Plane (and sharpening) training?

[sploo]

You should find them easiest of all to sharpen freehand. The width of plane irons means they register particularly well on your sharpening media.

With the narrowness of many chisels or some narrow cutter there's the possibility of rocking side to side as you sharpen, creating a slightly cambered or rounded profile which is not usually desirable. Perversely, on plane irons where they're unlikely to happen by accident you might actually want a camber on your edge!

I know what you mean about the camber - the first time I sharpened my #4 plane iron I didn't put enough (well, any really) camber on the corners and it was creating steps when I planed.

Having seen Sellers' video on sharpening a plane iron it looks as though he puts way more of a round on the corners than I've done, so next time I'll be a bit more aggressive with it (and obviously I'll do that with the #4 1/2 iron when it turns up).

 

[bugbear]

Consider me a convert to not using a honing guide.

The only thing I've not attempted yet is a plane iron. I have a Stanley #4 1/2 on its way from another eBay purchase, so we'll see how that one goes :wink:

Hand honing is easy - just after grinding.

The difficulty, mentioned in all the old texts, is that the bevel angle tends to get
a little steeper every time you do it, so you eventually need to regrind to lower it again.
The difficulty is making sure that each grit gets as far as the actual edge,
and doesn't just polish the bevel, so you tend to - just a bit - raise
the angle "to be sure". Of course, removing metal from the edge itself
is really fast, so the angle tends to creep high and higher.

This is not a fundamental problem, just part of the hand honing
"context".

BugBear

 

[ED65]

Having seen Sellers' video on sharpening a plane iron it looks as though he puts way more of a round on the corners than I've done, so next time I'll be a bit more aggressive with it (and obviously I'll do that with the #4 1/2 iron when it turns up).

Yes you've got to take the corners off at least but I'm not a fan of Paul's method for this, it's not that the rounding is excessive it's just that the conventional way to knock the corners off is much simpler and faster for anyone with relatively little experience.

You basically just drag each corner of the iron across the abrasive while rotating it a bit in your fingers. If you're sharpening on a stone it's sometimes best to use the side of it so that you don't risk scoring the face of the stone, particularly important with softer waterstones.

 

[Bluekingfisher]

I can see the merits in both free hand and jig sharpening. For me it is by use of jig (in the main) chisels and plane irons are sharpened this way (LV MKII) it provides repeatability, quick to use and removes minimal material from the iron.

As BB mentioned, free hand sharpening for me seemed to increase the angle very quickly which required frequent re grinding of the iron, not a real problem as I have a Tormek, although I cannot but help wonder how quickly I am grinding irons away.

All other edge tools I sharpen free hand. I use diamoid plates with baby oil as the lubricant, no rusty plates, nice smell and soft hands



David

 

[Jacob]

.........
The difficulty, mentioned in all the old texts, is that the bevel angle tends to get
a little steeper every time you do it, ......

Only if you want it to. The rounded bevel "dip as you go" avoids this.

The difficulty is making sure that each grit gets as far as the actual edge,

You do this by feeling the burr. If you can't feel the burr right across after a minute or so you need to go to a coarser grit.

...., removing metal from the edge itself
is really fast, so the angle tends to creep high and higher.

Only if you let it

 

[sploo]

.........
The difficulty, mentioned in all the old texts, is that the bevel angle tends to get
a little steeper every time you do it, ......

Only if you want it to. The rounded bevel "dip as you go" avoids this.

The difficulty is making sure that each grit gets as far as the actual edge,

You do this by feeling the burr. If you can't feel the burr right across after a minute or so you need to go to a coarser grit.

...., removing metal from the edge itself
is really fast, so the angle tends to creep high and higher.

Only if you let it

It did occur to me that the next time I sharpen I'd have to be very careful to not just rock the tip further (I suspect it'd be easy to just keep rocking forward and hitting the edge - but then making it steeper over time). That said, I suspect a bit of work at a slightly lower angle on a coarse grit would help.

 

[D_W]

It did occur to me that the next time I sharpen I'd have to be very careful to not just rock the tip further (I suspect it'd be easy to just keep rocking forward and hitting the edge - but then making it steeper over time). That said, I suspect a bit of work at a slightly lower angle on a coarse grit would help.

100% accurate - fast stones for coarse grit (like crystolon, etc) and slower stones for fine grit will help you not commit the mortal sin of just rolling it up "a little more" to get the edge.

A grinder and a single stone for a while (a washita is my preference) eliminates chasing the angle steeper in progressive stones. There is only one angle to learn and you never have to deviate. If you need just sharper than the washita for something like a paring chisel, a burnisher like jasper does a fabulous job without removing much metal, so there's little sin to correct for next time.

 

[sploo]

I sharpened the #4 1/2 plane iron this evening. Getting the back face flat was a pig - it had a pretty major hump, and even the "hit it with a nylon hammer" trick didn't work. Quite a bit of grinding with a bobbin sander (and a lot of elbow grease) and it's acceptable. Very glad I only need to do that once.

By comparison, the bevel was unsurprisingly easy. Of course, when I cut my lapping film sheets for the scary sharpening system I did them at 60mm, as that was bigger than my #4 iron. I'm sure you can spot the problem ( :wink: ) but it worked out OK in the end.

The striations are the reflection of my garage ceiling - it's a nice mirror finish and cuts well.

 

[Jacob]

I sharpened the #4 1/2 plane iron this evening. Getting the back face flat was a pig - it had a pretty major hump, and even the "hit it with a nylon hammer" trick didn't work. Quite a bit of grinding with a bobbin sander (and a lot of elbow grease) and it's acceptable. Very glad I only need to do that once.

Waste of time. No need to flatten the back as long as the cap iron fits well at the edge. Flattening is a bit of a pointless fashion with the new sharpeners.

 

[David C]

Well Leonard Lee and countless others disagree with you.

Leonard's book has photos to prove it.

The quality of an edge is the product of the meeting of two surfaces.

If the back is crap the edge will be crap.

The "new sharpeners" are a figment of your feverish imagination.

David Charlesworth

 

[Beau]

To be fair Jacob said it didn't need to be flat but didn't' say it wasn't polished to the same degree as the hone. Personally think honing the back with a flattened blade is far easier job but hay ho.

 

[Jacob]

....
The quality of an edge is the product of the meeting of two surfaces.

Yes but only AT the edge. It doesn't matter too much what's going on further away

If the back is rubbish the edge will be rubbish.

Why? There is no particular logic in this.

 

[ED65]

I think a little more detail might be beneficial here:

 

[Jacob]

I think a little more detail might be beneficial here:

Yes exactly! And it doesn't even need to flat - it can be rounded, or have a back bevel etc. As long as the cap iron fits and the edge itself is OK.

 

[D_W]

Well Leonard Lee and countless others disagree with you.

Leonard's book has photos to prove it.

The quality of an edge is the product of the meeting of two surfaces.

If the back is rubbish the edge will be rubbish.

The "new sharpeners" are a figment of your feverish imagination.

David Charlesworth

I've noticed on irons that the only ones that have trouble getting a good edge (whether they are polished hard or not) are those that are out of whack enough that the finish stone cannot push a wire edge back toward the bevel when working the back.

I have experimented, as I said on other threads, I learned to sharpen from your video and followed the method to the dotted i's and crossed t's. But since then, I have prepared irons in planes and chisels while intentionally leaving the back a bit short as long as it was flat enough to affect the wire edge, and I haven't noticed a great deal of difference in the level of sharpness as long as the wire edge is completely removed.

That is, hypothetically if I left the relatively fine mill finish on a good piece of steel or a decently made vintage iron (as opposed to something like the new stanley irons with big mill marks on them), I don't know if someone could tell which plane has the black flattened if I prepared two.

It does require a fine abrasive to remove the wire edge without having the back worked.

I have seen other people write on it (bob rozaieski comes to mind). For a beginner, it's safer to polish the back to the edge, because there will be no judgement needed in knowing what's a problem and what's not a problem.

I may indulge myself later and make a video of this at some point, but I don't know if I want to encourage people who don't know enough yet about sharpening to start asserting that you don't need to polish the back of a tool (because that's what someone will say, even if only 3 people watch one of my videos).

On something like a straight razor, though, this would not be acceptable. I was not aware of just how sharp and properly prepared something like a straight razor needs to be until I started shaving with them. But polishing one side of the bevel, as long as the wire edge can be removed, will very easily shave hair and do something like take a 1/2 thousandth shaving. I won't be able to prove that until I make another plane, because I don't have an iron in any plane that hasn't had the back worked.

 

[Jacob]

.........
I've noticed on irons that the only ones that have trouble getting a good edge (whether they are polished hard or not) are those that are out of whack enough that the finish stone cannot push a wire edge back toward the bevel when working the back. ......

You just have to lift it a touch - effectively putting a very shallow bevel on it. No point in flattening the whole face. All the old plane irons I've looked at are done that way - never a flat faced one to be seen, still less a polished one.

 

[D_W]

.........
I've noticed on irons that the only ones that have trouble getting a good edge (whether they are polished hard or not) are those that are out of whack enough that the finish stone cannot push a wire edge back toward the bevel when working the back. ......

You just have to lift it a touch - effectively putting a very shallow bevel on it. No point in flattening the whole face. All the old plane irons I've looked at are done that way - never a flat faced one to be seen, still less a polished one.

Yeah, and a lot of moulding plane irons done that way that I've gotten a hold of, precisely enough that I doubt it was by accident.

I have seen george wilson for years refer to lifting the iron only just on the back when finishing it. I know of no finer maker of anything.

I err on the safe side and bias pressure instead of lifting, but no longer polish the back of an iron to a bright polish on a newly acquired plane. If had a plane where a tiny lift would do it, I would do that (I don't at this point).

 

[sploo]

I think a little more detail might be beneficial here:

Yea, sorry I should have been more clear; what I meant was that the back of the iron was convex such that it was very difficult to flatten the tip. I had to grind the area behind the tip before I could persuade the tip to flatten on even the most coarse grit I had. Not that hard with a chisel, but it took a while on a plane iron. Hard work, but you only need to do it once. Exactly as your photo above.

 

[David C]

Jacob has not been paying enough attention.

Many authors recommend just a 1/4 " or even 3/16" of flat polished back, adjacent to the edge of a plane blade. In fact anything continuous across the width will do.

Fit of cap iron is one reason.

Quality of edge is another, and this relates to correct polishing off of wire edge. Something which did not happen readily on a "fine" India stone. Hence the crude methods for tearing off the wire edge and subsequent stropping.

Of course there is logic. Think of a toothing blade. Get Thee to the library and look at the electron microscope photos in Leonard Lee's book "Sharpening".

David

 

[D_W]

I have that book already. If that was for me, I understand more about sharpening than you may think, and I have a microscope in my storage area that i've used to examine results.

I forgot, I do have a coarsely made buck iron, one of the ones that are sold at department stores here for $3. I'll do exactly what I suggested above, and sharpen only the bevel side, unless it is extremely coarsely made and then I may sharpen the back with a medium india and leave it there and work on the bevel side.

I guarantee it will leave a bright surface on wood.

I'm not advocating that for beginners. I'll tell you my sharpening method - oilstones with only the bevel side worked by a jasper and then stropped on bare leather only. Put your bets in at Lloyds.