guitar body finish

[Macarel31]

Hi,

I’m building my own guitar and I’m ready for the finish of the guitar body. I want a body stained blue but with natural wood grain visible (it’s in swamp ash). Find here some pictures for examples. I have made some research but I didn’t find exactly what I expected. So I want to have some confirmation that what I planned to do is correct.

As you can see on the pictures, the wood grain is a little black. It seems that before to stain in blue, I have to do something to enhance the visibility of the wood grain. I found different way to do it:

-          Burn the surface of the wood with a blowtorch and sand after until only the grain of the wood grain remains dark. It seems that this is the most used method but for me it seems very aggressive and suitable for failure (wood too much burn)

-          Stain with a dark color and sand after until only the grain of the wood grain remains dark.

-          Use a dark pore filler and sand after until only the grain of the wood grain remains dark. It works with wood which have open pores, which is the case with swamp ash.

Finally, I planed to apply an oil finish (tru oil or Danish oil).

So mow my questions:

1 – Which is the best technique to enhance wood grain visibility

2 – For the oil finish, I find a lot of tutorial but none when the guitar body is previously stained. So is it possible to use an oil finish on a dye?

3 – Swamp ash is wood with open pores. Am I obliged to apply a pore filler? If it’s the case, at what step of my finish process should it be made?

Thank you very much for your answers.

[ADFinlayson]

I'm not a fan of the blow torch idea - may end up cracking end grain. The poor filler is not a good idea either IMO because it will inhibit the blue stain taking to the wood later. If I was doing this, I would stain it black first, sand it back so the stain is in the grain only, then stain blue. If you then apply a heavy first coat of oil and sand it into the body with wet and dry paper, it will slurry up and fill the grain for you. You can do the same technique with wipe on poly to fill the grain if you wanted a harder finish.

[Bizman62]

As you say fire can easily be too aggressive so let's leave that for a future project when you've learned the basics. A dark filler can be used but you don't have to buy it, simply mix dark wood dust with glue and sand it back. Stain won't stick to glue but it doesn't matter if the glue is of a desired colour. The wood dust mix may also take the stain a little better than any plastic based filler.

Any stain can be oiled, that's a common way to do even professionally. Note that the oil will change the colour of the stain somewhat.

@ScottR has a very good grain study including getting the blue right: 

 

[Andyjr1515]

Hi and Welcome!

In terms of Ash, I personally don't use black to tint the darker grain areas - to be honest, the stain will tend to darken this naturally as it will soak in deeper in these areas in any event.

What I personally do is stain it, sand lightly to take the stain off the lighter areas, then re-stain it.  Usually, after about 4 applications the contrast is pretty much the same as the above photos.

I've also done quite a few trials with oil-slurry filling stained woods. 

The slurry-and-buff approach using Tru-oil is well documented and produces a fabulous silky-smooth satin finish:

But because you basically use a wet sanding approach where the wet is tru-oil, and the slurry is the wood dust mixing with the oil, it is usually assumed you can't use the same approach with stained woods.  Surely it will just sand off the stain?

Done carelessly, yes it will.  But it can be done without sanding off the stain.

I use the following regime:

• I stain the wood and let it dry
• I then apply at least two decent coats of tru-oil - allowing to fully dry between each coat
• I then slurry and wipe, using a very fine wet and dry, doing it very gently - I am slurrying the top surface of tru-oil and NOT sanding hard enough to get to the stained wood.  There will be some colour in the slurry, but if I am careful, I never sand the stain off the wood.
• I let this fully dry then repeat 4 or 5 times
• Finally, I repeat, but this time, while it is still wet, I vigorously hand buff it rather than just wipe

These are done that way:

On mahogany -

The dark flecks here are just the red stain soaking in.  Ash does the same which is why I say you do not necessarily have to use black fills. etc..

Incidentally, I gloss then varnished this just using standard polyurethane varnish, wiped on....but it is perfectly playable and durable just oiled like above.  This was after varnishing:

 

 

On maple, stained and oiled only - 

 

I must have a stained ash somewhere - I'll have a search through my past builds

[ADFinlayson]

Wow, love the look of that DC @Andyjr1515 Did you do a build thread for it? 

[Andyjr1515]

3 hours ago, ADFinlayson said:

Wow, love the look of that DC @Andyjr1515 Did you do a build thread for it? 

Probably...knowing me 

The build is actually someone else's.  I bought is as 'built but unfinished' - the price was discounted because the radius of the body sides was not historically accurate.  None of my builds are historically accurate...not even to my own designs...so to me it was too good a deal to pass by.

 

I think I did do a detailed thread of the finishing experiments on it - I'll see if I can find it if anyone's interested.

 

[Andyjr1515]

4 hours ago, ADFinlayson said:

Wow, love the look of that DC @Andyjr1515 Did you do a build thread for it? 

No - I've just looked and I did one on another forum but the photos were on Photobucket before they took all the images off unless you paid them multiple spondoolicks.

 

What I HAVE found though, @Macarel31 , is an example of ash stained in a light colour with no enhancement of the dark grain:

 

You can see here that the dark grain does darken even with such a light stain as this orange ink.  

This was also stained, then tru-oil slurry and wiped as described above.

[ADFinlayson]

4 hours ago, ADFinlayson said:

Wow, love the look of that DC @Andyjr1515 Did you do a build thread for it? 

I'm planning a couple of Gibbo DC style builds myself, just finished making templates and I've been experimenting with finish. This is a mix of Ronseal oil-based varnish, alcohol stain and thinned slightly with whitespirit over a black oil-based grain-filler. Really happy with how it looks considering it's just 2 coats applied with a stiff brush. The only trouble with it is that Ronseal, even thinned, takes a good 12 hours to dry enough to level sand between coats.  I'm planning to try a TV yellow type colour too although I think that will take a lot more coats. Also planning to try tinting brush on lacquer