Thank you very much Hamish, without your advice I'll never start this adventure
Thanks also to all other forum fellows for your appreciation.
The knife is a gift from a friend who is a knifemaker so I'm quite happy to complete the job with a good sheath.
There are some issues regarding the sheath. the first was due to the tape layers around the knife during the wet moulding. They enlarged the total volume of the knife so, once removed, the blade doesn't thightly fit into the sheath. the second issue is regarding the cardboard used to protect the clamps. it was ondulated so some stripes appear on the leather surface. the third is the direct use of the clamps: with a wooden liner probably the compression would be more omogeneous