I need opinions, not a perfect answer, as I realize it all depends on the steel and all sorts of other factors.
What is the best angle/micro-bevel to grind at for a common chisel only used for paring and never for chopping.
Fifteen to twenty degrees?
Flat or hollow grind for the basic angle?
Relation of the basic flat/hollow grind to the micro-bevel?
My question is related to making a set of reasonably quality steel that seem to hold a good edge when chopping. I forget the name of the chisels.. and I forgot where I put them for the winter. Out of the cold shop during winter. Yes, I believe they came from India? and they were not very expensive. However, I find them much more than ‘junk’.. In fact, they work very well and hold a edge.
I have a very heavy 2 inch wide ‘framing’ chisel, I found at some garage sale, that holds a great edge. It is flat ground without a micro-bevel. I recall that it is flat ground to about 20 degrees? Not sure unless I go looking for it.
I would like to make some sort of a fixture that holds the (modified) chisel set on my Tormek grinder stropping wheel to keep them freshly honed .
Other than my big old 2″ framer? that I use for paring,, I now use my Flexcut carving tools. I believe they are all flat ground at 20 degrees?
I only need, sometimes, a paring chisel of different sizes that are longer than them. I see better with my old eyes a bit away from what I am trying to look at!
Replies
I like about 25 degrees for my paring chisels.
If you have a Tormek, (as do I) there is no need for a micro bevel. In fact, in my opinion, micro bevels in general are over-rated, and are a poor substitute for a proper edge.
Where a chisel was made has nothing to do with anything-- what matters is the edge, how easy it is to replace, and how long it lasts. You choose your own compromise between those factors.
Those of us who have Tormeks have it easy. I keep mine set up, and touch up takes less than two minutes, and a full re-grind takes less than four or five minutes. The biggest thing a Tormek gives us is (again in my opinion) the ability to properly sharpen an edge without OVER sharpening it-- and it's all the over sharpening that results in people spending so darn much time on it.
Raise the burr, flip the burr, polish it off, done.
Good luck!
Jammer,
We all develop our methods; no need though to dismiss practices not our own if successfully employed by others. However, I'll have a go at dismissing your anti-microbevel thang. :-)
The Tormek for an intial grind. Just so. It is slow but safe and gives a fine finish to the edge, as well as a little hollow. However, after the intial grind one can put the Tormek away for many months, if.....
a microbevel is used - an automatic one from further sharpening that hollow grind on a flat surface, or a microbevel from tipping a sharpening guide up a degree or two. Then there are advantages....
A 25 degree grind (that safe compromise you mentioned) might become 26 degrees, which is an insignificant change in terms of pushing the chisel and the results it gives. But it is so much quicker to renew a microbevel with a few (unguided) strops on the rouge&oil-impregnated leather. Why get out the Tormek or even a guide every time the edge needs attention?
When there is a need for more than a stropping, why grind off all the steel across a whole main bevel when a tiny bit at the edge is enough if a microbevel is used?
That microbevel may or may not add a bit of strength to the edge. Frankly it doesn't matter much with a paring chisel made of fine grained hard-but-flexible (to a degree) steel such as A2 or similar. The microbevel advantage offers, primarily, that ability to rapidly remake the sharp edge with a minimum of equipment, effort, fuss and time.
***
Pointier bevels can sometimes be useful. I have a couple of fine-bladed straight-edged carving chisels which I keep at 20 degree pointiness. These do slice very finely in the nasty woods (often across a'kard grain or end grain in joints) and it is worth the risk of such a fine steel edge crumbling from too much push (or more likely a twist) of the chisel by me, the cack-hand. So far I have only destroyed one edge requiring a regrind (on the Tormek).
25 degrees for all other "pushers"; and even for those chisels that get lightly donked with the small ekki doinker (not the big mallet, though but). I just have to be careful to resist the temptation to use the chisel tip as a spade, lever or scraper.
Lataxe
Why get out the Tormek or even a guide every time the edge needs attention?
Because I don't "get out the Tormek"-- it lives there, and is sitting there, all plugged in, like a friendly, full coffee pot. No guide, just that big, leather wheel, which is also all ready.
Turn it on, strop, done. I'll be working, with a freshly honed chisel, while you're still hunting for your strap. :)
Will, last year I bought a set of three Sorby bench chisels. They came with a 25 degree bevel, which is fairly typical for chisels. I honed them at that angle and went to do some paring work. The edge folded immediately. I use my bench chisels for paring and trimming more than anything else. I was very disappointed and contacted the seller, The Best Things, as well as Sorby. They told me, if I had bought the large set, they would have come with sharpening instructions and that the chisels needed a secondary bevel, not a micro bevel, of 30 for softwoods and 35 for hardwoods.
I followed their directions and the difference was night and day. I was experiencing edge fold with other chisels I own, Marples to unknown vintage ones. Once I put the 35 secondary bevel on them, the edge lasts forever. I don't use micro bevels on chisels, just on my best smoothing plane. I prefer to strop my edge on leather with a metal polish which allows me to bring the edge back a few times before going back to the stones.
In talking with the owner of The Best Things, he didn't know of any chisels that would hold an edge at low angles. He suggested Blue Spruce chisels as being some of the best but I'm not going to spend that kind of money. Strange that my Stanley low angle block plane blades hold a 22 degree bevel well. I watch Ebay for a certain old brand but I'm not telling the name, don't need more competition.
I used to hollow grind blades and chisels back in the old days, before we had good stones available. I would have 50 chisels today but I ground quite a few to the stub over the years, same with plane blades. I don't grind anything unless I have to, anymore. I don't know if a 30-35 degree micro bevel will give the chisel edges durability. The secondary bevel I now use has solved my edge retention and is easy to re-hone. Can't say I notice any difference between a flat stoning and hollow grinding. The Tormek is much less aggressive than a standard grinder, if I had one, I'd use it but sparingly.
To me, a micro-bevel is essentially the same as a secondary bevel. Micro does imply tiny, but I think they're the same thing. What do you think?
H,
You may find that a folding edge of a chisel or blade sharpened very pointy is likely to occur in those steels that are relatively soft. Modern Sorby steel is notorious for being soft. My blue-handled Marples are similar and (like your chisels) benefit from a 30 degree main bevel and a steeper secondary bevel (still a microbevel on mine) of a few more degrees. However, they may be wapped with the mallet and do not crumble. Soft is OK for the right tasks.
I have some Sprucers which actually came ground to 30 degrees main bevel. That was a recent change from Mr Jeske's initial offerings at 25 degrees. He had a complaint or two about crumbling (not folding) edges so increased the grind to 30 degrees. (The blades are very fine-grain A2 steel - hard but not enough to be brittle in my experience).
I put back a 25 degree main bevel and a 2 degree microbevel on the Sprucers, as I am gentle with them - they are used only to fare the dovetails and other joints. I have no problem with a crumbling edge, which is only likely to arise, I feel, if a chap levers chips out with the tip or otherwise "digs" with it.
I have some very cheap carving chisels which are probably from Eastern Europe or maybe China. They have very hard steel which will form a very sharp edge indeed but are prone to crumble if one puts significant pressure on them. They are said (by the importer) to be deliberately made like that as they are intended for carving softer woods, which enjoy ulta-sharp in their squishy fibres for a clean cut; but don't fight back. They are no good for carving oak, however - even at 25 +2/3 degree microbevel. Soon there is ragged-edge or even a missing chunk.
I am slowly learning that different cutting jobs (and different timbers) need different steels and different edge profiles. Also, some lads pare gently whilst others are quite vigorous-like. Me, I'm a big softy and ever so nice to my tools. :-)
Lataxe
'Ello ducky,
Different sets of chisels, with different steels, and different bevel angles, and 2degrees on this microbevel, and one and ahalf degrees on that; this set for this timber, those tools for that -and yet they still get dull, don't they?
Me, I've allus been limited to those tools I need (not those the timber needs- let the bloody timbers get there own bloomin' steel, if they're that finicky) and can afford, (not being subsidized by the State;-)) and so use them as required by the exigencies of the moment. Yes, sometimes I lever them chips out'n a mortise, and yes, dangit, the edges give way--some roll, some crumble, some just get dull after a while. I re sharpen when that happens, and yet...it is slowly dawning on me, as I get older, and my ambition lessens...the less work I do with the things, the longer they seem to stay sharp! Could there be, do you think, some sort of inverse connexion between these two circumstances? Gotta do more research (the slower I work, the more data I have!), or maybe FWW can do an in depth article-- " Shop Secrets to Make Your Edges Last Longer- does a 2* microbevel Stay Sharper Stored in Canvas, Leather, or Cut-Pile Velvet? "
Ray, who just sees lint when navel-gazing
Ray of light in a dark world of mysteefications,
The answer is....... crushed velvet. Mind, it must be crushed the propah way, by being sewn into the seat of leisure pants worn by a large yet muscular ladee, such as Fatima Whitbread. (Otherwise the fibres are not optimally crushed and any edge cosseted by them goes awry, especially if required to cut the whirlgigs on a scuttle-drape).
The pants must be sat in for only 16.4 minutes, on a leather stool of exactly 1.35 square feet. There should be no undue wrigglin' by the ladee.
Lataxe, purveyor of arcane processes found in various dreems (I recommend either a slice of the quiche for supper; or switching off the dust sucker when sawing certain exotic timbers).
Lataxe,
Mmmm, Whitbread, good ale....
Er, what was that other stuff you were saying?
Ray
Will,
My dedicated paring chisels reserved for fine work are sharpened with a flat 20-degree bevel and a microbevel of about 2 -degrees. I have not yet had any issues with the edges folding over, though they don't see a lot of use.
15* flat grind or hollow ground on the largest diameter wheel you can find.
No microbevel.
Microbeveling defeats the purpose of a low-angled paring chisel. Edge longevity is something you need out of a bench firmer used to chop dovetails or for light mortising work. What you need during paring is blistering sharpness and ease of entry. If you have to hone more frequently then so be it.
The justifications of those that have so overspent on one of those Tormek grinders is some of the most fascinating of all woodworking reading.
My old $50 Delta high speed grinder has kept my edge tools shaving sharp for 25 years. As to the paring chisel, I like a 15 deg +- hollow grind, it may not be correct but none of the wood I have used it on has ever complained…
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