Scratch pattern on a cheated high hollow?

Tod Lowe

Tod Lowe

Well-Known Member
Hey guys.
Im making a skinning knife and I put a high hollow grind on it using my 8 inch contact wheel. I had to cheat the grind up because the wheel isnt big enough to hollow out this much.
All was good until I was finishing the knife . I couldnt get a good scratch pattern. I ended up spending forever on it and then buffing the crap out of it with black compound.
Would a scotchbrite type buffing wheel be good to clean up scratches in this situation?
All tips and suggestions are welcome.
 
burchtree said:
What do you mean when you say you couldn't get a good scratch pattern?
Click to expand...

Im saying the radious of the wheel doesnt fit perfectly in the hollow so the hollow was done in almost two sections per side then blended. You cant make one pass down the hollow and get the scratches to look uniform. Im talking 400 grit scratches .
 
Shankmaker -

I know exactly what you mean by "cheating the grind" and having issues finishing it out. Regarding your question, I'm not sure which direction you wanted your scratch pattern to go. I.E. Lengthwise for a hand finished look, or across the blade for a satin finish, but here's my 2 cents on Scotchbrite.

I use the 2 X 72 Scotchbrite belts a lot. Both the 600 and 1000 grit but mainly the 600. I love these belts and in your case of "cheating the grind" they work wonderfully. They are thick, about 3/16" thick and they "fill the grind" if you know what I mean. If you took the blade to 400 grit and those scratches are what you're trying to cover then this is the ticket. Again, depending on the direction you want them to run. If you have lateral (lengthwise) scratch patterns, then it will cover them but not totally blend them in.

I've never used the wheels myself - I find them a bit on the pricey side and I use only the quick change wheels (the type that wind on and off vs. being held on with hardware) and I've not seen SB's in that format.

Hope this helps. Email me if this is totally confusing. It's early and I've not had enough coffee yet this morning. :D


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Wayne

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Thanks Wayne.

I didnt think about the 3m belts working . I have been wanting to try them and the cork belts anyway so I will order some.cool 1

Those scotch brite wheels for the buffer do seem expensive but I dont see how you would ever wear one out. Im still gathering info on them...prolly get one of those too.
 
Shank -

One last thing about the 3M SB belts...regarding safety. Since they are thick, and since we grind edge up, if you're not concentrating 100%, I find that these belts like to grab blades and throw them to the ground more than any other belt. And, it's easy to take chunks out of the edge of the belts. Regular belts will tear and fly off if they catch a sharp edge but these guys just keep chugging along even after you're removed a piece. I find that even missing an eraser sized piece along the edge doesn't affect them. I've also had them grab the tip of the knife in the middle of the belt and put a 4" slice in it but again, I can still use it. Just a word to the wise my friend.


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Best regards,
Wayne

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www.jarrettknives.com

Be sure to check out the new Jarrett Knives Forum
 
What you are doing is common. Your problem is common too. It just takes practice. I grind on a 5" wheel a lot and stretch my grinds too. Typically as you go to higher grits you can start to blend things in better and better. I typically can't get a good blend until I approach 45 microns. So you may want to try going to a higher grit. What you doing requires a soft touch and practice. If you have 220 grit scratchs though, you can't get that out with a buffer or scotchbrite belt. You might hide them a little better with the scotchbrite belt but they are still there. You have to go back and get everything even the got to the next belt. I think alot of folks that are just start out don't go high enough before the hitting the buffer. When you buffer something, it should only take a minute or two if you prepped it properly. Remember to use belts like they are free to get good grinds, a dull belts is the worst thing you can use. I dull 220 belt does not equal a 400 grit belt. Hope that helps. Hang in there.
-John
 
John Barker said:
What you are doing is common. Your problem is common too. It just takes practice. I grind on a 5" wheel a lot and stretch my grinds too. Typically as you go to higher grits you can start to blend things in better and better. I typically can't get a good blend until I approach 45 microns. So you may want to try going to a higher grit. What you doing requires a soft touch and practice. If you have 220 grit scratchs though, you can't get that out with a buffer or scotchbrite belt. You might hide them a little better with the scotchbrite belt but they are still there. You have to go back and get everything even the got to the next belt. I think alot of folks that are just start out don't go high enough before the hitting the buffer. When you buffer something, it should only take a minute or two if you prepped it properly. Remember to use belts like they are free to get good grinds, a dull belts is the worst thing you can use. I dull 220 belt does not equal a 400 grit belt. Hope that helps. Hang in there.
-John
Click to expand...

Hey John.
I actually remember reading from your site that you used a 5 inch wheel so I was curious if you would have any thoughts on my issue. Why do you use the 5 inch wheel anyway? Your work is amazing im so not
questioning that.cool 1 Just curious....you must see some advantage to using it.

I generally will milk belts 120 and lower but I replace pretty often after that.
I will give the try to take it up in the finer grits and see how it looks.
Thanks for the tips.
 
Shank
I use an 8" wheel most of the time. I took me a while to really get the feel for blending that line. The way I do is to just slightly roll the blade against the wheel, not alot of roll just enough where I can barely tell it is moving. Ive gotten so used to it I dont even think about it anymore. Just have to build up the muscle memory.

Sean
 
I use an 8" wheel and when I get into the higher grinds ( 7/8 ths and higher) I have to blend as well.

After taking the bevel to 240 grit, I use the maroon SB belt (medium) and then the blue SB belt (fine). Nice consistant satin finish throughout.

BC
 
One last thing about the 3M SB belts...regarding safety. Since they are thick, and since we grind edge up, if you're not concentrating 100%, I find that these belts like to grab blades and throw them to the ground more than any other belt.
Click to expand...

I grind edge down on the sb belts and edge up on everything else, due to their buffer like tendencies.
 
Shankmaker said:
Hey John.
I actually remember reading from your site that you used a 5 inch wheel so I was curious if you would have any thoughts on my issue. Why do you use the 5 inch wheel anyway? Your work is amazing im so not
questioning that.cool 1 Just curious....you must see some advantage to using it.
Click to expand...

Give me a call, it's just too much to type.:D
-John
 
Also; if you don't have a scotchbrite wheel, buy one. They are priceless for cleaning up sharp edges. :)
 
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