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comgreserv
8th July 2012, 01:55 AM
I am wondering what thickness is minimum for slabbing logs into for turning blanks? 50mm for shallow platters? Obviously as thick as possible is nice but will be air drying and will want to move stock on (well only the stuff I can't use) I have access to decent logs so it will be large diameter blanks:) And whilst I'm asking what about dimensional stock? 75,100, 125, 150 square?
Thanks all.

Paul39
8th July 2012, 06:14 AM
The blanks will warp some, so allow for that. I do mostly bowls. Most fall in the ratio of 1 high to 3 diameter - 15 inch bowl is 5 inches high. Some are flatter, some are deeper.

Rule of thumb for drying around here - moderate climate more or less 50% humidity - is one year of drying time per inch of thickness.

I do not mill my logs. I split down the middle and make each slab 2 times the diameter to allow for end checking and splitting. I pick up slews of wood off the side of the road and heat with wood so nothing goes to waste.

To speed the process of bowl making, I split timber just off the stump, cut the corners off with a chain saw and rough out the bowl on the lathe, making the thickness of the bowl 15 to 20 % of the diameter. It then goes into a solution of 50% hand dish washing detergent and 50% water for 2 to 4 weeks.

It is then taken out and drained and left to sit in the basement on a rack, or sometimes microwaved until it is too warm to touch, left to cool and repeat, over and over.

You can find all manner of suggestions about drying timber and drying roughed out pieces. Do a search here and on Google.

TTIT
8th July 2012, 10:15 PM
Haven't really thought about it before 'cos I usually just cut the biggest I can from whatever I've got but Pauls 1:3 ratio sounds like a good idea - width of log divided by 3 should cover closed bowl forms OK too.
For dimensioned stuff, I always go for the biggest I can get out of it but then I don't mind that it takes longer to dry - it's going to be more years than you can poke a stick at before I get back to turning it anyway :shrug:

TurnedByIan
10th July 2012, 09:48 AM
Don't forget to make some different blank types other than bowl and platters.
Make box blanks, hollow form blanks, even some pen blanks from interesting bits of grain.
In the early years I used to make everything into bowl blanks. Now that is all I can turn until the next lot finishes drying LOL.
I made my wife laugh one day by standing in front of the woodpile and exclaiming "All this wood and nothing to turn!" (she says the same while standing in front of the wardrobe)
Cheers Ian

hughie
10th July 2012, 10:07 AM
Haven't really thought about it before 'cos I usually just cut the biggest I can from whatever


yep pretty well sums it up for me as well

NeilS
11th July 2012, 10:27 AM
Haven't really thought about it before 'cos I usually just cut the biggest I can from whatever I've got

+1

The world is full of smaller logs for smaller bowls

comgreserv
11th July 2012, 12:01 PM
Thanks all for your responses.
So how big is too big? I can cut out to 1.4mts wide and have ready access to those sized logs? Does anyone buy blanks or just use free logs? Am I better off cutting boards and looking at other potential markets? I do realise that a lot of turners are hobbyists with limited funds but where are all the commercial turners, too busy making shavings guess.

hughie
11th July 2012, 01:26 PM
[So how big is too big? I can cut out to 1.4mts wide and have ready access to those sized logs? Does anyone buy blanks or just use free logs? Am I better off cutting boards and looking at other potential markets? I do realise that a lot of turners are hobbyists with limited funds but where are all the commercial turners, too busy making shavings guess.

[/QUOTE]


Turners do buy blanks but not run of the mill timber. Highly figured timber is the go, fiddle back from the base of large trees etc. Something with colour and character etc.
Slabs sell for table tops, I think from memory 50mm thick 1mx1m is around $800. But the market is not huge and its mainly on the east coast here.
Then if your up to it theres the USA market, our stuff is often deemed exotic and they only see the more common varieties. There are plenty of USA sites selling timber especially burls.

Google USA - Search Google USA for American websites (http://wwp.greenwichmeantime.com/time-zone/usa/websites/google.com/google-usa.htm?cx=partner-pub-0928879361410566%3Ax7bkph-deu3&cof=FORID%3A9&ie=ISO-8859-1&q=turning+blanks&sa=Search)

stuffy
11th July 2012, 01:27 PM
Hi Darren,

It's a difficult question to answer. It depends on the project.

A simple open form bowl in a nicely figured timber in larger sizes and a ratio of say 1:5 can be stunning. Too big can be hard to sell.

It can be difficult to get quality straight grained 100 x 100, or 75 x 75 for table legs etc. Any bigger than that for legs is better glued up.

Lamps, wine tables and pedestals need both nice wide pieces for tops or bases
and straight spindle pieces preferably from the same tree.

Weekend woodies may buy a nice slab for a table and have trouble getting matching stuff for frame. It would be good to have all the pieces needed cut from the same log. Project specific kits.

I guess leave it as long (or thick in this case) as you can for as long as you can applies. Maybe cut thick slabs and pick the best grain to suit each type of project.

Short sections of crotch wood, figured butts and of coarse burls are great for turning and not much good for planks.

Have you got your lathe set up yet?

Feel free to pm me if I can help.

Best wishes,

Steve.
:)

NeilS
11th July 2012, 03:15 PM
So how big is too big? I can cut out to 1.4mts wide and have ready access to those sized logs? Does anyone buy blanks or just use free logs?

The max swing on lathes capable of powering a large blank is between 500-600mm inboard and 750-1000mm outboard. Larger is possible with a free-standing tool rest (see first image here (http://www.woodfast.com.au/index.php?p=1_5)), but there isn't much of a market for such large pieces. Most bowls and platters made and sold are 200-300mm, with a lesser number about 450mm, and few again 500-600mm.

As others have said, both hobby and professional turners will buy blanks, but not just any wood.

comgreserv
12th July 2012, 03:37 AM
Thanks to all who have responded. I should have said it was mainly going to be figured timber from the butt of the tree and other interesting species. I have a log from a peppermint tree that has a few burls on the outside but also a fair bit of rot in the middle. Will have a crack at that one rainy day. Also have a bit of "white cedar" in long lengths and a heap of yellow box still to cut up when I have nothing else to do. lol