So what am I doing wrong?

[Katchin]

pictures say it all, as far as I can tell my chisels are as sharp as I can get them

[Andy Coates]

Actually nothing, John. The wood you're using is spalted beech, which is beech that has suffered fungal attack. When allowed to spalt too far the spalt causes "punky" areas where the integrity of the grain structure has been weakened, and you get these areas of "pull out".

Tools as "sharp as" you "can get them" aren't necessarily sharp enough, so don't always assume that's not the problem.

As for the spalty wood, there are a few things you can do to make a cleaner cut possible.

Soak the bowl in cellulose sealer and allow to dry. You can do a few coats if you wish. Now with a freshly ground tool take a light and continuous (if possible) cut, and you should find the surface is much improved.

Next time try a better piece of wood!

[Katchin]

ok, will try the sealer, thanks. I actually wanted the spalted effect, thats why I was using this wood

[BrianH]

Risking telling Granny how to suck eggs but..............
Whatever you do, John, don't fall into the tempting trap of trying to sand away the problem cos the weaker, softer areas of spalting will disappear quicker than me when the rent's due!!!!
Brian

[Katchin]

good to know, thanks

[woodndesign]

John, I hope from the advice you've been given, you've got a better finish.  One question with regards to your sharpening, is what grind are you using is it standard square grind, (push cuts only) or do you also have one with a long side or fingernail grind, with which you can make finer shear pull cuts with the lower wing, flute just open from the face of the wood, lowering the handle in the cut increases the shear, this can help to over come pull out.         What ever the out come, practise on this one piece will save many more of the same in the future,  will watch for the results of a nicely finished bowl.

David

[Katchin]

Andy, about what you wrote about sharpening. You are correct, after looking at some of the tools that were being used at a demo last night, mine were practically blunt in comparison, with the exception of the scraper and skews.
I bought a new 3/8 bowl gouge last week from Axminster, with the intention of sweeping it back as an alternative to the standard gouge, so far I have half killed it and have managed to gain a terrible edge, I overheated it for one thing. In its current state it is more or less unusable, I think I will have to try to either grind it back to its original angles, or learn how to put the correct angle on it.
I am using the Sorby 447 universal Jig with fingernail profiler, with bad results so far. I am also using the wheel that the grinder came with, maybe this is where my problem lies. The grinder had a thin and a thick wheel, I am using the thicker wheel, grey / white in colour.

Any thoughts anybody?

[woodndesign]

 John,  As you have the 447, have a look at there sharpening video;   http://robertsorby.co.uk/sorbymedia/sharpening1.wmv   http://robertsorby.co.uk/sorbymedia/sharpening2.wmv   The other thing is, was the 3/8 gouge a fingernail profile when brought, as if not the flute maybe wrong for this type of grind.. your grinder sounds to have the right wheels and the white is the one to use, an use the whole face, have you dressed the wheel, taken off the sometimes smooth non cutting surface.. next thing is ask at your Club or show what is going wrong, you need not be embarrassed to ask, we find many want the same answer, when the question is asked..    Hope this is of help.

Thank you to Robert Sorby for their Video.

David

[thebowlerhattedturner]

Hi Katchin,
              I use the 447 system all the time. I also use the grey wheels that came with the grinder. What you need is a gentle touch on the stone, don't press hard or you will draw the temper of the steel. In the past when I ground a chisel to the wrong angle I would stand for ages trying to rectify the problem and get a good grind. That is the worst thing you can do for the steel as it is bound to heat up. Make sure that the wheel is not shiny as this indicates that it is clogged and will not cut efficiently.As David said make sure the profile you are after is suitable for the chisel you have and re-read the 447 instructions and make sure all the settings are correct. In our club we have sharpening evenings where the most experienced members show newcomers to turning how to get an edge on their tools. You haven't done anything that a 1000 others haven't done before you. At least you have recognised the problem instead of trying to plough your way through with blunt tools.
Regards
John

[Katchin]

Thanks. The videos are very informative, i'll check all the measurements in the morning. I will also ask at the club, only problem there is its two weeks before the monthly workshop meeting.

 The chisel I was trying to grind was not a fingernail profile, I thought they could be ground that way though? If not, that would explain a few things 

[Andy Coates]

Hello John,

in truth you can put a long grind on any spindle or bowl gouge, at least any made by one of the main tool makers. I can't speak for the cheap and cheerful non-name tools.

The key is the 2" extension, and the angle you set the adjustable holder at. I haven't used the 447 for a number of years now, so can't remember the setting, but I seem to remember it has graduated settings.

I'll take a few photographs of my spindle and bowl gouges tomorrow and post here. They may give a clue to at least my varient...there are many others.

[Katchin]

cheers, that may help a lot

[Dave Atkinson]

Hello John

You've received lots of good advice.    I would also recommend you buy Keith Rowley's book - Woodturning - A Foundation Course.   I think most woodturners have that on the shelf.

And don't worry - I doubt there is a turner living that hasn't been down the same route as you.  We've all over heated chisels, and wasted steel trying to get an edge (well I did anyway .  One bit of advice i was given when i started was to get a piece of round steel similar in size to your gouge - an old bolt will do and use that to practice your grinding technique.  It's a particularly useful tip if you are grinding freehand.

also keep a pot of water nearby to cool the gouge after a moment or two of sharpening - don't get it too hot and quench it, just use it to take out the heat before it goes blue.

Good luck

Cheers Dave 

[myatt1972]

Thanks for posting your questions John, Im also on the steep learning curve and I'm finding this thread very helpfull.

[Andy Coates]

Sorry for the delay...but here are the pics...

19mm bowl gouge with swept back grind...

And a pair of 3/8 spindle gouges one conventional and one swept back...



The spindle has a flat sweep because that's how I use it, but it could equally have a more rounded edge similar to the bowl gouge.

The trick for me is to concentrate on the nose first - get the nose rounded (not pointed as happens when you concentrate on the sweep), and then sweep back the wings, blending into the nose as you go.

I set the jig to the angle on the nose and the sweep comes naturally. You may have to play about until you get a shape you like and can use, but you will get there.

If you have an un-ground, un-used the fresh tool, try mounting it in the jig with the grinder switched off and set it until you can replicate the shape.

If you want to know the ins and outs of tool geometry you can't do better than Mike Darlows book.

But remember that there are no real "perfect" grinds that suit everybody. Once you find your own you'll know it.