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Grumpy John
29th July 2008, 06:05 PM
A couple of weeks ago Calm (David) loaned me his Woodcut Bowl Corer. Yesterday I had a chance to try it out on some Blue Spruce. Managed to get 6 blanks from two pieces of timber. I have since been scouring the net for more information on bowl savers and came across this article http://www.morewoodturning.net/coring.pdf. The trouble is I cannot for the life of me find the final two articles which appeared in the January and February 2004 edition of More Woodturning. Would anyone out there be able to point me in the right direction to obtain these articles. Also what are other forum members experiences with Bowl Savers/Corers, and any recommendations.

Cheers
GJ

westpest
29th July 2008, 06:35 PM
Sent a PM

lubbing5cherubs
29th July 2008, 07:29 PM
Hey John what do you think of the equipment are they worth money. I have been considering getting one because i hate how I waste all the centre on nice wood so what is your thoughts?
Toni

Calm
29th July 2008, 07:44 PM
John

i am totally disapointed. When i lent it to you i expected nothing less than a full review including video - of quality no less than DJ's ca pen vid - :D:D:rolleyes:

Now i will have to wait to see what DJ can come up with. aaaah well i should hve had a contract i suppose:p:p

How are you going to hold the "cores" to turn a tenon on the base??

Cheers

Chipman
29th July 2008, 08:09 PM
I would be cutting a pocket in the centre of the core with a 50mm forstner bit. The same pocket will act for all the cores.

Cheers

Chipman:)

Calm
29th July 2008, 08:19 PM
What i did was mount the blank on a face plate or by recess on bottom of largest bowl.

Cut the cores out smallest to largest then mounted the cores in a longworth chuck and machines recess in bottom of each "core blank" to hold in chuck to finish off.

If they are out of "green" timber it would be interesting how much distortion while drying before you finish them.

Interested in other methods that are used.

Cheers

Jim Carroll
29th July 2008, 08:27 PM
What I have found is easiest is to remount onto the original faceplate and shape the foot for the jaws you are using then turn around and save the next bowl.

If you are using a faceplate ring you dont need to take this of the blank.

Calm
29th July 2008, 08:46 PM
What I have found is easiest is to remount onto the original faceplate and shape the foot for the jaws you are using then turn around and save the next bowl.

If you are using a faceplate ring you dont need to take this of the blank.

So you remove the largest core first, whereas i was removing the smallest first.:2tsup:

Grumpy John
29th July 2008, 09:27 PM
So you remove the largest core first,......

This is the way I was doing it, as shown on the vid supplied. Will post photos on the weekend, sorry no video.

GJ

Calm
29th July 2008, 09:39 PM
You watched the video first:oo::oo::?:o:o

I thought they were like instructions, you try to find where you put them when it doesn't work:D:D

tea lady
29th July 2008, 10:50 PM
Could be a team project for the mini turnfest.:2tsup:

Chipman
30th July 2008, 12:27 AM
Maybe I have been doing it the wrong way...

I always use my chuck... never a face plate... To turn a bowl, I cut a pocket in the top of the blank with a forstner bit and then mount the blank on the lathe so I can turn the base and a tenon to hold it. (for thin blanks where I am trying to maximise the depth, I pre-glue scrap onto the bottom and turn the tenon on this)

When I am ready to turn the inside, I take the blank off and turn it around and mount it by the tenon.

Finally, I remove the tenon, mount the bowl in a jamb chuck or on a former and double sided tape so I can clean up the end.


Bowl Saver
I would assume that if you were cutting cores from largest to smallest, you could simply just turn the core(s) around and use the pocket you cut to mount the blank in the first place and then cut the tenon(s) on the successive bases.

If I am doing it wrong, I would appreciate any advice.

Cheers,

Chipman:)

Jim Carroll
30th July 2008, 10:16 AM
With working from largest to smallest and having the faceplate ring on the front it is easy to remount .
You put the ring back onto the chuck and turn the tenon so you can then put the peice back in the chuck and core out the next peice.

You always have the tenon there so when you come back a lot later there is something to grip onto and you can then reshape the peice if need be.

Sawdust Maker
31st July 2008, 08:46 PM
But is it any good :!

Jim Carroll
1st August 2008, 09:54 AM
But is it any good :!


Of course :D

Sawdust Maker
1st August 2008, 07:49 PM
Jim
I was somehow expecting that comment from you :U
You've got to say that so I'll buy one from from a reseller of such down Geelong way!! :D:o I believe they are on special as well. hmm father's day is coming up

Anybody else got a comment? (not that I'm doubting Jim's word :roll::no:)

Grumpy John
1st August 2008, 07:57 PM
Has anyone out there had a chance to compare the Kel McNaughton Centre-Saver System against the Woodcut Bowlsaver. Interested in any opinions and/or experiences with either system.

Jim Carroll
2nd August 2008, 11:00 AM
John the biggest difference between the two is that with the Mc Naughton system you dictate where the cutter goes which can give you a bit more flexibility in shape.

The Woodcut one has the dedicated arc which gives you the standard bowl shape but you can still work around this a bit.

The mc Naughton one is a more physical one in that you need to push a lot harder and hang on more where the woodcut is in the guide and you push it in slowly so not so physical.

The one down side with the Mc Naughton one is that if you pick the wrong angle you go through the side real easy, with the laser guide on the woodcut you can see where you are going so can adjust before starting

Hope this helps.

Grumpy John
2nd August 2008, 07:16 PM
OK people FWIW here is my review of the Woodcut Bowl Saver. Last Sunday & today I have spent probably 10 - 12 hours in total using Calm's Bowl Saver. I have used it on 3 pieces of Blue Spruce 1 Piece of Spalted Blackwood and one unidentified timber (will find out what it is at DJ's tomorrow and let you know). All pieces were felled approximately 6 weeks ago and so are very damp. The Spruce and Blackwood were between 320mm & 350mm dia, and 200mm-250mm thick (half round) the unknown timber was ~200mm dia and 150mm thick. Apart from me stuffing up on the first piece of Spruce and fitting the small blade where the big blade is supposed to go the Bowl saver sailed through the Spruce without much hassle. The Blackwood was another story, I don't know if it was because the Blackwood was a bit "spongy" in places or my technique but there was a lot of vibration and I managed to stall the lathe quite a bit :(( (Jet 1642 2HP). The unknown timber didn't fare much better, managed to get a big catch halfway through the first cut and snapped the spigot off the bottom of the bowl :doh:. After that I gave up and packed everything away:giveup3:. As I said earlier it may have been my technique, I may have been rushing things a bit but you have to withdraw the tool frequently to clear the shavings and as you progress further into the bowl the shavings become dust. Most of my problems occurred when returning the blade to the cutting position, as you working blind and have to guesstimate when the tool is about to start cutting again. If there is some dust or shavings that gets caught in the tip you have to push quite firmly to get it cutting again and that's when you get the catches and the lathe stalls (or snaps the spigot off the bowl). Would I buy one? I'd like to try the McNaughton Centre Saver first to compare the two. I think some sort of Bowl/Centre Saver is worth having if you have a regular supply of large blanks that you can get at least two bowls from.
Hope this helps anyone else considering purchasing one of these tools.

Cheers
GJ

Calm
2nd August 2008, 07:22 PM
I have a lump of Blackwood to take to DJ's tomorrow for him to play with.

JOhn how often do you reckon you need to sharpen the tool.

Grumpy John
2nd August 2008, 07:28 PM
JOhn how often do you reckon you need to sharpen the tool.

Dunno David, the tool still seems to have a good edge on it. Like I said I've only done the 3 bits of Spruce and 1 bit of Blackwood (12 bowls in all). Don't know much use you've had out of it.

Calm
2nd August 2008, 07:50 PM
Dunno David, the tool still seems to have a good edge on it. Like I said I've only done the 3 bits of Spruce and 1 bit of Blackwood (12 bowls in all). Don't know much use you've had out of it.

About that or double what you have. It is still practically new.

cheers - see you tomorrow

rsser
2nd August 2008, 09:09 PM
GJ, as Jim suggested, the McNaughton aka Kelton hollower is more flexible as to core shape. There are some other considerations though, that we've talked about on the dog and bone but here's some stuff I've learned for the possible benefit of others:

The Kelton needs a good bit of grunt; it will work with some faffing around on a genuine 1 hp machine, but more is better. To find out more, do a google. Someone out in webland talks about a surfing technique or somesuch, and also to reduce drag by taking a couple of passes at the opening before going deeper.

There is a clearance issue, between the top of your banjo and your centre. There needs to be space for the gate and the tool height. Chk the Kelton website.

Again in webland, there are folk who've reported on techniques for tracking the tool tip. Lasers and templates are mentioned.

I looked into corers a while ago and as much as a new gadget was appealing, not being a production turner I couldn't justify the expense. It seems in terms of turning time, coring with a Kelton doesn't save you any (but obviously gives you some solid timber instead of shavings). Can't speak for the Woodcut.

Also take a look at the Oneway corer. And Vicmarc have a corer for their deep hollowing rest - which, at a price, would give you two tools kindof for the price of one.

As for an order of work, seem to recall something like this, for green timber:

Start with small core-out first.

Reverse that cored piece into the still mounted blank, centre the core at/with the the tailstock and then turn a tenon for subsequent mounting.

Ditto for the rest.

Hope this helps. Not based on experience, just lint left in the brainbox.

Sawdust Maker
3rd August 2008, 08:37 PM
GJ
Thanks for that

rsser
Thanks for you comments as well

I'm not sure I want one because I like shiny things :rolleyes: or ...
But I do like the idea of less shavings on the floor and more bowls from one blank :)

at the end of the day it is still a bit of loot to have to part with

rsser
3rd August 2008, 09:32 PM
Here's another option SM ... cheap(ish) and cheerful, and prob. the progenitor of coring systems:

Use a lance shaped tool.

You won't get hemispheres, you get cones, and though it's not as efficient in saving timber as a curved slicer it can be made in the shed.

Calm
12th September 2008, 09:25 PM
................to take to DJ's tomorrow for him to play with. .

DJ have you had a play with the bowl corer yet??

Cheers

DJ’s Timber
12th September 2008, 09:28 PM
Haven't had a chance yet Dave :no: but it moved from the door to the bench next to the lathe the other day as I am hoping to have a go with it on Sunday or Monday :2tsup:

Calm
12th September 2008, 09:48 PM
Haven't had a chance yet Dave :no: but it moved from the door to the bench next to the lathe the other day as I am hoping to have a go with it on Sunday or Monday :2tsup:

Not rushng you yet - the VL300 hasnt turned up:wink::rolleyes: so i'm not in a hurry for it.:2tsup:

Dont even want it at 's really:2tsup::2tsup:

Cheers

DJ’s Timber
12th September 2008, 09:58 PM
Ohh, you've bought one hey :2tsup:, next meet is at Calm's, when do you pick it up?






















What :o, what do you mean you haven't bought one, you pulling me leg are you :~

:pointlaugh: :rotfl: :harhar:

Calm
12th September 2008, 10:03 PM
Ohh, you've bought one hey :2tsup:, next meet is at Calm's, when do you pick it up?






















What :o, what do you mean you haven't bought one, you pulling me leg are you :~

:pointlaugh: :rotfl: :harhar:

:no::no::no:HAve you noticed the lack of "for sale's" on them lately.:~:((