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Simon-UK
7th September 2005, 05:13 AM
I have acquired an 'S' shaped / curved burr that I would like to turn into a twin bowl on feet.

However, I have only been turning for 9 months and whilst I can knock out respectable round bowls etc this is beyond my experience to date.

There is a 'fat' end and a thinner end to the burr. The idea is to turn a deep bowl into the fat end and a shallow bowl into the thin end. The question is how.

I assume I will need to drill / tap the back of the burr and bolt it to a face plate then turn some feet to glue into the tapped holes to finish. This deals with the deep bowl and should not be too badly out of balance given the weight distribution of the piece.

My question is regarding the overall surface and the thin bowl. Is it realistic to turn the whole face true with a very intermittent cut or do people cheat in some way?

Equally the shallow bowl in the thin end - this would produce a very out of balance item and although I have access to big kit if I talk nicely to the owner (VB36), I am not sure the method is correct. Do I resort to carving and a drill press / mushroom shaped sander for the small bowl?:confused: :o Any help / tips / experience gladly received.

Rowan
7th September 2005, 10:49 AM
if u go to the link in my signature you will see one possible example of what u could do on the main page. While it wasnt turned on a lathe but power carved u can still manage to get nice shapes using this method. Only difference is that u seem to want to turn the outside as well which makes things far more complex.

Simon-UK
7th September 2005, 05:46 PM
The three - bowl piece you show is what I had in mind. The burr / burl I have is an s shape with the bottom of the S much larger / fatter than the top. Therefore, what I have planned is a large bowl in the bottom and a small on in the top.

I intend to leave the outside as is / natural. The reason for the feet (which will be turned from ebony / box - not sure yet) will be to hide the tapped holes I will drill to bolt the burl to the faceplate for turning.

Simon-UK
7th September 2005, 05:47 PM
PS - Rowan - what finish do you use on your projects as they look great!

Wood Butcher
7th September 2005, 07:53 PM
I agree with Rowan. The best way to get the result you want (if I have concieved the right idea in my mind) is to use a power carver like the arbortech on a grinder. Love to try it myself one day!:D

Rowan (the other one).

Rowan
8th September 2005, 11:29 AM
PS - Rowan - what finish do you use on your projects as they look great!

It all depends upon the bowl. Originally I was using Ubeaut traditional wax after sanding to 1200grit. Then I was put onto Mirratone Precat Laquer which I use the 60% gloss and spray on. Just to add to the confusion I also now use EEE utlra shine followed by Shellawax cream on items I have turned, both supplied by or magnanamous host Ubueat Polishes. If u go to the page http://www.ubeaut.com.au/distribs.html u will find where u can get it.

There are probably plenty of products but I luv the ease of use and the great results u get with the Ubeaut products, after of course u sand to at least 800 if not finer!!!!!

disclaimer --- I am in no way related to or employed by Ubeaut Enterprises but possibly should get a commision !!!!

RETIRED
8th September 2005, 04:42 PM
disclaimer --- I am in no way related to or employed by Ubeaut Enterprises but possibly should get a commision !!!!
ROFLMAO. Has Hell frozen? :D

Simon. If you attach the burl to a board that is longer than the burl you can attach a face plate to that and counter balance the larger end with blocks screwed on the board. I hope that makes sense. :)

Rowan
9th September 2005, 10:21 AM
ROFLMAO. Has Hell frozen? :D


always wondered

If hell froze over would it feel like victoria on a bad day???? :D

Simon-UK
10th September 2005, 02:28 AM
Some photos of the piece of timber to aid the description.

Skew ChiDAMN!!
10th September 2005, 03:43 AM
Nice burl!

It'll really test your turning skills... this is where turning can get scary.

I've a few minutes to spare (sleepless night) so I'll bore you with how I'd approach the same job. :D


Firstly, the only way I'd turn this would be with an outboard lathe. The next thing I'd do is make a big ply disk with a radius to match the length of your burl and attach this disk to the faceplate. I'd even consider adding a couple of stretchers across the back of the disk, to each side of the faceplate for reinforcement.

Then I'd mount the burl so the centre of the future BIG bowl is in the centre of the disk. How I'd do this depends on the shape of the back of the burl... If it's a fairly constant width throughout I'd simply screw it to the disk, perhaps using packers so the "face" is squared up on the lathe. Whatever method I used, I'd make damned sure everything was secured!! I do mean everything!

Without any power, the heavy end of the burl/disk assembly should rotate to the bottom. I'd drill a hole through the top of the disk and bolt on a counterweight, normally offcuts of similar sized and weighted wood. Again, I'd make sure everything was secure! No cracks in the counterweight, that it is firmly bolted (hint: locknuts!), no obvious or not-so-obvious knots about to fly out...

I'd spend a bit of time getting the load balanced... the better the balance the safer!! Once all is done to my satisfaction, I'd start the lathe at it's slowest speed; even if iI'd done a "perfect" job of balancing I wouldn't crank the speed up much in case anything comes adrift and, well...

WATCH YOUR FINGERS!! Even at low speed the edge of the burl will hurt if you stick your fingers where they shouldn't be. Or your tools!

Then I'd turn and finish the big bowl before going through the whole procedure all over again for the shallow one. I wouldn't turn the face true (and yes, I would turn it true, no "cheating") until both bowls are turned, as you can't be sure of remounting everything square when "rechucking."

This is also why I'd turn the shallow bowl second, if it was turned first and then rechucked slightly off-square, the difference'd be more obvious than if 'twas the big bowl.

As you realise, it's an intermittent cut. Here you need to be very careful, introducing the tool slowly but with a firm grip. As for finishing the top of the burl, I'd give serious thought to doing that by hand and not on the lathe. It can be done on the lathe, of course, but I don't recommend it for a first attempt...

Errmmm... does any of that make any sense? De nada. I've waffled on, enough that I can think I can get to sleeeeppp... :D