Official Luthiers Forum!

I have a 15 year old Warmoth bass that I decided to put new pickups in. While I was at it, I decided to refinish it. The body and neck are ash, with an ebony FB. It was originally finished in just a sealer (clear poly or something).

Well, I sanded it all down to the bare wood. I cleaned it with mineral spirits and wiped it with a tack cloth. I then decided to stain it a dark walnut color. I used Varathane oil stain. The stain went on well. I allowed it a couple of days to dry before proceeding.

I'm a fan of oil finishes. I love the way they look and feel. I did some research and decided to mix up my own concoction of 2 parts boiled linseed oil, 2 parts mineral spirits, and 1 part oil-based polyurethane. The mineral spirits made the mixture quite thin, which I wanted, and I wiped it on with a clean rag, in very thin coats. The first 3 or 4 coats went on great. I wiped it down with 0000 steel wool between coats. It looked great and felt great. Trying to "build" the finish a little, I added a couple of more coats using the same mixture. These last couple of coats simply aren't drying. They've been hanging in my shop, which is in my basement with a dehumidifier running (to keep a 50% RH), for 2 weeks and are still tacky to the touch.

Do I just need to have a little more patience or is my concoction a loser??

In my experience,
if it ain't dry in a day,
it never will.
Start over with Tru oil or something that has been formulated by scientists.
Tung oil is nice too!

You most likely would have been better off using a natural resin like copal or shellac just to name a few rather than the polyurethane. I suspect it only seemed to dry because it was penetrating into the wood. Your mix is also very heavy on linseed oil which can take along time to dry. If it does harden any farther at all the coating will most likely always remain somewhat soft and gummy.

_________________
Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Tru Oil often fails to harden as well. It also is formulated with linseed oil.

I'm with Howard, the linseed oil is what feels gummy. I'd sand it all off and start over. You might have to remove the finish with the mineral spirits first.

_________________
Old growth, shmold growth!

You should have tried watco or a maybe minwax wiping poly. A lot easier then mixing your own. Boiled linseed can take a long time to dry. Two parts seems to be a bit much in my opinion...Mike

_________________
Another day, another dollar.

I've decided to just sand it all off and start over. I think I'm going to try Watco Danish Oil in Medium Walnut. Thanks for the replies.

I've used Watco a lot for woodworking. If you're patient and build up several coats over a couple of weeks, you can achieve a nice warm glow.

After it's cured you can rub it out with rotten stone & a little Watco as a lubricant which will make it shine more. I think the best part is that you can freshen it up later if it gets worn.

Kevin Looker

_________________
I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

Well, I sanded it all off...that was a mess! The gummy finish clogged up my sandpaper pretty quickly. But it's all clean now and I've put about 4 coats of Danish Oil on the body. It looks really good so far. I'm going to take it very slowly applying the finish.

When trying to build the Danish oil, do I just rub it on, let sit for a while, then rub off the excess? Or do I just leave it and not rub it off?

Most finishes like that I apply and let set. I only apply 1 coat every 24 hrs.

_________________
Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Watco is pretty watery, unlike Waterlox which is pretty thick IMO for an "Oil Finish".

With Watco, the first coat I'd flood it pretty thick, wait a few minutes then push it around to re-soak the parts that drink it up.

Then I'd wait about 10 minutes & wipe it as dry as I can.

Subsequent coats won't drink up as much and don't seem to accomplish as much, this is where you need to be patient. Wipe it on, let it set for a 10 minutes, then wipe it off.

I then wait 24 hours before the next application.

After about 4 or 5 coats like that, I let it sit for at least 5 days or until you notice a significant decrease in the stink when you put your nose next to it then I do another coat & sprinkle some rotten stone in with the oil and give it some elbow grease. This will bring up the shine. Then give it a good wipe down to clear off any excess rotten stone. You may need to put some fresh Watco on at this point - it will tend to get dry. The rotten stone has the consistency of ashes. This is the technique I used for woodworking & it always achieved a nice warm soft glow that looked hand made as opposed to a thick plastic coating.

Kevin Looker

_________________
I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.