Author Topic: Grinding is stopping too early  (Read 1938 times)

Offline stevens1310

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Grinding is stopping too early
« on: September 30, 2014, 12:09:11 am »
So, I finally worked up the courage to try the planer blade jig.  Pretty straightforward set up, so that wasn't too bad.  I did have to lock the left post first and then crank on the right thumb wheel to get 'er lined up with the the stone, but from what I have been able to read I am not the only one doing that...  ;)

My first set of knives worked like a charm.  They are all FAR sharper than the factory new set I ordered while waiting for my jig to arrive.

On the second set, however, I ran into a problem where - try as I might - I could not get the knives to grind down to the angle stop.  I thought that maybe the stone was glazing over and just burnishing the knife edge, so this is what I tried:

1) I re-surfaced the stone with the fine grader.  No joy.
2) I re-surfaced the stone with the coarse grader.  No joy.
3) I re-trued the stone to expose a fresh new face. No joy - either before or after resurfacing.
4) I started completely over, re-setting everything as if I had never started anything.  No joy.

No matter what I try, there is about 1mm or so of daylight showing between the adjustment screw and the jig hard stop.  And no matter how hard or soft I press, and no matter how long I grind (up to 30 minutes or so, at least...) I cannot advance the grind.  The edge of the blade just gets shinier and shinier - as if I am polishing it, but not removing material.  Just to check things I took off the jig and sharpened a chisel and a kitchen knife - those worked just fine.

I am at a complete loss - and I have this half-sharpened set of knives that aren't doing me any good.  Happily, the first set worked nicely!...

I can see in the forum that others have posted similar problems, but I cannot see any answers.  Any help?  Anyone?  Thanks in advance!

Offline Rob

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Re: Grinding is stopping too early
« Reply #1 on: September 30, 2014, 01:54:10 pm »
I would be very interested in an official response to this too as I have experienced similar problems but also problems related to the wheel simply losing its cutting ability too quickly to come anywhere near finishing the job.  What I found was the only way to keep the stone cutting was to true it with the diamond tool, it glazed over that fast with the large surface area of HSS.  Of course each time you re-true the wheel, you then have to worry about setup because the wheel has reduced in diameter and the setup for planar blade sharpening has very fine tolerances.

It once took me 6 hours to pretty much fail to sharpen my 12" HSS planar knives because of this lack of steel removal capacity on long surface area hard metals.  I'll be honest, I upgraded to the SB wheel after this experience and also due to the need for turning tools and I was so put off by the lengthy experience I've never gone back to it with the blackstone...which should in theory be more hardy than the grey stone for HSS.  I kind of lost the faith after that mammoth session. I should really go back and have another go with the blackstone to check if it makes enough of a difference.
Best.    Rob.

Offline Ken S

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Re: Grinding is stopping too early
« Reply #2 on: October 02, 2014, 02:30:00 am »
I believe we need some help from Sweden on this. We don't seem to have any experienced Tormek planer blade sharpeners on the forum.  Some expertise from the factory would be appreciated.

Ken

Offline stevens1310

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Re: Grinding is stopping too early
« Reply #3 on: November 20, 2014, 04:34:38 am »
I appreciate that others have the same issue - makes me not feel so alone... ;)  BUT - a solution would be even better!  Does no one out there have any guidance to offer?

Offline MakerUnknown

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Re: Grinding is stopping too early
« Reply #4 on: November 20, 2014, 04:46:31 am »
I probably don't but I've been sharpening 12" blades for years on it and have decided that coming to rest on the stop is not that important.  The cantilever design that Tormek uses flexes too much in my opinion to make the stop worthwhile.  I instead resort to holding the blade (and the jig it's secured to) up to a straight edge.  If it's straight and it's sharp I'm done.

Like I say, 12" and smaller.  If you're sharpening a longer blade that requires you to slide the blade down jig then I'm not sure.  I've only sharpened one set of 25" blades and just eyeballed it.
Why your stone is glazing I have no opinion on that.  Mine just doesn't seem to glaze over that often.  I've been using the same stone that came with the machine and I bought in the mid 90's!  Maybe it's a magic stone. :)