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Catches with larger pieces

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Vestas:
I have recently tried to turn larger bowls / platter and when trying to bring the large blank into shape have had a real issue with constant catches.
I’ve tried different tools and raised the rest but it’s been a nightmare ! What am I doing wrong ?

GBF:
The only tool you should use for shaping and creating Bowls is a Bowl Gouge  and a scraper for refining.
You Bowl gouge is probably not profiled properly and if it is you probably dont know how to use it properly.
I sugest you get some tuition from a Profesional Turner.
Plenty of choice on the RPT Website

Regards george

Twisted Trees:
Hard to say exactly, what you are doing wrong is putting the tool in at the wrong angle or too deep.

As a rule it is best to ensure that that the bottom of the bevel is on the timber probably for a couple of revolutions before lifting the handle to tip the cutting edge in, that way if there is a lump in the wood you will know about it before you risk a catch. I think it may be something I do, though it's just a brief moment and I can't actually say if I do it or not...

Another thing is move your feet! aim to stand at the position on the end of the cut you are planning to make, maybe do a practice cut half an inch away from the timber with the lathe off, to check for a clear swing ensure that your feet are not obstructed which may cause your swing to judder at some point and possibly cause a too deep cut to be attempted. Again I am aware of the theory, can't say if I do it or not... though sometimes I do.

Rather than raise the tool rest check your tool is about on the center line lean in and check that the full bevel is resting on the timber with the cutting edge just coming into contact when your tool handle is lifted to the comfortable control position (again with the work not turning)

Make sure that your tool is properly sharpened, blunt tools encourage catches, as to tools with to much of a point where it should be a curve, or even too much of a curve where it is supposed to be a point! to high a wing etc.

Try a piece of white paper on the lathe bed, it highlights the ghost image of any lumps and bumps, more importantly shows the points where your chisel is floating in air and at risk of being pushed in too far next time the bump comes around.

Going to go back to the feet again! sweep the floor, get rid of any shavings / obstructions make sure you are standing in the right place, it is the thing that used to catch me out often bend and twist at the hip to the start of the cut but be in the right place for the end of it.

Hopefully something I have mentioned will help you find your issue, one final thing... what timber are you using? sometimes very dry timber can have hard and soft area's that are just designed to make you have a catch!

John Plater:
This is a difficult one to answer without seeing what the problem is live ! There are the regular generic rules. Check first that tools are sharp, work is securely mounted and the toolrest is set close to the rotating blank to work initially at centre height. Run the lathe at a speed which is comfortable for you. There are also general rules about establishing a cut and following it through. Then it gets tricky. What type of tool is being used ? How is it being presented to the work ? What type of cut is being attempted ? Are you working across the outside of the blank or across its face ? The best advice I can offer is to have someone whose judgement you respect, watch what you are doing so that the problem can be seen, assessed and dealt with. It may be that a relatively small adjustment is all that is needed or maybe its back to basics with a professional tutor.
ATB John

Les Symonds:
I'm with George on this.

Truing up a blank is such a simple, fundamental part of woodturning that you really should not be getting a catch, let alone repeatedly. I really do think that you should get hands-on help from a professional turner/teacher.
I have novice turners performing this aspect of woodturning once or twice a week and never has any one of them had a catch. There are many, many things that you could be doing wrong and the fact that you are unable to identify the problem makes this too vague an issue for anyone to pass meaningful comment on when they are unable to see what it is that you are doing wrongly.

Les

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