Stan's observation points out the difference between pattern welded barrels and blades.
There may be twisting for esthetic purposes, but the primary process with blades is repeated hammering and FOLDING. 320 layers starting with 5 layers requires 6 foldings.
The pattern in barrels is determined by how the lopin is 'stacked'

[Linked Image from photos.smugmug.com]

Top, left to right:
1. Rampant Lion
2. Chain
3. Boston, a symmetric large scroll 2 iron Crolle
4. Possibly Bernard

Bottom, left to right:
1. Star or American Flag (Ithaca)
2. A higher grade Damas Crolle, probably 3 or 4 iron
3. Washington
4. Similar to Boston, but possibly used for 2 Iron Oxford which was asymmetric.


Then the rods are TWISTED and helically hammer welded.

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