Thread: Ultimately

Originally Posted by Epicurus

But so far I have not found a fast way to lap the back of my old Titans, and i do not have a lot of patience...

That's it, you need to get some more of that.

More seriously, the dimaond plates are the tool of choice for these operations, there is no quicker way while still maintaining good flatness.

On the other hand (and I should expect flamage for this, I'm sure) you can hollow the backs of the chisels. I've flattened a few old titans and it's the larger ones that are the hardest, obviously. I hollowed the back of a 1 1/4" firmer with an angle grinder farily sucessfully, from there it was a lot easier to flatten.

**ducks for cover**

I find it interesting that woodworkers in the UK tend gto love diamond stones, while those in the USA tend to critisize them for their short lifespan. The latter do not recommend them for sharpening blades. I come across many complaining that they destroyed their DMTs trying to flatten the backs of chisels. I tend to lean in their direction.

Throw away your 300. It is a dangerously unreliable stone (hollows rapidly). You do not need it if you have a wet grinder.

The best way to flatten the backs of chisels and plane blades is to lap on sandpaper glued to glass.

Lapping the Backs of Blades

There is nothing wrong with King waterstones. They work very well and were the standard for many decades. Some prefer the 800 over the Shapton 1000.


My sharpening strategy: I would use this to create a hollow grind at 25 degrees (increase this later if the steel cannot cope), taking the hollow right to the edge of the bevel. No secondary bevel will be used.

Once this is done, you only need a couple of swipes on a 1200 waterstone (to straighten the edge), and finish on your 10000 waterstone. Balance the bevel on the hollow and you can do this freehand. You will create a fine microbevel, and you will be able to re-sharpen this many times before regrinding.

What is wonderful about the wet grinder is that it keeps the heat down and you can grind to the very edge of the steel without fear of changing the temper.

The reason I recommend that you hold at the same angle that you grind is that this maintains a coplanar flat bevel, which you can use bevel down with registration across the bevel. You cannot do that if you introduce a secondary bevel.

Regards from Perth

Derek

I've recently - intermittently, over the last month - been flattening the back of a 50mm Titan using a green King stone - 300grit - or maybe its 280grit.

I have to agree the stone is not up to the job. My process, so far, has been to rely on "Patience". I have spent hours at it so far and I'm almost there.

But the green King stone hollows unpredictably. Some parts of it are hard and don't dish much and in other places it seems to hollow out quickly. Maybe it's glazing in places and hollowing in others. Anyway, it really is testing my patience.

I used to use the scary sharp method before I got my waterstones, but don't like it much. I found it very easy to round the edge. As others have reported the paper tends to bunch up in front of the blade a bit and not stay flat. You can't see it happening.

However, as I've been working on the stone (flattening it every couple of minutes) I have been tempted to get the glass plate out again - remembering not to push the blade forward - sideways would be best.

... Titans - don't you just love them - but dang they're hard!!

Originally Posted by Epicurus

But so far I have not found a fast way to lap the back of my old Titans, and i do not have a lot of patience.

The picture below is a Butcher cast steel chisel more than 2" in width. It was sharpened on a Lap-Sharp to a 1 micron finish. You can quickly flatten chisels and plane irons to this level. It is best to use the system wet, as mentioned in this thread, it keeps the tool cool to prevent thermal damage to the tool edge. You can bid on one in the Bush Fire Auction.

Originally Posted by kman-oz

On the other hand (and I should expect flamage for this, I'm sure) you can hollow the backs of the chisels. I've flattened a few old titans and it's the larger ones that are the hardest, obviously. I hollowed the back of a 1 1/4" firmer with an angle grinder farily sucessfully, from there it was a lot easier to flatten.

**ducks for cover**

Oh thank you Sooo much Kman. I pulled out my little ozito multi tool and saved many hours of needless flattening. I thought of this before but I was too sacred to say it out aloud.