general reference shipping damage for japanese bath duckboard

Did you know you can order just a duckboard?

In this case, a friend architect ordered one for (I imagine) a very special bathroom. We had a detailed correspondence about using the planks long wise or width wise. We custom built the sleepers to adjust to the existing slope. The grating was divided in two pieces for easy maintenance. The client chose not to chamfer the corners of the planks for a sharper look. We adjusted the size a couple of times.
Every communication was done in a fast and accurate sequence of questions and answers, like in a ping pong game. Perfect.
Well, almost perfect...
The sunoko is now happily installed, I hear, but... we are having 2 practical problems. I am mentioning it here so it can be of reference for other cases.
We strive for perfection but sometimes problems happen all at the same time...
Please bear with us as we will do our best to assist you in any circumstance.

problem 1) One plank was damaged during the transportation with EMS!

solution 1) All the shipments are insured. If you already opened the box and used it for more than a week, there is nothing we can do from our side. You will have to file the claim to the post office, they will produce a damage report. Send it to us. We will file it to the japanese post office and obtain a refund. Meanwhile we will make a new sunoko section and ship it to you. Sorry for the trouble!

solution 2) No kidding! I confirm we use SUS1818 type stainelss nails.
As you can find on internet resources (wikipedia etc.), the only case that stainless steel produces rust is when it gets in touch with another ferroid material. The chrome coating anti-oxidation barrier of stainless steel is neutralized by the electrolitic effect of the two metals touching.

Cause:
a) It is possible that some metal dust from the hammer remained on the nail head
b) or maybe your water is very rich in iron

Solution:
Dip a moist, soft toothbrush in a box of baking soda. Or you can use a mild pickling gel. Rub back and forth gently on the stained area. Rinse abundantly.