Sharpening edge damaged chisels

[WoodNoob]

Hi all,

I have a few chisels that need rehabbing, and I understand about flattening the back etc and do ok with sharpening my un-damaged chisels. But I'm wondering what to do about the ones I have that have a few chips on the sharp edge?

I don't have a grinder or anything other than a two-sided oil stone. I could probably spring for a cheap glass lapping plate and some sand paper or diamond paste, but funds are currently limited to peanuts! So anything more heavy duty than that is out for a while.

What are the recommendations, just flatten the back, and then spend a looooooooong time doing the bevel until I've taken of enough to bring the edge back past the damage?

[Chris Adkins]

A quick cheap meathod is to use a piece of plate glass and sandpaper. I am not a big supporter of the scary sharp meathod but this seems like a good option for you as it cost very little. Once you get the chips out you can go back to your stones. Start with around a 280 grit if the chisels are really rough.

[jsiard]

if you have a belt sander you can make quick work of removing enough material to get just past the chips. Its really no different than using a bench grinder, go slow and keep quenching the tip to keep it cool. Once your back to a clean edge go to your paper on glass working through the finer grits then onto your stone for final honing. I used this method a few years ago when I had the majority of my shop in storage prior to a move and it worked quite well, the learning curve is pretty shallow.

[Boatworks Today]

My thought is that if you have the oil stone for maintaining, it may be worth it to drop the chisels off at a sharpening place and have them do it this once.. I've never priced this but would be surprised if it's more than $10 per chisel? Certainly wouldn't hurt to make a few calls

[ChrisG]

Hi woodnoob. Your profile does not say your location. Perhaps there is someone near you who has a grinder or belt sander who can help you regrind your damaged edges. Short of that I'd reccomend coarse sandpaper on granite or glass. You don't need anything fancy for the flat surface. A granite floor tile from one of the big box stores will work. Also if you don't already have one I reccomend picking up an inexpensive (about $15) side clamping (aka eclipse style) honing guide. You can order one from just about anywhere. I believe Sear often stocks them in their stores.

[CessnaPilotBarry]

--- Start Public Service Message ---

If you use any sort of sander to regrind an edge, PLEASE disconnect it from the dust collector first.

--- End Public Service Message ---

[Jim Heinbuch]

To go really inexpensive (cheap) lay your sandpaper on the top of either your tablesaw or jointer. I use 3M spray adhesive and then clean up the mess with turpentine. Then go to your stones. Make sure you clean up any water really, realy, really, well. Water + cast iron = not a good day.

[aengland]

Easy Peasy...

nope, don't do as I have done--spend long periods of grinding away mass amounts of precious metal to work out jagged, chipped edges! No, No, I say: create a micro-bevel. Just increase the grinding angle on your stone so as to work a steeper bevel (but much smaller edge). By making this steeper, you will more quickly fix the edges WITHOUT cutting off that 1/16 to 1/8th of the whole bevel (assuming no power grinder). Thereafter, just work that beefier bevel back done toward the original 20-25*. BTW, if your edges are that badly crumbled, you might consider making 30* your new standard. Thicker bevel angles make for tougher edges.

YMMV

IMO

.02

[nateswoodworks]

The steeper angle makes pairing a lot tougher so it really depends on what you are using the chisels for. I use oilstones and when I get a chip I have a pretty coarse grit sanding belt , guessing 150 or so, and my granite plate. I cut the belt in half and use a clamp to pull it tight down to my plate. I just use that until the nicks are gone and then go to the stones to hone them back to perfection.

[aengland]

Well, sir, mo money will just about fix most anything....but...you've already indicated that's not happening.

Just some notes on sharpening mediums for you, so that you'll have a "tested" opinion (but, still only my opinion) on what works at this coarse grinding level:

First Your best bet for fast, dependable and good scratch patterns for coarse grinding (other than power grinders) are the 120-400 grit water stones. An Arkansas Soft just doesn't cut as quickly as a DMT 325 or the better Shaptons, Sigmas, Choseras, Gesshins, and the King deluxe 300. The DMTs don't cut as fast nor hold up as long as the waterstones.

My India coarse cuts faster than my Ark soft, but I like the sound and feel of the Soft and Washita Ark. stones far better. Norton stones, which can be found used rather cheaply, cut much faster than the Ark stones. The Shapton 120, Sigma 400, Chosera 400, Gesshin 400, and the King deluxe 300 just blow the Nortons away. Of the ones just mentioned, the Gesshin 400 ($75) and Sigma 400 (~$50) work the fastest and best, followed by the King 300 (~$30). A bit slower again is the Shapton 120 ($ ?) and the Chosera 400 ($68). . Be sure to clean the swarf off your Ark or India stones, flushing with Kerosene, WD40, water, or stone oils (light, machine weight). Do this often.And find a coarse DMT to scuff up your Ark stones--this makes them cut faster (but not as finely). For Japanese stones use only water, and flatten them each time before sharpening. King waterstones will supposedly work, but I have no experience with them. BTW, waterstones are much messier than oil stones (but much faster).

Hope this helps. Let us know where you live so some of us can invite you over to help you out. There ought to be someone with a power grinder near enough, and neighborly enough to make this easier. Just remember, high speed grinders are more likely to draw the temper of your steel. Uh, don't ask how I know

Take care,

Arch

Oh, for me, sandpaper worked, too; but not as well as I had hoped. I far happier using stones.

[rodger.]

I use a collection of waterstones and a veritas MKII jig for plane irons and chisels. It works great, and can easily create a microbevel - a must in my opinion. I am a fan of really sharp though, i usually go to about 8000x.

For damaged chisels, it is usually worth your while to find a grinder. You can get a cheap one from HD, or perhaps you can borrow from a buddy. I have removed some very small nicks with the jig and a 200 grit stone, but it took a while.

There was a good article in FWW magazine not too long ago - I'll look though my magazines and let you know what issue. It specifically mentioned grinding damaged chisels and irons without a grinder.

[WoodNoob]

Wow! thanks guys - that's a wealth of knowledge right there in one thread. I'm going to bookmark this and come back to it over and over!

Regarding neighbours; if any of you wanna pop over to Melbourne, Australia with your grinder and stones, I'd be very grateful. Might even give you a beer

(although there possibly is someone I could impose on)

But I definitely think I can stretch the budget to a granite tile from the hardware store and a few sheets of sandpaper. That should keep me going for a little while at least.

Can you flatten oil stones with this method too?

A jig is on the list of must haves shortly.

Thanks again!

[aengland]

Yes, but my old oil stones, highly dished, are taking forever to flatten--IOW, I'm using up quite a bit of sandpaper w/o much to show for it..

[ChrisG]

Can you flatten oil stones with this method too?

Yes and no. Oil stons will chew up regular sandpaper almost immeadiatly, before any flattening actually happens. A zirconium sanding belt, cut to length and glued to the granite, on the other hand will do the job. If they are really dished it will still take a while though.

[over40pirate]

I made a jig for my belt sander to do a rough grind.

[Jodavis]

i use the dmt extra extra coarse for rehabing blades it removes material very very fast then to to and extra coarse then to my norton 4000/8000 and im razor sharp

[tim0625]

I am a minor league Neanderthal if that! So far, until I know better what I'm doing, I've just used sandpaper and the table saw table. Today I made a big step up....ok little step...I went to the glass place and Scott cut me a piece of 13" x 13" x 1/2 glass from the scrap pile - $10. it should help out until I get better. In my mind, I'll buy sharpening stones one day and buy what will serve me for a long time...just until I know what I want or need, I'm moving slowly with the sandpaper. I'm a hobbiest so it's not a big cost thing now using the sandpaper. So until the money is there or you know what you want, a $10 piece of glass may suffice.

Austrailia??? Dave is in the Blue Mountains. About 663K away from you (412 miles)....and THAT'S as the bird flies!

[Godet]

You can flatten water stones on sandpaper using the methods described above. I recommend drawing a grid with a pencil on your stones so you can watch your progress (when the grids are gone, the stone is flat). I usually use 220 wet/dry for dressing the stones...if rub the paper over the edge of your bench, you can curl it a little bit, which will help it stick to the tile/glass/table saw) Curled paper and water usually holds against granite for me. Don't forget to wet your stone and your paper before dressing the stones. Sandpaper is cheap to use once in a while, but think about a diamond plate if you're going to be at this for a while-over the long run, it's probably cheaper. I highly recommend checking out the Lie-Nielsen YouTube channel. They have several very helpful videos on sharpening...and it's free!

[tim0625]

10-4 Godet....I'll check out the videos...thanks