Sharpening plane and chisel blades

[Shedhand]

G'day all!
I've done a search here but can't find a thread which can tell me the optimum grinding angle for carpentry chisels. I've got a nice collection of old EA Berg chisels now and they all need sharpening. I bought a chisel and plane blade sharpening holder thingo for 35 bucks (new cheapy but ok to practice on) I also went out today and bought a green (silicon carbide) Norton grinding wheel for my bench grinder. The thingo that holds the blades for sharpening has 2 angles for each type of blade, chisel and plane. The chisel settings say 30mm for 25 degrees and 40mm for 30 degrees. Which is best or is it some other angle. Do different chisel blade types need different angles. I have a heavy 32mm square sided chisel Berg which I assume is for mortices. Does this have a different angle than the firmer (is that what they're called) chisels the ones with bevelled sides.
What is the concensus (I know that's a stupid question but do your best) on plane blade angles for general all purpose planing of a range of timber of different density/hardness? Don't want to start a long winded acrimonious debate on the relative merits of one set of angles over another or any deep science (I'll get into that later)
Cheers
As usual any advice will be much appreciated.

[Clinton1]

For you sheddie, anything.
Just rub it on the concrete till you get 30mm of blade/chisel left at an angle of 30 degrees one side, 60 on the other.
If you don't like that, just pull another one out of the stash.

Hope it helps




















(No, I'm not bitter about your recent haul )

[mat]

For Mortice and Firmer 30 degrees for softwood 35 degrees for hardwood
Paring Chisels 20 degrees or 15 degrees for very fine work
Utility/Bevel Edge 25 degrees (30 degrees if less than 1/4 inch width)

[Green Woodchips]

I'm with Mat.

I've got my Bergs at 20 degrees for paring, and they work real nice.

But always remember -- no matter what angle you've got 'em at, they'll need to be super sharp to get the real benefit. You'll learn what that sounds like (and feels like) when you're paring end grain with them.

GW

[derekcohen]

can't find a thread which can tell me the optimum grinding angle for carpentry chisels.

For general use, hone the chisels at 25 degrees. This is fine for light mallet taps. If you intend to bash them hard, then go to 30 degrees.

I have a heavy 32mm square sided chisel Berg which I assume is for mortices. Does this have a different angle than the firmer (is that what they're called) chisels the ones with bevelled sides.

I very much doubt that this is a mortice chisel (never this wide for a start, plus I have never seen a Berg mortice chisel and have doubts that they exist). What you have is probably a "firmer" chisel, which is used for framing and heavy work. Hone this at 30 degrees.

My Bergs are honed at 20 degrees but these are thin paring chisels and are not hit with a mallet. They are also reserved for softer woods (not the harder jarrah-type timbers). For hard woods and hammer strikes I use Japanese chisels (honed at 30 degrees). For general purpose work I use Witherby chisels (honed at 25 degrees).

Regards from Perth

Derek

[Shedhand]

For general use, hone the chisels at 25 degrees. This is fine for light mallet taps. If you intend to bash them hard, then go to 30 degrees.

I don't think I've ever bashed a chisel hard. :eek: Hand push mostly with maybe a stray lump of 40x40 tas oak for a gentle tap.

I very much doubt that this is a mortice chisel (never this wide for a start, plus I have never seen a Berg mortice chisel and have doubts that they exist). What you have is probably a "firmer" chisel, which is used for framing and heavy work. Hone this at 30 degrees.

Yeah, I'm confusing my chisel types bigtime. Its been 40 years since my school woodwork classes where we learnt the names and purposes of the various Titan chisels. Must consult my library of woody books and learn whats what.

My Bergs are honed at 20 degrees but these are thin paring chisels and are not hit with a mallet. They are also reserved for softer woods (not the harder jarrah-type timbers). For hard woods and hammer strikes I use Japanese chisels (honed at 30 degrees). For general purpose work I use Witherby chisels (honed at 25 degrees).

Regards from Perth

Derek

Thanks for the advice Derek.
Cheers
PS: Clinton, eat my shorts...

[Shedhand]

IS there any benefit to having a secondary bevel or are the blades too brittle for that?:confused:

[Shedhand]

For you sheddie, anything.
Just rub it on the concrete till you get 30mm of blade/chisel left at an angle of 30 degrees one side, 60 on the other.
If you don't like that, just pull another one out of the stash.

Hope it helps


(No, I'm not bitter about your recent haul )

Actually that's not such a STUPID suggestion mate. My BRAND NEW SLAB IN MY BRAND NEW SHED is fine enough to sharpen (scary) my Bergs....hmm
Thanks for the suggestion mate... you idiot..

[Auld Bassoon]

Actually that's not such a STUPID suggestion mate. My BRAND NEW SLAB IN MY BRAND NEW SHED is fine enough to sharpen (scary) my Bergs....hmm
Thanks for the suggestion mate... you idiot..

Now that's just boasting mate :eek: Try dropping a few lumps of cast iron (eg a few old Stanley's) on the slab - that should get it into shape :eek:

[Andy Mac]

I don't think I've ever bashed a chisel hard.

I have. They can break.


Regards,

[Clinton1]

Worth a try

[dutton]

I have several hand held chisel guides for using on a stone. None was all that good until I bought a Veritas honing guide from carbatec which is excellent.
According to the instructions it recommends a 25 degree angle for all chisels, then a final 30 degree for the tip. The chisel is then turned over and a 10 degree back angle is formed. After you grind the first two angles, feel the edge--there will probably be a very tiny burr. The back angle eliminates this.

MY TIP-- buy a veritas honing guide!!!!!

[Driver]

Don't want to start a long winded acrimonious debate on the relative merits of one set of angles over another or any deep science (I'll get into that later)

Sheddie

Mate! Do you realise what you may have started? :eek: :eek: :eek: :eek: :eek:

[Shedhand]

Sheddie

Mate! Do you realise what you may have started? :eek: :eek: :eek: :eek: :eek:

Yeah I know cobber. I'll just buy the Veritas II and be done with it.

[Schtoo]

I have. They can break.

Been there, got the shirt. :eek:

Whatever you decide to go with, if the edge fails as in cracking, chipping, etc, then up the angle.

My Good Japanese ones are at 30-35, my Marples at 25, the cheapy Chinese ones that I rehardened are at 20, but only for paring and they get freshened up often.

Now go away Sheddie, you are starting to annoy too many folks with these boasts. :mad: