the finish with an airbrush and tinted lacquer, so I've set my sights on using water based wood dyes to rub on, and then coat with clear aerosol lacquer.

These are the dyes I purchased: https://generalfinishes.com/retail-products/water-base-wood-stains-dyes/waterbase-wood-dye-stains#.Vkn8CK6rRR4

Now, these do a pretty great job, but the one thing they lack is that they are very transparent, which is great for the center of the guitar, but I'd rather have the color thicken up a bit around the edges and get more opaque, hiding the natural wood grain a little bit more.

The General Finishes brochure I had for these dyes stated that they could be mixed with a clear finish to create a "toner". I'm not entirely sure what they mean by "toner" in this case, but I was thinking perhaps this was would be what I was looking for.. But I also don't know which clear finish I would be able to mix it with if so.

The important detail is that whatever I do has to be safe to use the clear lacquer over top. I had thought maybe I could mix the dyes with a bit of polyurethane to do a second coat of color around the edges before the lacquer, but I read that this could cause issues as the lacquer shrinks over time and the poly does not, increasing my risk of chipping.

So I'm looking for some advice on any techniques I can use to get this more opaque coloring around the edges, without removing my ability to lacquer afterwards? Are these dyes even the best choice for me, or is there another better alternative that I can use? (without the need to get an airbrush setup going - or maybe I really do need to do that to get the best finish?)

Answer 1

I lack the equipment and experience to do the finish with an airbrush and tinted lacquer, so I've set my sights on using water based wood dyes to rub on

Let me stop you right there. Believe it or not you've actually set yourself a harder task, where it's more difficult to achieve the result you're aiming for.

You'd want to do some pretty extensive testing to see whether this is even practical for you, much less give you the exact effect you're hoping to achieve. I've used waterbased products of various kinds over the years and even at a far smaller scale than you're working the fast drying time can begin to be an issue. You'd potentially be fighting two things here: evaporation of the water 'base' and absorption by the wood. Combined, the finish can begin to dry in places before you've even completed a single wipe across the area you're coating. And once that happens you can basically say goodbye to any sort of blemish-free application.

If I had to attempt something like this by hand to say that I would prefer to do it with an oil-based product would be a massive understatement.

The General Finishes brochure I had for these dyes stated that they could be mixed with a clear finish to create a "toner".

A toner is one traditional term for a coloured overcoat.

In the past these were more heavily used to blend in (tone) individual panels where the wood was a slightly lighter colour, to match others in a piece that were a bit darker. Or to blend in an unavoidable bit of sapwood to match the heartwood in the rest of the piece.

I had thought maybe I could mix the dyes with a bit of polyurethane to do a second coat of color around the edges before the lacquer, but I read that this could cause issues as the lacquer shrinks over time and the poly does not, increasing my risk of chipping.

This would be highly dependent on what's actually in the can. That advice I'm sure stems from experience using true lacquer, but a spraycan finish that calls itself lacquer might not actually be lacquer in anything but name. There are many confusing and contradictory names in retail finishing products, because the target market is not professionals so they use generic terms as sort of keywords for the buyer, e.g. clear, hard finish = lacquer. Even if what's in the can is a waterbased acrylic finish of some sort.

(without the need to get an airbrush setup going - or maybe I really do need to do that to get the best finish?)

Yes I'm afraid spraying is the way to do this kind of thing. It is possible using hand methods (wiping, padding, flogging, stippling) but it's not an exaggeration to say that reliably achieving a really good result would be expert-level finishing.

Now re. the spraying, an airbrush would not be the tool of choice for work of this scale. It can be done by airbrush (using a suitable nozzle), but some kind of spraygun is better suited to the job and that's what is used in the Gibson factory. Even using the right tool it's still work that requires a deft touch, so a few practice pieces would be advisable to ensure a good result on the completed guitar body.

If you decide to go down this road, be sure to factor in the cost of the compressor and any necessary added parts, e.g. a moisture trap if one is not fitted already. A compressor will usually cost quite a bit more than the airbrush or spraygun so it's not an insignificant part of the setup costs to spray.

Also if you'll be spraying real lacquer you'll want to invest in a good respirator and the appropriate organic-vapour cartridges.

Answer 2

Toner is a colored transparent finish, somewhere between stain and paint in that it sits on top of the wood rather than soaking in. Multiple layers of toner might be a way to deepen the color, at the cost of making the wood grain less visible. I'd experiment on a scrap piece first, of course!