Boker Ceramic Rigging Knives
I had to repair two brocken tips and then it was necessary to thin down thew blade particularly where the repair was .
I repaired the blades using a diamond belt then I thinned the blades using Atoma 140 it cuts well on ceramic then I used a DMT Fine plate on the primary bevel ceramics never feel like steel knees but in the end although I could not shave on them the edge required needs to be reasonable toothy to cut line specifically Dyneema .
I do some splicing myself and I would elect to use a good steel blade although it needs sharpening much more often I think in general the edge is better I did squirt a little of Ken Schwaltz's CBN onto the plate when finishing of and although I have an Extra extra fine DMT plate I feel that the Dyneema will unfortunately polish the blade overtime.
The centre knife had a complete tip so it was in reasonable condition it just needed a touch up on the primary the others needed a lot of thinning where I repaired the points .
Very nice work. Have you tried sharpening them on non diamond stones. Always wandered if it was possible.
Nice work Diamond Hones /stones , belts would make fast work of this type of repairs for future reference .
I hate ceramic blades I understand people buying them since that stay sharp for a while but if you can sharpen a good laminated knife it will take a far better edge it can be far toothier and if the rigger can sharpen they are easier to keep sharp . I have a Takeda Higo and there is only a primary grind so a couple of passes over a stone soon livens it up and although it dulls quicker than ceramic when it is sharp it is way sharper than the edge on a ceramic and a ceramic will not take the low angle of a Takeda .
I am charging 16€ a knife for ceramics and even then they are an awful lot of work I have a diamond belt but it is 300 grit which may be to coarse I shall try it on my one ceramic which I keep as a learning knife .
I checked out the price of these ceramic Bokers and they are virtually disposable at 39€ each it is odd how on super yachts values can be distorted a chef will buy a Shun which is very popular with Yacht Chefs not in my mind a great knife and then a rigger seems to think that a knife between 40-60€ is expensive .
You can see the mechanism in these knives is not carbon fibre or stainless so they are rusting . It is possible they are worried about getting any oil contamination on their splices with high tech Dyneema or derivatives that rely on friction as any splice but the loads can be enormous (30-40 tons is not unusual ) so perhaps they do not wish to risk any contamination but frankly I would use these as disposable knives in all honesty the value of the lines alone are a lot once you are talking about 50-70 metres of it (anywhere between 400- 800€ for stuff that is perhaps only 12mm over 14-16mm it is considered custom line so the value goes up even more .
In answer to Lizzardborn the only thing harder than ceramics are diamond stones but you can only thin with course diamond once you get to the edge you really need 1200 grit diamond to remove micro chips .
I have some Trizac belts but I am not aware that they will work on ceramic after all ceramic is essentially glass. Generally I use my belt sander for repairs or thinning rather than refining an edge it is really one designed to use jigs the only Jig I like is for plain chisels since it keeps them square but for big repairs it is good .
Have you guys considered the Boye Cobalt knives - these things are designed for saltwater and tough cordage
Oh - and then there is the Spyderco knives in H1