Old Rapala fish knife question

K

KenHash

Joined
Sep 11, 2014
Messages
4,682
I dug up an old Rapala fish filet knife I had for many decades that I stopped using a long time ago. It is marked J. Marttiini Finland on the blade and has the Rapala fish mark on the handle. Found the same knife online and grabbed a photo. I tried sharpening it and found it rather unresponsive to my stones. Does anyone have an idea what stainless was used for these knives? They still are being made and I found them on the J. Marttiini site but typically no reference to type of steel used. Thanks.
aAB0c2.jpg
 
My experience with these are of some very hard stainless. I always struggled to get a good edge on them.
 
Mine came with a pull through ceramic V doohickey. It's the easiest way I've found to keep a keen edge on such a flexible blade. If I can wear out a filet knife sharpening it, my fly rod is still an heirloom.
 
You're not alone! I have no issue using bench stones to sharpen my stiff Landi fillet knife that uses 440C steel... But when I try to sharpen my flexible fishing fillet knife with softer steel all bets are off. I just can't seem to get it sharp. I've taken to using a diamond Jewelstik from Baryonyx (@FortyTwoBlades) and finish it on a strop. Seems to do well for me.

My brother uses a Sharpmaker on his (a flexible North Arm Kermode in S35VN) with good results, but I find sharpening longer blades on the Sharpmaker to be a bit of a hassle.
 
Last edited:
Thanks all. Reassuring to know that I'm not alone.
Good grief, I can't see how a "soft" steel like 420 can be so difficult to sharpen. I wonder if the blade being flexible (compared to all my other knives) has something to do with it.
I any case, I am going to hit it with my Diamond tomorrow and see how that fares.
 
I have a similar ancient Rapala knife - probably 45 years old or older.
It's just marked Stainless IIRC.
Mine has a very shallow - 15 degrees or less - blade angle & sharpens right up with only a few strokes on the fine side of my India Oil Stone.
 
I use an old, Old Timer Honesteel on my rapala knives. Never had an issue getting an acceptable edge
 
My experience with an old Rapala was similar. It had a convex grind and a blunt edge. Like it was initially ground with a slack belt. It took a while to thin out the ege and put on a grind suitable for sharpening with flat stones.
 
To sharpen a convex edge, I use either a slack belt grinder or sand paper on a mouse pad (edge tailing).
 
I had a 4vinch Rapalla filet knife, back in the 60's and 70's (didn't need more blade for bluegill, crappie, gar and small up to 3 or 4 pound bass, walleye, catfish, etc.)
(Yes. Gar is eatable. Firm flaky white meat similar to big mouth Bass, and zero bones. We used the same (stale) beer batter for them as for the bass, catfish, bluegill and whatever else there was, for that particular fish fry. (carp were always smoked, never fried/baked/broiled/BB-Q'd) Be aware that any left over fried or baked/broiled/BB-Q'd gar put in the fridge will "un-cook" overnight, necessitating you re-cook it. I don't know how or why, gar manages to go from cooked back to raw in the fridge.)

Use a light touch when sharpening. Light enough that you're not bending/flexing the blade. I used medium and hard Arkansas stones, and never had a problem...at least not that I remember...sharpening them.
 
The flex is what is causing the issue.

These respond well to water stones. Keep your finger pressure on the blade as it’s on the stone. The fine slurry cuts smoothly.

I have had good luck using dished out K80 stones that create a sort of convex edge.
 
You must log in or register to reply here.
Back
Top