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tea lady
4th June 2009, 06:31 PM
I nearly planted a chisel in the ceiling today. (Does that make me a real turner? :cool: ) So how DO you do that transition from the side wall to a flatish base without bike clips on your trousers.:C

Calm
4th June 2009, 06:41 PM
Well first you ring Jim - then ........................well you know the rest - yep have your credit card number ready




No i have that same problem and usually if the angle on the bowl gouge (3/8 HT superflute) is not sharp enough to allow the bevel to rub i go to a scraper.

Problem 2 - i have tried with a 1/2 inch roundnose scraper and find once you get 1/4 of the cutting edge in contact i get a catch with that also - so back to the bike clips.


On my last visit to Jeffs (Keiwa) i used his Ci 0 (on a peice of scrap) and found that to be brilliant - the round cutter gave me confidence that i never had with the 1/2 inch scraper.


So back to the start ...ring Jim and you know the rest.

Cheers & hope that helps

RETIRED
4th June 2009, 06:52 PM
Use the nose of the chisel down the side. When you get down near the transition point put the handle across the bed and use the side.

I use the side for the whole cut and just slide it across the base.

Requires practise.

tea lady
4th June 2009, 06:59 PM
Use the nose of the chisel down the side. When you get down near the transition point put the handle across the bed and use the side.

I use the side for the whole cut and just slide it across the base.

Requires practise. Was trying that, but it gets a bit jittery on the transition. Kinda worked rubbing the bevel all the way round (if that makes sense.:C ) Ended up going the 80# gouge to clean it up. :roll:

wheelinround
4th June 2009, 07:03 PM
How far in have you got the tool post TL

RETIRED
4th June 2009, 07:18 PM
Was trying that, but it gets a bit jittery on the transition. Kinda worked rubbing the bevel all the way round (if that makes sense.:C ) Ended up going the 80# gouge to clean it up. :roll:Requires practise.

Calm
4th June 2009, 07:23 PM
Requires practise.

So in the meantime TL stick with the bicycle clips:D:D:D

Skew ChiDAMN!!
4th June 2009, 07:29 PM
Standing in a tray is better: easier to empty afterwards. :p

jefferson
4th June 2009, 07:56 PM
The Ci0 that Calm referred to is one of my latest additions. It's a Ci1 look a like, only with a round carbide insert. It is great for rounding the transition on the inside of bowls, especially when you get some rippling.

A HD scraper would do the same job, but you'd need a few ground to different angles. I really do like the heft of the tool and now have a spare 1/2 inch round nose scraper looking for a good home....

I'm still road-testing the Ci0 and will give a full novice report after some more testing.

BTW, shaped one of my bowl gouges differently so it was better on the "turn". Not a lot of bevel support, but it works. Perhaps the Spindle Master can explain better than I.

Another topic for our sharpening day.

Jeff

nalmo
4th June 2009, 10:59 PM
I go as far down the side as I can with a bowl gouge with a shallow bevel, which gets me just past the transition from edge to base. Then I change to a larger bowl gouge with a steeper bevel to do the base. I prefer the larger gouge due to its extra strength as you're hanging further over the tool rest. If need be, I finish up with very light cuts with a 38mm round nosed scraper, or a smaller size if this won't fit into the transition space.

oldiephred
5th June 2009, 08:59 AM
Personally the only tool I have had continued success eith inside bowls is an Oland tool.
However, it is very important to keep the overhang as small as possible. Don't try to do the entire inside with one setup of the tool rest IMHO of course:roll:

Cliff Rogers
5th June 2009, 11:32 AM
Practice practice practicepracticepracticepracticepractice

Start with a shallow platter form hollow in a bowl blank & just keep making it deeper & deeper until you have a bowl.
As it gets deeper, you will work out (eventually) how to roll the tool to keep it cutting on the sweet spot while still keeping the bevel rubbing.
Once you have the feel for it, (takes practice) you will be able to do the whole cut from rim to centre in one pass without stopping.

dai sensei
5th June 2009, 12:18 PM
Practice practice practicepracticepracticepracticepractice

Start with a shallow platter form hollow in a bowl blank & just keep making it deeper & deeper until you have a bowl.
As it gets deeper, you will work out (eventually) how to roll the tool to keep it cutting on the sweet spot while still keeping the bevel rubbing.
Once you have the feel for it, (takes practice) you will be able to do the whole cut from rim to centre in one pass without stopping.

:whs:

Mind you, I have only got the hollowing down pat in one direction at a time - ie on the way in, or on the way out. I still cant get the all the way in then all the way out in one motion that and other more experienced turners have shown me.

Practice practice practice

Farnk
5th June 2009, 12:21 PM
Very small Gouge cuts with the chisel rolled over was my method.
SO then bought me the Sorby hollowing tool. Much easier with that.

PAH1
5th June 2009, 01:05 PM
A 1/2" scraper is a bit light for the sort of thing that we are talking about here, you are likely to wind up with a bit of self feeding and some flex in the tool. Richard Raffans instruction is to use the biggest scraper that you can get into the object to do it, this does work and with practice you can take 1/2" wide THIN shavings and clean it up.

Jim Carroll
5th June 2009, 01:49 PM
Practice practice practicepracticepracticepracticepractice

Start with a shallow platter form hollow in a bowl blank & just keep making it deeper & deeper until you have a bowl.
As it gets deeper, you will work out (eventually) how to roll the tool to keep it cutting on the sweet spot while still keeping the bevel rubbing.
Once you have the feel for it, (takes practice) you will be able to do the whole cut from rim to centre in one pass without stopping.


Also go to a smaller tool say 10mm as this has a smaller cutting edge and takes smaller bites, slow the feed rate down as well to get less tear out.

If all else fails use a 40mm scraper as it has mass on its side and a long handle to get good control.

rsser
5th June 2009, 05:53 PM
Yeah.

The 1/4" P&N bowl gouge is a neat tool but you need a curved rest for it.

[Edit: it's 5/16" rod actually :- ]

tea lady
5th June 2009, 11:48 PM
Had a turning session today, and tried various grinds out. My conclusion is that you have to have the grind just so, so that when you go down the side the bevel on the other side of the gouge comes into contact with the base just at the change over. and I have dubbed the grind the 1/2 Elsworth, or the Robbworth. :D It prolly has to be different for every profile. :think: So how many bowl gouges do I need now. :rolleyes:

mick61
6th June 2009, 12:29 AM
G`day that`s a good question. 2 would be my answer with two different grinds then the 1/4inch and bicycle clips.
Mick

tea lady
6th June 2009, 12:32 AM
G`day that`s a good question. 2 would be my answer with two different grinds then the 1/4inch and bicycle clips.
Mick A Robert Sorby is on my xmas list.:cool: The parabolic inside shape is really nice. :dreaming:

thefixer
6th June 2009, 12:45 AM
Had a turning session today, and tried various grinds out. My conclusion is that you have to have the grind just so, so that when you go down the side the bevel on the other side of the gouge comes into contact with the base just at the change over. and I have dubbed the grind the 1/2 Elsworth, or the Robbworth. :D It prolly has to be different for every profile. :think: So how many bowl gouges do I need now. :rolleyes:


I keep the same grind and angle on my gouge for any shaped bowl. I reckon if you keep changing the grind then you have to learn to get a new feel for that angle. When turning different shaped bowls I change the pitch and rotation pattern of the gouge to suit the shape of the bowl. A little hard to explain really, but if you start hollowing from the centre and work your way out from there then you get a better feel for the shape you want. When I reach the transition area as I get deeper into the bowl I drop the handle, rotate the gouge slightly clockwise and then when I reach the the cross grain I lift the handle, rotate anticlockwise and bevel edge all the way to the centre.It must be in one smooth motion though.Ooh I love that swish sound and to watch those curlies come flying off the gouge. Not sure if that is the recognised way of doing it but it works for me and I get a nice smooth finish through the entire bowl and it minimises the sanding. And that's working left handed while standing on the wrong side of the lathe. I never get a catch either when using this method and I don't need to stand in a tray either:oo: This is a method that has taken me hours and hours of practice to achieve and as I said, it works for me but necessarily for others. Molly dukers:p go figure:D


Cheers
Shorty

mick61
6th June 2009, 12:50 AM
G`day I thought that for a bowl you have to cut from the outside to the centre and for boxes(endgrain) inside out?
Mick:D

thefixer
6th June 2009, 01:26 AM
G`day I thought that for a bowl you have to cut from the outside to the centre and for boxes(endgrain) inside out?
Mick:D

Don't know what the correct method is, if there is one:D All I know is I can chew the guts out of a bowl with a gouge working from the centre to the outside as quick as those tungsten tip tools and that gives me the feel for what I am looking for as I am working my outwards.Not sure if that makes sense but as I said it works for me. Maybe as I'm a lefty I'm doing it all backwards:oo:

Cheers
Shorty

rsser
6th June 2009, 06:05 AM
(When does a bowl gouge become a bowel gouge? .... )

Manuka Jock
6th June 2009, 09:37 AM
(When does a bowl gouge become a bowel gouge? .... )

( when ya get the catch of the day :D)

RETIRED
6th June 2009, 09:40 AM
(When does a bowl gouge become a bowel gouge? .... )When you have a catch?:rolleyes:

RETIRED
6th June 2009, 09:40 AM
Snap.:D

RETIRED
6th June 2009, 09:45 AM
G`day I thought that for a bowl you have to cut from the outside to the centre and for boxes(endgrain) inside out?
Mick:DTechnically correct.

I think what fixer is saying that he takes a little from the centre, then takes another bite a little further towards the rim and cuts to the centre and so on refining the shape as he goes.