Hi Serdar, thank you for your hard work and sharing.
I went down to Home Depot (local hardware store) and picked up a pound of sulfamic crystals and went to work based as a starting point using your recommendations of a 10% solution (454 grams SA to 4.5 liters water) with a soak/agitation for 20 minutes and a wash for 20 minutes. The paper was 200gsm (90lb.) Fabriano Artistico traditional.
Artistico was a favorite of mine a few years until it developed problems and I needed to find another paper. I agree with you that it has a very ‘hard size’ that needs to be broken down before it is printable and in the past I pre-treated FA with a 5% solution of oxalic acid for 10 minutes, no post wash. Also as in the past I used the back of the paper for coating, I never cared for the finely spaced parallel lines I see with a loupe on the recto side. Also, the backside just has a slight texture that I preferred.
I coated up two pieces of paper one with 3 drops of tween and one without tween and got back a measured dMax of 1.30 without tween and 1.26 with tween. Also, the paper coated up very even with the Richeson brush. I always use a reference print when I compare papers and my reference print is from ‘old’ Platine and found the Atistico had more contrast and a bit faster than the Platine with the same solution the contrast can be fixed with a slight tweeker curve if needed.
All in all I was very impressed by results, Artistico was un-printable for me before. In addition there are no irritating fumes to deal with (I heard the HCI was being used for awhile) which I would think could be very annoying especially if you are doing a large run.
I look forward to trying this on other paper as well!
Best - Stan