Wet Forming a Sheath Around a Knife

Wet forming means wetting vegetable-tanned leather so it softens, then pressing it to the knife's shape and letting it dry. Tandy picks vegetable-tanned leather for the job because it keeps its shape and handles well when damp.¹ Pick the leather first, using the leather page.

Before the water

• Order varies by maker. The Grit book stitches the sheath first and soaks it at the end.² Weaver forms the sheath first, then glues and stitches.³ For the welt, there's a separate guide to fitting the strip.
• Have the knife, tape, plastic wrap, clips and a towel ready.
• Wear gloves if the leather is dyed or treated.¹

Protect the blade

Water can rust a blade, so wrap the knife before the leather touches it.

• Wrap the entire knife in plastic wrap and secure the wrap with tape.²
• The wrap keeps the water off the blade and prevents it from rusting.²
• It also adds bulk, so the knife will come out of the sheath easily after the leather has dried and shrunk.²
• Use plenty of wrap and tape it in neatly.⁴
• Weaver adds a layer of protective packing tape for the blade.³

Wet the leather

Sources give different soak times. They're for different leathers and different sheaths.

• The leather should be pliable but not dripping wet.¹
• Pat it dry in a towel and squeeze out the excess water.⁴
• Damp leather takes impressions and marks easily, so handle it gently.⁵

Shape it

• Put the wrapped knife on the leather and fold the leather over, forming it over the handle as you go.⁴
• Press the leather into the sides of the knife with a knuckle, and press from above with your thumbs.³
• Spend around 5 minutes on the corners and bends.³
• Clamp the leather in place with spring clips.⁴

Dry it

Let the sheath dry around the knife.²

• Weaver's schedule for one sheath: leave it for 15 to 20 minutes, spend another 5 to 10 minutes refining the shape, rest again, then leave it for about 5 to 6 hours to dry completely.³
• One maker checks it every five minutes for the first half hour, to see that the leather is moulding the way they want.⁴
• You can work with the leather again after several hours, depending on heat and humidity, or leave it overnight.⁴
• Let the leather dry completely. Rushing can lose the shape.¹

Drying time varies with the thickness of the leather and the humidity.¹

Check the fit

• Take the wrap off the knife, then try inserting and removing it a few times.²
• Not happy? Rewet the sheath and form it again.²
• Don't oil yet. Leather dressing makes leather water-resistant, so be sure you like the fit first.²

Mistakes that lose the shape

• Dyeing or casing after forming can oversaturate the leather. If it falls out of shape, the form is lost when it dries again.¹
• Trimming a dried sheath means cutting two layers of water-hardened leather. It takes a little more pressure, so go slow and don't cut yourself.⁴

Sewing the seam comes next, on the sewing page. Trimming the dried sheath is on the finishing page.