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Timbuck
07-07-2010, 04:44 AM
I've just resawn a 2.125" thick Billet into 9 slices for soprano tops and backs....
after thickness sanding down to approx: 4 X .075" & 5 X .0625" .....Then I put them all together and measured them again = about .625"...that means i've lost 1.5" of wood in sawdust:( That's over % 70 of the Billet gone:confused: what a waste of Mahogany.:mad:

funaddict
07-07-2010, 06:36 AM
That's always been the woodturners lament. This hollow vessel is about 10" diameter and 6" tall and 3/16" wall thickness. I'm guessing about 95% of this quilted maple ended up as shavings on the floor, like in this picture of a bowl I was working on awhile ago.

Alan

fahrner
07-07-2010, 08:38 AM
Every system has its losses.
The pics show the results of cutting sides and backs/tops and then putting the billet back together.
I'm estimating the loss at this point at about 20%. They are not 'final thicknessed' so another 10% for a total of 30% waste..... unless I find a use for the sawdust.

Timbuck
07-07-2010, 08:58 AM
That's always been the woodturners lament. This hollow vessel is about 10" diameter and 6" tall and 3/16" wall thickness. I'm guessing about 95% of this quilted maple ended up as shavings on the floor, like in this picture of a bowl I was working on awhile ago.

Alan

Love the bowl what kind of neck ar you going to fit..and what scale???:D

Pete Howlett
07-07-2010, 09:51 PM
Ken - If it is really precious and deep (I can only saw to 7.125" on my saw) have my wood resawn in the UK - 12 slices from a 2" billet :) It's also a very good surface that requires little sanding...

Timbuck
07-07-2010, 10:21 PM
I started out trying for maximum slices when I first started resawing my own..I aimed at 3mm but had to scrap half co's they wouldnt clean up in the thickness sander:mad:..now I saw them at about 4 mm.....(I don't have to make ukes....it's just that I can't stop:confused: why???

Pete Howlett
07-07-2010, 10:57 PM
You're not using the right blades Ken... sorry to be so forthright but I get that and it is always the blade. I think it's due to poor 'setting'.

Michael N.
07-07-2010, 11:37 PM
I assume it is a Bandsaw that you are using to resaw. Set up is critical, especially when it comes to resawing. Preferably co planar wheels, suitable fence and the guides set correctly. The problem with the smaller type Bandsaws is that they have difficulty getting enough tension in the blade - hence the striations or washboard effect. As Pete states, the correct selection of blade is extremely important

Timbuck
07-08-2010, 12:43 AM
It's a 14" SIP Bandsaw http://cgi.ebay.co.uk/Bandsaw-14-355mm-2-speed-SIP-01489-NEW-/180498118581?cmd=ViewItem&pt=UK_Home_Garden_PowerTools_SM&hash=item2a0686b7b5 I can get 8" clearance...I'm using a 5/8" blade from Axminster at the mo' 3 TPI .. I also use an 1/2" blade at 4 TPI ....could be the tension , but the machine has a tension setting gauge fitted.

Michael N.
07-08-2010, 02:22 AM
Similar to mine except yours has a higher depth of cut. Unfortunately these type of machines need all the help they can get, which is why I say set up is critical. Your tension gauge is probably near useless. It's also worth trying to get the wheels co-planar so that the blade tracks better. That will involve removing the table and you will have to make a long straight edge out of MDF (or similar) with a cut out so that the straight edge is able to register on both top and bottom edges of the two wheels. Search the net for co planar bandsaw set up and you should be able to find the relevant info.
You should also make a high straight edge sawing guide (if you haven't already) that is close to the depth of cut. Just a simple L shape made from plywood and secured to your table with G clamps. Adjust your table so that the blade is absolutely parallel to the resaw guide.
I ditched all the bearing roller guides on mine and simply substituted hardwood (Bubinga) guides that had been soaked in WD40 overnight. You can virtually touch the side of the blades with these guides. The original bearing guides had too much play in them and were a pain to adjust. Of course your original guides may be much better than the ones that were shipped with my machine.
I haven't tried Axminster blades for many years. Ian of Dragon saws supplied the blades that I now have. Both his blades and advice made a huge difference to my machine. He knows all too well about the shortcomings of these machines. Next time you need a blade you would be well advised to phone him and tell him your requirements. Unfortunately Dragon are no longer trading but I have been informed that Ian has recently set up again.

Timbuck
07-08-2010, 05:11 AM
Thanks for that excellent advice...I'll have another go at it soon.

Pete Howlett
07-08-2010, 06:49 AM
What I said Ken - those Axminster blades suck!

Moore Bettah Ukuleles
07-08-2010, 07:54 AM
I have never seen a 14" band saw that consistently does a great job of resawing koa. At up to a hundred bucks a board foot, I send all my koa out to a resawing expert. All it takes is one bad cut in a plank to lose a few sets of wood. I pay $85 and hour and in two or three hours he can cut 100 sets of wood. Once you have a pro cut your wood you'll never look back. Still, there is lots of waste but not only due to the blade kerf or the sanding that needs to be done. Cutting into a large plank of wood can reveal nightmares that can be seen from the outside, including rot, knots, nails and staples. etc.