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weisyboy
30th Apr 2006, 07:42 PM
my chisels are so blunt that they just tear the timbers fibers out.

i would very much apreciate n e info about how to sharpen my chizzels especialy on the angles.

:confused: please help me im desperate!!!!!!!!!!!!!:confused:

johnc
30th Apr 2006, 07:50 PM
Welcome to the forum, 25 degrees is a basic angle for general use, however try the search function it will pull up a plethora of views on sharpening.

John

Auld Bassoon
30th Apr 2006, 07:52 PM
If the chisels are for fine joinery, get some Japanese waterstones (1200, 4000 & 8000, though this last is optional), plus a decent honing guide (the Lee Valley Veritas Mk II is the Bees Knees), and just follow the instructions the LV provide. You'll end up with edges that are surgically (or better) sharp.

If the chisels are more for carpentry, than a white medium to fine wheel on a bench grinder, and again, a bevel guide. Be careful not to overheat the cutting edge though.

Search through this forum, there's a heap on sharpening.

Skew ChiDAMN!!
30th Apr 2006, 08:29 PM
A quick(ish) summary, just to point you in the right direction. (Really, do a search; all of this has already been covered in detail)

I'm assuming that 'cos you've posted this in woodturning that you want to sharpen turning chisels... this is different to sharpening plane blades or other carpentry chisels, so keep that in mind when you do your search. ;)



Firstly, the only tool you really need is a 6" bench-grinder with a white (Aluminium Oxide) wheel. Different turning tools have different angles on the bevels, but for now you can "guesstimate" by loosening the grinder's tool rest (with the grinder switched off!) and placing the chisel in position. Adjust the angle of the tool-rest until the bevel sits fully on the wheel and tighten the rest. (This assumes that the bevel is already at pretty much the right angle.) Turn the grinder on and, holding the tool flat on the rest, quickly touch the tool to the stine. No force is needed, just enough to make sparks. REmove the tool and look at the bevel, you should see the grind-mark in the centre of the bevel, if it's more towards the cutting edge or towards the "bottom" of the bevel you haven't set the angle quite right.

Scrapers can be sharpened by holding 'em flat on the rest, but for spindle/detail & bowl gouges you'll need to learn to "roll" the tool while keeping it flat on the rest. Other tools (and some profiles) have special jigs for easier sharpening, although with practice they can be hand-sharpened too. I do all my tools by hand... I've never bought any jigs.

Only touch the tool to the stone for short periods of time, if the tip turns "blue" you've held it to the stone too long and overheated it. Avoid this. You'll know when the tool is sharp because the bevel is nice & shiny, feeling the other side of the tool you'll notice a burr, and the sparks from grinding are spraying over the top of the tool edge as well as from underneath. Any more than that and you're wasting tool steel, unless you're actually reshaping the tip of the tool. You don't need to get rid of the burr, for scrapers the burr is what actually does the cutting!

The above is good enough to get your tools ready to go back to turning. :) It may sound fairly complex, but it's easy to do... a matter of seconds, really. I recommend that you practise (and practise and practise) on cheap tools until you can do it without thinking. Save your expensive tools until you can sharpen properly. There are jigs, etc. to make it all a lot easier, but once you've mastered the art of sharpening freehand, you won't need them anyway. ;)

For more info on the fine points of sharpening (such as bevel angles, etc), I reallly, really REALLY suggest you search these forums. :D

mic-d
30th Apr 2006, 08:45 PM
Hi, I live just down the road in Kenmore and would be happy to show you how to sharpen plain old chisels and plane blades, but I can't help you with chisels for the lathe tho'
I use 8" slow grinder with a white wheel and 1200 and 6000 waterstones.
Cheers
Michael

felixe
30th Apr 2006, 11:53 PM
If you need to get some sharpening stones, carba tec have the chinese water stones on sale at the moment and they may have a good deal going next week when there sale starts. Get online at the website for the BCC library and search "sharpening" you will find many good books of use - or even easier, take up mic-d's very generous offer.

soundman
1st May 2006, 12:00 AM
Well matey it time to learn to sharpen. I wouldn't last 15 minutes without touching up something on the grinder.
Richard raffins video is realy helpfull on sharpening.
Any of the decent turning texts will be helpfull.
Once you get the hang, skews, scrapers and roughing gouges are a piece of cake. The smaller "fancy" gouges are a bit of a chalenge free hand, lots of people use some form of jig.

cheers

JDarvall
1st May 2006, 12:18 AM
.yep all that.....White wheel , dressing tool, grinder right on edge of table, body up close for as much support as possible,,,,25 degrees (ruffly)

But what I can add to -> 'don't burn steel !'.....<- Its easy to avoid. Just place a finger close to edge while grinding,,,,,you'll naturally stop the blade from burning, cause your fingers will burn first.....and it kinda hurts when your finger tips burn.

Just rip into it and experiment, I'd say with a cheap crap chisel. Ultimately your'll learn a good technique yourself through a lot of practise. Answers should come to you...

CameronPotter
1st May 2006, 10:11 AM
I am a fan of a belt sander (linisher).

It is more efficient and leaves a better edge (in my opinion).

As for not burning the edge, well, I tend to dunk my tools in water as I sharpen them (then dry very carefully once finished). You can see when the tool is heating as the water starts evaporating.

(Oh, and as Apricot said - practice on cheap chisels).

Cam

hingston
3rd May 2006, 05:07 PM
I have just done a tafe woodturning class. I used to strugle. - now it is a lot easier.

The different gouges was the biggest challange. If you can get some one to show you and practice after some instruction a couple of hours, minus an old gouge I can now fingernail girnd a gouge with one face on the bevel freehand

Don 't try and remove too much material at once. I use an old Black and decker 6" grinder, white oxide wheel and a Grinding rest (WMS,Carbatec,Timbercon). When moving the tool to the wheel you should only use light pressure.

A good rule I have found is to apply just enough pressue until you can just start to see sparks comming over the wheel.

Hope this helps

JDarvall
3rd May 2006, 08:39 PM
The different gouges was the biggest challange. If you can get some one to show you and practice after some instruction a couple of hours, minus an old gouge I can now fingernail girnd a gouge with one face on the bevel freehand

If you can grind a fingernail gouge well freehand your doing well. Thats the one have much trouble with.

.


A good rule I have found is to apply just enough pressue until you can just start to see sparks comming over the wheel.

Hope this helps

I agree, when the sparks start coming over, your bevel is meeting the back of the blade.....must stop pretty much straight away...or you start deforming the profile you want, and risk burning that easily heated thin edge you've just ground.....IMO.

Toolin Around
3rd May 2006, 09:45 PM
my chisels are so blunt that they just tear the timbers fibers out.

i would very much apreciate n e info about how to sharpen my chizzels especialy on the angles.

:confused: please help me im desperate!!!!!!!!!!!!!:confused:


If yer coming up to the sunshine coast let me know, bring your grinder, all your chisels and a sack of beer and I'll show you how to sharpen them all.

Jim Carroll
3rd May 2006, 10:25 PM
If you are going to the Brisbane wood show come and see us on Stand 76 and we may be able to help you.

Skew ChiDAMN!!
3rd May 2006, 10:59 PM
If you can grind a fingernail gouge well freehand your doing well. Thats the one have much trouble with.

The trick there is to not use a toolrest on the grinder. The toolrest predefines a plane the tool's shaft will move in, whereas to properly sharpen a fingernail profile it should move in a cone around a vertical axis.

I rest my left index finger on the toolrest (using the rest purely for extra stability... it works just as well without the rest at all, but takes more practive) and rest the tool shaft on my finger, with my left thumb on top. I can then pivot the tool around on my finger without the toolrest forcing the handle "up" as it's swung left/right. It also lets ya know when you're overworking the tool... your finger goes OW! long before the tip starts to blue. ;)

Dang, it only takes 5 seconds to show the difference, but I could probably type another 1,000 words and not really explain it properly. :(

CameronPotter
4th May 2006, 10:43 AM
Well, I certainly DO use the toolrest and mine seem to come out pretty much perfectly - or at least good enough for me.

Mind you, I have a home made tool rest that I adjust to funny angles. I also only use the angle of the tool rest at the start of the cut to give me a reference point, from there it is all pivoting on the edge of the rest.

Cam

Auzzie turner
7th May 2006, 07:50 PM
my chisels are so blunt that they just tear the timbers fibers out.

i would very much apreciate n e info about how to sharpen my chizzels especialy on the angles.

:confused: please help me im desperate!!!!!!!!!!!!!:confused:


I had the same problem as you, untill a couple of weeks ago, I bought a new grinder with an 8 inch grinding wheel, and the same day I bought a grinding jig from Carbatech. They both have helped me tremendously, and I can get the perfect edge every time.

Hope this helped.

Regards......Auzziewoodturner:cool:

JDarvall
7th May 2006, 08:04 PM
The trick there is to not use a toolrest on the grinder. The toolrest predefines a plane the tool's shaft will move in, whereas to properly sharpen a fingernail profile it should move in a cone around a vertical axis.

I rest my left index finger on the toolrest (using the rest purely for extra stability... it works just as well without the rest at all, but takes more practive) and rest the tool shaft on my finger, with my left thumb on top. I can then pivot the tool around on my finger without the toolrest forcing the handle "up" as it's swung left/right. It also lets ya know when you're overworking the tool... your finger goes OW! long before the tip starts to blue. ;)

Dang, it only takes 5 seconds to show the difference, but I could probably type another 1,000 words and not really explain it properly. :(

:D Ta Skew. Sounds like I need more practise. I'm pretty green with lathe work still.

shaft on finger, thumb on top.....I'll try again....

I read somewhere, and it made sense, that its important to get the curves of the fingernail concentric.....thats what I was having trouble with. It seemed hard mantaining this profile. I'd get it sharp alright, but more often than not it looked like a deformed finger, with the tip off to the left or right,

and a dodgy nail seemed to be harder to cut in with too in use....if that makes sence.....

dazzler
7th May 2006, 08:38 PM
hey

cameronpotter gave me a demo using his supartool linishing belt thingamajig and I gotta say it was

Grind-diddly-tastic!:D

Made much more sense than a grinder as you dont have to dress a wheel which deteriorates the minute you start to use it.:mad:

GO SUPATOOL!

Skew ChiDAMN!!
8th May 2006, 12:32 AM
I read somewhere, and it made sense, that its important to get the curves of the fingernail concentric.....thats what I was having trouble with. It seemed hard mantaining this profile. I'd get it sharp alright, but more often than not it looked like a deformed finger, with the tip off to the left or right,

and a dodgy nail seemed to be harder to cut in with too in use....if that makes sence.....

You're right, it's gotta be balanced or it screws things up. Practice makes perfect. :D

Of course, a lot of blokes give up and buy a jig... but no jig I've come across does every type of profile. So you either buy half-a-dozen jigs or buy/build one and end up learning to hand sharpen some of the "harder" profiles anyway. :rolleyes: