Experiments with Tru-oil and Stain

Andyjr1515

Hi

One of the projects I've recently completed - trying to renovate a very old and very falling to pieces bass, involved my normal staining with ink.  The owner wanted orange for the front ash panels and the back - re-panelled in walnut - to coordinate.

However, he wanted an old-look organic-feeling satin finish.  It was just shouting out for the @WezV tru-oil slurry approach.  However, I have always shied away from trying a slurry with stain....for obvious reasons: if you slurry the top of the wood, then you will slurry off the stained timber.

I gave it some thought and tried something out:

• what if I used the Birchwood Casey clear sealer / filler, couple to three decent coats, and let it dry pretty hard....
• ...then slurry not the wood, but the tru-oil filler base and buff as normal?

To my surprise, it worked really well.  Here's the stained walnut:

It's still got that silky 'wood' feel and there was very little lifting of the stain.

I then tried it on the top ash panels.  This had some additional dirtying applied, adding a small amount of dark stain to one of the coats of tru-oil and applying it in normal wear areas, then finishing with a final slurry coat which softened the dirtying and buffed nicely:

It would be a real bonus to be able to use this again in other applications so I'm repeating the experiment with a GSPBasses double cut junior second I bought last year (it was a second because apparently the radius on the edges isn't period correct.  Seems a pretty d****d fine build to me!).  It will be eventually wipe-on gloss finished, but on the road to that point, I will do a slurry/buff stage and see how it does.

I've started it and will let you know how it goes.  From a standard mahogany, I've so far stained it with Diamine 'Wild Strawberry' ink and given it a couple of coats of Birchwood Casey Sealer/Filler:

WezV

Brave move... Sand too far during the slurry process and you wont be able to re-stain.

Results look good though

Andyjr1515

WezV said:

Brave move... Sand too far during the slurry process and you wont be able to re-stain.

Results look good though

Yup - that's why I'd never done it before... 

DartmoorHedgehog

Andyjr1515 said:

One of the projects I've recently completed - trying to renovate a very old and very falling to pieces bass

Bit OT, but what happened with that in the end? I'd be interested to see that - I saw the "before" pictures, then haven't seen any more.  Was there a thread that I missed or did you not post it here?

Andyjr1515

DartmoorHedgehog said:

Andyjr1515 said:

One of the projects I've recently completed - trying to renovate a very old and very falling to pieces bass

Bit OT, but what happened with that in the end? I'd be interested to see that - I saw the "before" pictures, then haven't seen any more.  Was there a thread that I missed or did you not post it here?

Just not got round to it...it was on a very tight deadline but now is finished and passed over to the owner so it is on my overdue list of things to pop a summary thread here 

DartmoorHedgehog

Andyjr1515 said:

DartmoorHedgehog said:

Andyjr1515 said:

One of the projects I've recently completed - trying to renovate a very old and very falling to pieces bass

Bit OT, but what happened with that in the end? I'd be interested to see that - I saw the "before" pictures, then haven't seen any more.  Was there a thread that I missed or did you not post it here?

Just not got round to it...it was on a very tight deadline but now is finished and passed over to the owner so it is on my overdue list of things to pop a summary thread here 

Excellent - look forward to that

Andyjr1515

Found a spare twenty minutes to do the first slurry coat.

I used 400 grit wet and dry, slurried relatively gently, left a few minutes and then lightly buffed off with a micro-fibre:

Although the wet and dry was undoubtedly picking up a little of the colour, there were no signs of breakthrough.

The wiping/buffing cloth again shows a little colour pickup but - bearing in mind this is the full wipe and buff from front, back, sides and neck -  less than I would have thought:

 

I'll let this dry overnight and then repeat another couple of coats, buffing more vigorously after each

Andyjr1515

OK - I've done the second and final slurry and (light) buff and this is done as far as I need to (as explained, I will be actually glossing this with wipe-on varnish and using the work done with the tru-oil as the base coat).

However, as a usable finish, my conclusion is that - with a few provisos - it is a success.

Here are some close up shots:

There are two small patches where it started to lighten or break through - after which I found out how to avoid this:

Here above - on the lower edge in the above picture - the lightening is not grain variation, it is where the stain has been partly removed

Here above - on the edge of the volute, bare mahogany is starting to show.

The technique for avoiding this is to only VERY LIGHTLY buff when the final slurry coat is applied and is still wet.  Then let it fully dry and it can be buffed to a nice satin with low risk of breakthrough.

So final conclusions:

• It is possible to apply the slurry and buff approach with a stained wood
• It will not fill quite to the same extent but you still end up with a silky-smooth organic finish
• It is important to have a harder-than normal base coat over the stained wood.  That's why I used the Birchwood Casey filler sealer and let that fully dry before slurrying with tru-oil
• I used 400 grit for the main slurry and wipe coats (2off)
• I used 800 grit for the final slurry and wipe coat (1 off)
• Everything has to be more gentle than using the technique for unstained wood and particular care at edges and sharp corners.  Gentle slurrying; gentle wiping; very gently buffing while the oil is still wet
• Leave the final satin-ing buff until the oil has dried

By preference for this particular project, I'm now going to carry on and varnish it, but if I had wanted the satin finish, it's basically bare wood to finished playable guitar in 3 days....

...I think I'll be doing this again 

If anyone has a try:

• DON'T blame me if it all goes wrong, but 
• DO let me know how it goes

usedtobe

That looks stunning!

Andyjr1515

usedtobe said:

That looks stunning!

Thanks!   

 I'm quite pleased both with the experiment and with the colour.  

In real life it is very close to the Gibson Wine Red - I used to have a Gibson Studio...guitar was a bit of a donkey but the colour and finish was to die for.  Once this is gloss finished, it will be pretty close, I reckon 

Andyjr1515

Just a post-script.  Applied the first coat of varnish (wiped-on thinned ronseal as usual) to the top and sides:

To be honest, unless I cock up the back, I don't think it needs any more.

Means that the finishing should be all done by the end of tomorrow 

WezV

Looks great

Sarge

Fantastic, good job!
have you varnished over oil before? I only ask as I had not-great results with clear spray acrylic over oil on headstocks and after unscrewing the trc, the cover took a big ole piece of clear with it, just separated from the oil with ease.

Andyjr1515

Sarge said:

Fantastic, good job!
have you varnished over oil before? I only ask as I had not-great results with clear spray acrylic over oil on headstocks and after unscrewing the trc, the cover took a big ole piece of clear with it, just separated from the oil with ease.

Hi, Sarge

Yes - a number of times.  That's one of the reasons I stick to Ronseal Hardglaze (or the Rustins equivalent polyurethane varnish) - it seems to be completely un-reactive with most of the things many other finishes react badly to...

Andyjr1515

WezV said:

Looks great

Thanks, @WezV ;

Sarge

Ok cool.
I have a tin of hardglaze too, what do you use to thin it and is the end result durable?

Andyjr1515

Sarge said:

Ok cool.
I have a tin of hardglaze too, what do you use to thin it and is the end result durable?

This old thread has recently resurrected, @Sarge.  Halfway down Page 4, here, I cover pretty much how I do it.  It's standard white spirits that are used to thin it down.

It's not as tough as a commercially sprayed thick hit it with a sledgehammer modern poly finish, but it's pretty tough stuff.  I've regularly gigged guitars for a number of years without any signs of wear or chipping.

You watch after all I've said - your finish will be the ONE thing it is completely incompatible with 

)

Sarge

thanks Andy

KingNothing

Love the colour, it looks great, I wish I had the nuts to attempt your ink staining.

Andyjr1515

KingNothing said:

Love the colour, it looks great, I wish I had the nuts to attempt your ink staining.

In real life it's actually a much better colour....Canon cameras struggle with reds. If you've seen the Gibson wine red gloss in the flesh, it's a dead ringer I am well chuffed.