Wire Edge Prevention

[eddosedge]

Thanks for the report KG. We have a question; your post says "While his own knives last through 4-5 steer carcasses (with steeling), our test knives lasted for 2 carcasses and performed well, though for a shorter period." Did he steel the knives provided by you as well?

Yes.
The knives I gave him are the same as his, only new, and he steeled them as he usually does, using his polished and fine-cut steels after approx. every 10 cuts.
His steeling reflexes are set to a different edge angle though, and with our low angle of 12 dps he must have been oversteeling the apex on our knives, and this might be contributing to them wearing quicker.

Anyway, I know I have to shorten the time the edge contacts the felt wheel rotating at high RPM, and seem to have found a solution by a small modification to the horizontal platform.

We are lucky we met this butcher as he can clearly explain what is wrong and what is good, and we've improved our sharpening working with him.
The very first knives we sharpened for him he discarded in the beginning of a boning session because of the wire edge and started me thinking about it 

So for the next boning our butcher will get 2 identical knives from us: one deburred on a felt wheel run on the half-speed grinder at ~1400 RPM, and the second deburred on the same felt wheel run on Tormek at 90 RPM, not knowing which is what - if the knives show no difference between themselves but dull quicker than his own knives, then it must be due to his steeling.
...

And so today I've sharpened two more identical SWIBO knives for live boning trial - these knives are of the same catalog ID our butcher uses for life.
Both knives are sharpened at 12 dps the same way, with only one difference:

The Knife-1 is deburred on a rock-hard slotted felt wheel run on the half-speed grinder at 1425 RPM


While the Knife-2 is deburred on the same slotted felt wheel run on Tormek at 90 RPM


For this test, I deburred the knives using a knife jig for angle accuracy, to rule out any discrepancies; the honing angle is controlled with our computer software.
Both knives score the same 55 BESS - by what have been discussed in this thread, for mainstream knives this is a strong indicator of a clean apex free of any wire edge.

I've asked our master butcher to compare the knife performance between #1 and #2, and to the similar SWIBO knives he sharpens himself on benchstones - he does not know which knife is what, and can tell them apart only by number of dots on the handle. I will have feedback from the butcher either this Thursday or on Monday.
The outcome will tell us whether deburring on the felt at high RPM degrades the edge retention.

KG, would he be amenable to letting you analyze one of his knives after he sharpens it?

Ed K.