How to sharpen?

[stuartpaul]

For as long as I can remember I've been pretty cr@p at sharpening. Only the purchase of a Tormek meant I could stop using a lump hammer with chisels :shock:

Trouble is I now wait until they are as blunt as old boots (usually after opening the fifth tin of paint!) and then put them pack on the wet stone. And so the cycle continues.

This is neither good for the tools, my work or my fingers (wana see some scars?!!) so I'm looking to find out more about 'proper' hand sharpening. I'm not (too) much of a moron and understand some of the basics but do get confused about micro bevels etc. and sometimes feel people try and make it a science when it probably isn't.

So, - what I'm looking for is a simple guide to hand sharpening bearing in mind I have access to the Tormek to get initial angles right.

I was looking at the scary sharp stuff from another thread and that looks really good but will it be ***** proof? I know I need to just get on with it but I'd also like to properly understand some of the science.

Anyone able to point me in the right direction?

 

[Krysstel]

The simple answer for me was :-
***** proof = Worksharp

As close as it's possible to get IMO

 

[wizer]

Yes scary sharp is ***** proof. You will need a flat surface like float glass or granite and I'd recommend a honing jig like the Veritas MkII. Then it's extremely simple. Use the Tormek to get your primary bevel and hone regularly on the abrasive paper as you go. Simples

 

[wizer]

You can see the veritas jig in action in this video

http://www.youtube.com/watch?v=iDoRLdR4zC0

Gidon's using diamond stones but you can hone on abrasive paper in the same way.

 

[woodbloke]

I was looking at the scary sharp stuff from another thread and that looks really good but will it be ***** proof? I know I need to just get on with it but I'd also like to properly understand some of the science.

Anyone able to point me in the right direction?

I'll be doing a review on the Hand Tools forum on this method of sharpening fairly soon. Whilst Tom is correct in saying that the Veritas MkII (and others) can be used with the plate glass system, the roller is always rubbing on, and therefore wearing away the honing medium whatever you use, be it a diamond stone or soft waterstones :shock:
There's nothing difficult or even scientific about honing but it's fair to say that it's the fundamental thing to learn and get right if you intend to do some better quality work as opposed to wood 'butchery' (no offense intended) As is always the case though, each individual needs to play around with all the different methods, so what may suit one may be anathema to another - Rob

 

[matthewwh]

Sharpening divides neatly into two topics, grinding and honing. Grinding refers to the preparation of the primary surfaces, back and bevel, honing refers to the much more accurate preparation of the last mm or so of each of those faces to form a cutting edge. If the grinding is right, honing should take a couple of minutes maximum, once you have it down to this sort of timeframe you will find yourself wanting to sharpen your tools the moment you feel the performance start to fade. A sharp tool is a beautiful thing to use, it cuts with very little effort, which in turn means that you have maximum control.

If you already have a tormek you are pretty much tooled up as far as bevel grinding goes, I also use a sheet of 100 micron lapping film on a very slightly curved substrate for taking care of the backs of chisels.

For honing, the system I recommend is scary sharp with a Richard Kell No.3 Mk.2 guide and two or three shopmade wedges. It is simple, clean, efficient and will allow you to hone just about anything from 1/4" to 2-5/8" including skews and cambers, consistently and accurately. The only exceptions being the really chunky blades of mortice chisels.

I'll pop a set of the scary sharp instructions up on the blog as a downloadable pdf. I think they are pretty comprehensive but if you have any questions just drop me a message.

 

[woodbloke]

I recommend is scary sharp with a Richard Kell No.3 Mk.2 guide and two or three shopmade wedges. It is simple, clean, efficient and will allow you to hone just about anything from 1/4" to 2-5/8" including skews and cambers, consistently and accurately. The only exceptions being the really chunky blades of mortice chisels.

...and that's the honing guide I'm going to use. Matthew is spot on...it will do everything (even cambered blades, once you know how :wink: ) and I agree the only thing it won't hold are my LN mortise chisels. I've yet to play around with spokeshave blades but they're awkward little sods to hold :evil: no matter what system you use - Rob

 

[johnjin]

I think the first thing for you to do is to get the backs flat and a high polish on the last 20 m/m or so of the blade. With out getting the backs good you will never get a sharp chisel. After this then any of the suggestions above will be good.

John

 

[devonwoody]

For me its four grades of wet and dry stuck down on an old glass plate.

I do have a problem with my chisels, when I take them out of their box I sometimes tickle my other hand unintentionally and I think perhaps I shouldn't have them so sharp.

 

[stuartpaul]

Thanks for all the useful advice.

I think I'll probably invest in the scary sharp system and then just spend time 'playing' with it.

A final question though. I understand the grinding and honing bit but is there any magic way of determing when you need to regrind? Does it wait until the edge is damaged or what?

Thanks

Stuart

 

[woodbloke]

A final question though. I understand the grinding and honing bit but is there any magic way of determing when you need to regrind? Does it wait until the edge is damaged or what?

Thanks

Stuart

The blade ought to be reground when the honed bevel gets too wide to comfortably hone an edge. Say for arguements sake it got to 2mm wide, it would then be time to regrind the primary bevel and thus reduce the honed bevel to no more that the thickness of a hair...don't remove it completely as you'll then be left with a very rough edge straight from the Tormek - Rob

 

[wizer]

the roller is always rubbing on, and therefore wearing away the honing medium whatever you use, be it a diamond stone or soft waterstones :shock:

Is that right? I'm sure I've read evidence the contrary. It seems far fetched to me. If it is wearing away it's tiny amounts over a lengthy period. So as not to be a concern.

 

[woodbloke]

the roller is always rubbing on, and therefore wearing away the honing medium whatever you use, be it a diamond stone or soft waterstones :shock:

Is that right? I'm sure I've read evidence the contrary. It seems far fetched to me. If it is wearing away it's tiny amounts over a lengthy period. So as not to be a concern.

If you think about it logically, however you slice it, the roller has to be either wearing itself away and/or wearing the honing medium away at the same time. What's more important though to me is that if a roller is used (of whatever denomination) on a stone, you can only effectively use a small section it...the rest of it is underneath the roller - Rob

 

[Grinding One]

You have a Tormek?Not getting tools sharp enough??What Hospital are you working at??My Tormek will sharpen any tool I put to it,I never wait till the tool is useless to resharpen ,or hone on the other side of the Tormek.You do not carve much with a dull tool....I would tell you to get some better advice on how to use what you have,buying a bunch of systems cuts down on buying wood.

 

[wizer]

You have a Tormek?Not getting tools sharp enough??What Hospital are you working at??My Tormek will sharpen any tool I put to it,I never wait till the tool is useless to resharpen ,or hone on the other side of the Tormek.You do not carve much with a dull tool....I would tell you to get some better advice on how to use what you have,buying a bunch of systems cuts down on buying wood.

I must admit I thought that. To be honest, all you need is a fine diamond stone for quick touch ups. I really don't think you (we) should obsess about sharpness. Tormek plus a few swipes on the fine and/or extra fine stone/abrasive paper would be adequate. In which case I wonder if you might save space an money by going for a couple of diamond stones.

 

[paulm]

I made up a board to hold the dmt stones that has a "run on" area in front of them the same height as the stones, so the veritas jig, or the eclipse, starts on the run on area and allows full use of the length of the stone.

Simple, and providing you make it accurately (or shim it if you don't ) works very well for me.

Cheers, Paul

 

[Smeg]

I must be a bit of a butcher because all i use are a couple of dmt stones and regrind on a disc sander with a suitable jig. The easiest and quickest way i've found to sharpen on a stone is, once you've ground your bevel, hold the stone level in a vice and lay the bevel of your tool flat on the stone then lift the back edge of the bevel slighty off the stone so theres just the very edge in contact. Then move the tool in either a figure of eight or back and forth until you have your edge, then turn your tool over and flat the back. Repeat on finer stones if needed then take any remaining burr off with either a leather or the palm of your hand.
In a workshop where you have deadlines etc you would never get anything done if you had to set up a guide everytime you had a dull chisel.

 

[matthewwh]

Hi Smeg,

Welcome to the forum.

It's a horses for courses thing, cabinetmakers and serious amatuers will be working to a tolerance of around a tenth of a mm, so they need tools that cut with almost no pressure to enable them to achieve those standards. Someone chopping lumps out of studs for cabling will probably be after a more aggressive and less frequent honing regime. Others are in between.

The principles are identical for both, it's just the grades of abrasive and the frequency with which it is done that changes. Whichever way you lean, understanding the seperation between grinding and honing saves a lot of time and improves results dramatically. With a little practice a honing guide can actually save you time as well, 10-15 second to fit the blade correctly, four or five strokes, back to work. Choosing the right specification of tool for the situation is also important.

 

[wizer]

I'm intrigued by this system

Matthew. You're SS Kits include three grades of paper. What instance would I need the other grades?

 

[Smeg]

Hi Matthew, i agree its each to their own. You have to find the balance between getting a chisel sharp enough to use and spending all your time sharpening chisels and not doing any actual work. I do think though its worth investing time in learning to sharpen without guides as when you've learnt the skill its with you forever.

By the way great site Matthew and you my find me purchasing a couple of saws from you in the near future