jpm2 wrote: ↑
Sun Oct 27, 2019 6:08 pm
Yes, the sage1 is a Taichung model.
I'm relieved to hear someone else has had this experience, tho sorry about the aggravation it causes.
It's hard to tell how far you've taken your edge back from the pictures, but I feel confident if you keep going, it'll get better. There's only one way to know for sure...
At first I was grinding at a higher angle than normal on coarse silicon carbide. AS I started seeing/hearing/feeling improvements [after many sessions], I gradually lowered it back to where I normally hold, then finish with diamond as usual.
I'm with you on possible heat treat issue, but leaning more towards too thin at the edge pre heat treat.
Makes me wonder how many of the reports about s30v being chippy and prematurely losing it's fine edge might be related.
I doubt there's very many people persistent enough to keep grinding their edge away, just for the sake of experimenting.
Sorry that you’ve had those issues too, but it’s also a relief to me that someone else has experienced the same problems.
It’s interesting that you had the issues in a Taichung knife and mine are in a Golden model.
I hadn’t considered the issue of the edges potentially being ground too thin behind the edge before heat treatment, but that’s certainly a possibility, especially when combined with those knives in each batch which come in at the top of the target hardness range.
Ok, sorry for my delayed reply, but I wanted to be able to report some progress, and hopefully the microchipping issue may be slowly stabilising with repeated resharpenings.
In the two weeks since last posting on this, I’ve basically been using this S30V PM2 exclusively.
I’ve deliberately been cutting cardboard recycling down to fairly small pieces, as well as using the knife for gardening tasks like trimming and pointing bamboo stakes and cutting down plastic pots, as well as basic prep in the kitchen like rough slicing leftover vegetable odds and ends to make stocks. I haven’t been abusive with it, but I have pushed it so any issues would become apparent.
At the end of each day I examined the edge with a 10x loupe, looking for those tiny half-moon chips barely visible to the naked eye.
At first I sharpened the knife very lightly as previously described, with the flats of my worn in Spyderco 400 mesh diamond rods.
At the end of the first day, about 4 or 5 tiny chips appeared.
Next day I resharpened again, removing the chips, and after a day or two of use the same chips appeared.
Sorry, this blurry pic is about the best I was able to do while holding the loupe and phone camera and trying to get the focus and lighting right:
Next resharpening, I decided to use the light ‘up and down scrubbing’ motion on the rods to strip away steel. Once the chips were removed, I used the light finishing pass progression of 10 on one side before switching to the other side, then 5-5,4-4,3-3,2-2; then 1 per side for about 10 ultra light passes, going from one side to the other to ensure burr minimisation.
I like the coarse edge, but it’s not quite what I’m used to in most of my knives.
This time I decided to do a few light passes on the brown rods to clean up the apex a bit.
Interestingly, every time I used the ceramic rods, no matter how lightly, they knocked out microchips all along the edge, which were only visible with the loupe.
I’m currently using the 15dps setting. Of course, the 20dps setting will provide more durability, but S30V should be able to take a 30 inclusive edge without issues.
Next sharpening, after ‘scrubbing’ with the diamond rods then deburring as described above, I decided to try a coarse 60/40 μm Venev diamond stropping paste on balsa.
This grit size would be around 220-400 grit.
I did a couple of light passes then stropped any residual paste off the blade on clean balsa, and clean roo leather.
This actually worked really well, leaving the edge still very aggressive, but slicing through paper much cleaner and smoother.
At the moment I’ve probably sharpened away at least a millimetre or two all along the edge, and done at least 5 or 6 full resharpenings in the last couple of weeks.
The microchipping seems to be clearing up a bit, but the odd chip here and there is still evident, following a day or two of use.
Given the effectiveness of the 60/40 μm strop, I also pasted up a Venev 10/7 μm diamond balsa strop.
That progression actually produces a really nice edge - 400 grit diamond rods, then a couple of 60 μm passes, followed by a couple of 10μm passes, then a couple of cleaning passes on roo leather.
Anyway, I hope that I’ll be able to report that my issues with S30V in this knife have cleared up with quite a bit of repeated sharpening soon. I’ll start running this knife in parallel with one of my other S30V blades, once it stabilises, as a comparison.
Thanks for the advice guys. This knife has been quite frustrating, but learning how to resolve troublesome issues is a valuable experience. Also the coarse stropping has been a useful ‘discovery’.
Jpm2, I daresay you’re right - most users wouldn’t bother to go through that many sharpenings to try to see if the edge stabilises. I’ve also sharpened this knife on lots of different media (CrOx, SiC, AlOx), and with different techniques before this as well.