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lubbing5cherubs
29th December 2007, 04:40 PM
Hi Guys, I am at a real loss. I am trying to branch from something beside pens. Made a bowl yesterday well it looked beautiful from camphor laurel. I could see it was thin as with the sun behind I could see the light. Well I went to load it up on the cole chuck so that I could finish the bottom well as I was lining it up I dropped it and the side came out of it. :no: So today I tried to make a bangle I thought how hard could that be. Well it smashed in too pieces. Guys can you give me some really basic idea that I can do because at the moment it looks like pens is all I am destined to do. I have a nova 16-24 and I love to be able to use it full capacity. But every time I try to make something they come off the chuck and become flying catapults through the air. I have tried slow I have tried fast. I tried different angled on the bevel. I just don't think I got the wrist strength to get a tight fit on the chuck. So I am after some basic ideas that I can play with. I right at the moment is feeling quite beat by this bloody lathe and i love turning I just would like to make more than pens kind of waste my lathe a bit.
any suggestions I am just really bummed:C need some ideas because all of mine keep going to the chitter
bye Toni

dazzler
29th December 2007, 05:33 PM
To move on from pens I think u really need to go to a turning class.

But better take some valium first.....all them old blokes that know everything tut tutting that a "woman" is in the place :wink: :p :D

hughie
29th December 2007, 05:58 PM
Toni,
There could be many reasons why things happen.But is sounds like your crunching the wood up or maybe its a bit thin.

But if they fly out of the chuck check, how much grip do you have to start with. Always use the full depth of chuck jaws or at least match the depth of the angled tenon section of the jaws.

I use the wood worm screw on my SN2 for all my roughing out of bowl blanks. The only failures have been on real soft dry timber.
http://www.teknatool.com/products/Chuck_Accessories/SpurCenter.htm
Rough it out with a good base to match the dovetail on the SN2. Then do the inside. When doing the edge or lip of the bowl consider not only how it looks but also a shape that can be held easily by your Longworth Chuck.

Often I use power grip jaws.
http://www.teknatool.com/products/Chuck_Accessories/PowerGrip.htm
but mostly the 100mm or 130mm dia bowl jaws on the base while doing the inside
http://www.teknatool.com/products/Chuck_Accessories/130mm.htm
CL is a soft wood and going real thin is a bit dodgy....:U as you have found :C
I never go under 3mm with it in general use.If you can make the bottom thicker so as to give more grip it will help to hold the bowl together.Also w it will make it more stable when its finished

Longworth chucks; I use mine just to finish the bottoms of bowls. I take light..real light cuts and take my time to finish here and use the chuck in compression only. Expansion is not really very successful...I know I have tried a few times :C :~ :U

Some times on real thin and delicate bowls I put an old towel folded several times on the bed or place them in a cardborad box of similar size while I get organized.


Failing all that have a look at the links below
http://www.turningtools.co.uk/
http://www.woodturningonline.com/Turning/Turning_articles.html#design

arose62
29th December 2007, 06:15 PM
Part 1)
make mallets :D

Part 2)
ensure you have a shoulder on the wod which is butted up against the chuck. The bevel on the wood is only 1 part of a secure grip - the shoulder on the wood is the other part.

Non-serious Part 3)
tell the wood that it's going to be a pen. A very big pen; maybe even a short, wide, bowl-shaped pen, and it will probably cooperate:wink:

Cheers,
Andrew

Calm
29th December 2007, 07:49 PM
Toni

What wood are you trying? I use mainly blackwood or redgum and on bowls i always use a face plate or face ring to finish the outside and then most times to do the inside i use the chuck in expasion mode. I have the hole about 6 to 8 mm deep and on the same angle (roughly) as the jaws on the SN2 chuck. I then finsh the bowl and to remove where the chuck is i use a longworth or donut chuck and most times i bring the tailstock up to help hold it until the very last bit then slowly, slowly and light cuts.

When i made a cyprus bowl it kept coming out of the chuck in expasion or contraction mode so finished both side on a face plate and machined more off the bottom using the Longworth chuck and tailstock.

Keep trying you will get it. i dont think you need to do the chuck up to tight either.

Good luck:2tsup::2tsup:

schaf
29th December 2007, 09:39 PM
Hi Toni,

You live in a big city now. Go find your nearest wood turning club and join up.
You will not be sorry that you did it.

Terry

switt775
29th December 2007, 09:41 PM
All good advice, don't give up too easily. One additional thing to add, very important when hollowing to be certain you are above the centerline, as cutting below centre will create havoc. I know this from experience.:no::no:

dai sensei
29th December 2007, 09:48 PM
I originally went from pens to perfume holders, perfume sprayers, letter openers, nut crackers etc. I also tried clocks, bowls, plates, vases etc. These are all good items to practice turning techniques and finishes.

Cheers

Edit: I must be going nuts. Sorry Toni, I thought you asked another question.

Skew ChiDAMN!!
29th December 2007, 10:07 PM
But if they fly out of the chuck check, how much grip do you have to start with. Always use the full depth of chuck jaws or at least match the depth of the angled tenon section of the jaws.

I'll argue against this... you don't want the piece to use the full depth of the jaws. For "standard jaws," which use a dovetailed tenon, there should be a square shoulder resting against the outside lip of the jaws. (see pic 1) If your tenon is too long then this shoulder doesn't rest squarely...
63405
I should point out that although this shoulder doesn't "improve" grip as such it does increase the amount of leverage that can be applied before the piece is pried out of the chuck.

Edit: I just noticed Arose already said this. Smart man. :wink:

Also, Toni, you want to look at the diameter of the tenon you're using. Close the jaws without anything in them, until the inside edge makes a nearly perfect circle. Measure this, then add a couple of millimetres to allow for the dovetail. This diameter of tenon is what those particular jaws will grip best. (see pic 2) In theory, for 45mm jaws you want a 45mm tenon. For 55mm jaws, a 55mm tenon. I prefer to measure them myself, just to be sure. :)
63404
I'll repeat: even though they'll hold other sizes, this size is where they grip best.

The same is true when you're using them in expansion mode, except you close the jaws until the outside edge is a nearly perfect circle and measure that... subtracting a couple of mm to allow for the dovetail.

Even with the best grip you can possibly have, you'll still encounter UFOs. This is where you start improving your tool technique to take light, quick cuts instead of trying to remove lots of wood quickly. One thing about turning: no matter how good you think you are, there's always something new to learn! :U

lubbing5cherubs
29th December 2007, 10:20 PM
Hi Guys, I feel much better later on tonight. I am now proud owner of 2 bangles and 2 rings I have made tonight on the lathe without it flying out.

I am fine with small things that are close to the chuck like making the bangle I got it tonight. but for things like goblets or boxes well nine time out of ten it a goner.

as for joining the local club. I have done that. I am just having trouble with time.
bye Toni

joe greiner
29th December 2007, 10:54 PM
Hi, Toni. My first bowl-bottom jigs were made from a plywood disk on a face plate (found in a woodturning book), with a groove turned to mate with the rim, then masking tape wrapped around to the back of the disk. I bypassed the Cole jaws and went directly to the Longworth chuck. But I still use the tape to prevent launching. Filament tape is a bit more robust. Two to four wraps of tape, missing the bottom by a few mm to permit a clean cut on the bottom edge. For cross-grain bowl mounting, a bowl gouge is more user-friendly. Joe

funkychicken
29th December 2007, 11:29 PM
Hi Guys, I feel much better later on tonight. I am now proud owner of 2 bangles and 2 rings I have made tonight on the lathe without it flying out.



And here I was just about to tell you how to make them. :~


Just remember, if I can make bowls and platters and boxes and bangles on my GMC lathe, you should be able to do thrice on a Nova.:D

PenTurner
30th December 2007, 08:37 AM
Hello Toni, thanks for raising this thread, I too am wanting to turn other things, but you are way ahead of me. I think I will try to get an experienced turner come over and show me basics before i try anything-by basics i mean just putting something on the jaws! I know it will be simple when once it is done. BTW, show us a picture of those items you made, Amos:) good luck.

robyn2839
30th December 2007, 10:37 AM
lidded boxes,salt and pepper grinders ,pot pouri thingys,clocks,40 year calendars, there are so many things you can do on a lathe,maybe we should have a post on (what you make) on your lathe
would be interesting to see what people make ,and also get ideas. dont give up .bob


_)

Woodlee
30th December 2007, 11:53 AM
Hi Guys, I am at a real loss. I am trying to branch from something beside pens. Made a bowl yesterday well it looked beautiful from camphor laurel. I could see it was thin as with the sun behind I could see the light. Well I went to load it up on the cole chuck so that I could finish the bottom well as I was lining it up I dropped it and the side came out of it. :no: So today I tried to make a bangle I thought how hard could that be. Well it smashed in too pieces. Guys can you give me some really basic idea that I can do because at the moment it looks like pens is all I am destined to do. I have a nova 16-24 and I love to be able to use it full capacity. But every time I try to make something they come off the chuck and become flying catapults through the air. I have tried slow I have tried fast. I tried different angled on the bevel. I just don't think I got the wrist strength to get a tight fit on the chuck. So I am after some basic ideas that I can play with. I right at the moment is feeling quite beat by this bloody lathe and i love turning I just would like to make more than pens kind of waste my lathe a bit.
any suggestions I am just really bummed:C need some ideas because all of mine keep going to the chitter
bye Toni

My wood turning lathe experience is only what I did at high school many years ago ,we made spindles , salt and pepper shakers and stuff but I remember turning a wooden bowl , we had an old Woodfast if I remember correctly , it had a face plate with a wooden face on it amongst other tooling..
We cut our blank and made it as round as possible and marked the centre ,there was a screw in the centre of the face plate that just stuck through a little as a locator .
We cut some white paper and glued it to the face plate with pva glue and then glued the blank on top of that locating the marked centre on the screw and clamped it up to dry.

We turned up the bowl and and did the back of the piece as far as we could ,and did the finishing .Then we removed the face plate from the lathe and used a chisel to split the bowl from the face plate ,the paper under the bowl split in half.
Then we finished the bowl bottom with a no 4 plane.

I know this method dosn't meet the advanced technological standards of today ,but it worked for us .
Maybe this is worth a try .
Does anyone use this method today ?
I would be interested to hear if any one knows or uses this method still.

Kev.

OGYT
30th December 2007, 03:19 PM
Toni, I use the best of both worlds... (I haven't sent one into orbit in many months, now.)
Hughie's world... use the full depth of the jaws. (Just don't make the tenon so long that it touches against the bottom of the jaws, because it may make the piece set "off-round". But using a longest-possible tenon , the solid (or slick) part of the jaws will also grip, and also add a little sideward stability.
and
Skew's world... I always try to make sure the dovetail that I cut in the tenon is a very close match to the size (but not larger) and angle of the dovetail on the jaws, and make sure that the tenon shoulder is flat, so when you tighten the jaws, the dovetail actually helps to "pull" the shoulder of the piece tighter against the face of the jaws.

Something else I just thought of, is to tighten your chuck at both chuck key insertion points... I tighten the chuck, and then rotate it around to the next key position and tighten it a little more... takes the slack out of the worm gear inside the chuck. This is in the instructions from Teknatool (that traitorous company that just recently out-sourced it's manufacturing to -dare I say it - China).

Skew ChiDAMN!!
30th December 2007, 03:54 PM
I know this method dosn't meet the advanced technological standards of today ,but it worked for us .
Maybe this is worth a try .
Does anyone use this method today ?
I would be interested to hear if any one knows or uses this method still.

Yes. I dislike that method for larger pieces, but I use the ol' brown paper bag trick for split turnings and smaller faceplate pieces. :)

There must be several dozen different ways to mount blanks; the skill is to know a few and which to use when. Personally I think that we, woodturners in general, have grown lazy and try to mount everything in a chuck - even when it's not the best method for the application.

I've taught a few young blokes to turn (well - introduced them to turning. I'm not a good teacher and wouldn't call myself one. :B) and I've always tried to put them off buying a chuck until they need one. While they're with me they learn to use faceplates, jam chucks, etc. and even make their own chucks for specific applications.

lubbing5cherubs
30th December 2007, 11:06 PM
I have done it. I rang up and got myself into some beginners class. I am so excited
bye Toni

hughie
31st December 2007, 07:28 PM
I'll argue against this... you don't want the piece to use the full depth of the jaws. For "standard jaws," which use a dovetailed tenon, there should be a square shoulder resting against the outside lip of the jaws. (see pic 1) If your tenon is too long then this shoulder doesn't rest squarely...




Skew your right I was considering longish pieces for turning bangles rather than bowls. With these I use the 50mm power grip jaws and grip along the whole length of the jaws

Did not explain myself well :C........ woefull actually




I should point out that although this shoulder doesn't "improve" grip as such it does increase the amount of leverage that can be applied before the piece is pried out of the chuck.


Well said! something else I forgot to mention. :C

I occasionally place a flat disc on my worm screw between the blank and the chuck for similar reasons.

be glad when 08 here :U

powderpost
1st January 2008, 09:09 PM
Toni,
If chucks are a bit threatening, try this. Take a piece if timber about 150mm diameter and about 50mm thick and fix it to a face plate with screws. The surface with the screw holes will be the the top of the bowl later. Turn the back of the bowl, sand and polish the hollow only, not the rim. See the first part of the attached sketch. Unscrew the bowl and replace with a piece of scrap, about 100mm diameter and about 50mm thick. Turn the shape in the second half of the sketch so the the 'rim' of the waste block matches the base of the bowl. Glue the two together without paper in the joint. I have too many bowls become airborne because of the paper. Turn the hollow of the bowl, sand and polish if you like. Now take a hand saw and cut the bowl off the stationary lathe by cutting the waste block. Clean up the bowl bottom by what ever means you have. Keep the bowl design a simple hemispherical shape. This method, while not very 'exciting', is cheaper than buying chucks and will increase your confidence and lead to more adventurous designs.
Jim

lubbing5cherubs
1st January 2008, 10:47 PM
Thanks for that JIM I think I can do that
bye Toni

Evan Pavlidis
2nd January 2008, 04:03 AM
Also Toni, make sure your tools are always sharp; a blunt tool can create havoc; you end up forcing the tool into the work instead of the tool doing the work for you. Borrow books from your local library or buy them for reference for those times when you don't have an instructor next to you. I cannot count how many times I keep referring to my books, they are a gold mine of information.
Sometimes the work piece flies off the chuck due to a small crack in the tenon which could be difficult to notice. Never mount cracked timber on your lathe no matter how big or small.

Hopes this bit of info helps.
Evan

rsser
2nd January 2008, 01:44 PM
very important when hollowing to be certain you are above the centerline, as cutting below centre will create havoc.

This needs to be qualified a bit.

Depends on what you're hollowing ... deep hollowing on the equator or open bowl 'hollowing' ... and what tool you're using.

For eg. scraper hollowing a lidded box I'd be aiming for the equator; for opening out a bowl, to keep the gouge bevel rubbing you have to go in at the equator then up and around to the centre. For scraper finishing of the inside of a bowl never go above the equator.

powderpost
2nd January 2008, 09:43 PM
I beg to differ... When scraping inside anything it is most important to keep above centre. If you are scraping on or below centre, a 'catch' will force the cutting edge of tool into the wood. Above centre, a catch will force the cutting edge into thin air, no dig in.
Jim

joe greiner
3rd January 2008, 01:24 AM
Scraping outside: Below the equator.

Scraping inside: Above the equator for the walls; below the equator for the bottom. As you work around the inside corner, roll the tool to change the effective equator location. The effective equator location can also be adjusted by rocking the tool handle with respect to the toolrest, so the tool rest needn't be re-adjusted.

As said, the objective is to let the wood move away from the cutter to reduce catches.

Joe

rsser
3rd January 2008, 06:54 AM
As I said, it depends on the object and on the tool.

Think about a lidded box with straight sides and flat bottom and you're using a square or 89 degree end scraper. For the bottom you can position the cutting edge at, above or below the equator since the bevel will give you catch clearance - except of course at the corner where given the diameter of the vessel and the thickness of the scraper and whether you've relieved its left side you are likely to need to be a bit above the equator.

Then think about end-grain cutting of the vessel to thin the walls. Those 3 factors do more to determine where you position the cutting edge than the need for catch clearance. Often you can't see clearly where the tool end is but a relieved side and 75 degree end bevel gives you enough fudge factor.

I do damage with this sort of turning more by tool chatter due to long overhangs than by catches. And yes, catches at the base happen when I inadvertantly bring more than a third or half of the cutting edge in contact with the wood.

In general it would seem that if you need a catch to push the tool away then it's less a matter of the edge's relation to the equator than it is the angle of the shaft to the lathe axis.

rodent
8th February 2008, 05:27 AM
Tony instead of goblets try egg cups there smaller and not as long in the neck so there is less leaverage on the blank and less flybuys .