Nathan
I wish I learned this a year ago. Would have saved me at least $100 and 300+ hours.
1. Don't bother with belts over 220.
2. Use all the pressure you can muster while hand sanding.
3. For your final finish use a rubber backed sanding block and only the edge.
The issue with the stuff seems to be pressure not number of passes. Paper gives out with number of passes, tho. So I've stripped the grit off a lot of paper, without having an effect on the steel.
Remember, the more surface in contact between the steel and abrasive the less pressure you achieve.
(Skip this please if you know it - it wasn't obvious to me):
For example, say your sanding block is 1" wide and area you are sanding is 1" wide and you are applying 20lbs of weight while sanding. If you use a 1/2" wide sanding block you now have the equivalent of 40lbs. If 1/4" it's 80lbs. Likewise the wider the area you are sanding the less pressure you achieve.
On S30V I've done bevels upto 2" wide. If the belt on the sander is 2" that makes 4" of surface area. However, if the bevel is only 1/2" wide the surface area is 1" - that's 4 times as much pressure on the steel with the same push from you.
The higher the grit (I've found) the more pressure it requires. I just can't get enough pressure, safely, on the belt sander. Hence, using narrow sanding blocks by hand.
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That gets me to the final sanding. I use a piece of rubber attached to a wood handle. Then I only use the edge of the rubber with 1500 grit. I'm not removing 600 grit scratches at this point - I'm only blending the surface and removing those cloudy areas.
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Sorry, Nathan, just babbling - and hoping to give you some ideas.
Steve
