Replies

1. 
   lwilliams | Jun 22, 2009 04:31am | #1

   Jerry,

   We've tried diamonds and everything else we heard about or could dream up. We do use diamonds for some things but, for flattening irons or chisels, they're slow and frustrating. As an abrasive diamonds are amazing, they'll cut anything. Their main draw-back is they're slow cutting--really slow compared to other abrasives of similar grits. I believe this is the result of their faceted soccer ball shape when most abrasives are shaped like jagged icebergs.

   I don't know what to say about flattening A-2. The only real place I've seen the abrasion resistance of the stuff show up was in maintaining a flat face/back of edge tools. You've hit on one of three reasons I don't use tools made of A-2. You may see a very slight difference in edge holding but that limited little bit doesn't come close to making up for the increased sharpening time. I don't think it's a coincidence nearly every fan of A-2 steel I've met thinks the "ruler trick" is a great idea. Dubbing, whether intentional, from edge wear or from out of flat stones is something I try hard to avoid.

1. 
   nazard | Jun 22, 2009 05:00am | #2

   Thanks, Larry!  I will admit to a bit of frustration with the last bunch of A2 irons I purchased.  Takes FOREVER (at least to me) to get the backs flat and polished.  RE the Ruler Trick: I have frequently used it on old irons that have pitting too nasty to bother with.  I have not used it on good condition or new blades.  

   -Jerry

1. 
   derekcohen | Jun 22, 2009 05:19am | #3

   Hi Jerry

   Several years ago I would have argued that high carbon steel was the only thing for me. Frankly, in hindsight, that was because i had limited experience with A2 steel. These days I use A2 as much as O1 and W1 and will say that it is a better steel for me. That does not mean it is a better steel for all - it is just that I work with more abrasive and harder woods than the average woodworker. I would say that my experience is quite typical of Australians, some of whom are looking even further afield to steels like HSS and D2. I am wary of the latter two in common woodworking tools (that is, outside of lathe chisels) since, although they hold an edge longer, they are a bear to hone, and this translates to a psychological resistance to sharpening.

   The thing is that A2 is no more difficult to sharpen than O1 if you use the appropriate methods. In my book this is to avoid using full face bevels. Instead, always use a microbevel. This may be done either freehand on a hollow grind, or as a secondary bevel on a flat primary bevel. The amount of steel that needs to be removed is minimal, and one only needs a few swipes over your choice of media (waterstone or diamond I know about. Oilstones I have not used).

   I use the Pro series Shapton ceramic waterstones - which are not the versions prescribed for A2 - which work exceptionally well.

   When it comes to diamonds, I have used paste on steel plate and on hardwood, and it works pretty well. However I do not find that it works as well as sandpaper when it comes to the low grits, and I am also concerned that (as in the case of my Coarse/Extra Coarse DMT plate) the diamonds will wear. Still, I do use the Coarse plate for blade backs and it works pretty well. The thing is that it is only 325 grit and the sandpaper can go down to 80 grit, which is preferred for fast removal. I have tried the equivalent in diamond paste, and it works, but I have limited time doing so and would not want to generalise to much from this. I really need a decent lapping plate to do it justice.

   Regards from Perth

   Derek

1. 
   nazard | Jun 22, 2009 05:46am | #4

   Thanks, Derek!  I may order the flattening plate and give it a try.  My concern is that the plate will wear and need to be flattened, thus leading to the purchase of a flattening plate flattener and possibly a flattening plate flattener flattener....  I am currently using alum oxide and wet/dry paper on a granite plate, which certianly affords good results.  I am, however, under the impression that the diamond paste/steel lapping plate system is much more aggressive.

   -Jerry

2. 
   gb93433 | Jun 23, 2009 07:12pm | #5

   I made a flat plate using mild steel which was 1/2" x 3"

   To flatten plane irons I start with an 800 grit waterstone and then finish with finer and finer grits.