First knife design/plan

The decrab has an orange peel look when I sand it, and it is 0.003" thick or so. It can be more if you overheat/oversoak.
 
Just to be clear about my post toward Larry, I was not a trying to be a jerk or anything, and I see that he was being serious. I agree that the advise he gave was good, it just seemed out of place at 3am and didn't quite think my post through, which is when I read that and commented. I apologize if I was being a little snobby with that.

About the etching; do you mean just soaking the blade in vinegar, or doing something special with it? I honestly have zero experience etching anything, and don't even know where to start researching that. I have a thread bookmarked on how to force a patina with vinegar, but no etching. Could you point me to a thread explaining what to do, or give me a quick rundown of what needs to be done? I have already sanded off the scale on this knife, but I can quickly HT a scrap piece to etch.
 
Not much to it. Just take this blade to your desired finish and clean it up by scrubbing with dish detergent and hot water. Rinse well and, before it dries, dunk blade into an appropriate volume of fresh white (household) vinegar. Let it set for a few minutes then remove and rinse under hot tap water.

When you take it out of the vinegar it will be covered with a thin layer of black oxides that need to be removed to reveal the steel surface below. Many ways of doing this but a rub down with detergent on a damp paper towel is effective enough here I expect. (I use a scrub of loose 1500 grit SiC powder mixed with a little toothpaste or detergent on an old, but clean, toothbrush.) Your formerly perfect satin finish will likely show an array of odd stuff the first time you do this. It can emphasize deep scratches that were missed earlier, any surface cracking/crazing (bad news), different phases of same alloy (e.g. martensite vs pearlite), and any decarbed surface steel. Sidenote: vinegar also removes mill and forge scale given enough time/temp.

From there, just step back a grit or two on a hard flat backer to carefully cut through said decarb and again refine your geometry (here's a golden and often underrrated opportunity to "ice the cake" IMHO.) Then bring to a fast but uniform satin again, etch and sand out. Repeat as needed. Experience will inform.

You've got this I do believe.
 
What I'm getting from this is this is to get the finish absolutely perfect (i.e. remove decarb, scratches, etc.)? Seems like it will work pretty well. Once I finish sanding I'll start on this.

Just to be sure, about 10min is good? A lot of people have very different definitions of "a few minutes", so I find it always helps to double check.

I'm trying to get this knife done by hopefully next sunday, which is when I'm going on two 1-week long camping trips back to back, so expect to see this thread updated a lot in the next week.
 
Oh man - you should've said you were taking this one to the boonies for two weeks. I would change my tune and suggest you forget the quality finish here and concentrate on the edge geometry and basic ergos. Look up the generic cold blue and bleach finishing and go beat the snot out of this one. Performance is everything and ugly knives generally seem to know how to have more fun.:thumbup:

Time in vinegar. Doesn't matter really but short etch cycles with mild acids appear better at the discovery thing because they are maybe slower and therefore more selective relative to stronger acids tending to chew everything on contact. Pitting isn't generally a problem with vinegar. Overnight soaking is fine until near final finish on carbon steels.

If your HT was swell, you may be be surprised at how thin you can take your edge and still have a tough efficient cutter. This is where hand-made knives can really earn their keep IMO. Sounds like time spent on edge geometry and handlle ergonomics will pay off way better than a nice satin finish on this knife shortly.
 
No no no no no. I am definitely doing this one right the first time. That satin finish should only take a day or so to do, if I work on it for several hours. The first trip is just a camp (not quite camp-ING), and while the second week is more survival oriented, I will also have my leatherman wave with me. I'm making this knife for the sake of using it, AND to impress people LOL. I can make a knife just to be used later, but this one I'm trying to make to be used and to impress.

I am going on a quick weekend trip starting in the morning until Sunday afternoon, but after that I have the whole week to dedicate to making this knife.

Wait, so am I soaking the knife for 10min or overnight? I'm getting some mixed messages here about how much time it should me in. How much time would you leave it in if you were doing this?

On a side note, I also finished lightening up)/making a reservoir for the epoxy in the tang. I just drilled a bunch of 1/2" holes and dremeled down ~1/32" into the tang 1/8" from the edge. When I get back on Sunday I'll find something flat to put sandpaper on and flatten the tang and handle scales. I'll do this in between sanding the blade.
 
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Ha... I understand now I think! Every single knife you build should be to impress people, starting with you. How that is done is the question. I'm just saying that comfortably cutting circles around cheap factory knives is one way.

On the etch time again; maybe try 2 min x 3X soaks while scrubbing oxides in between. Not too important though. Just remember the goal is a uniform gray etch across every blade surface you have ground/shaped. Even though it's hard to differentiate decarbed steel that's freshly sanded, if you don't clear it now, your user-type carbon steel surfaces will inevitably patinate and likely show that pattern revealed now by the vinegar (plus a bunch of other weird stains with some good stories behind them!)

But don't over think this though. Concentrate on both your edge and handle geometries first. Time wasted on finish work applied to poorly shaped knife parts does not impress anybody but maybe your mother...:)
 
Alright, so I've just about finished sanding the blade, minus the vinegar cycle. At this point, I don't think I'll be bringing this knife to camp, because even if I somehow manage to finish it, I'd still have to make the sheath. And that's after the epoxy dries, and I can put a few coats of tru-oil on the handle.

I'm not too upset because the first camp I'm going to is a boyscout camp, which has a blade length limit of 3 inches for minors. I'll have my leatherman wave with me for both trips anyway, so whatever. This will be done for future trips, and all this means is I can go slower and make sure I'm doing everything right instead of rushing.
 
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