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Maybe, instead of mold, the white fluff is efflorescence?

That is interesting, we have a water softener here and it's possible that it's related.  I cannot understand why a stone would grow mold and how it would even grow without organic material.

The cutter is likely skipping over the smooth side as I'd expect one side of the cutter is slightly more worn and not digging in.  I had this happen in the past.  The grading stone is not aggressive enough to remove material fast enough to get rid of the deep/coarse surface side but if you used it long enough it would even things out likely.

I called support and left a message with no reply, no idea why.  I'm pretty sure it's mold as it sort of goes away after use then comes back after several days sitting damp.  Not leaving it in the trough either, just staying damp for a good while on it's own.

Hi,

I seem to have some mold growing in and on the wheel, thinking I need to run a solution of hydrogen peroxide through the wheel to kill all of it.  Any idea whether this will harm the wheel?  Seems like a vitrified bond abrasive which should be chemically invincible I'd imagine.

Have you measured the edge angle on it?  From what I've seen from Ontario in the past it would not surprise me were the edge angle on the order of 30 Degrees Per Side.  This is about twice as obtuse as it really needs to be in order to have a relatively durable edge for wood cutting.  I'd bring that down to at least 17 DPS, personally.

Hi Rich.  It would free up both hands to position the blade flat before starting the wheel lowering the risk of error in engaging the face to the wheel.

I might be wrong, but it seems to me like a very bad idea: the still wheel with no water running over it has a much higher friction coefficient than when it's already running. So there is a much higher risk for the blade to catch, messing up the blade and potentially injuring you.

I agree completely, seems like an unnecessary risk.

Can you try rotating the diamond cutter so a different part of it is exposed and doing the cutting?

For the shaft, can you use a micrometer and check the runout where the bushings contact it?

I would do both but I do not have a micrometer or even understand what you mean to check runout.  Another thought was that the washer which is just behind the large plastic hand tightened nut that snugs the honing wheel may have been loose.  I will tighten this and see if it matters.

I would try turning the diamond tip but do not have a metric wrench set and it doesn't fit any SAE allen wrenchs that I have so I assume metric.  The recommendation to replace the tip sounds strange because I can see plenty of visible diamonds and they are cutting.  The problem is the inconsistency of depth of cut.

I have run into an issue with this that is constant and cannot seem to overcome it.  I have a newer T8 machine that I have used somewhat heavily, I've gone through almost half the life of the SG-250 stone.  I have trued often with the TT-50 but now I cannot get a flat surface and have also ran into issues of the surface being cupped horizontally AND the surface on the outer side of the stone begins to chatter and cut chatter marks into the stone that look similar to an all terrain tire tread but they are very shallow.  I've tried coming from both sides of the wheel with the TT-50. 

A call to Customer Support lead me to believe I need a new TT-50 exchange tip but I don't believe this is what is causing it.  I noticed the tip has a slight tilt where it is not sitting perfectly level on the stone surface because I've always trued from the outside to inside of wheel.  The CS person told me that I should always go both ways and that this likely caused the tip to go out of flat.  I don't see why this would matter.  I also suspect I may have a problem with the nylon bearing/bushings as I went far longer than I should have without cleaning and regreasing the main shaft.

Anybody care to weigh in before I go play whack a mole with changing components and hoping it helps?

The SVM jig is much better if you want to pivot a knife with a big belly, assuming you have some kind of after market pivot add-on.  This could be addressed in an updated KJ-45 with an adjustable stop, which I would really love to see.

What is this pivot you speak of? 

I generally get around having to pivot blades just by clamping the jig further towards the handle or right at the handle and also angling the jig to match the curvature.  This way I generally get nice even bevel width just about all the way to tip in almost all cases.  Some really heavy bellies on short 4" under blades can be a real challenge though to get it clamped the ideal way.

I do professional sharpening and having both is a must, there's been plenty of knives coming my way that don't fit within the constraints of the KJ-45.  Chopping knives are thick and when they are full flat grind it is not compatible, which IMO is one of the biggest reasons to own a grinder like this in a home environment is reworking heavy/thick tools that would be a major work on stones.

I have been trying to sharpen a friend's Kershaw 1830 with 8Cr13MoV steel.
I have sharpening for several years with pretty good success (sub100 BESS as a consistent goal).
This knife is making me crazy.
I have set a 15deg bevel(30deg included) on a T8 with a CBN80.
I have been trying to raise a burr with a CBN160 wet,edge leading, and cannot.
I have reverted to the SG 250 (coarse) - to no avail.
Any advise would be a appreciated

Advice : DO NOT ever set out with the goal being raising a burr.  I know this is common dogma in sharpening, first raise a burr then remove.  I get it, I try to avoid forming a burr.  Get the apex thin to where it's slicing newsprint and then switch to the finishing stone or leather wheel and make a few light passes.  Drink a beer and celebrate life.  No burr necessary.

Unless I'm missing something I don't think it's possible to thin knives on the top of a Tormek grinding wheel : you would hollow grind it and would not be able to grind at a low enough angle if the knife is in a jig. The jig would bite into the stone.
Theoretically you could use the side of a diamond or CBN wheel but I think it would be extremely difficult, either free hand or using the MB 100(?), this would require a knife jig to hold the knife and it would still catch on the stone.
Someone else may be more enlightened than me and suggest a way to do it.
I just can't see how a Tormek can be used to thin knives.
Once I tried to flat grind a scandi knife on the side of a diamond wheel free hand. It was a disaster!

Actually this is exactly how many Japanese forged kitchen knives are shaped after forging but they generally use a larger radius wheel than the Tormek which will further reduce the hollow grinding.  I have done it and it works but take care to avoid the apex of you will take out big pieces.  Also rocking the blade a bit will effectively grind flat although there will be some inevitable high and low spots.  This can be cleaned up on 220 grit waterstones if needed to give perfect flat or convex.

You do get some of the "benefits" of a convex, for example a soft shoulder, bit of a convex shape, etc.  Of course there'll be some "defects" I said that before too... like you said a bit wavy, etc.

But then is it not better to just thin the knife by lowering the support bar one or two full turns before sharpening, get close enough to the edge and then sharpen at the desired bevel angle height ? That will soften the shoulders, result in a convexish shape, and be much faster and more consistent ?

This is a nice idea but it's liable to have the same tendency to inaccuracies on a different level.  I think if you really care about high precision then it's best to use bench stones to finish.  I've not found a way to rival the precision I can get cleaning up bevels by hand on stones.  When I did KJ-45 convex for a few knives I always finished on stones to get a nice shaped convex. 

So maybe there are weird things going on with your camera, but...

On pics 707 and 708, there are visible indents on the edge and on the black coating (I circled them in red). If they're visible on a low-res pic, they probably are quite obvious irl, and I think polishing would only increase the contrast.

I'd wager they come from the not-so-controlled up-down movement. The fact that it has to be there at all makes it extremely hard to have a smooth movement along the length of the edge. I'm sure you could get rid of those with a lot of practice, but still... If the process introduces an intrinsic weakness, maybe the tooling isn't adequate.

I have seen pixelation in photos uploaded to share online before which look exactly like those dips.  I don't believe the KJ-45 could make hard dips like that, it would likely be more liked rounded holes in the edge similar to half moons.

I have used the convex method with the KJ-45 and while your concerns are well warranted I do believe it's something that can be overcome with proper technique for the most part.  I certainly did not have that issue which the photo suggested.  What I did have was less than ideal blending in a few spots.

Based on what you're saying, a DF wheel should be more of a burden than a blessing (mandatory use of ACC, at least a DE wheel in addition, and still the SJ if you want to polish.

Also some spoon carving knives, but i guess those can't be sharpened with the Tormek.

You might want to look at this video with Wolfgang. I have never sharpened such a tool, and it might require a lot of practice. Wolfgang has a tendency to make complex things look easy thanks to his level of mastery and feeling. The SVM-00 in itself requires quite a bit of experience and training, so ...

Thank you so much for posting this link, I've never seen it. Looks possible but certainly not easy to me!
As for the wheel, I'm almost certain I'll get the normal version of the T-8, just seems more suited to my needs.

I would argue that it's perfectly suited to what you intend to sharpen with it.  Your results will come far more from your skill and understanding of sharpening fundamentals than what you are using for wheels. 

If you are mainly sharpening carving tools then I would definitely agree that a 4000 grit wheel is going to serve you best as a finishing step.  There is no need for diamond wheel considering your tools.

If your main interest was buying the T-8 Black because of the 50 year warranty, well I'd say that's not going to be a factor for most people at all.  If you're a professional sharpener then may be a big deal.