Official Luthiers Forum!

Michael
Sorry, I don't mean to hijack this thread but...
I have come to the conclusion that french polish is the finish for me...it is the method I get the best results from. But...I have not used walnut oil. My question is, will walnut oil tint the shellac in any way? It is my assumption that it will darken the shellac...but having never used it, I don't know that to be the case.
Can you tell, in your experience if walnut oil changes the color?
Personally I am a big fan of the clear amber shellac flakes from LMI.
David

No it will not tint the shellac. noticably anyway. Rememer the oil rises to the top of the shellac and is removed with each spiriting off session. it does not congell with the shellac. It is constantly pushing ahead of your padding during boding. If it does not say 100% pure and if you are paying less than $2.00-$3.00 per oz then I migh question its purity.

One more question and then I will not interupt this thread again. Do you spirit off after each session? I have only spirited off after all sessions were complete.
David

Yes!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! After the second body session and every session thereafter. Do so and soon you will find you never need to sand the film level because you level as you go. Now to honest it takes some experience to know that you are building the film level. But with practice like I said I never, ever, never touch the body with sandpaper of other abrasive after I start the FP process.

While we're on the subject of FP...

I was wondering if anyone had an opinion on this stuff:

http://www.shellac.net/RenWax.html

Would there be any benefit to using it? Has anyone tried it?

I am not one for putting a wax coating on instruments and the web site talks a lot about what it will do but nothing about what is in it.

Hi Michael
I did the test. WOW! I don't think contamination comes close to describing it. If it's viral, I think i need to get in touch with the world health organisation!!

So, more guidance needed:

I have some flakes from LMI but could be about 18mths to 2yrs old. Should I try them or just get some new ones?
When I start the re-bodying process is there anything I should do first - considering the last coat would have hardened off somewhat??

Thanks
Mat

It never hurts to try them. Make up a small batch, test and we will go from there. you have learned a valuable lesson about the importance of testing before using.

Once you start to body again do a spirit-off first and wait 10 min then proceed

I got interrupted sorry about that .

The fact we have issues with the shellac that is on the guitar is something we have to deal with not being there it is hard for me to say you need to strip the guitar or not. Lets first try some spirit-off sessions with a new pad, new inner pad loaded with a shellac-cut we know is good. If we are able to level out the pin holes then we will body from that point. If not then we will need to use and bunch of rags and nothing but alcohol and strip the guitar free of the existing shellac and re prep and start over.

I've made up a new batch.
I'll test it tomorrow and hopefully proceed with the spiriting off the day after.
I'll let you know.
Thank you so much for your help Michael. U R A star!!

Here we go Michael
I've made up a new batch of shellac and it seems ok.
I took your advice and have done a number of 'spirit off sessions'.
This has taken the finish back and the pin holes have become more like tears/cuts making them rough to the touch.
I have managed to take a photo, it's not great but you might be able to see what i've been going on about.
The circle to the right shows the little 'pin holes' as they were when I first wrote the post.
The other circles show how the holes have become like tears/cuts.
Should I continue with more 'spiriting off' sessions or should I take it right back with the alcohol??
Thanks,
Mat.

Lets try a tad more spiriting off firat. But I have to say the one the right is what I expected to see the ons on the left I do't quit understand.

Is this happening only on thee top?

It's happening on the sides as well Michael. They tend to bunch up more on the sides. The back seems to be ok (I think)

Actually I’m glad to hear that. If it was the top only the issue would more than likely be surface contamination. But I am very sure it was the shellac. Let me know how it goes.

If you can’t get rid of all the dimples by spiriting off then strip it off with alcohol and rags. You can use clean oil free shop cloths to remove most of it and lint free cloths for the rest. Don’t just throw them away in the trash. Hang them outside somewhere to gas off before you throw them away.