How To Regrind by hand (no power tools)

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SharpPancake

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Dec 30, 2018
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Is it doable? What technique is the best for it? What stones are good for it?

I was just thinking about reprofiling some full flat knives, convexing last few mm behind the secondary bevel and thus thinning it.
I guess I need some really coarse stone for it, something like DMT XC (or maybe something else, even XXC).
Any tips on the actual proces, or just lay the knife almost flat of the stone and work on it for a few hours?
 
Coarse waterstones work for me. I put a convex edge on a Ratmandu, Rodent Solution, and a few others, just using waterstones. Works great, but time intensive. I started with a 400 grit Chosera. That sucked. Took me a few weekends of drinking beer and grinding for 20 mins at a time to get where I wanted.

I got a 150 grit Nubatama and that helped out a lot.

Now I have gotten proficient enough with my belt sander that I would probably do a convex reprofile on it, bc I can usually reprofile to shaving hairs in 30-45 mins.
 
Belt sander works great for this. I modified an angle guide for my harbor freight 1x30 for 5 degrees. I do that til i reach the edge. I start on 24 to 40 grit to 80 to 150 to 220. Dip every swipe on the wheel. Then put your cutting bevel on. The low grits save lots of.time. but you have to see how much your thinning. You may definitely start at a higher grit. I wouldn't do this by hand. I don't have that kind of time on my hands. But that's every man's choice. I didn't buy the belt grinder for knives btw. Had it for several years prior.
 
Get cheap belt sander,i put most knives on belt sander first,then use couple stones,and for quick maintenance few strokes on sharpmaker.Nothing can beat edge off the stone!
 
Paper wheel can deliver a wicked edge fast. Is it better than a stone? No but it's in there. Close enough. And in no time flat. I did a few rat 2s. One by hand one with the wheel. Both push cut the same. Both shave arm hair the same. Freehand took me 15 minutes thru a 15k suehiro. The paper wheel took me 2 minutes. The hand edge was a little prettier. But I can't see a difference in practical use anyway.
 
SharpPancake said:
Is it doable? What technique is the best for it? What stones are good for it?

I was just thinking about reprofiling some full flat knives, convexing last few mm behind the secondary bevel and thus thinning it.
I guess I need some really coarse stone for it, something like DMT XC (or maybe something else, even XXC).
Any tips on the actual proces, or just lay the knife almost flat of the stone and work on it for a few hours?
Click to expand...
I've posted this LINK>>>> to these photos a lot lately (regular readers be warned) but maybe it will be of interest if you want to work without power tools to shape the blade.
See the very coarse diamond file; part of the attraction is that it is longer than a stone and you can put more downward force on it than rubbing the blade on a stone.

DON'T BE AFRAID OF PUTTING SOME FAIRLY HEAVY PRESSURE ON THIS FILE.
The place where people get into trouble putting too much force on a diamond stone is when they are pushing THE EDGE against the diamond grit which can strip some of the grit off the stone.

Just pushing the side of the knife down hard on the diamond will be fine; I have done this sort of thing very often. ;) :thumbsup: :cool:

Page down a bit and you will see I then take out the scratches from the diamond file using a 120 Shapton Pro stone.

PS : I took a whole bunch of thickness off this blade before using the diamond file to blend in the grind marks and do the final shaping. I used a white grinding wheel. For info about that look higher up on that thread. There is a Norton Blue stone that works even better than the white wheel I was using back then. I now have the Norton Blue stone to do the same work; it cuts cooler and faster.

It is without a doubt better to use the sanding belts rather than the round stone.
I'm not a knife maker and do not plan to get the high quality belt sander and that is why I opted for the round blue stone. I just fool around doing a few knives for my own use.
 
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The more surface area in contact with a diamond plate, the harder you can push without damaging it. Remember the pressure you apply is divided over the area that you apply it in - for instance pounds per square inch... high psi will damage a diamond plate by dislodging the diamonds, but what the cutoff/threshold is I'm not sure. I'm with Bill on the belt sander for heavy stock removal though.
 
Can't post pic. It's asking for a URL. Look up angle guide for 1x30 belt sander. If you look at it sideways it has a track..comes stock 10 to 45 degrees. There's plenty of room on the low end. Drill a hole the same size as the track . Drill several and then remove the rest with a small file to allow it to ride the track. Use a protractor. Easy peesy. About 15 minutes work. Pm me your email or phone number and i can text or email a shot of mine sometime tomorrow.
 
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Before I bought the 2x72 grinder, I used 80 grit rynowet sand paper and a lot of elbow grease to finish the full flat grind after it was heat treated. It’s not fun, but certainly doable. Usually i would take the edge width from 0.030” down to zero, and then convex up towards the spine.
 
Yes, it's silicon carbide paper, and i think WD40 oil works more efficient than soapy water.
The grit seems to cut better for longer and the swarf also stays in suspension noticeably longer.
When the paper eventually loads too much you can refresh it a few times by adding some more WD40.
The oil also prohibits flash rust when working on carbon steel types.
 
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