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Help Question On Turning Thin Spindles/Legs On Duplicator Lathe


mnrok

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Need advice on turning legs/spindles that taper down to between 1/16" to 1/8" diameter and 2" to 3" long on a duplicator lathe without breaking as many as I turn out!

 

Have a 13 year old CarbaTech mini lathe, 6" swing, 12 1/2" center, and variable speed between 400-4500.  I use a duplicator with templates, sharp carbide cutter and am fairly proficient at woodturning....at least I thought I was!

 

Any secrets on turning really thin spindles.  I know on full size lathes there are what is called a steady rest that is basically a couple of roller wheels that follow the turned piece so that it prevents whip and vibration on long thin turnings.

Is there anything out there similar to this.  On full size lathes you can sometimes hold the piece with one hand while holding the turning tool with the other to prevent whip or vibration.

 

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I work the wood in a chuck as close to the chuck as possible. Slowly work starting at the small end taking very light cuts. Once the small end is finished I go on to the heavy end.  Very sharp tool and very light touch are important.

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Ditto to what Bill said. I make my blank as short as possible and position my template so that the thinnest part of my leg is the furtherest away from the chuck and turn that part first using shallow cuts.

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Hi Elga, missed you at Guild School this year!,

Try this: Turn the thinnest part is NEAREST the headstock chuck. The headstock is the most stable part of the lathe, I agree with Bill, work as close to the chuck as possible. Use your fingers as the steady rest. Turn the entire piece as close as you can get it to the finished size, like a taper. Finish the thickest part, it is stable because it is thick, then gently finish the thinnest part, which is stable only because it is near the headstock. Never go back to the tailstock part once you have thinned out by turning the thinnest part near the headstock. As you are turning the thin part use your fingers to support the thin end.

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I always hold the part in collets….. you only leave what you need sticking out and as you turn keep advancing the work in the collet. I have also made traveling steady rests using a back tool post, a few years back I turned some bamboo fishing rods, the top sections were about .015" thin at the ends tapering to about .025 " at the big end… they were almost 3" long per section. The traveling steady worked great for this.          

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I have tried that Elizabeth, in my case it snapped off. Collets are great Bill, but won't work if you are turning a leg that needs square sections or so I think in any case.

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I'm following the discussion - but mnrok wants to use a duplicator.  I don't have one set up, don't they just follow the profile? 

 

Peter, can you give me more detail about making a soft collets into a square collet?  I bought a 4 jaw chuck.

 

Tamra

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Square collets...see, you learn something new every day! I just did an internet search and saw quite a few different ones, anyone know of a brand that is compatible with the Sherline lathe?

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This is interesting - so many different suggestions!  I would have said, like Elizabeth, to turn the thinnest part last.   It seems like turning the thinnest part first would increase the possibility of breakage while you're finishing the thicker part.  Bill, I'd like to see pictures of your traveling steady rest.  I also have a carba tec and a duplicator, but I've had better luck turning by hand than using the duplicator.

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Has anyone actually used the lathe duplicator from TSC?  or The Anker Duplicator?  The plans for the Anker Duplicator are still sold on eBay.  I think I remember these were suggested for the Dremel, Sherline or Unimat lathes.

 

Tamra/Indiana

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mnroc'

 

 

I am not familiar with your lathe and its capabilities but I, as Bill Robertson does, prefer collets.  I have used and purchased an Anchor duplicator when he first introduced it mounted on a Dremel lathe (lathe POS) changed over to mounting it on my Unimat.  Later changed it to work on my Sherline and Taig lathes.  The advise to start with smaller end still holds in the duplicator.  

 

My most preferred way, is to make a drawing of the piece complete with all measurements and diameters. I mount this on a stiff cardboard and stand it up behind my lathe.  Use a dial caliper to check the measurements on the work against the drawings as I go. I later learned to be more refined in my drawings and measurements after many years at Castine being exposed to Bill Robertson. He has been a strong influence on me.  (Bill's work inspires me to be more precision). As with Bill I work with collets as much as possible too.  I do not use a duplicator any more. I free hand my work with gravers or manipulation of my hand wheels using very sharp cutting tools. If they are very sharp they cut better and lessen the chance of breakage of the part.

 

Although brass ( have turned wood to similar detail and size) the tiny oil cans below are one piece turnings turned on my Sherline by manipulating the lead screw hand wheel and cross slide hand wheel. I have my coordination down fairly well. I cut the spouts first then the body.  The body is done with a series of graduated steps cut to measurements from the drawing. The steps are smoothed out with a series of smaller steps until there are just lines and the rough profile of the body. The body is then finished off with files and polished out.

 

Just practice a lot and keep a waste basket handy.  Good luck.

 

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My husband calls my dremel lathe the fisher price model.  He is  nice :) not to wound my gentle sensibilities.  I thought that was the lathe I needed because when I read the books and magazine, that is what I though that the authors were using.  I can only imagine what he really thought; that might be why he came home one day with the Jet Midi for me.  I didn't even know about Sherline or unimat lathes until I found The Scale Cabinetmaker Magazine.  Did Unimat become Taig?  If not what happened to Unimat?  There must be some kind of history on tools somewhere on the web.

 

(My dremel lathe makes a nice fiber winder when I'm weaving and loading bobbins.)

 

Still, I can't justify a Taig Lathe price tag for my hobby; it seriously cuts into my miniature traveling budget - perhaps if I spent a couple hours a week and made the 100 hours per year mark on my Jet Midi Lathe, and feel like I can turn some wood with some regular expected results - not success by luck, I'll be able to justify it for myself.  Still I am enjoying the thread, and hope the tips continue, as I have a lifetime of learning ahead of me.  If one of you guys could call my husband and let him know you know what the perfect gift for his wife, is... a Taig lathe.. with all the good accessories... hahahah....

 

Gosh Bill, those are some beautiful oil cans.  My dad had some of those in his garage when I was growing up.  I think one can always had 3-in-1 in it.  Can't believe that seeing your miniature oil cans bring those memories up of being his assistant and handing him tools as a child.  I think I need to go buy a RL oil can on eBay!  I wonder if DH (Dear Hubby) has any in the woodshop.... hmmmm....

 

A long time ago, before I had a lathe, David Krupkick told me to make a bunch of the same items and then match them up, ie bed posts, porch posts, etc, etc... - it seemed like reasonable advice.  The turning is easy part, the making 4 identical parts without a duplicator is the-not- so -easy part for me, so a duplicator sounds like a great tool!  I looked at the duplicators for my Jet Midi, and I don't think they are going to work for something so small. 

 

I hope others have experience with duplicators for Real Life woodworking equipment used for scale miniatures.

 

Tamra

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  • 1 month later...

One factor to consider is the wood.  Harder wood might make a big difference.  Fruit wood or maple etc.

 

I turned 80+ miniature oars using a home made duplicator.   The oar blanks were cut from flat sheet from basswood.   Bass is soft and brittle.   The thickest part of the loom was about .156" dia. and tapered down to about .080" near the blade and the grip at it's smallest diameter was about .070"

 

I first turned the loom round the entire length of about 7" between centers.  Then the taper was turned with the grip end in the 3 jaw chuck and live center.   The blank turned end for end the grip was turned and the surplus parted off.  The blade was shaped using a knife and sanding stick.  At the end of each operation fine sanding foam was use to smooth the work.

 

As has been said, working near the chuck is important.  I used a 3 jaw chuck rather than a collet for speed and ease of positioning.  I have collets but the 3 jaw was faster.  I lost a hand full out of about 90 which wasn't too bad considering the task at hand. Most lost were a result of trying to get the job done too fast. I would have preferred using harder wood but these were going to have the blade  completed by kids involved in a museum model boat project.   The bass wood was easier for the kids to cut and shape.

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  • 1 year later...

Today I tried the advance out of the collet method that Bill Robertson mentioned in one of the above posts and so far it is working great, we will see what happens when I get to the graver stage. This little spindle is for the fire screens I am busy making out of mopane, my prototype was made out of cherry and I managed to turn that full lenght out of the collet but no ways that is going to work with mopane...I know because I tried that.

My first step was to just turn what will become the rings all to the same diameter, and the in between spaces just a tad thinner, I then cut it off from the thicker end so that the spindle would be able to slide right through the collet and then very carefully made the spaces thinner between the rings, clamping the wood on a ring as I advanced it out, this spindle is symmetrical so both ends need to be thin.

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I worked on my first test pattern for a lathe duplicator tonite, I'm having am intro to turning class for my miniature club in a week.  I'm setting up a lathe for duplicating.  When I make my pattern do I cut to the outside of the line to give the student more wood to fine tune the turning with sandpaper?

 

I found some 3/16" Masonite at the fabric store that was sold for signs; the material cut easily with my jewelers saw, I cut out a bed post tonite and will test it on the duplicator this weekend. 

 

What is your preference?

 

 

Tamra

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It really doesn't matter where you cut your pattern, on the line, outside the line...the thickness of your final piece all depends on how you set up your duplicator cutter in relation to the wood blank. It is always best to do a test turning, you can tweak how deep the duplicator cuts afterwards, my test pieces often came out either too thick or too thin, and then I had to made adjustments to get it to cut to the right depth. I don't like sanding to get it to the right thickness, if your cutter is nice and sharp you shouldn't need to sand a lot.

Good luck with your class.

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To set up your duplicator. Place a center in the head stock of your lathe.  Loosen the set screen the follower and set the cuter on the point of the center. Push the follower up against the white plastic clamp of the duplicator. Set the set screw.  Now the duplicator is set up.  Notice that on the pattern I sent I have scribed a center line.  Align that with the face of the clamp and tighten the clamp down. Make a test turning at the highest point of the turning and check its diameter.  Adjust the pattern as needed. 

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Oh believe me, I am testing all three of the lathes!  Ok - off to do some test runs!

 

I've never used a duplicator before - nothing like putting yourself to the test eh? 

 

Tamra

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