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HappyHammer
12th October 2007, 01:23 PM
OK guys I've made some shavings !! :o:2tsup::U

I have a couple more questions. I have purchased my SN2 chuck and I've sized the foot on the bottom of my bowl to fit within it, do you think the foot is deep enough for the SN2 to get a safe grip when I turn it around?

Also I've started sanding and there are marks across the grain that I can't get rid of. I started at 80 grit and I'm now on 120 grit should I have persevered longer with the 80 or will these marks come out as I go down the grades?

HH.
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HappyHammer
12th October 2007, 01:33 PM
Oh yeah....any advice on the speed for sanding much appreciated....:U

HH.

orraloon
12th October 2007, 02:06 PM
Happy,
I am still a learner myself at turning but will share a few things I have discovered so far. I have the SN2 and the base of the blank has to rest flush on the jaws rim. It will most likely not run 100% true when you reverse it. I mostly use the jaws in the expanding mode for bowls as any marks left by the metal on wood are hidden in the recess. I do not yet have cole jaws to finish off the foot. When fixing to the SN2 press the blank up to the jaws with the hand flat on the top and tighten gently. Spin by hand to check for true. If it looks close tighten a bit more and a short spin to check for true, standing out of the line of fire when you turn on. If it looks wobbly stop slack jaws just enough to rotate the bowl in the chuck a small part of a turn then try again and so on. You will be fortunate if it is totally true and will have to true the bowl to round again so sanding the outside at this stage is a waste of time. Did you get the instruction disc with the chuck it has some good tips. Tecknatool has a web site also.
When sanding scratches left go back a grade or two if that is required and ensure grit is removed from the work before going to the next grade down.


Regards
John

orraloon
12th October 2007, 02:07 PM
pm. Slow speed for sanding.

arose62
12th October 2007, 02:09 PM
My 2c is to get one of these rotary sanders:

http://www.ubeaut.com.au/ubhome.htm
(scroll down the left hand menu)

When you're doing a bowl, you're changing from with-the-grain to across-the-grain twice per revolution.

I had the same when I was starting out, but using a rotary sander (or sanding disks in an electric drill) fixed it.

Speed?? A few folks recommend slowing the lathe down for sanding, rather than speeding it up.

Cheers,
Andrew

Skew ChiDAMN!!
12th October 2007, 02:15 PM
:wts:

Slow speed for sanding - your paper lasts longer (less heat) and cuts better, a rotary sander and go back a grit if you notice stubborn sanding marks.

One thing, I'm not sure if it's the pic or just my eyes... but isn't there a slight taper on your tenon, that's going the wrong way? It oughtta be a dove-tail type of affair with, as John already said, a good shoulder for the jaws to snug against.

weisyboy
12th October 2007, 03:14 PM
you need to keep the paper moving to get rid of those marks dont hold it one place.

as skew said the tennon needs to be a dovetail not a taper or it will just fly off.

looking good so far.

rsser
12th October 2007, 06:40 PM
Are the scratches paper marks? Or tear-out from the cutting?

Calm
12th October 2007, 08:19 PM
Great start to a bowl:2tsup::2tsup:

Wot they all said and when you have finished make a donut chuck and clean up the bottom of the bowl

SANDING well that is the worst part of the whole exercise. Good Luck:D:D

Donut chuck - consists of 2 disks of (ply, MDF, chipboard)
1 Screw one disk to the face plate you have.
2 Cut a circular hole that will go over the bottom of the bowl and sit about 1/2 to 2/3 of the way to the top.
3 Drill 3 or 4 holes through both disks and bolt them together holding the bowl in the middle
4 That is a donut chuck that will hold the bowl and allow you to clean up the bottom. Pictures available if you dont understand.

OGYT
13th October 2007, 02:48 PM
HH, I agree with all the above. Also, if you have a slight depression (groove/dovetail gizmo) right where the tenon meets the bottom of the bowl, it should grip okay. I've used a 1/8" (3.175mm) tenon to hold a 10" (254mm) bowl, when the grain is oriented like that of your bowl. Just don't get heavy handed with your gouge. And, like Orraloon says, you may have to re-true the bowl when you begin hollowing.
Do your scratches come from tearout, as Ern asks, or could they be toolmarks, or the 80 grit, or the 120 grit? I was taught to sand with each grit, until the sanding marks from the previous grit are gone, then make one more pass over the piece. Blast of air will clean off the dust and grit, before you go to the next finer grit... however you do it, it needs to be cleaned off before changing grits.

HappyHammer
15th October 2007, 11:39 AM
Great start to a bowl:2tsup::2tsup:

Wot they all said and when you have finished make a donut chuck and clean up the bottom of the bowl

SANDING well that is the worst part of the whole exercise. Good Luck:D:D

Donut chuck - consists of 2 disks of (ply, MDF, chipboard)
1 Screw one disk to the face plate you have.
2 Cut a circular hole that will go over the bottom of the bowl and sit about 1/2 to 2/3 of the way to the top.?? of the bowl?
3 Drill 3 or 4 holes through both disks and bolt them together holding the bowl in the middle
4 That is a donut chuck that will hold the bowl and allow you to clean up the bottom. Pictures available if you dont understand.
Yes pictures please.

HH.

arose62
15th October 2007, 11:47 AM
Google is your friend!!!

http://www.turnedwood.com/tools&jigs.html

2nd project down.

Cheers,
Andrew

HappyHammer
15th October 2007, 01:35 PM
Thanks Andrew but I went and had a stab at it anyway..here's what I came up with....

HH.

Calm
15th October 2007, 02:13 PM
Thanks Andrew but I went and had a stab at it anyway..here's what I came up with....

HH.

Exactly what i would have sent you. At the WWW show on saturday i bought a face plate ring to fix on to mine permnanently. When i made mine the back plate is the maximum diameter i could turn above the bed and i have already made two front plates with different size holes.

Only thing is put the nuts at the back. (on the face plate side) It will leave more skin on your hands that way.

Great job and keep up the good work.

OGYT
15th October 2007, 03:01 PM
An ingenious fellow from Australia, named Leslie Longworth, designed the best chuck for turning bottoms of bowls. The Longworth Chuck is the best one I have (as a matter of fact, I made two of 'em). Beats my other two donut chucks hands down.
Just Google Longworth Chuck and you'll find it.

Calm
15th October 2007, 03:31 PM
An ingenious fellow from Australia, named Leslie Longworth, designed the best chuck for turning bottoms of bowls. The Longworth Chuck is the best one I have (as a matter of fact, I made two of 'em). Beats my other two donut chucks hands down.
Just Google Longworth Chuck and you'll find it.

My next project Al

I have the pictures and have to work out where to source some poly in Ballarat then i will be right into it.

HappyHammer
15th October 2007, 04:10 PM
Only thing is put the nuts at the back. (on the face plate side) It will leave more skin on your hands that way.
Thanks for the advice but unfortunately I've had to learn from experience. I had the bolts that way originally but they were touching the motor so had to turn them around.

I then lost the skin off of two nuckles:doh: so I'll be buying some shorter bolts.:U

Anyway, here's the bowl, just finished it simply with Olive Oil so I can use it for peanuts. The timber is Queensland Maple and when you move it in the sunlight it changes colour depending on how the light catches it so the picture doesn't really do it justice.

The marks on the foot were made by the chuck when I had a couple of scary catches when I was doing the inside on the SN2 and the bowl flew off of the lathe luckily missing me.:B

Comments and improvement suggestions welcome.....

HH.

Calm
15th October 2007, 04:19 PM
You could use the donut chuck to remove the tenion/foot altogether if you want to.

TTIT
15th October 2007, 04:36 PM
.....................Comments and improvement suggestions welcome.....

HH.Looks a damn sight better than my first bowl - well done mate:2tsup::2tsup: You could probably tidy up around the foot a bit more but bowl #2 oughtta be screamin' out by now eh!:;

Brown Dog
15th October 2007, 04:59 PM
Very nice job for a first effort :2tsup: ...pleasing form (appears to have a uniform thickness) and looks to be nicely finished.

This is just my preference, but on your next go at a bowl try to make the inside curve more rounded... try to keep the curve constant. I always think it looks better on bowls if the inside is one flowing arc instead of having the side...then a flat base

Im with TTIT...looks a dam sight better than my first aswell :U

cheers
BD:peace2:

Skew ChiDAMN!!
15th October 2007, 06:02 PM
It's perfect for peanuts. If you keep it topped up, then no smart-arses will comment about the flat bottom. :wink:


An ingenious fellow from Australia, named Leslie Longworth, designed the best chuck for turning bottoms of bowls. The Longworth Chuck is the best one I have (as a matter of fact, I made two of 'em). Beats my other two donut chucks hands down.

For most bowls, yes. But the donut chucks will hold pieces Longworths or Cole Jaws won't even look at. Plus, they're a lot cheaper, esp. if you make your own. :)

It's definitely a good technique to know and, along with making jam chucks, is something I believe every new turner should learn early on. (Hell, I reckon newbies should be banned from buying a commercial chuck until they've completed a few bowls with jam- and donut chucks. :D)

rsser
15th October 2007, 06:32 PM
Looks good HH.

But I'm sorry to tell you that Olive oil isn't good for wood utensils. It can go rancid. Suggest you wash the bowl in warm water and detergent and try a nut or seed oil.

hughie
15th October 2007, 09:43 PM
Looks good HH. yep go with that too



But I'm sorry to tell you that Olive oil isn't good for wood utensils. It can go rancid. Suggest you wash the bowl in warm water and detergent and try a nut or seed oil.
[/QUOTE]

I use walnut oil, get from the health food shops....bit dear but you dont need much

Christopha
16th October 2007, 09:56 AM
A good start, I remember my first bowl many years ago... it looked like a miniature "Gozunder"..... and not a good one at that!

HappyHammer
16th October 2007, 11:10 AM
Thanks for the comments and encouragement guys. I'll wash it off and use some peanut oil that's lurking in the back of the larder....:doh::U

HH.