Need advise/tips on primary grinds for this knife

REK Knives

REK Knives

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Knifemaker / Craftsman / Service Provider
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I wanted to post here to see what you guys think and get advise. Here is the knife in question, this is just a prototype rough blank.

knife%2520blanks.JPG

I will receive it as CRA 1095 carbon steel, so it should be very easy to grind. The blade will be 3/32" thick and the blade itself (not including the handle) is 6.5". The narrowest point (from spine to edge) on the larger knife (which is the one I'm focusing on right now) will be 1/2" thick. I am thinking about putting a mid-grind on it using a jig similar to the picture below, which is apparently pretty common for knife makers from what I have read.

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I have a 2x72" settup that I can customize the tool arms on. If I do a mid grind then I would try to keep that grind paralell to the edge (obviously). How hard will the recurve be and do you have any suggestions? Thanks for any advise or tips!
 
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no joke! that's why i need advise from the experts here =)
 
I'm curious. What's the purpose of that particular blade shape/style?

Syn
 
That was a poor way to say, perhaps you should try something easier first if you have not yet done that. Getting a belt grinder, even the best there is out there does not give you a tool that will allow you to do even a reasonable job to begin with. Give yourself a break and get some mild steel to practice on. Perhaps 20' - 30' will give you an idea what you will have to do. Locking it in that "sled" and trying to do what you are wanting won't do it. Practice and repetion may. Frank
 
What Frank said is true,better tools does not make a better craftsman.It may give you a better chance at becoming a good craftsman. But you still have to put in the time and learn.I am telling it like it is.I know what to do ,but getting my hands to produce the job I want does't happen everytime.It could be Murphey's Law.
Eddie
 
its a fillet knife... you are probably right, but i'm going to try to make it work =) i will get some scrap mild steel in that shape to practice with first.
 
I have made hundreds ( maybe even a thousand) fillet knives....and none of them resembled that shape. Look at some photos of fillet knives and see how the blades only need to be two things.....long, and thin. Any whistles and bells aren't useful in a fillet blade. If you took that reverse belly out of them ( make the blade straight), they would be good fillet blades.

3/32 ( .090") is OK if you want a stiffer fillet blade, but be sure to put a full distal taper in the blade. I use 1/16" (.060") for most of mine the size of yours.
1095 will work well, but be sure the HT is spot on. I prefer CPM-S35VN for fillet blades.
 
Please followup on this and let us see your end results ( or even interim progress ).

Just my 2 cents but there's a lot of experience in some of the posts above. Sometimes the tried and true patterns that have proven themselves for centuries are just that - the right answer.

Good luck

Syn
 
Thanks for the advise... I am sure that the experience given is accurate, but I will give it a shot anyway. And I will try to keep ya'll posted =)
 
Got them in and got the first one done! Went much better than I expected... unfortunately, due to the recurve I can't do a full flat grind.

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This is finished to a 180 grit belt pre-heat treatment... I left the edge about .020 thick. The blade will be coated with some type of finish after I am done, do you guys think I can get away w/ leaving it at 180 (I will finish it up post heat treat and thin the edge out before putting the final edge on it).
 
bladsmth said:
I have made hundreds ( maybe even a thousand) fillet knives....and none of them resembled that shape. Look at some photos of fillet knives and see how the blades only need to be two things.....long, and thin. Any whistles and bells aren't useful in a fillet blade. If you took that reverse belly out of them ( make the blade straight), they would be good fillet blades.

3/32 ( .090") is OK if you want a stiffer fillet blade, but be sure to put a full distal taper in the blade. I use 1/16" (.060") for most of mine the size of yours.
1095 will work well, but be sure the HT is spot on. I prefer CPM-S35VN for fillet blades.
Click to expand...

Why do you prefer CPM-S35VN and what do you mean by full distal taper (please excuse my ignorance)... would it be something like this photo (below)?

IMG_0545.JPG
 
Yes, that is full distal taper - tapering from ricasso to tip.

In like S35VN for its hardness - Rc 60-61; Its availability in many thicknesses and sizes; for the fine edge it takes, and for how well it holds that edge.
 
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