Thread: sharpening advice

Toni, a million threads on this if you do a search, probably confine your search to the woodturning forum for specific advice on woodturning chisels, srapers, etc.

I believe the basics for this are sharpen on a bench grinder with or without a jig, try to replicate the original sharpening angle and profile for best success (if you don't know what you are doing modifying the shape/grind), don't overheat (blue) the edge - some use white grinding wheels for carbon steel tools to help with cool ginding but I believe HSS tools will require the normal grey SiC whells, try to grind the tool to achieve one bevel rather than a series of bevels, dress the wheel regularly to expose sharp grit which helps with cool grinding.


Good luck...................cheers...................Sean

sean,HSS is best suited to white wheels aka aluminium oxide .

How far away is Winton from Toowoomba. We're planning a sharpening get together there and maybe you could bring the tools. Nothings better than a first hand lesson. If the link below doesn't take you to the thread then look for "So who's interested in a day(s) of sharpening" in the Hand Tools and Machinery sub forum.

http://www.woodworkforums.ubeaut.com...ad.php?t=34496

OK, here's a crash course in sharpening for a lathe...

1. Tool angles:

• Scrapers, 80°
• Bowl gouges, 55°
• Roughing gouges, 45°
• Spindle gouges, 35°
• Skew chisels, 25°
• Parting tools, 25°

These angles aren't gospel, 5° one way or the other is perfectly normal; most people I know (myself included) change these angles to ones that feel more comfortable for them. But so long as your tools are fairly close to the above the bevel angles aren't your problem.

2. Ideally, the bevel should be one smooth face, and not faceted.

3. When freshly sharpened you should be able to feel a fine burr on the top edge. Don't worry about this... in fact scrapers need it to be there to cut properly. (Unless you're doing the last finishing cuts, in which case removing the burr gives a less aggressive cut and a smoother finish.... but I wouldn't worry about that yet if I were you. I wouldn't mention it, except I'm sure someone will bring it up and confuse the issue sooner or later. )

4. If you're using Carbon Steel tools, when you're sharpening keep an eye that the very tip of the cutting edge doesn't get hot enough to turn metallic blue. Once it's blued, it's useless... ya gotta keep grinding until it's removed and you're back to "virgin" steel. So, use a light touch when sharpening and only grind for a few seconds at a time. A bucket of water to keep dipping the tool into for cooling is a good idea too. For HSS tools this isn't a problem, but it's not a good idea to overheat 'em just the same.

5. use a WHITE wheel on the grinder (Aluminium Oxide) and buy a diamond dresser to keep it squared. Grey wheels are too aggressive and will cause you all sorts of problems.

There's more, of course, but the above should be enough to put some life back into your tools. I don't suppose there's any other turners within cooee who could have a look at your tools or show you you how they sharpen?

hey skew and others.....with grinding skew chisels, does the angle and way you sharpen change with different types of skew chisels eg, oval skew, normal skew etc

I use a grinding stone at the moment but will soon be upgrading to a bench grinder soon!!
Sometimes i take my tools to school and use their grinder to give them a touchupwhen the teacher lets me that is!)

Are you using a white wheel in your grinder : these grind cooler and help put a better edge on the tool..

also you could give your tools a bit of a touch up on a grinding stone after a grind to smoothen out any rough patches..
Hope this helps, Dylan

Thanks for the correction Stirlo & Skew


Cheers............Sean

Originally Posted by Toolin Around

How far away is Winton from Toowoomba. ..

1233Kms about 14hrs drive.
http://www.nowwhereroute.com/travelm..._Toowoomba_QLD

Originally Posted by Toolin Around

How far away is Winton from Toowoomba. We're planning a sharpening get together there and maybe you could bring the tools. Nothings better than a first hand lesson. If the link below doesn't take you to the thread then look for "So who's interested in a day(s) of sharpening" in the Hand Tools and Machinery sub forum.

http://www.woodworkforums.ubeaut.com...ad.php?t=34496

Try about 1000km away. I love to get away to do a course. It on the one day to do list
Toni

Originally Posted by lubbing5cherubs

Try about 1000km away. I love to get away to do a course. It on the one day to do list
Toni

It ain't a course, and it'd be worth the drive!

Wish it was down Melbourne way

got my Veritas Mk2 today - looking forward to trying it out.

So, Stuart... did I hear you say you're hosting "Sharpening Down South"?

Originally Posted by ss_11000

hey skew and others.....with grinding skew chisels, does the angle and way you sharpen change with different types of skew chisels eg, oval skew, normal skew etc

Basically, no. Oval skews are a tad harder to sharpen as they tend to roll when sharpening but normally you'd try to hold 'em flat for sharpening in the same way as a std. skew.
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Having said that, there's still a lot of "personal" variations in the way they're sharpened. I know one turner who rolls his oval skew when sharpening, the same as you would for a bowl gouge (except on both sides) because "that's the way he likes it." [shrug] I don't do this, however I do like to have a curved edge on my oval skews instead of the more traditional straight cutting edge. I know I'm not the only one who does this.

I've also shaped one of my skews so that the bevel angle increases towards the pointy end. I use this tool specifically for beaded legs, as it reduces the no. of tools I need for the job.

In other words, once you start customising your tools, all the rules go out the window as you find what works for you. I'm honestly not sure if any of my tools have the same profile now as when I bought 'em.

If I may add to the outstanding advices you already received I would say that you should not hesitate to go often to the grinder even if it is to take away a zillionth of millimetre of metal.
Often I have seen turners, young ones (in terms of experience), to doubt about themselves when they do not perform as they used to, and the reason is only because the gouges are not sharp enough…
Try! It’s worth it <O</O

Thanx skew

Lubbing5cherubs

Let me just add that the advice given is excellent. In particular the comments by La Truciolara say a lot between the lines. In my early turning days I was reluctant to place a chisel on the grinder. I guess I didn’t want to screw up a good tool. Eventually my chisels reached a point where they couldn’t get any worse and I had no alternative.

I was somewhat tentative and opted for jigs. This gave me a perfect angle every time but was time consuming in that the jig had to be set up and often involved several jigs for several chisels. The scrapers were of course the easiest and also generated the confidence to attempt other tools ‘free-hand’.

The medium I have reached is to ‘free-hand’ chisels (for just a few seconds) during work but every so often to set up the jigs and reshape all my chisels more accurately. The ‘free hand’ visits become more frequent with experience, particularly when you remember how easy a piece is to work with a sharp tool. Although rough and ready the result is spectacular, particularly when you know you can fix it up later with a ‘jig regrind’. It’s a confidence thingy!

That zillionth of a millimetre mentioned by La Truciolara is all that is needed to improve work and boost confidence.