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Arron
22nd January 2008, 06:31 AM
Hi, I'm relatively new at turning and these are some of the things that I have been wondering about. All of these questions apply to turning between centres (if it makes a difference).

I have been reading a book on turning which seems to imply that every time you make contact between a tool and the workpiece you should first get it resting on bevel, then after a second or two waiting for it to steady, withdraw the tool slightly till it starts cutting. I seem to remember something like that at the course I did too - though it wasnt enforced. Am I interpreting this correctly, and if so, who can say they do this every time - or do most people shortcut?

Second question - I have one of those cheapo Hare and Forbes lathes. The hollow tailstock allows a boring bar to be pushed through. The hole diameter is 10mm (or is it 3/8inch). What do you do when you want a hole of smaller diameter in the workpiece? I tried pushing a 7 mm auger through and ended up with hole that started offcentre and went crooked from there, which didnt surprise me.

Third question - my reading and limited experience implies that a skew chisel is most effectively used when it is at making contact with the workpiece almost at the top surface - say at a point 10-20 degrees from vertical. Is this true? If so, why does my lathe have such a short tool rest post. It doesnt seem to allow the tool rest to be raised above the mid point. What do others do about this? Obviously moving the toolrest further from the workpiece will help but that seems to violate another safety cannon.

Final question - I should know this from the course, but I always end up wondering. If using a roughing gouge for roughing, what part of the tip should really be doing the cutting. Is it the side or the bottom corner ?

many thanks for reading this far.
Arron

rsser
22nd January 2008, 06:43 AM
1. It's a useful habit for beginners but yes, after a while you know where to start your cut straight off.

2. Same here. Options: get a 3/8 auger; get a copper sleeve; live with it. There are techniques to minimise wander as well; do a google.

3. You're talking about planing cuts and no it's not essential to do it this way.

4. Use any part of the edge to even out the wear. The straighter part of the edge is useful to produce an even cut obviously. Use the tip to get into corners.

Hope this helps.

RETIRED
22nd January 2008, 07:57 AM
On long hole boring through the tailstock the hole size through the tailstock is immaterial.

You use a special bored through revolving ring centre that is drilled the diam of the drill. This keeps the auger (in most cases, a special tool) centred but in some timbers it will wander a bit.

See here: http://www.cws.au.com/cgi/index.cgi/shopfront/view_by_category?category_id=1107145003

Sawdust Maker
22nd January 2008, 01:21 PM
Arron
Did you pick this lathe up on Saturday?

rsser
22nd January 2008, 02:44 PM
A dead hollow cup centre for the tailstock is also an option. Cheap if you only need it for one or two jobs.

If you've shaped with the other end held in a chuck and a live centre at the tailstock, just be sure you slip the dead centre in and bring it up to mark the end grain for locating purposes in case you have to demount the piece.

Or else you can do trial and error; no drama if you've got enough stock diam to accommodate a slightly off-centre start to the drilling and for wander.

Arron
22nd January 2008, 06:04 PM
Arron
Did you pick this lathe up on Saturday?

yes, that was you was it ?

Arron

Sawdust Maker
22nd January 2008, 07:55 PM
Yep
Small world aint it?
Good to see you didn't waste any time plugging it in
Hope it gives you many years of faithful service
cheers

Nick