Thread: Robert Sorby's ProEdge

Belts are always going to dub an edge somewhat unless they are extremely tight and/or run at slow speed. If you can crank the tension on a belt up so that there is absolutely no slack at a platen, then you can get less dubbing, but to do so is not usually possible with cheap sanders and sharpening machines.

I don't think it's so much the lump that's dubbing your tools, I think it's that when the belt is running, it has a tendency to bunch up in front of a tool (Even if that means it's just lifting a tiny bit) and put a gradual dub over anything you sharpen. It will be hard to eliminate that.

Hard platen and no movement with lots of tension and any speed with a trizact belt can lead to burnt edges.

I don't know anything about the sorby stuff. I'm the kind of person who will spend $300-500 on a sharpening stone, but when some contraption comes out, I get immediately thrifty and won't purchase (did have a tormek, but gave it away to a friend).

Originally Posted by D.W.

I don't know anything about the sorby stuff. I'm the kind of person who will spend $300-500 on a sharpening stone, but when some contraption comes out, I get immediately thrifty and won't purchase (did have a tormek, but gave it away to a friend).

Thanks DW,
I think you are right about the belts bunching ahead of the blade. Unfortunately I'm the "kind of person who will spend $300 - 500 on a sharpening stone" AND buy the new contraption when it comes out! Oh, alright then $100 - 200 on a stone......!
When the Sun comes up I will try a full restoration with ProEdge to set a new edge, Tormek (clone) to hollow the bevel leaving small flats behind the edge and at the heel and then water stone those flats?
If that works then I should have overcome what I see as the problem with the Tormek and water stone combination which is its painfully slow creation of a new edge on a damaged chisel?

fletty

I ditched the tormek and went to a dry grinder. Then a dry grinder with a pink wheel (which is a nice wheel, maybe the best combination of burn vs. finish, but it's a wheel that sheds its particles too fast), and then a dry grinder with an 80 grit CBN wheel. The 80 grit CBN wheel is an animal.

(same grinder in all of these things).

I've got the small kalamazoo belt grinder (I can't remember why I got it, but it is good for freehanding turning tools with the trizact belt), had the tormek (too slow, and always fiddling with it), and set up combination belt disk grinder with a belt, then a cork belt loaded and a leather wheel to power strop. the leather wheel ultimately resulted in shooting a sharp iron across the shop, which was bad.

Anyway, dry grinder and a coarse CBN wheel, it removes metal extremely fast and you really have to be on it a long time for it to actually get hot.

As above, I took an old Berg, 19mm, bench chisel from the stash. The picture quality isn't too good but.....
Chisel before.jpg before sharpening
chisel after 60g.jpg after 60 on ProEdge
chisel after120g.jpg after 120g, notice the edge curving
chisel after 240g.jpg after 240g
chisel after 800trizact.jpg after ~800g Trizact, notice the polishing in the centre only?
chisel after1400trizact.jpg after~1400g Trizact
chisel after2000trizact.jpg after~2000g Trizact

I then took it, with some despair, to the JET wetstone grinder and adjusted it to hopefully provide a witness mark and then a hollow across the centre of the bevel but the bevel was so rounded from the ProEdge that the witness mark was an ellipse in the middle of the bevel...
chisel tormek WIP.jpg

and when I continued on the JET, by the time the ellipse 'filled' the bevel, the cutting edge was straight and the chisel ready for honing on a waterstone....
chisel tormek final.jpg

Right at the moment, I'm struggling to see a role for the ProEdge in my sharpening regime?
I will continue (in the privacy of my shed) in case there is a technique/experience issue but, so far, the only positive I can see is that the process from paint-can-opener to ready-for-honing seemed much quicker that JET alone? It would appear that I could go up to (say) 240g on the ProEdge and then straight to Tormek/JET?
fletty

What are you doing to create the radiused edge,

How are you holding the tool

Are you moving the tool across the belt or holding in the one position.

Just got home from the Rugby, Waratahs v the Crusaders, best game I've seen for years!
Hi Jim,
I figure that any 'dubbing' along the length of the chisel must be the abrasive bunching ahead of the edge and/or machine adjustment but 'dubbing' across the chisel must be technique. I have been holding the chisel against the mitre block to keep it square to the abrasive AND moving it from side-to-side to get even wear on the abrasive and to average out any imperfections. The trial chisel was a bevel edged chisel where the narrow face is against the tool guide and my fingers are on the top wider face. I must therefore be rocking it slightly while moving it from side-to-side. I'll try an old battered firmer chisel from the bottom drawer where the top and bottom faces of the chisel are of equal width and this should eliminate the rocking and hence the curved cutting edge. I'll also clean and possibly lubricate the tool rest in case the rocking is caused by friction and stiction while moving it from side-to-side.
My engineering brain has already designed a jig that will prevent rocking, still present the chisel to the abrasive at the right angle and allow the required side-to-side movement and end to end 'tilt' that comes from the process of removing the chisel material. I might also try, just once, to run the belt the other way so that the cutting edge itself is formed by a retreating abrasive belt NOT an advancing abrasive belt to see if the bunching can impact a less critical surface.
Don't worry Jim, I'm sure that the majority of issues must be technique and I will work on them. I'll make the jig over the next few weeks and send a report on that as well.
time for bed.....
fletty

Hi Fletty

Do yourself a favour and read this all the way through. You will not be disappointed.

http://www.inthewoodshop.com/Woodwor...ningSetUp.html

Regards from Perth

Derek

Hi Derek and thanks again for the link. I've often wondered what, if anything, you can do if a CBN wheel isn't true ...or flat! I'm very keen to try a CBN wheel on the JET and I note that Jim has a 280g flat CBN wheel to suit a Tormek so that may be my next chapter in sharpening ... and SWWW is near?
HOWEVER I am now in a bit of trouble re 'justifying' the ProEdge purchase both to myself and 'others', I need to find its forte for me. I'll work on my technique and demonstrate its value by contributing to the sharpness and hence sale of some of my contentious stash of Bergs and Titans ?
The next trial will be ProEdging a battered old firmer chisel and, provided its edges are parallel, the resuscitation of an old shipwrights (?) slick (re?)found in the back of the treasures cupboard.
fletty

Originally Posted by fletty

The next trial will be ProEdging ........... provided its edges are parallel, the resuscitation of an old shipwrights (?) slick (re?)found in the back of the treasures cupboard.
fletty

chisel slick.jpg

The old slick's slides were parallel and certainly it has enough weight to be more stable on the tool rest which I had also cleaned and lubricated with dry PTFE

chisel slick sfter 2000gtrizact.jpg

I progressed through 60, 120, 240, ~600, ~1400 and ~2000 on the back and then the bevel. I was very pleased with the result and, just to push it a bit, I used a piece of masking tape on the chisel to polish a microbevel with the 2000g only. The whole process took about 7 minutes.
I think my previous curved cutting edge was a combination of 'rocking' and 'fishtailing' both of which were absent with the heavier and much wider slick.
fletty

Hum can I justify some chisels when your done

Agree, but need jig for shorter(worn down)tools and you only get a flat grind
Not to say that they are not good, but that I was brought up on hollow grinding. Drillit.

My reading of the bevel rounding over fletty is that it can be caused by the taped belt join running higher on the platen than the rest of the belt. At the finer grits let the join do the work until it wears down.

And to add re the radiused edge: there's play in the guide; also with a BE chisel there may not be that much of the top to sit solidly on the guide and there's a tendency to rock. The tester in Aust Wood Review ran his BE chisel on the underside of the guide.

Is it worth trying it without sliding the blade back and forth across the belt and instead lift off and place on each side to provide equal wear?
Even with a dead flat back, you will always get some dubbing when sliding the blade.