My first knife "order"

The review is in... the bog oak knife (made specifically for left hand use) "slices like a dream". I'll collect the "ambidextrous" knife and refine the edge some more, then give that to someone else (likely my mother).

Next I'll set about making the chef's knife to go with the slicer. I just ordered a 4" x 12" x 0.1" piece of CPM S35VN. Had to order from USAKnifemaker because Aldo is still out of stock.

Anyway, I learned something from this. Lefties (at least this one) actually do prefer blades specifically edged to their cutting style. Good to know.
 
After doing some research over the weekend I decided to pare back the blade on the chef's knife from the first cut width of 2.25 inches down to 1.625 inches. That makes the profile look a lot more like what I expected a chef's knife to be, yet preserves that rocker motion I liked about the original profile.. I also shortened the tang to 4 inches, though the handle will still exceed 5 inches, as before.

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I asked him if he wanted another handle like what he has on the slicer or something different. He wants another bog oak. This time I'll cap it with African Blackwood instead of G10. I may have to make more of the bone spacers too. Need to check my "fiddly bits" box.
 
I'm getting a bit frustrated with the chef's knife project. As you can see, the steel I bought came with mill scale. I've spent at least two hours at the grinder removing the mill scale, and have yet to really even start the process of grinding the bevels. Problem is that getting the mill scale off left me with uneven surfaces, and I've worn out two belts trying to get the blank to a good starting point. I started off with a 36 grit ceramic belt, and then jumped to a 150 grit. The 150 grit got worn down, so I went to a 180 grit (since that was the lowest I had above 50 grit). Now it's worn out. I just placed an order with Trugrit to resupply that range of belts... and I still don't have perfectly flat surfaces yet.

Lesson learned: From now on I'll pay extra and buy the stock with scaled already ground off.

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Greg,

Something has to be really wrong for it to take so much to remove the mill scale with so much effort.

You should be able to put on a 50 grit belt and on your contact wheel remove most the scale with several passes running the blank length wise up and down on the wheel.

Then take it to the flat platen to flaten it out or a 6x48 (if you have one) to flaten it out.

It really only takes a few minutes for each side... sure it is a pain but grinding for 2 hours means the belt is shot

This is 440c and the scale was remove in about 15 minutes going from 50 grit to 120 grit to 220grit to get to this stage

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All the belts I used were new, previously unused belts. They didn't start out as shot, but they sure ended up that way.
 
I'm surprised that a fresh 36 grit ceramic didn't remove the scale instantly. Almost equally surprised that the 150 didn't last.
 
Did you use the bottom of the contact wheel to remove the scale moving the blank along the long axis?

Trying to use the platen is much more work on the belt and on you.

Really it should only take minutes to remove the bulk of the scale on the contact wheel.
 
Are you pushing hard enough to expose fresh grit? Conversely, you're not scraping all of the grit off before you get anywhere are you?

IOW, you should knock the corners down on the edge of the blade before you start grinding your flats so that the 90 degree corner doesn't shear all of your grit off.
 
Part of the problem was that beneath the scale was some significant pitting. All of my efforts to remove the scale and the pitting left me with deeply cut swaths in a field of clean steel. So then I would go at the blade from various angles on the platen to attempt to flatten it, which in turn just created unevenness elsewhere. I was chasing hot spots, which I know better than to do, but was so frustrated by the process that I did it anyway. When I finally calmed down and started doing more normal passes it was clear that I still had some serious gouges to work out, so I decided to call it a night.

Anyway, regarding your question about whether I was exposing fresh grit, I'll admit I'm not smart enough about grinding to know how to do that. And whenever I attempted to use the contact wheel in the descaling process it generated serious gouges, so I eventually abandoned that approach.

I'm certainly not blaming the tool for my problems. It's clearly my ineptitude limiting me here. About all I have going for me is my patience and perseverance. ;)
 
I know this doesn't help much now, but next time order surface-ground steel. Aldo only charges a small fee to grind everything clean, and Chuck often has surface ground stock as well. Call and ask them before ordering. It's definitely worth it for us spark-makers (not so much for the hammer jockeys). You could have spent all that time grinding the bevels and be done by now ;)
 
Definitely. I know that now.

As an aside, Aldo has been out of CPM s35VN for months now. This batch came from USAknifemakers.
 
I haven't bought from them in a quite a while; it wouldn't hurt to call and ask them though.

Anyway keep at it. Kitchen cutlery is fun stuff :)
 
Do you have a large magnet to hold the blade with while you grind? They really help getting things flat on the platen while grind length wise on the platen.
 
Actually, yes, I do have a large magnet. It never occurred to me to use it that way. Doh!
 
Often if I'm facing heavy scale I just take it off with an angle grinder. Zipping around lightly with a hard wheel to color it off doesn't leave low spots if you're careful. After that, starting with the platen and a fresh roughing belt should go like butta and extend your belt life a lot. As a forge guy I deal with scale a lot.
If you grind with a push stick (really helps on wide flats) I recommend making yourself a push stick that supports wider blades more fully. Takes more effort out of it and you don't burn your hands when roughing.
Looks like you're getting hooked on the kitchen cutlery. It happens!
 
AVigil said:
Do you have a large magnet to hold the blade with while you grind? They really help getting things flat on the platen while grind length wise on the platen.
Click to expand...

tryppyr said:
Actually, yes, I do have a large magnet. It never occurred to me to use it that way. Doh!
Click to expand...

Stainless steels typically don't stick to magnets very well.

Some decent quality, double sided carpet tape would probably work a little better, although it has its own inherent limitations as well.
 
knife to a gunfight said:
Stainless steels typically don't stick to magnets very well.

Some decent quality, double sided carpet tape would probably work a little better, although it has its own inherent limitations as well.
Click to expand...

My S35 VN and 440C stick nice and strong to the Knife magnet.
 
I am freaking thrilled now. I dug around in my workbench and found a misplaced brand new 80 grit belt, and I'm here to tell you it worked a wonder on the blade. In less than an hour I went from having a pitted and grooved blade blank to something that is pretty close to having primary bevel grinding done. Simply amazing what the right belt can do.

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Today I spent my time hand sanding with 120 grit cloth trying to get it flat and even. As an aside, the trick of using the strong magnet is not so effective when you have a steel platen, as I tdo. I wish I could say I figured this out before the magnet clamped on the platen and stopped the belt cold... but that would be a lie. So I flattened it the only way I could.

Okay, so let's check the numbers. Originally this steel came to me .103 inches thick and coated with mill scale. After clearing the scale the piece ended up being about 0.07 inch thick. After the 120 grit sanding the edge is sitting at about 0.014 inch thick, so right at the tolerance line, and I still have a fair amount of hand sanding to do. No problem, of course, I can always knock the edge back a bit when I get done sanding the flats.

My bigger concern is that there is still a visible valley on one side of the blade, so I need to keep working the flats until that goes away. By then I'll wager the spine will be 0.06 inch thick. And if you are into numbers, the blade that started out as a blank weighing 4.4 ounces, is now tipping the scale at 2.2 ounces.

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