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jimran
2nd March 2007, 08:06 AM
HELP!
I am a beginning turner and am having a devil of a time avoiding catches when attempting to turn the inside of a small bowl (about 4" inside diameter). The blank is a redwood burl and has a wavy, natural lip. I am wondering if my tool rest height is wrong. I can do all right on the outside but when I try to turn the inside - Bam - the dreaded catch. I have the tool rest set at right angles to the lip of the vessel so have about an inch and a half of overhang on the tool. I will switch to the rest parallel to the vessel if I ever get it deep enough to do so. Any and all advice is more than welcome

lubbing5cherubs
2nd March 2007, 08:44 AM
Gidday mate, I am only learning myself so I can't help you out much. But I just wanted to say welcome to the board. SOmeone will be out of bed shortly will be able to help you
Toni

TTIT
2nd March 2007, 08:55 AM
Welcome to the forum Jim. Need to know what type of chisel you are using??? Avoiding the catches will depend on how you are 'presenting' the tool to the wood - ie: angles, height etc which varies with each tool.

Cliff Rogers
2nd March 2007, 09:46 AM
:repost:

Lessons and see if you can find a club near you or some forum members who are turners within range of your place.

While you are learning, you will learn heaps faster hands one with an experienced turner. (Or even a novice who has already had some lessons & made a few things already)

Next best is videos but they are apoor second place 'cos you can't ask questions.

WillyInBris
2nd March 2007, 11:54 AM
Hi Jimran,

I would have to agree with cliff, try to find a club in your area, I have now been going to lessons for the past month every Sunday and I have been learning so much, correct presentation of tools and accuracy, as well as some social fun as well.

All I have been working on is spindles and this week I start to make my own chisel handles as well as a mallet.
Then after that on to bowls, I am looking forward to that.

I have to thank everyone on this forum for pointing me in the right direction to start with.

Willy

Rookie
2nd March 2007, 12:19 PM
Information as listed by the others will help, on the chisel you're using etc. But interested that you are using a burl as one of your first pieces. I am a beginner as well and I know that burls are prone to catches more then anything.

Also, the four most useful tips I have received from the folks here are
1. Cut with the edge of the gouge, not the point.
2. Make sure the bevel is rubbing against the work.
3. Make sure the bevel is rubbing against the work.
4. Make sure the bevel is rubbing against the work.

Especially inside a bowl, you are sure to catch if don't have that bevel right.

And as Cliff mentioned, lessons. Joining a club that has experienced turners who are happy to pass on info, is the best thing I ever did and the thing that progressed my skills heaps faster than trial and error at home.

joe greiner
2nd March 2007, 02:08 PM
Tool rest perpendicular to the lathe axis is preferred for inside work. A lot depends on the tool you're using, but rubbing the bevel reduces likelihood of a catch. With a scraper or boring bar, the wall cut should be above the "equator" so that the wood moves away from the cutter; for the bottom, below the equator. You can accomplish this by rolling the tool so that the effective equator is at an angle. By all means, visit and/or join a local woodturning club. Last I checked there were 16 AAW chapters in CA. Go to www.woodturner.org, and boink the menu item for AAW chapters. You'll find that woodturners are some of the friendliest folks you'll ever meet.

Joe

Cliff Rogers
2nd March 2007, 03:20 PM
...
1. Cut with the edge of the gouge, not the point.
2. Make sure the bevel is rubbing against the work
....
Arh but.... Jimran may be using a scraper. :wink:

With hands on tuition I had my teenage nephew doing fine shear scrapes with a bowl gouge on the inside of the bowl on his first bowl & he didn't have the bevel rubbing.
I could never find the words how to describe that in a book, I'd have to demo it but once you are shown & try it, it is easy. :2tsup:

Frank&Earnest
2nd March 2007, 06:18 PM
As a rookie myself, I have experienced that just recently. As I was in a turning class, the instructor immediately showed me what I was doing wrong. Nothing to do with the bevel rubbing (it would be damn awkward to keep that angle inside a small bowl anyway, don't you think?)

What I was doing wrong was to cut with the corner of the gouge instead of the point (i.e. the angle with the wood on the horizontal plane was acute instead of close to 90^). Rookie and Cliff, what do you mean with "Cut with the edge of the gouge, not the point" ?:?

Cliff Rogers
2nd March 2007, 06:25 PM
...Rookie and Cliff, what do you mean with "Cut with the edge of the gouge, not the point" ?:?

The sharp edge on the side of the gouge just around a bit from the tip, not the tip unless you have the gouge rolled right over a 90° with the bevel rubbing & the tip going away from you.

I need a picture, I'll find one tomorrow, right now, I'm late. :-

It is much easier hands on than it is to try to describe it. :p

iron bark
2nd March 2007, 07:34 PM
One thing I have learned is that whatever part of the tip you are using to cut, must be supported on the tool rest- ie if you use the edge, then the gouge has to be rolled such that the edge is sitting on the tool rest - also make sure that a corner in particular doesn't inadvertantly touch the work whilst using the inner part of the gouge when you are moving or rolling it - that's just my opinion from self teaching and a little bit of experience - seems to have almost eliminated catches - but then again, a moment's inattention to what I am doing and CATCH

Cheers,

Ned

rsser
2nd March 2007, 07:48 PM
He (she?) is going into a natural edge and that poses its own challenges. Not the best place to start as a turner.

+1 to lessons or demo's from a mate.

Added: OK. If it's gouge, flute facing upwards, line up the bevel on the left side with the direction of travel, handle dropped a bit below horizontal ... then feed it in slow holding the shank firmly on the rest. First you'll hear is ticking as it cuts the high points.

Have you drilled a pilot hole to the intended bottom of the piece? If so, starting turning away the stock from the hole.

BernieP
2nd March 2007, 08:20 PM
G'Day Jimran

Welcome aboard, listen to what they say and you can't go far wrong, if you send a few photos it will help for them to explain.

Cheers
Bernie

jimran
2nd March 2007, 08:50 PM
Thanks to all! I am amazed it has been less than 12 hours since it sent my post and a bunch of replies!
Jimran

hughie
3rd March 2007, 11:02 AM
Jimran, while your looking for a woodys club have alook over these links



http://www.pennstateind.com/library/Mini-bowl-FP001.pdf
http://www.woodturningonline.com/Turning/Turning_articles.html#design
http://www.turningtools.co.uk/wtintro/wtintro.html
http://www.youtube.com/watch?v=UVWrT5LDeuA&mode=related&search=

Cliff Rogers
3rd March 2007, 11:20 AM
I found (stole) a picture & put some arrows on it.

Do NOT use the tip, red arrow.

Use the side, green arrow. (maybe a bit further forward than where the arrow is for a finer cut.)

Frank&Earnest
3rd March 2007, 04:33 PM
Now it makes sense - the problem was in the meaning of tip, point, edge corner. Ned's self-taught wisdom is basically what I have been taught.
I re-stole the picture and added a thick and cross on the relevant areas, whatever their name. Thanks.