Well folks
I installed the blackstone and ground a factory fresh HSS deep flute bowl gouge to a good fingernail grind. Specifically to jig setting 4 (55deg)' protrusion 65mm, hole A on the tts.
So not quite Ellsworth but a good deep fingernail grind. The blackstone had the wings a good 3/8" back in no time. Total grind time to back on the lathe from out of the sleeve was about 12 minutes.
Not bad at all. I wore high magnification reading glasses and could see the steel flying off the tool. I'm happy again :-)
I still have a realistic expectation for modest speed on the planar blades but that will be the next test. Was really chuffed with its first tour though
Rob
Well done, Rob!
Ken
I bet planer blades are next, but if you get a chance I'd be interested on how it works on regular steel. Is it too aggressive? (The product info says no). Any disadvantages? Like we were talking about in the other thread, it's claimed to offer "exceptional wear resistance".
I've got some knives that are really tough stainless and resist sharpening. I can get 'em sharp, it's just a lot of grinding and pressure. I wonder how it would work on that those.
Hmm... I wonder if it excessively wears on the truing tool?
Thanks for letting us know about your progress!
I read somewhere that these harder steel knives are typically sharpened on wet stones only, no leather stropping.
A sushi chef told me that he sharpens his knife every night using just a wet stone.
Incidentally, on a purely aesthetic level, the blackstone looks very sleek in its dark livery ??? Go faster stripes are all it needs to "pimp my Tormek"
Quote from: grepper on February 26, 2013, 01:29:15 AM
I bet planer blades are next, but if you get a chance I'd be interested on how it works on regular steel. Is it too aggressive? (The product info says no). Any disadvantages? Like we were talking about in the other thread, it's claimed to offer "exceptional wear resistance".
I've got some knives that are really tough stainless and resist sharpening. I can get 'em sharp, it's just a lot of grinding and pressure. I wonder how it would work on that those.
Hmm... I wonder if it excessively wears on the truing tool?
Thanks for letting us know about your progress!
Hi Mark
I've not actually tried it yet. The 12 minutes on the bowl gouge didn't need it. Having just had a look this morning though I notice it is channelled in the centre where the point if the gouge has grooved it. I will true it later and test that. I did all my knives at the weekend so can't do them again.
Tell you what, ill try my bench chisels, they could use a tuneup and they're regular softer steel. Ill report back
Cheers
R
Good field work, Rob.
In his excellent book on sharpening, Ron Hock makes the comment that he uses carbon knives in his kitchen. He states he hasn't needed to use more than a steel on them in years of use. Interesting that someone of his knowledge and experience hasn't bought into the marketing nonsense of needing knives which won't stain when cutting onions.
Ken
Thanks Rob. That will be interesting. Interesting too is that you channeled the surface with the gouge.
BTW, while it somewhat greeps me out, I can think of some quick and easy scenarios of how you could use the T-7 to "prepare" your knives for a proper sharpening again. :)
_All_ of my stuff is sharp. I even pulled the blades from my oddly large collection of those grey handled utility knives with the sliding blades, and sharpened those. Now what???
Mark
8)
I recall when I first got the T7. I did all my stuff and eventually ran out of things to sharpen. It was around that time my friends and family started benefiting enormously :-)
All of my mother-in-law's knives are sharp. The wife works at a nursery. All of their pruners are sharp. (For free!). I had my house resided. The siding crew left will all of their tin snips sharp. Now what? :'(
Haha that's funny Mark. You should start charging old sport, they do say you should make your passion your work to find true enlightenment.....maybe that's destiny trying to tell you something???
I could just see me sharpening scissors door to door...there you are madam...and would you like any natural edge bowls turning while I'm here :-)
Well I trued the blackstone this afternoon for the first time. Absolutely no different to the SG. Procedure and ease were identical
I then deliberately sharpened a carbon steel blade to see how it cuts. I mounted my Stanley bailey smoother plane iron with the square edge jig. It had a couple tiny nicks towards one side. It was dull. I ground the whole bevel at 24 then a micro bevel at 25.
Couldn't believe it.....cuts like butter. I actually counted the passes, 16 passes with very light pressure and the whole bevel was done. I was gob smacked.
Regraded with the 1000 grit, that seemed easier than the original stone??? How can that be?? Four passes and it was done
Honed, bobs your uncle.....sharp as my old headmaster!!
Extremely impressed with this puppy so far. I also checked the wheel with a straight edge and it was still true. Mind you, it hadn't really done any work :-)
Brilliant. Love it.
Rob,
Well how cool is that? I guess time will tell, but it sure sounds like it is nothing but an improvement to the SG. Maybe there are other reasons, but it almost sounds like Tormek should just bail on the old wheel and start shipping these hot black ones!
Thanks for checking that out and letting us know.
Mark
Yeah Agreed. Why wouldn't they....oh hang on....it cost £138. Now I remember. Ouch...Im getting far too cynical in my old age :-)
Quote from: Ken S on February 26, 2013, 11:55:43 AM
Good field work, Rob.
In his excellent book on sharpening, Ron Hock makes the comment that he uses carbon knives in his kitchen. He states he hasn't needed to use more than a steel on them in years of use. Interesting that someone of his knowledge and experience hasn't bought into the marketing nonsense of needing knives which won't stain when cutting onions.
Ken
Ken,
It isn't as much "marketing nonsense" as bureaucratic nonsense. Stainless blades and plastic handles are now mandatory in all commercial food processing. As goes industry, so goes consumer goods.
Good point. I hadn't thought of that.
Ken
I wish Jeff would chime in here. Is the SG-250 just a more expensive and better alternative to the SG-200?
Is the lower cost the only advantage to the SG-200?
Herman,
Don't know if you're getting your part numbers mixed up, but an SG-200 is exactly the same material as an SG-250. The SG-200 is 8" diameter and about an inch and a half wide. It's the replacement stone for the T-3.
Now as for the SG-250 original stone compared to the SB-250, in theory, the SG-250 should handle carbon steel tools like chisels and plane irons better than the SB-250, which is formulated for HSS. That theory stated, Rob is not the first person whom I've heard from who felt the SB-250 performed well on carbon steel. Grading is not as effective or as quick on the SB-250, that I can vouch for.
That's interesting input Jeff, re the grading.
Because I'm so early into my experience with the SB-250 I've only trued it once and graded to 1000 grit once. I must say I found the grading to 1000 grit a doddle. I couldn't discern any difference between that and the old stone? It must be going to 220 that's harder I guess. That would make sense, reactivating a harder stone has to require greater effort.
I also don't quite get the logic behind it not performing as well as a softer stone in a softer material (carbon steel). Wouldn't the fact it's formulated for HSS mean it cuts softer materials more aggressively?
Rob, if the SB can't be graded as effectively it seems to me that it wouldn't perform as well in areas where that's a factor. For example if you're sharpening a thin (carbon steel) kitchen knife you want the stone graded to as fine a grit as you can get. As Jeff is fond of saying, smooth as glass.
Then, if you want to sharpen your (carbon steel) lawnmower blade you're going to want to switch back to the course grit.
Of course, if you have both stones you could use the SB on your lawn mower blade quite effectively. But having both stones is not the comparison we're making here. But since you now do have both stones you can easily switch between them. Use the SB when you want to take off a lot of steel, use the SG for touch ups when aren't removing a lot of steel and you want to get that smooth mirror finish.
Jeff, yes I had my part numbers mixed up. I was comparing the SB-250 to the SG-250. Thanks, maybe I'll buy the SB-250 the next time I need a present for myself!
When Jeff said it can't be graded as effectively I assumed he meant its more difficult (effort) and time consuming to switch between 220 & 1000. I didn't think he meant it would be less effective at cutting once it had arrived at either of those grits? But perhaps you've hit the nail on the head Herman
What I still don't really understand is why.......why wouldn't a stone formulated to cut a hard material (HSS) not cut a softer material (carbon steel) as well? Surely it would cut faster?
Rob, you're spot on. What I meant was that it is harder to change, but you're right, it is just as effective once graded.
I'm not an abrasive engineer, nor a metallurgist, so I can only pass on what those who are have told me. It has to do with the softer steel gumming up the silicon carbide surface more than the aluminum oxide surface.
Herman, just to clear something up in your post, SB=Blackstone=HSS SG=Original=Carbon Steel.
Ok thanks fir that Jeff. Maybe the carbide surface has harder and finer particles, so it has the "valleys" fill up with swarf faster? Like you I don't know. It sure did well on the carbon steel plane iron though so for practical purposes I guess it doesn't matter.
Ill still report on the planar blades when I do them but for right now I'm impressed with the blackstone
Quote from: Jeff Farris on February 27, 2013, 05:03:58 PM
Herman, just to clear something up in your post, SB=Blackstone=HSS SG=Original=Carbon Steel.
Dang, that's two in a row. Ok, I went back and fixed it.
Just out of curiosity, would it be possible to purchase the T7 equipped only with the SB-250 HSS grindstone?
Unlike most here, I've never experienced the joy of woodworking. So, when I purchased my T-7 I asked if I could get an alternative assortment of jigs. The answer was no. It comes prepackage from the factory.
As I remember, I had to purchase the scissors jig separately.
It would be interesting if Jeff would chime in here, as to if there is any benefit at all with the SG over the SB.
From this thread, I have yet to see any benefits of SG over SB other than grading may take longer with the SB.
Why not try a small project Mark. You might just love it. :-). Nothing like the smell of freshly planed pine or having your entire torso covered in foot long green oak shavings as you hollow out a bowl.....ah....marvellous :-)
As I mentioned in an earlier post, the SG is considered to have a wider application than the SB. It handles normal carbon tool steel better than the SB and still will cut HSS. It is a better choice as the foundation of the system.
Jeff, got it. That makes sense. Thanks. Sorry to have missed the earlier post.
From what Rob said, the SB did a gobsmackingly good job on normal carbon steel, but that is just a one person, one tool experience review. Maybe the SB loads up with a lot of normal carbon steel use?
But I'll willingly take your word for it! So maybe it's "Bob's your uncle" on the SB/SG debate.
Rob, thanks for the new expressions "gobsmacked" and "Bob's your uncle". Being from the US I had to Google both. :)
Haha...no worries. I've got plenty more where they came from
I must say I've borrowed a few from you folks over the years too. I've done a lot of business in the US and have been collecting your expressions for a long time.
No one here says " I'm done" very often, that's every day language in my household. I've found Americans have a lovely way of shortening English language to convey all the meaning but in perhaps just two words. That sucks! Being a classic example :-)
I love those quick summary phrases you guys have invented