Dumb Wood Turning Question

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Okay...now you guys all know I use a lathe a lot, and know how to turn between centers, facing, off-setting the tail stock and cutting threads and all that is good in the metal working world, but how do you keep your hand held turning tools exactly on the centerline?

Every time I use my wood lathe, my tools "catch" the wood and either stop the stupid thing from turning, or gouge the wood. Either way, this jumpy guy, jumps and its not a lot of fun.

Now at work, the tool height is set to withing a few thousands of an inch and is shimmed and adjustable and seldom is changed. At the same time, I never catch the metal with this system, or at least very seldom to I "catch" the metal anyway. So I was thinking about building a carriage system, and an adjustable tool holder that was geared to my shops wood lathes spindle so that for every revolution of the spindle, the carriage would move ahead by a few thousands of an inch. This would give me a consistent chip, and yet also keep the cutting edge of the tool inline with the centerline of the turning. That is the only way I can think of to keep the cutting edges from skews, gouges and whatnot from catching.

So then I began to realize, I am basically going to have to convert my wood lathe into an engine lathe. Something is wrong with this picture because I doubt other wood turners go through all this just to keep your cutting edges from "catching", so my question is...what do you guys do to keep your cutting edges from "catching" the wood?
 
...so my question is...what do you guys do to keep your cutting edges from "catching" the wood?
Practice. ;)

Seriously, I don't think I'd want the tool to be constrained to exactly on the centerline. Even with the same tool (a gouge, for example), there are a number of ways to present the tool to the wood, for different kinds of cuts. Some are on the centerline, and others aren't. (Technically, they are on the centerline, but at a different locations on the cylinder.) The trick is learning how to present the tools. I'd bet 30 minutes to an hour with an experienced turner could point you in the right direction.
 
Travis, try as I might, I still get a catch now and then. Unlike metal, wood changes in density between growth rings. Add to that the ever changing grain structure and catches are bound to happen. Scary sharp tools will help to avoid the quantity of catches and light cuts help, but I don't think they can be eliminated. At least not using a human guided cutting tool. In spite of our best efforts, we cannot maintain a consistent pressure or feed rate. A machine guided cutter doesn't have this limitation, unless it is hand guided.
 
Your machinists mentality might be getting in the way. Shift gears to a state that accepts the natural deviations in wood. Center line, above, below, varies depending on the tool, type of wood, what you want to do, moon phases, etc. Keep at it until you get comfortable.
I'm thinking that you may also be using too slow a speed. Rev up to fastest you believe safe. e.g. don't turn your piece into a flying missile. Then with a light touch, watch the 'shadow' and turn down.
 
Frank hit the nail on the head... so to speak. Your Machinist mentality is getting in the way.

All the rest of the wise comments others have said are true as well...


My S-I-L is a Machinist in the Aerospace industry and his tolerances are so fine that he thinks in giant decimal places as well as expects materials to act and react in specific manners. Wood does as well but with unpredictable variances. :huh: Wood turning is not "Set-up and push the Green button" It envolkes a human touch and this varies with each tool used as well as the posture and size of the turner (fellow holding the tool) We speak of tool rest height being just below center, etc. but in reality the center is determined by the height of the center in relation to the height of the turner, as well as his/her techniques and the presentation to the work. Does the turner crouch over the work or stand back , long or short arms , how do you hold the tool?

A good example of the presentation is the new lathe from oneway that is designed with the sitting person in mind, Although it is not a perfect design it does address the issue.

Raise or lower the tool rest with each different tool and the presentation changes with each different tool. Easiest way to precvent "Catches" is to raise the presentation so that you are cutting before dead center, more aggressive cutting incourages "Catches" and below dead center assures them. Find the happy medium for your posture, size and tool.
 
I would offer this. I quit getting a lot of catches when Bill Grumbine told me ride the bevel. The bevel must touch the wood first then move the tool till it starts cutting. Ride this bevel thru the cut by moving your body. If you are holding and moving the tool with just your hands, yep you are going to get a catch. On a bowl gouge for instance I hold the tool against my body and once I get the bevel rubbing I just move my whole body with the cut. Raffan says the same thing.
 
Bernie has it---the tool must be supported by it's bevel to prevent catches, as least for cutting tools. Scrapers, on the other hand, must be presented at a downward angle, below the centerline in order to avoid catches.

Dan
 
iam new at this my self the man i bought my delta told me to buy the dvd by richard raffan turning wood has been a big help for me
 
The bevel must touch the wood first then move the tool till it starts cutting.

I've read about the 'A-B-C' method.

Anchor - get the tool anchored on the toolrest
Bevel - lift the handle of the tool until the bevel is rubbing on the wood
Cut - lift the handle of the tool and/or rotate the tool until the edge is cutting

Several other things could be contributing to your catches:

Toolrest too far from the work. You should generally have the front of your toolrest as close as possible to the piece you're working on.

Improper presentation of the edge to the work. Regardless of bevel rubbing, if you get the edge of the tool into the wood at a bad angle (especially with the skew) the tool is going to run away from you and/or catch.

Dull tools.

Watching videos helps a lot. Personal instruction is even better.

-Joe
 
here is my suggestion.

When I first started someone (cant remember who) told me to lay aside the skew for a year, or until I was comfortable with all other tools. the skew is most likely, in many turner's opinions (I think), the most temperamental turning tool, which so happens to create the finest cuts once it has been tamed. for now, lay aside the skew and just play with gouges for spindle work.

listen to the other experienced folks in here. Rub the bevel before cutting. Make sure the tool is in solid contact with the toolrest; the edge that you are cutting with is being supported by the toolrest. In other words, dont cut with one side of the gouge while the other side is supported by the tool rest. The image should depict this. dont cut with the gouge where the top arrow indicates, while it is supported by the toolrest with the bottom arrow.

Hope this helped,
Ben
 

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