AS I am about to star on the first layer of planking which happens to be Walnut 1.5 mm x 6 mm , which is not the easiest to bend, however I am managing . The problem seems to be securing the planks. As there will be a second row of planking I thought I would like to try pinning the planks. I have laid a few and after drilling the planks I am finding it much easier using 7mm brass nails However I thought it would be a good idea to remove them afterwards however I am finding this almost impossible