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Tormek Supergrind - Starting Over

Started by Rick_B, October 12, 2019, 09:32:19 PM

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Ken S

Good discussion. I happen to have two SG-250s. I used the TT-50 light and slow on one. I used my Sharpie on the other to divide it in half. I used the coarse stone grader aggressively on one half. I used a "coarse" diamond file card on the other half. Judging by feel, the coarse stone grader and the coarse diamond file card seemed to be about the same. Neither seemed as coarse as the TT-50.

A good follow up test would be to use the TT-50 slowly on half of the grinding wheel and fast on the other half. There is much to be learned about the grading process.

Ken

Rick_B

So in my efforts to reacquaint myself with the Tormek I decided tostart with the largest chisel I have (1-1/2") because I was having some trouble with smaller chisels.  I got through the grinding process with what appeared to be a uniform scratch pattern.  However, after honing on the leather wheel there were scratches that wouldn't go away.  I'm thinking I didn't do a good job with the fine side of the grading stone.  So how long do folks spend doing the fine grading?  How much pressure should be used?

I have read where folks are using other diamond type stones for grading but it seems the Tormek stone should be satisfactory.

Thanks
Rick

Ken S

Rick,

As part of my testing CBN wheels several years ago, I tried taking one of my Blue Chip sharpening chisels directly from my 80 grit CBN wheel to my leather honing wheel with lots of PA-70 honing compound. A long time with the leather honing wheel reduced a surprising amount of the scratches. The chisel was sharp, not super sharp, but quite usable. As a control test, I also sharpened an identical Blue Chip 3/4" chisel using the traditional three step technique. The three step chisel both looked and tested sharper.

This test illustrates the value of having multiple identical sharpening chisels. These are valuable learning tools. Many questions can be explored. What is the difference between using the finely graded SG for fifteen seconds and a full minute? The same question with the leather honing wheel. Having multiple sharpening chisels allows you to observe the process at several stages and using different processes (and different pressures).

Do not be afraid to experiment.

Ken

Rick_B

So Ken - following your suggestions - I went back to same 1-1/2" chisel.  I regraded the stone with the fine side of the grading stone and was conscious of spending a little more time with it.  Then I resharpened the chisel until I had a uniform scratch pattern.  Finally I honed it and spent a lot of toime at that - I was still having trouble eliminating all of the scratches.  I adjusted the USB to lower the front of the chisel just a bit.  That helped a lot but there are still some visible minor scratches when viewed in the right light.  It is likely good enough for the woodworking I do.

Rick

Ken S

Rick,
Two suggestions:
I was curious to see if using the stone grader (fine side) for a longer period  would make the stone grit even finer. My test results are somewhat iffy, however, longer time did seem to help. Try grading with the fine side for approximately ninety seconds.
Stig gave me a good suggestion. Finish with very light pressure. Grepper posted some photos of this a long time ago. I don't know what happened to them. I would definitely suggest trying to end each phase of sharpening with a light touch. Note that this is not a recommendation to use the SG with light pressure all the time, just the last few seconds.This is one of the benefits of having several "sharpening chisels". It is easy to make side by side visual comparisons.
Ken

jeffs55

If there are still scratches on it either you need to spend more time honing or use a more aggressive honing compound. Since you seem to be tired of the honing, I would go to a more aggressive method. Use a polishing compound with a coarser grit than the Tormek paste. Tormek polishing compound is approx. 3 microns which is about 8000 grit. Go to 4000 grit compound or coarser. 3M has a 3000 grit and most likely everyone else too. Maintain your bevel at all costs as in keep it flat against the compound backing. Do not curl it when completing a pass. This is what I would do if it bothered me all that much which it would not.
You can use less of more but you cannot make more of less.

Rick_B

Ken - that sounds like a couple of good ideas - 90- seconds with the fine stone and lighten up at the end of the shrpening cycle.  I'm gong to gove both of those a try.

Jeff - I have both the Tormek compound and Dursol - I have been usng the Dursol so far.  I agree that I could easily walk away from the current level of scratches and call it good.  At this point Im calling it education and an opportunity to practice :)

Thanks
Rick

Rick_B

Well I've been practicing with chisels and have gotten through 15 or so.  I tried Ken's ideas  and discovered that a longer tme with the grading stone did provide a finer finish.  It seems that 60 seconds gets a  fine finish and another 30 doesn't seem to get much improvement.  This is based on observation - feel and sound - of the regrading process.  I also tried lightening up at the end of the sharpening process.  As a result I was able to sucessfully sharpen the chisels - they are not perfect/still had some visible scratches but they shaved arm hair and slit paper so I am calling them good.

I still have some issues with keeping the bevel square with the chisel edge.  I'm not sure how to check squareness with the chisel installed in the edge guide - I don't have a small enough square to do that so I am relying on visual observation - not always the best method.

I have a couple of more chisels to complete then I am moving  on to turning tools.  Any suggestions/ideas are appreciated.

Rick

Ken S

Rick,
For turning tools, make sure you have the much improved SVD-186 gouge jig and the Tormek TNT-300 Turner's Information Box. The new gouge jig is a real improvement and the Info Box is Tormek's best video.

Ken

Rick_B