Problem with bowl turning

[Haggy]

When bowl turning my aim is to achieve  a perfect finish straight from the gouge.
 I can achieve this on the outside of a bowl with a freshly sharpened gouge and a bevel rubbing push- cut.
When I  remove the waste from the inside in a similar fashion I fail to do this in a single pass -this leaves a ridge between the side wall and and the base of the bowl ( see pic) as the shaft of the gouge hits the bowl rim on the transition from side wall to base . 
My solution is to use a scraper to remove the ridge but this often results in chatter marks or slight tear out, I then have to resort to sanding or removing the chatter marks with a gouge, but I am back to square one!
 I could solve the problem with a shallow curve on the inside of the bowl but it isn't the profile I am after.
Is the solution to grind a double bevel on the bowl gouge to get into tighter curves?
 When wood turners say they can get a perfect finish straight from the gouge is this a myth or something that can be mastered with experience?  I am thinking you can't  clean the inside of a bowl in a single pass like on the outside - unless you have a 'gentle curve'.   Would I be correct in my thinking?
          Thank you.
                        Haggy
   

[The Bowler Hatted Turner]

Haggy without being there with you and watching over your shoulder may I suggest that you look at the grinding angle of your gouge to see if the bevel will rub all the way around your chosen profile, if not you may have to adjust that.

[edbanger]

Hi Haggy

That bowl does not look that deep so you should be able to to make the cut in a single pass and with practice take it to a finish.

You should be looking to slice with the gouge which will give you a better finish. My guess is from the picture you might not be achieving this, your hands look high for the start of the cut, are you cutting with the top half of the blade but just below the tip?

The on / off cutting action should be with the hands / handle away from the body your cutting more and has you bring the cutting edge towards you you are cutting less, well that the way I've been taught and it works for me.  When I start the cut the cutting edge is between 9 & 10 o'clock with the flute of the gouge pointing at around 2 o'clock my hands low and away from me and has I turn-away the inside the hands are slowly raised and pulled towards me, the blade is slightly push into the cut with the right hand but not to hard to make sure that I don't lose the cut. By the time you have reached the centre your hands are at 9 o'clock and the flute would be rolled round to about 3 o'clock taking out the pip in the centre.

My gouge has a grind of 45 degrees if I'm doing deeper bowls say 4" and above I'll use a 60 degree grind gouge.

My guess is there are other ways to get there as we shall see posted, I hope that what I have put reads clearly explaining by type is not one of my strong points  

Ed

[TWiG]

You can also change to a different grind part way through ( 2 chisels ) This is common practice with deeper bowls .  Some have mastered a perfect finish in one pass from a gouge but it is probably with  a lot of practice and experience with a lot of rather boring bowls of perfect wood with shallow profiles .  

[edbanger]

Haggy

Just a thought after seeing BHT comment if you post a link to your video one of the pro's here (not me I'm still learning) might be able to take a look and that tell you what they think.

Ed

[GBF]

You are making life difficult for yourself by creating a bowl where you do not have one sweeping curve throughout the inside of your bowl.
It looks to me like you are making what we call a dog bowl where the sides come down and then you change direction to create a bottom.Try and create a bowl with a simple sweeping curve and you should not be a problem.
Also just grind a small second bevel on your bowl gouge to stop the heel of the bevel bruising the wood.

Regards George

[Haggy]

Thank you  AWGB for giving me something to experiment with, particularly you careful description of what works for you Ed. 
The picture is of an American Woodturner on U tube, but what sparked me off was he was running into the same problems as myself.
From these comments I will conclude it is possible to finish the inside of a bowl with one pass ( thanks BHT)but I need to experiment with bevel angles, possibly grinding a double bevel so I can get round the curve.
If that doesn't work I will try your suggestion TWiG - thanks
The bowl I have just turned hasn't a 'dog bowl' profile and is about  300mmx100mm deep.  I am simply trying to replicate the outside shape. I can post a pic if it would help.  To conclude, I am pleased with the outcome, but not happy with the process.
          Haggy

[Haggy]

Pic of the bowl I have just turned- there is slight tear out on the end grain, I guess it would have helped if I had posted this at the start!
     Haggy

[Bryan Milham]

As George says, try and achieve a sweeping curve. The movement of the gouge through that curve can be eased by an upward sweep of the flute from the start of the cut.

Easier said than explained, but I'll try.

You touch the tip of the tool onto the wood to create a start for your bevel to rub against, you turn the tool so that the flute starts to cut and ease the tool into the wood. At some point not too far into the cut, it will be easier to push down on the handle, bringing the cut upwards slightly, you will need to keep the angle of the flute adjusted at the same time.

Just over the half-way point through the shape of the bowl curve, the tool will cut easier if its guided back down by lifting the handle.

You should finish on the centreline cutting through the center and hence not leaving the little pip.

The curve followed by the tool is sort of a 3D Sine Wave. If you've never cut like that before, don't try it on the final cut, practice it on preceding cuts remembering that you are practicing each cut so that you can make the final cut with confidence.

[Haggy]

Thanks a lot Brian, I think I do understand what you're describing but need to have another go at this to see if this is what I'm doing.   You make it sound straight forward, but I know things are different in practice.  The bevel is ground to 50 degrees on my gouge which is deep fluted, so I am contemplating putting a secondary bevel on the gouge as GBF suggests.
  Many thanks
      Haggy

[GBF]

It would be useful if when members are filling in their profile  they put in the area they live in then when they are having problems a member local to them might suggest getting together and sorting it out.

Regards George

[Les Symonds]

It would be useful if when members are filling in their profile  they put in the area they live in then when they are having problems a member local to them might suggest getting together and sorting it out.

Regards George

George; that is an excellent idea and it would be great to think that some of the more experienced members would be willing to give of their time to help those of us who have struggled through, or are struggling through some of the practicalities. Having said that, I think that I'm a bit out-on-a-limb here in Bala!
Les

[Haggy]

It is a good idea George, although I appreciate the fact woodturners take the trouble to share their knowledge and encourage like they do over the internet.
  Thank you for your concern, when I know something is possible I love the challenge and I will watch closely when I next go to a woodturning demo.
             Regards.  Haggy

[GBF]

When you go to a woodturning Demo ask the demonstrator for help with your problems.

Regards George

[julcle]

Haggy  --  Just put a general location in your profile such as your county, you never know you may get a PM from someone local to you that can help. It happened to me on another forum.  Julian