Very light rubbing is enough the honing paste should not be too thick. The stone is used to condition waterstones during use.
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They are used for cleaning and flattening the stones before and during use and for creating a slurry of loose grit which is the source of the stones unique polishing properties.
Nagura stone alternative. Herte is an alternative to an nagura. In traditional japanese craft use the nagura stone is a secondary stone used to help create a slurrypaste medium on the working surface of hard or very hard base main or host stones as they were being used for sharpening edges including but no limited to those of razors and all manner of woodworking and metalworking tools. I use that nagura stone on my norton 8000x stone.
I thought the nagura stone was for keeping the stone flat. 120 240 coarse. It does create a slurry and also works to expose fresh abrasive and flatten the stone to a degree between more thoroughaccurate truning with my diamond stone.
These natural nagura stones are used to create a honing paste on the surface of natural water stones in order to refine the grit structure and improve the stones bite on the edge being sharpened. I only say glas because its really flat but i suppose you could use wood if you were worried about it breaking. Nagura question discussion in.
Since op said alternatives how bout a piece of glas with different grit sand papers. I can get a decent edge if need be free hand nothing to write home about. Aid in uniform sharpening by eliminating suction between the blade and the stone clean the whetstone surface from remaining grits and metal particles and flatten the whetstone surface which becomes convex with use similar to water stones naguras come in several grades of grit.
Nagura stones are very useful accessories for 4000 6000 8000 and 10000 grit finishing waterstones. For natural waterstones their use is to wear away hard particles or contamination in the waterstone and to selectively allow flattening by being rubbed on a high spots on the stone. A nagura stone is a small waterstone the word nagura means correcting in japanese.
If its large enough theres no reason you cant use it as a small pocket 8k stone although the quality will remain. The chosera ones come to mind a 400 grit nagura stone with a 10k stone no thank you sir. Imo a better alternative would be an ep or kme stone matching the finishing grit of the knife.
As i understand it the nagura is simply a hard stone often referred to as chalky that.
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