Advice needed - beech bowl finishing

[Stiggy]

Hi guys,

I'm having a go at my first proper bowl in a beautiful piece of steamed beech, using my newly ground bowl gouge (thanks Bob!).

The gouge is being kept sharp, my cuts are slicing, i'm getting really fine shavings but I can't seem to get rid of some areas of end grain 'roughage'.

I have noticed that when I turn the piece by hand the motor lifts ever so slightly once a revolution, which makes me want to think the main drive shaft coming out of the motor is slightly warped?

My question is - would this explain the rough bits I can't seem to touch?

I've put photos below.

This is the face grain, sanded to 120;

This is my end grain, made more obvious for my phone by sanding to 240;

 

[Spindle]

Hi

That's not at all bad - however there is some end grain tear out which suggests either tool not sharp or too heavy a cut.

When you say the motor is out of round are you referring to the lathe spindle? if so I find this confusing as once the work is turned it should be concentric unless it has been re-chucked.

Regards Mick

 

[duncanh]

I suspect that it's just what you would expect with end grain. To determine if it's the grain or the issue with the lathe loosen the chuck jaws (assuming that's what you're using to hold the wood), rotate the piece about 90 degrees and turn again. If the roughness is in the same place then it's just the grain. If it's turned the same 90 degrees then it's your drive shaft/bearings.

 

[Random Orbital Bob]

fraid its nowt to do with your motor Stiggy....nice try, I like that one

End grain tear out is a common problem. Have you tried sheer scraping like I showed you at the weekend? Turn the gouge flute into the work and bring the lower wing gently into contact with the work. You get an even better finish if you have the wing at an acute angle also. That should help.

The "proper" way is to sweep round the curve keeping the bevel rubbing at all times and adjusting the gouge with your right arm as you sweep so it keeps cutting. You should always touch up the edge before you do the finishing cuts because it will cut cleaner when sharp.

Worse case, the pick out will sand away with the appropriately rough grit (80 maybe)

 

[Random Orbital Bob]

Another method is to sheer scrape with a round nosed scraper which you can also hold at 45 degrees to improve the fine-ness of the cut. That might save you a grit or two of sandpaper.

 

[Stiggy]

Thanks guys, yes I'm using the sheer scraping action with the bottom edge of the flute angled down slightly so to slice the grain.

I'll have another go at it tomorrow as I am a little frustrated right now - best to step away.

If I can't get those areas smooth, I'll try Duncan's advice and turn it 90 degrees.

Failing that I'll sand it with a brick...

:twisted:

 

[Spindle]

Hi

An aggressive cut with the bowl gouge can have effects far deeper than the surface - look at your whole technique rather than just you finishing cuts

Regards Mick

 

[Stiggy]

Hi Mick, thanks for the positive comment before by the way!

I think if anything I'm cutting too lightly, but you're right - I need to make sure I learn proper technique.

I'm going to go along to a club near me at the beginning of next month, so will try to get some advice there.

 

[CHJ]

What is your intended finish, Sanding sealer or food safe oil? either way try soaking the torn grain area in it and leave it a few minutes to swell and support the fibres, sheer cutting with a sharp tool will now cut cleaner without pulling the fibres.

Next time do this for the last few cuts as soon as you see any occurrence and reduce the risk of pulling the fibres.


(think of a wet soaped shave as opposed to trying to dry shave)

 

[Stiggy]

...and that's another thing...

...I have wax 22, turning oil, tung oil and danish oil...

which one would be better for a bowl used for ornamental purposes?

 

[Spindle]

Hi

If you are taking light cuts then I feel your tools are not a sharp as they need to be.

Regards Mick

 

[CHJ]

...and that's another thing...

...I have wax 22, turning oil, tung oil and danish oil...

which one would be better for a bowl used for ornamental purposes?

Simple oil application will give you a mat to semi-mat finish, be careful where you place it, not on a polished surface without a coaster. Gloss can be achieved with multiple oil coats as long as it's a polymerising oil that forms a hard skin.

Woodwax 22 will require the wood sealing with Cellulose or Acrylic sanding sealer before application to prevent differing wax/solvent penetration into the wood (end/side grain porosity differences) but will then give you a gloss level quite adequate and reasonably long lasting for display purposes if not regularly handled (it will dull with a lot of hand heat, the beeswax content melts in the hand)

 

[Stiggy]

Well, still not made my fingernail gouge sharpening jig, but found that I can sharpen my 6mm gouge with a sweet bevel. I've been practicing for a few days with it and thought I'd revisit the beech bowl.

What a difference! Although I still need to work on the fluidity of my movements, I seem to understand now how to properly ride the bevel!

It's such a comfortable cut, I feel like I've just had a breakthrough. I only did three passes very lightly but see the difference?

 

[AWG]

Hi Stiggy,

Bowl is looking good! Be keen to see your chosen finish. Have you made some different 'swatches' with your wax/oils?

 

[Stiggy]

Hi Stiggy,

Bowl is looking good! Be keen to see your chosen finish. Have you made some different 'swatches' with your wax/oils?

...you know I never even thought of that!

I have some corners I can play about with - thanks for the advice!

The bowl is under the bench again until I can sharpen my bowl gouge properly!

 

[Spindle]

Hi

If you can do that with a 6mm gouge you'll be really pleased with 10mm or 13mm. I wouldn't consider producing a bowl of that size and style with a 6mm gouge.

You need to sort out your sharpening and, based on your photos, you'll fly from there.

Regards Mick

 

[Stiggy]

Hi

If you can do that with a 6mm gouge you'll be really pleased with 10mm or 13mm. I wouldn't consider producing a bowl of that size and style with a 6mm gouge.

You need to sort out your sharpening and, based on your photos, you'll fly from there.

Regards Mick

Thanks Mick - yes indeedy - I'm looking forward to having a razor sharp bowl gouge - frustrating not being able to sharpen properly at the moment, but by the time I have made my fingernail jig I would have had a lot more practice riding bevels.

The other skill I need to practice a lot is how to move the bevel around the curves smoothly, but I guess that will be easier to do with my 3/8" bowl gouge.

 

[Random Orbital Bob]

It will be easier with a more sturdy tool for sure because it will vibrate less. Really a 1/4" (6mm) gouge is for detail work on bowls, cleaning up the transitions from foot to wall, cutting details like small beads etc, that sort of thing. The hogging off and general shaping tends to be done with a 3/8 or 1/2" tool as the more substantial mass helps.

But you will need to learn the art of keeping your tool fairly steady while rotating your body. After a while you'll come to realise that, just like a mechanical router or similar cutting tool, keeping the tip fairly static while your body rotates through an arc will give a more majestic and accurate "fair" curve. Just keep going, you're doing just fine, it'll all come with time.