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Tiger
24th March 2007, 08:55 AM
Hi to everyone,

I have found that the 2 most difficult cuts for me are back-cutting to hollow out small boxes etc and the rapid peeling cut to remove waste quickly. Both are featured on Richard Raffan videos.

Sometimes I get them right, sometimes it's disastrous especially the peeling cut. What happens is that the wood is splintered and levers right out of the chuck :doh: . I have more success with this cut when using it b/w centres and on greener wood and only when I use part of the edge, I can't remember ever having much success on hard woods. How many turners use these cuts, are they worth the time needed to learn them? They look spectacular when they work but I haven't seen many turners use them at demos etc.

OGYT
24th March 2007, 02:10 PM
I've never seen the videos, and don't know anything about these cuts, but I'll watch this thread to see what others have to say. It'd be nice if someone would try to describe these cuts for those of us who can't afford the videos.
Thanks for posting.

BernieP
24th March 2007, 09:32 PM
G'Day Tiger and Al

There's a pretty good pick of a peeling cut about halfway down the page of http://www.turnedtreasures.com/project.html/rolling_pin/rolling_pin.html

Cheers
Bernie

Tiger
25th March 2007, 08:30 AM
Al,

The rapid peeling cut is made by laying a skew chisel flat across the tool rest and using it as a parting tool to quickly remove waste from a cylindrical (or square) piece of wood.

The back hollowing cut is almost a magical again rapid cut where the inside of a box or perhaps small bowl is removed in a few seconds by cutting in reverse (ie normally you would hollow by cutting toward 10 o'clock, in the back cut, you cut toward 2 o'clock) and using a spindle gouge upside down. It looks amazing when you see it done on the video.

rsser
25th March 2007, 08:36 AM
As for a peeling cut, the version I know involves pointing the skew or beading tool upwards at a fine angle to the work. If I'm getting tugging on the cutting edge then I know to drop the tool handle some more and/or sharpen the edge. For this cut it needs to be super sharp so honing is called for, and the edge needs to be radiused.

There are lots of skilled turners who haven't mastered the back cut btw.

Doc Ron
25th March 2007, 11:15 AM
I can do the peeling cut just fine, but the back hollowing eludes me. I am not sure if I have the right tool shape to do it. I usually get a nasty catch.:~

OGYT
25th March 2007, 03:43 PM
Tiger: The back hollowing cut is almost a magical again rapid cut where the inside of a box or perhaps small bowl is removed in a few seconds by cutting in reverse (ie normally you would hollow by cutting toward 10 o'clock, in the back cut, you cut toward 2 o'clock) and using a spindle gouge upside down.
Thanks for posting. But can you tell me how you use the toolrest when you're trying this? What keeps the tool on the rest? It may be obvious, but I guess I'm missing something. :think: :shrug:

RETIRED
25th March 2007, 04:37 PM
Well sort of.:D

Leave the tool rest in the normal position as you would for the normal cut.

Make your downward cut, roll the chisel so that it is nearly upside down. Let the bevel rub on the cut surface, roll the chisel back until it starts cutting.

Keep the bevel rubbing and apply outward force and withdraw the tool.

It is a hell of a lot easier to do than explain or show. Might see if I can get some pics when there are 2 of us here.

Skew ChiDAMN!!
25th March 2007, 05:03 PM
It is a hell of a lot easier to do than explain or show. Might see if I can get some pics when there are 2 of us here.

Yup. showed us his technique at the Robbofest and I thought I had it memorised. Silly me. :rolleyes: I now have several shelved calamities in dire need of future attention standing testimony to the fact that I don't have a clue. :-

In hindsight, I should've asked Stuart to vid a closeup so I could slow-mo it and see where I'm going wrong. (Not that I'd want to add more to your workload Stu, but I should've! It would've made a good vid segment all on it's own...)

I think it's one of those things that gets lost in the translation when you try to do it slowly so others can watch. [sigh]

baxter
25th March 2007, 05:14 PM
Hi Tiger.

To answer your query I will try to explain how these cuts were explained to me.

The rotary peeling cut is a cross grain cut and is only used between centres or when a cylindrical piece is held by a spigot in a chuck. It should not be used on "square" pieces (before they are turned to round) nor is it suitable for bowls where the endgrain is coming towards the skew chisel.

To start the peeling cut rest the skew chisel flat across the toolrest with the bevel rubbing - the handle is slightly lower than the toolrest. Gradually slide the chisel backwards until the tip is just lifting fine dust. The handle is then raised slightly until the tip of the skew is just below the surface of the wood to make the cut.

If you get a bad catch then you have tried to take too deep a cut. The peeling cut works just as well with both green or dry timber. You should not use the full width of the blade to get a maximum width of cut. Limit the width of cut to about half the width of the blade, then progressively cut another step until the desired width of cut is achieved.

A rotary peeling cut can be done with either a flat or radiused blade skew chisel.

Again the back hollowing cut is only used with endgrain. The cut is started with the spindle gouge on its side with the flute pointing to around 1 o'clock. The tip is just left of centre and is pushed into the end grain (first cut is only about 3mm deep) to create a small opening. Another method, to create this initial opening, is to pre-drill a depth hole into the endgrain.

For subsequent cuts the lower hand (handle) is pulled back towards your body and the tool rotated (from around 1 o'clock to 3 o'clock) to close the flute over, but not to the point where the gouge is upside down. The progressive deeper cuts are made on the upper left tip of the blade and the bevel should be kept rubbing.

The secret is to use the left rim of the first cuts as a fulcrum against the back of the gouge and to use a hand over grip on the toolrest. Because of this it is best if the opening is not widened too early and that you do not try to come to far up the far side of the hollowing towards the rim.

As you get to the deeper cuts, on the far side of the hollow, the tool will be rolling over further to maintain the optimum 45 degree cutting angle. If you start to feel a catch this is a sign that you have cut as far as practical and you should finish off the hollowing by using a scraper in the normal manner.

Hope this all makes sense. I am sure that Richard Raffan would be happy to demonstrate and explain both of those cuts, at the Timber and Working with Wood Shows, when he is a demonstrator.:D

Once mastered (after many failures for the back cut in my case) they are both very quick techniques to remove excess timber.

rsser
25th March 2007, 09:46 PM
You can in fact do light peel cuts to finish the outside of a bowl leaving a very fine finish. Blackwood with messy grain is a good candidate.

Tiger
26th March 2007, 02:45 PM
Thanks for the replies, certainly learnt things I didn't know. John, your instructions are well-written and have encouraged me to keep trying.

Tornatus
27th March 2007, 11:19 PM
John H (Baxter) has given an excellent word-picture of these two techniques, but I think the best advice in his post was to ask Richard Raffan to demonstrate the techniques for you at a TWWW Show. Particularly with the back-cut, the technique will only really make sense when someone shows you how - and makes you do it until you get it right! I am one of the lucky members of the ACT Woodcraft Guild who have Richard to teach us these cuts in person, but even so the back-cut is not for novices or the faint-hearted. Make sure you are comfortable with the standard techniques before trying the exotics - the latter may remove wood faster, but they can also turn nasty very smartly as well!

rodent
2nd April 2007, 02:25 AM
Tiger one thing you must have a lady finger grind on your gouge and on mine i have ground it to a steeper angle so i can get deeper .