Hand rubbed question

[J. Doyle]

I have a 1095 blade that is clay hardened. I want to hand rub the finish to show the temper line (hamon).

On one side, I started hand sanding at 220 grit and took it to 800.

I'm starting the other side and wondered if you guys use belts or buffing wheels to shorten the work.

I guess I'm wondering if I'll get the same results if I start hand sanding at 600 grit versus 220.

I don't mind hand sanding and I'm not just looking for a short cut but if I can knock some time off early on, I will.

How do you guys do it?

John

 

[jamiemackie]

I start at 400 or 240 depending on what belts I have at the time. If I have 400 grits belts then ill start at 400, any less then ill just start at 240. You can just start at 400 but youl use a lot of paper and it will most likely take longer.

What I do is do both sides at one grit before moving up so theres no contamination with particles. Also whe you change grit wash the blade and your work area so theres not little bits of 240 when your at 400. Also i work at different angles for each grit, so ill go diagonal for 240, straight for 400, diagonal for 600 straight for 800. On the last grit only work in one direction not back and forth. For lube I use baby oil as it works better than water I feel (with hand sanding knives so no hand rubbing jokes!)

Its a horrible job and one I have to do tomorow.

Jamie

 

[galadduin]

There is a rule applies for me, for the most consistent results obtained by starting hand sanding at the half of the belt grinder grit. For example, if I finish at 400 X on belt I start from 220 hand sanding. 220 on belt, start at 120 hand sand, 800 on belt -> 400 hand sand etc... If you worry about non-flat surfaces you need to hand sand no matter what, even most careful finishes at belt grinder, you'll notice some ripples, mounds or holes on the surfaces. In order to sand them flat you better sand them rougher than the finish... On the other hand some people don't care about surface flatness, they grind to very high grit on belt and hand sand with a soft backing just to remove scratches. I tried this but I found it disturbing as soft backing like leather or cloth lets the sanding grits to scratch the low and high areas at the same time, hard backing will only remove high spots; resulting more time spent but close to perfect surface... I guess a disc grinder would come handy, my next investment to my shop will be that...

Emre

 

[robloveday]

I agree with Emre and Jamie. I always start at 220 grit paper backed by a stone or some other flat, hard material. This is the most important step because a hamon won't look right if there are waves or low spots in the blade (and there always are). After 220 grit things move much more quickly, but like Emre said, always alternate the direction you sand with alternating grits to be sure all the previous scratches are out.

As far as using a buffer, I've never tired it on a hamon knife, but I've been told that it's a very bad thing to do because the goal of hand sanding is to open the "pours" of the steel to bring the hamon out, but using a buffer or even dull sand paper smears the steel, and can hide the hamon.

 

[J. Doyle]

Thanks for the replies guys. Much appreciated.

I guess to play it safe, I will just start hand sanding at 220. I'll alternate directions between grits. I made same sanding sticks out of 1" micarta. It's very flat and has less 'give' to it than wood or plastic.