Unusual SG-250 damage pattern

[Commonzense]

Dear all,

The father of a friend of mine runs a fish shop. He owns a T8 to keep his knives sharp on a level required to his profession. They actually sparked me both to get my own T8 for sharpening the tools I use for my profession as a carpenter. In the end somehow I happen to sharpen mostly 'tools' of friends and family. Not a problem, they are welcome and off-topic.

The stone he sharpens on is SG-250. Somehow, but above all mysteriously, something has happened to his stone. In a span of week it was totally disgraced/ demolished as can been seen on the attached photos. I had to take off about 3-4mm to get it back in shape again, returning it back to him as a SG-241.

Has anyone any idea what might have caused this unwheeling, or has anyone ever seen this sort of deformity that can explain to us what might have happened to it. Not to blame or finger point, just to learn. I really cant get my head wrapped round it, it's kinda driving me crazy.

Rgds,
Bas

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[Ken S]

Bas,

I would suggest that you send your photos in an email to Tormek support.
(support@tormek.se).

Ken

[cbwx34]

Dear all,

The father of a friend of mine runs a fish shop. He owns a T8 to keep his knives sharp on a level required to his profession. They actually sparked me both to get my own T8 for sharpening the tools I use for my profession as a carpenter. In the end somehow I happen to sharpen mostly 'tools' of friends and family. Not a problem, they are welcome and off-topic.

The stone he sharpens on is SG-250. Somehow, but above all mysteriously, something has happened to his stone. In a span of week it was totally disgraced/ demolished as can been seen on the attached photos. I had to take off about 3-4mm to get it back in shape again, returning it back to him as a SG-241.

Has anyone any idea what might have caused this unwheeling, or has anyone ever seen this sort of deformity that can explain to us what might have happened to it. Not to blame or finger point, just to learn. I really cant get my head wrapped round it, it's kinda driving me crazy.

Rgds,
Bas

Does he sharpen scissors?  There was a similar looking wheel in a Facebook post that looked like that after sharpening some scissors.

[RickKrung]

Haven't seen or heard of anything like that.  Transverse waves, yes, from the truing tool, but not lateral and so far apart.  Very curious.  Some sort of harmonic associated with the jig/blade/how it is held during sharpening?  Some photos of how you are set up and using it might help.  Are the dark marks at the bottom of the undulation valleys?

I agree with Ken, send an email with photos to Tormek support. 

Likely the only direct cure for the wheel is truing it to remove the undulations. 

Rick

[Commonzense]

Thanks everyone for answering. I'll sent the photo's to support@tormek.se.

There is some staff working in the shop. But no one seems to know anything about this...
And with regard to scissor sharpening, I don't think they have the jig. Will get into this though.

Will update in case Tormek has a clarification.

[John Hancock Sr]

There could be a couple of things. If you are using consistently too much pressure then you can dig into the stone and any inconsistency can be exacerbated over time and cause undulation on the stone. Another possibility is that an inexperienced user may falter and cause the implement being sharpened to jump this causing an unevenness in the stone. Once you get a slight dip this will be amplified over time. One way to prevent this is to use the stone grader regularly. But Tormek help is your best bet.

[RickKrung]

...snip...I'll sent the photo's to support@tormek.se.
...snip...

I think photos of the setup you are using that results in this condition should be posted here and included in what you send to Tormek.  There could be important information in that that is not evident in just photos of the stone.

I agree with John, also. 

Rick

[Commonzense]

@JohnHancock and @RickKrung thanks to you both for your contribution.
The inexperienced-user factor might have played a role here. As the rusty spots made me wonder if (enough) water was used during the sharpening process. Swarf normally is separated from stone and water by the magnet attached to the water reservoir. With regard to the set-up, it is a standard T8. With the standard jigs.

I have been in touch with Tormek. The helpful guy I was in touch with, and his colleagues that got the images forwarded, haven't ever seen this type of stone deformity.. ever. Period.

So I guess this will remain a mystery.
Thanks everyone for thinking along. And big thanks to the TT50.