I'm trying out this method on a 15-91 that had a pretty messed-up clear coat. I've gotten as far as going over it with linseed oil & denatured alcohol, and so far it looks like it's doing it a lot of good -- the clear coat has smoothed out a lot. The first instructions I saw were the ones in this thread which said to let it sit for a day to let it cure. When I checked on it yesterday it was still pretty tacky to the touch. Today it's better but still has some tacky areas.

Am I doing something wrong to cause this, or am I supposed to apply the shellac now even though it still feels tacky? I think I followed the instructions closely but it's the first time I've tried this and might have messed something up. It's inordinately humid here -- could that be keeping it from curing properly? Any advice is much appreciated!

Humidity does affect the cure rate. It could be the oil and alcohol was applied too thickly too. I'm hoping Glenn sees this and gives you the real answer.
Rodney

Hi Daisy,
The surface feels tacky from the linseed oil. At this stage I wipe down the surface with naptha to remove the excess oil. Now don't be alarmed after wiping down with naptha if surface looks very dry and a little milky colored. This is normal. If the surface is smooth to your liking you can start the french polish with shellac and a little linseed oil. Just be careful of the decals. You are not doing anything wrong. Yes after removing the oil from the surface do let the old shellac cure for a day or two to harden back up before french polishing.

Could someone direct me to more on French polishing?

The only naphtha I know comes in bricks. Am I to make some sudsy water with it? I will continue reading through thread so as not to ask too many questions already asked and answered.

You are thinking of Fels Naphtha soap, No that is not what you use. Naphtha comes in a can and you can find it at local hardware or paint stores. It is a liquid. Go back and read the start of this thread for more info.

You can buy it in the grocery store. It is the lighter fluid used in zippo cig lighters. It will come in a small yellow bottle. Or as HelenAnn said go to a hardware store and get a qt of it in a can. Yes do go to the first of this thread and I have a good tutorial on cleaning up the machine heads.

I have been a stocker to this site. Using it to restore my born date May 19,1925 Singer. I am having a problem with trying to remove the stitch length regulator. Does it unscrew all the way out for easier polishing? I can't get it to unscrew at all?

It "can" be removed but the re-assembly is a bugger. If it is stuck you can apply sewing machine oil to try to loosen it, if that does not work a few drops of kerosene on it will help break loose the old crud.

Like Steve said they are a bugger to get back in. I have never said so many bad words and then I had to call in the help of my son. Just loosen it.