I cracked my SG-250

[brianchin10]

I volunteer weekly at the soup kitchen sharpening knives. This past week was cold in Maine (20-30°F) and after an hour of sharpening, I left my T8 in the truck. I'm bummed out... I had only reduced the diameter to 246mm, granted I just bought the machine in November.


Can I still sharpen on this as is? The cracked piece is very solid — there's no flex or play on it. I cannot close the gap with hand pressure. I may be about to true it all up... Don't like the idea of it though.


What should I replace it with? Diamond?


Cheers,
BRIAN

[Elden]

Brian,
   I have used a wheel that was cracked across the width of the stone. Other than it causing the stone to wear out quicker, it didn't cause me problems. I didn't use it regularly. When the stone would become uneven at the crack area, the TT-50 was used. I never had any problem with tools tending to catch.

[RickKrung]

Something similar to that happened with my SJ stone.  If fell from a folding table that collapsed.  At the time, it had gotten soaked with acetone and had swollen badly.  The cracks were huge.  I posted about it here.  After the acetone evaporated, the stone returned to size and I trued it.  Been working fine since. 

Cracks in my SJ were lateral, though.  Your crack looks like it could be more problematic, probably mostly when you true it, which you will have to do.  Won't be of much use if you don't, in my opinion. 

I would traverse the crack VERY slowly with the truing tool so there is less shock as crosses the crack and starts into the smaller section.  Of course, I traverse very slowly anyway, but I'd go even slower and would be taking VERY light cuts. 

Rick

[cbwx34]

I volunteer weekly at the soup kitchen sharpening knives. This past week was cold in Maine (20-30°F) and after an hour of sharpening, I left my T8 in the truck. I'm bummed out... I had only reduced the diameter to 246mm, granted I just bought the machine in November.


Can I still sharpen on this as is? The cracked piece is very solid — there's no flex or play on it. I cannot close the gap with hand pressure. I may be about to true it all up... Don't like the idea of it though.


What should I replace it with? Diamond?


Cheers,
BRIAN

I question whether the stone was defective to begin with?

Here is why I wonder...  Tale of a Frozen Tormek

and

Water freezing on a Tormek Wheel

Not sure Tormek support would do anything about it, but might give it a try.


One person glued a broken stone back together... maybe contact him and see what he used, and if it still works?

Glued stone

[brianchin10]

Interesting posts... I'll reach out to Tormek and see what they say.


I was able to true and did some tests on some personal knives. Seems to work OK. I cannot close the crack, but I might see if I can at least fill it with something... Will keep you updated.


Cheers,
BRIAN

[brianchin10]

Update on the cracked wheel:


I opted to intentionally break off the piece, with the hope that I could better epoxy the broken-off piece than try and fill the gap. I did this by forcing the crack closed, and hoping that the break stayed controlled. See pics 1 and 2. I was very surprised how deep the crack went into the center of the wheel (pic 3). I've epoxied the pieces together and will re-true the wheel. I am pleased with this result.


The piece still sits a little proud on the side of the wheel and I haven't yet decided how to flatten it, however I'm thinking of using a granite plate with some wet abrasive paper and slowly abrade until it's all co-planer.


Best,
BRIAN

[John_B]

Great job saving the wheel.

Let us know periodically how it is holding up.