Aging/yellowing/browning a polyurethane finish

[H K]

You’ll find out once you start stripping it but the red is most likely a tinted or candy clear. That’s typically how Gibson / Epiphone do that color. Also, how their and Fender’s bursts are done. As others have said you might be surprised at how light the “mahogany” body is once stripped. It will probably require some help to look like your second picture. That would also be best achieved with a tinted clear coat. You can try staining or, better, dyeing it but it’s difficult to get all of the sealer out of the wood and even if you do it can take the dye unevenly.

Hmm, yeah.. So maybe the quick and easy is to just use some brownish clear on top of it all? To be honest I was leaning towards stripping, sanding, oiling and waxing, for that nice feel..

Would this affect the weight noticeably too? It's already a bit on the neck-heavy side..

 

[Thumpin6string]

I've been refinishing guitars for 20+ years. There is no way to make the cherry red finish look like walnut other than stripping and refinishing. Take it to a pro. Not any easy refin for the inexperienced.

 

[H K]

I've been refinishing guitars for 20+ years. There is no way to make the cherry red finish look like walnut other than stripping and refinishing. Take it to a pro. Not any easy refin for the inexperienced.

It will be my first guitar job, but I've got some experience.. I do a lot of carpentry, and for years I built custom bikes, including paints etc. Not the same ofcourse, but I wouldnt say I'm inexperienced.

 

[Thumpin6string]

It will be my first guitar job, but I've got some experience.. I do a lot of carpentry, and for years I built custom bikes, including paints etc. Not the same ofcourse, but I wouldnt say I'm inexperienced.

You'd need to get down to bare wood, stain and seal it and then clear it. I only use catalyzed urethanes, so you need the proper compressor, gun, respirator and a decent buffer. If you painted your custom bikes, you should be able to do the refin.

 

[RichterScale]

Adding a brown tinted clear over the existing finish will just obscure the grain more and make it a really dark redish brown.
The old finish needs to come off and unless you sand an obscene amount of material off, you won't get all the sealer/grain filler out of the wood. Staining the wood will look blotchy.
Strip it, sand it, seal it and spray a brown tinted clear.
Finish won't affect the weight enough either way to make a difference.
All the weight is in the liquid media. Once that evaporates, the solids left behind don't weigh enough to bother thinking about.

 

[RichterScale]

Is it a bolt on neck?

 

[Matt Liebenau]

You could try but brown candy on that is probably going to make the finish look like mud. An SG is mostly flat surfaces so sanding the red off isn’t as bad as some others would be, FWIW. It sounds like you might already have a painting process. If not, check out the water based finishes thread.

 

[H K]

Is it a bolt on neck?

This ones a set...

 

[RichterScale]

This ones a set...

That stinks.
It would be fun to leave that body as is and just make a new one.

 

[H K]

That stinks.
It would be fun to leave that body as is and just make a new one.

Or try to buy an unfinished one from Epiphone

 

[Ggaa]

Going way back-to make tinted lacquer we used leather dye(aniline and alcohol then). The stuff labeled 'brown' ended up being a russet color as it built up. To get a truer brown we mixed green and red dyes.

 

[MPU]

My guess is that the bass has thick clear seal coat to fill the pores, then a colour coat and clear coat. That would be the fastest and cheapest way.

 

[dbsfgyd1]

Here are some pics to give an idea of what I want to achieve (more or less)

From thisView attachment 4644829
To more like this
View attachment 4644828

About 20 years of playing smokey dives should fix you up quite nicely. But, when you looking at the effects, remember you’re lungs more than likely are not looking so hot either..LOL.

Best wishes on your project.

 

[tothemax]

Looking at the two finishes, I doubt that it will ever age naturally to anything like the finish you are hoping for. I've owned a number of Epi's and they really go heavy on the poly finish, I've got a LP I bought in 2004 that spends most of it's time hanging on the wall and the finish looks almost new. One thing I haven't seen posted yet is that you could do a test spot under one of the pickups and see what your options are. There's a good chance the routings are unfinished and you can see what the actual grain looks like and do some testing. Granted it's a small area, but it may give you some insight into possibilities. The resale value on Epi's is not the greatest, so you may want to consider that before putting a lot of work into it (don't get me wrong I love my Epi's - I have a LP and a 339).

As an aside: I always keep the stock parts when I upgrade mine in case I decide to trade or sell them. Buyers rarely want to pay for upgraded PU's, etc...

Good luck with your project.

 

[H K]

Looking at the two finishes, I doubt that it will ever age naturally to anything like the finish you are hoping for. I've owned a number of Epi's and they really go heavy on the poly finish, I've got a LP I bought in 2004 that spends most of it's time hanging on the wall and the finish looks almost new. One thing I haven't seen posted yet is that you could do a test spot under one of the pickups and see what your options are. There's a good chance the routings are unfinished and you can see what the actual grain looks like and do some testing. Granted it's a small area, but it may give you some insight into possibilities. The resale value on Epi's is not the greatest, so you may want to consider that before putting a lot of work into it (don't get me wrong I love my Epi's - I have a LP and a 339).

As an aside: I always keep the stock parts when I upgrade mine in case I decide to trade or sell them. Buyers rarely want to pay for upgraded PU's, etc...

Good luck with your project.

Thanks for the advice! As for resale value it doesnt really matter. I was also considering slotting the headstock and putting in the EB3L style tuners, but its a few MM too thin. I might rememdy that tho, idk.
Other than the refinish I'm gonna mod it in other ways, so resale is not somethign I'm concerned about

 

[Ostie]

I certainly wouldn’t leave it outside in the sun. You could leave it indoors in the sun, but I think it would take a long time to achieve the desired effect. Like years, not months or weeks.

I’ve seen older EBs that had chips in the finish and you can see the brown mahogany showing through. A friend has an old EB-0 that someone had stripped, and it is a walnut brown color. I have no idea if the PO applied any brown stain to it. It looks and feels like a Tru-Oil finish.

Stripping the cherry red finish is going to be a pain. I personally prefer the cherry finish, but if you want to put in the hours, it’s your bass.

 

[2F/2F]

With the time you are going to put into that, and not knowing what you are going to get in the end, just buy one from the '70s. A person's time for skilled labor is worth at least $50 an hour. Maybe you are 20 years old and don't realize that yet...but it is. Who knows what that wood will look like afterward. The originals are not expensive, and will do nothing but gain value.

 

[Plain Old Barry]

I'm a big fan of TransTint dyes added to clears. I use a few drops per quart in water based finishes to make them look like aged solvent based products. It will need to be sprayed to look best. A little dye goes a LONG way when making toner.

In the furniture world, we add green dye to clears to tone down reds into browns. You could stain a practice board red and play with green clears on top.

Here's a decent technique to sneak up on the color.

 

[RichterScale]

That's a neat trick to spray a piece of glass with tinted clear to see what it would look like over an existing finish/color.

 

[H K]

With the time you are going to put into that, and not knowing what you are going to get in the end, just buy one from the '70s. A person's time for skilled labor is worth at least $50 an hour. Maybe you are 20 years old and don't realize that yet...but it is. Who knows what that wood will look like afterward. The originals are not expensive, and will do nothing but gain value.

It's about 2500$ for a EB3L... 200$ for a used EB-3. I don't mind the labor of stripping. Hell, I might just do it, soak it in oil and give it a wax. It doesnt need to be perfect. And if I wanna spend my free time doing fun projects like that, who are you to stop me?

I wont do a full refinish though, thats for sure. Maybe a stain and a few clear coats. If I shag it up, I shag it up. No biggie.. Maybe Ill just sand it abit first, and do a slight tint coat or two. That might be all it needs.