I'll pop this in here as it pertains to the discussion above about Dalit Sandalwood soap, which is a lovely soap with a really true sandalwood scent ... but it's not a great shaving soap. It's also a little "dark" (read: dank) due to, I think, the neem oil. That does dissipate somewhat once the soap has been let out to breathe.
Lathering up, as is, produces a thin but stable enough lather ... although when I used it, I did have to re-lather mid-pass.
I mused that it would be dramatically improved by something neutral, but known to produce volumes of slick cream. The scent is quite powerful so it would take some bashing, but I didn't want to alter that unrefined essence. I have some Vitos (Green) in the loft which has long lost its scent but in case it did have any residual or pulled a Lazarus on me, I thought that an expired woody almond scent would not be a bad thing mingling in with this soap.
Formulation?
The Dalit soap weighed 95g, so chopped in half was 45g (ish). I went with 30g of Vitos (Green) initially, which would give me some wiggle room if it still wasn't a good blend.
... and here, I hit my first problem. The Dalit soap was very dry and kinda crumbled/shattered when cut. I was not able to grate it on my usual large grater that does a sterling job with more moisturised soaps and sticks. I had to pull out the parmesan grater and that took some time. The Vitos, too, was dry and kinda crumbled apart, so the parmesan grater did a sound job.
... and here, I hit my second problem. The resulting soap was a fine powder and was in no way going to behave putting it back into a container. I had to make up a thick paste with hot water to get the soap back into a pliable consistency for putting back into the bowl. Using just too little water was about right as the resulting mess was indeed a thick paste. Spooned back into the bowl and pressed/moulded with the back of the spoon, and we're back in business!!!
Test lather ...
Which produced something I am very pleased with. The deep, raw sandalwood scent is still very present, dank still. But the lather is dramatically improved! Thick and luxurious with a nice sheen. Very much a lather I'll be happy to shave with.
So, ratio: three parts Dalit to two parts dried out Italian croap < Vitos, TFS or 3P would all be fine