Sharpening of Chisels (again!)

[grumpy6165]

I work in a school with a mixture of about 20 bevel and mortise chisels. This require sharpening every couple of weeks. As the there is little chance of purchasing a Tormek I have to do them by hand. I have looked at cheap sharpening systems such as those sold by Draper and Lidl and these all come with poor reviews.

I have at present a Stanley Honing Set and a range of different grit oil stones. Although its slow the end results seem satisfactory.

Would it be worthwhile purchasing a Veritas MkII Honing System to get a better quality finish.

I have also been recommended to use a diamond whetstone. Does this make a significant difference?

Thanks for your help!

 

[nev]

I would have thought it essential that as part of the education of using a chisel, keeping it sharp is lesson no.1.
Have your students give the chisel a few swipes on the stone using a honing guide if need be at the end of each use.
That way they should stay sharp, save you time and educate all at the same time.

 

[custard]

The only benefit of a Tormek might be that it's permissible for the pupils to use. The big problem is that it is so S-L-O-W, especially when you factor in the frequent need for stone grading/dressing.

IMO you should cross the Tormek off your dream list!

A cheap power grinder with a replacement wheel and a better shop made tool rest might be useful. Alternatively you could use some 120/150 grit paper (maybe glued to MDF or trapped down at each end by a simple jig) to speed things up. A Veritas jig is a nice tool, but again it's a bit fiddly and therefore too slow for your, effectively commercial, purposes. The Eclipse style honing guide with a simple jig for setting the chisel extension/angle is probably the fastest and cheapest solution if you don't want to hand sharpen.

Good luck!

 

[ED65]

Would it be worthwhile purchasing a Veritas MkII Honing System to get a better quality finish.

My 2p: absolutely not.

Presumably the school has a tight budget, so the Veritas I don't think represents good value to you (I don't think it's good value to anyone frankly but that's a chat for another day LOL) and instead you could make a simple honing guide in 10-15 minutes that works just as well but costs pennies or nothing.

I have also been recommended to use a diamond whetstone. Does this make a significant difference?

Even as a fan of diamond plates I don't think so.

Diamond plates can be great and they are probably the fastest honing surface if you put a stopwatch on it, but just for regular honing duties (not a full-on sharpen of something blunt as a butter knife) they're not really that much faster than oilstones. I regularly switch from one system to the other as the mood strikes me and I can turn a burr in nearly the same time on the slowest and the fastest honing surfaces I use.

Your interval between sharpenings is quite long, would you think it might be feasible to do less sharpening but more often? You'd probably have a net savings in time even with doing upkeep more often if you switch to stropping for most of it, that way you might only need to hone proper a few times a year.

Stropping is the #1 way to keep edges sharp if done regularly and often, 30 seconds is the max it should take if the interval between honings isn't left too long. And the great thing about the speed and ease of stropping is that you're far less tempted to leave off doing it just a little bit longer because there's so little faff.

 

[woodbrains]

Hello,

Stropping is a waste of time with chisels that are used by (many) kids! A craftsman will keep the edges as good as he can whilst working, and might refresh the edge with a strop or a light hone when needed. Kids will bugger the edges before they realise they are dull and if they are anything like the kids in my school, will bugger them just for the hell of it, or because they are just fiddlers and will not leave things alone. If you have too many chisels to keep serviceable with oilstones, a dry grinder is the best way, and perhaps think about a jig for that, if you can't freehand grind easily. This is what I do in my school, sans jig, I just freehand. I do like an eclipse honing guide for honing on oilstones though freehand there too, it just depends on my mood and how much of a hone is needed.

Mike.

 

[D_W]

Dry grinder, coarse wheel (cheap is fine), cheap diamond T dresser.

I have no clue whether or not kids could get themselves injured with that, but it shouldn't matter. You can do the grinding and make the grinder off limits.

The tormek is an accurate machine, and it's well made and reliable. It has no virtue beyond that. I've owned a knock-off and the real supergrind and tried to make use of one, but in truth, it's slower than hand grinding on a crystolon stone. I just have no clue what it's good for.

 

[MusicMan]

The feature of the Tormek that I find the most useful is the planer blade grinding attachment. It has saved me money over buying disposable blades, and the planer (almost!) always has nice sharp blades and produces an excellent finish. This one is really hard to do freehand or even with a hand jig. It is slow if you don't do it often enough!

I don't usually bother using it for plane blades or chisels unless the main bevel needs redoing.

Keith

 

[woodbrains]

Hello,

TBH the kids should go no where near the dry grinder. I'm sure the OP knows this, but for the benefit of those not familiar with school H&S.

If the OP needs some help with tool prep, then there should be some budget set aside for equipment of some sort. I know school budgets are tight, but then H&S needs to be taken seriously. By the time a dry grinder is hard wired, put on a pedestal, equipped with a NVR and e stop switches with the associated certification, perhaps a Tormek is reasonable, cost wise. Otherwise, just beef up and use Norton oilstones and an Eclipse honing guide! I have done, and with more than 20 BE chisels, block planes, mortice chisels, carving gouges..... Next term we are getting a new workshop, hurray.

Mike.

 

[D_W]

Does this wood shop have a belt sander?

 

[Trafalgar]

A honing jig and a coarse Norton Crystolon stone (or a few of these) are all you need for rough grinds in that sort of school environment. Tormeks are about as effete as it gets and a regular speed dry grinders, too much. The in-between solutions aren't that great. Do it by hand.

 

[Jacob]

A honing jig will make the job much much slower - it's just a crack-pot fashion item for timid beginner woodworkers.
If you have a lot to do then there is no realistic alternative to normal freehand sharpening - as practiced successfully for thousands of years by millions of woodworkers at all levels of skills, with no problem. Quicker, cheaper, easier etc. And instead of "sharpening every couple of weeks" you do it frequently as necessary, and teach the users how to do it for themselves. Simple sharpening is an integral part of using edge tools and shouldn't be avoided!

PS in a school you will only need one fairly fine grade of oil stone for all normal purposes. Keep it simple.

 

[MrTeroo]

If you choose to do them by hand, Paul Sellers ha just released a new video on his Woodworking Masterclasses website, showing how to make the three plate holder he uses. You need to sign up for a free membership to view it.

https://woodworkingmasterclasses.com/2017/06/sharpening-plate-holder/

Ultex diamond plates fom DMT are the most cost efficient option I believe.

 

[LuptonM]

Hand cranked grinder?

 

[Random Orbital Bob]

Well that's definitive then, only one obvious way forward there so pick the bones out of that lot and....best of luck

 

[bugbear]

Are the pupils expected to (try to) sharpen the chisels themselves?
If so, what is the age of the pupils?

BugBear

 

[Jacob]

Are the pupils expected to (try to) sharpen the chisels themselves?
If so, what is the age of the pupils?

BugBear

We did it in school age 11. It's easy the traditional way - any fool can do it after a few minutes of explanation.

 

[beech1948]

Me too...in school aged 11.

The teacher used to quickly scan all the benches for tools which needed sharpening, grab those and replace with a few spares. Then groups of 6 pupils were indoctrinated into hand sharpening for 15 mins, sent back to their benches and the next group taught to sharpen freehand.

 

[Trafalgar]

A honing jig will make the job much much slower - it's just a crack-pot fashion item for timid beginner woodworkers.
If you have a lot to do then there is no realistic alternative to normal freehand sharpening - as practiced successfully for thousands of years by millions of woodworkers at all levels of skills, with no problem. Quicker, cheaper, easier etc. And instead of "sharpening every couple of weeks" you do it frequently as necessary, and teach the users how to do it for themselves. Simple sharpening is an integral part of using edge tools and shouldn't be avoided!

PS in a school you will only need one fairly fine grade of oil stone for all normal purposes. Keep it simple.

A honing jig and coarse stone in this instance is in lieu of a grinder. It's no different than using a grinder tool rest. For final honing, a freehand method should be taught at some point in the curriculum (early), as well as dry grinding on a full speed grinder (later). For keeping an inventory of chisels intact, without turning them into nubs each semester, it seems like a reasonable course of action. Learning how to grind dry on a high speed machine would be a bit of a Pyrrhic victory if there are no chisels left for the rest of the curriculum, or the ones that were left had their temper drawn an inch and a half up the tool. Weed the clumsy oafs out before teaching how to grind.

 

[ED65]

Stropping is a waste of time with chisels that are used by (many) kids!

The sharpening interval reported by the OP suggests that stropping might be very viable.

Obviously stropping only works on edges that have minimal wear and weeks from sharpen to sharpen does seem to suggest that the chisels don't get heavy use or much abuse.

 

[woodbrains]

Does this wood shop have a belt sander?

Hello,

I guess this question is aimed at me...new workshop next term.?

Yes, there will be a vertical belt sander (band facer). I'm guessing you are reasoning if there is a belt sander used by the pupils then they should also use a dry grinder. Well not exactly, the comparison of the 2 machines is not exactly the same.

If the powers that be are true to their word, we will be getting a horizontal grinder for tool prep in the new building, nice...

If the suggestion is to the OP for using the belt sander as a grinder......a sure fire way to start a fire!

Mike.