how to duplicate tapered legs

[Sebastiaan76]

Hi all,
I'm fairly green when it comes to turning, but have a few projects coming up that are going to require turned tapered legs. Not too much in the way of decoration, beads etc, simply tapered round legs that are bigger at the top and smaller at the bottom.

I'm contemplating buying Woodfasts Copy turn attachemnt - Woodfast Machinery Co. (Aust.) Pty. Ltd. - (http://www.woodfast.com.au/index.php?p=1_11)
However I don't think it will fit my Ledacraft mini lathe ( which is 127mm from bed to centre height, and that attachment required a minimum 143mm ).

Question: Other than total skill ( which i don't have ), how else can I achieve consistent duplicate legs? I'm playing around with a jig where a router slides over a template using a pattern bit, but in some of my testing, it seems a bit crazy and dangerous to have the router going over the wood as it's turning, and the whole thing just seems cumbersome and likely to have the router bite in and damage the timber, possibly the bit and scare the crap out of me in the process.

Keen to know if there is some simple jig, or method that I can get pretty much perfect duplicate tapered turned legs. I'm just not game to go to this extreme: https://www.youtube.com/watch?v=he3CDqJhBNY

How do others go about churning out large batches of the exact same legs?

[artful bodger]

To put it in a nutshell you have to turn the larger diameter at one end, the smaller diameter at the other then turn a straight line between the 2. It does not get much more simple, especially if you have a tool rest long enough so that you don't have to move it during the process.

[robbygard]

similar to above but to expand a bit ....

i turn my cylinder to the largest diameter first ....

i draw the leg on thin mdf and measure and mark several spots along it (about 3/4 to 7/8 of the length of my tool rest), transfer the marks to my cylinder and cut the marks with two parting tools, a 1/4 inch wide one down to about 3/16 oversize and a very thin one (i think about 3/32" wide) to 1/16 oversize (and a galbert caliper although any caliper would do) ...

i go a bit under 1/16 inch oversize ... i work from the thick end to the thin end ... i use a steady to avoid getting an oval shape, particularly as it starts to thin out and use a skew to turn the straight line between marks ... once i have all legs to 1/16inch oversize i put them back on and finish them ... (if i have to put a mortise in them, i do that at the stage of it being a cylinder before i turn the shape)

sorry if some of that is a bit basic

good luck

regards david

[DaveTTC]

I draw the angle on the bed as a sight guide too

Dave TTC
Turning Wood Into Art

[oreos40]

370163

routers and lathes go together well in many instances! your situation would be a great application.

https://www.youtube.com/watch?feature=player_detailpage&v=P12E08byJ6k
My lathe has been built with special set ups in mind but for straight tapers you lathe could be easily adapted temporarily with a few pieces of material.

You will need to attach a flat board to the ways of your lathe to serve as a work table. this will be removed when not being used so your lathe can be used conventionally.

You will need to construct a "c" shaped bracket that will hold the router in the vertical position and at the right height off the work surface to cut your rotating stock.

the bottom front of the bracket will become the depth stop

screw a board to the top of the work surface to serve as a template at the desired angle.

if you wish you can rough the stock to the approximate shape first

roughing cuts with the router are ALWAYS climb cuts. (prevents blowouts and digging in)

finish cut is conventional.

Have fun!

[ian]

:wts:

make up a negative template from MDF

use the template to check for consistency between each leg.

REMEMBER
if the legs are for a table, the inconsistency -- leg to leg -- needs to be pretty large before anyone will notice

[Sebastiaan76]

Thanks everyone!, Oreos, I was looking for something like you have suggested. I have a better idea of where to look and things to try now.

Cheers

[ian]

Hi all,
I'm fairly green when it comes to turning, but have a few projects coming up that are going to require turned tapered legs. Not too much in the way of decoration, beads etc, simply tapered round legs that are bigger at the top and smaller at the bottom.

I'm contemplating buying Woodfasts Copy turn attachemnt - Woodfast Machinery Co. (Aust.) Pty. Ltd. - (http://www.woodfast.com.au/index.php?p=1_11)
However I don't think it will fit my Ledacraft mini lathe ( which is 127mm from bed to centre height, and that attachment required a minimum 143mm ).

Question: Other than total skill ( which i don't have ), how else can I achieve consistent duplicate legs? I'm playing around with a jig where a router slides over a template using a pattern bit, but in some of my testing, it seems a bit crazy and dangerous to have the router going over the wood as it's turning, and the whole thing just seems cumbersome and likely to have the router bite in and damage the timber, possibly the bit and scare the crap out of me in the process.

Keen to know if there is some simple jig, or method that I can get pretty much perfect duplicate tapered turned legs. I'm just not game to go to this extreme: https://www.youtube.com/watch?v=he3CDqJhBNY

How do others go about churning out large batches of the exact same legs?may I suggest that your time and dollars is best invested in P R A C T I C E at the lathe.

turning blanks - in the form of construction pine from Bunnings cost almost nothing
by the time you have docked a 3m length of 70 x 45 into 6 x 0.5m blanks and turned each one down into a taper you'll have incurred a total expense of less than $10 AND increased your skill and confidence levels immeasurably.

[derekcohen]

As Ian wrote, make a template. This becomes even more important when there are curves to duplicate.

Here is an example from a chair I built a couple of years ago (from my website) ..

Below are the four cylinders turned for the legs. Note that the ends are left square. These will act as reference for working to square when the mortices are added.


http://www.inthewoodshop.com/Furniture/TheChair-BuildingTheLegs_html_7d9af2f5.jpg


Back to the lathe. The cylinders receive markings at approximately 25mm (1”) spacing with the thickness of the leg at that position.


http://www.inthewoodshop.com/Furniture/TheChair-BuildingTheLegs_html_7b8611c5.jpg


Here are the turned legs with their depths of cut completed. The temptation is resisted to complete a leg before moving on. It makes for greater consistency to do just one task at a time.


http://www.inthewoodshop.com/Furniture/TheChair-BuildingTheLegs_html_m76cd38ad.jpg


Finally the waste was removed from between the depth cuts, and the legs faired with a sanding pad.


http://www.inthewoodshop.com/Furniture/TheChair-BuildingTheLegs_html_2f954223.jpg


Four completed legs. The template is used to check the profile of each.


http://www.inthewoodshop.com/Furniture/TheChair-BuildingTheLegs_html_m7dec70e4.jpg


Here are the legs alongside the chair …


http://www.inthewoodshop.com/Furniture/TheChair-BuildingTheLegs_html_m70785df4.jpg

The link for the article is http://www.inthewoodshop.com/Furniture/TheChair-BuildingTheLegs.html

Regards from Perth

Derek

[springwater]

may I suggest that your time and dollars is best invested in PRACTICE at the lathe.

turning blanks - in the form of construction pine from Bunnings cost almost nothing
by the time you have docked a 3m length of 70 x 45 into 6 x 0.5m blanks and turned each one down into a taper you'll have incurred a total expense of less than $10 AND increased your skill and confidence levels immeasurably.

I'm so glad you said that, it seems to me that routers and lathes go together like beer and marshmallow.

[ian]

Beer and marshmallow I can sort of see going together.

Sort of ...



lathe and router ??

to my mind very very advanced techniques for special applications like fluting.

Definitely not a roughing tool, nor a tool for a beginner

and from the posted video, it seems an awfully slow process

[ian]

Originally Posted by ian
may I suggest that your time and dollars is best invested in PRACTICE at the lathe.

turning blanks - in the form of construction pine from Bunnings cost almost nothing

by the time you have docked a 3m length of 70 x 45 into 6 x 0.5m blanks and turned each one down into a taper you'll have incurred a total expense of less than $10 AND increased your skill and confidence levels immeasurably.I'm so glad you said that, Thank you

[artful bodger]

[QUOTE=ian;1928228]may I suggest that your time and dollars is best invested in P R A C T I C E at the lathe.

Or at least just TRY one for starters.
It is the next easiest thing to turning a cylinder, and you do not need any fancy router attachments.

[Damienol]

Keen to know if there is some simple jig, or method that I can get pretty much perfect duplicate tapered turned legs. I'm just not game to go to this extreme: https://www.youtube.com/watch?v=he3CDqJhBNY


This is awesome

[oreos40]

In the posted video I had 200 of them to do. they are dried oak miniture practice golf club handles. they are fourteen inches long. from square3/4" stock. 5/8" on the big end and 7/16" on the small end with a 3/8" dowell turned on the small end for 1 1/16" they had to be very precise to fit a pre molded handle. The customer had posted on a couple turning sites to get them done and was excused by overpriced stuffed shirts or complaints about difficulty. I did the whole job from scrap wood in a day and still had the evening for a date. I made enough for two days work at my day job and enjoyed it. Why the put downs? Because I don't turn conventionally? I had only one of my blanks end up in the burn pile. they had to finish off +or-.010" of dimension in diameter on the handle and .oo5 on the dowel portion and +or-.032 on lengthwise dim. I guess I would like to see a video from one of the detractors here do just two of them to spec in 5 minutes. there is a reason I have gotten certain jobs over the years, this is one of them.

[ian]

In the posted video I had 200 of them to do. they are dried oak miniture practice golf club handles. they are fourteen inches long. from square3/4" stock. 5/8" on the big end and 7/16" on the small end with a 3/8" dowell turned on the small end for 1 1/16" they had to be very precise to fit a pre molded handle. The customer had posted on a couple turning sites to get them done and was excused by overpriced stuffed shirts or complaints about difficulty. I did the whole job from scrap wood in a day and still had the evening for a date. I made enough for two days work at my day job and enjoyed it. Why the put downs? Because I don't turn conventionally? I had only one of my blanks end up in the burn pile. they had to finish off +or-.010" of dimension in diameter on the handle and .oo5 on the dowel portion and +or-.032 on lengthwise dim. I guess I would like to see a video from one of the detractors here do just two of them to spec in 5 minutes. there is a reason I have gotten certain jobs over the years, this is one of them.OK

I'll take up the cudgel ...


How long have you been a turner?

How long did it take you to build the jig that holds your router and controls its travel? It looks to be made of machined aluminium. Is it?

If the task was to make 4 straight tapered legs -- would the investment in the time and materials required to build your jig from scratch -- even if built from 17mm ply -- be worth it?

What level of skill / experience is required to use your router jig -- especially as I couldn't see how you controlled the change in depth of cut between the first climb cut and the finishing cut. (For me this suggests you relied on muscle memory for the initial climb cut. There's nothing wrong with that -- but presumably your muscle memory has taken some years to develop.)

Is mounting a blank with the lathe running something you would recommend to someone who admits to being "fairly green when it comes to turning" ?




I'm not for one minute doubting your skill as a production turner -- 200 identical turnings to the specs you quoted is ample evidence of that.
But is it responsible to advocate mass production techniques to someone who says of them self "... skill (which I don't have)" ?



BTW -- If I could visit your shed I'd be very interested in looking at your jigs and watching you work, as you clearly know what you are doing.

[oreos40]

I have been turning for almost fifty years. The OP did not say how many he wanted to turn. he asked about duplicating turnings. this is how I duplicate turnings. As I stated in my first post my lathe has been specifically built for quick change overs. There is a template mounted on the rear of the lathe. For individual copying I can mount the original spindle where the template goes. otherwise a piece of 1/8" hardboard for a short run or plexi for longer runs. cut out on the band saw and clean up with a file in a few minutes. a change over between existing pieces can take from 10-30 minutes. If I have to make a new template it may take an our and a half. for something like butcher block table legs and about fifteen minutes to an hour a piece on the machine for each leg depending on pattern. for a straight taper the set up on any regular lathe might take me an hour. the holder for the router would be the only thing that might take time. an hour for the parts and wait til the next day to allow the glue to dry. I used a router for these because they would tend to whip cutting with a regular cutter. Climb cutting pushes the stock over just ever so slightly and leaves an over sized roughed in blank. Then the conventional cut brings it down to perfect size. if you conventional cut on the first pass the bit will pull the stock and you get undersized the first pass every time! LOL I don't know of another turner with a lever action tail-stock. I wouldn't try it with a typical screw setting tail-stock. My dad designed and built the first one before I was born. His business was custom turnings for over 60 years. Here is a video of how the template works. this is the first part of the run. I made it for the customer because they were concerned that I wasn't charging enough to make any money.
https://www.youtube.com/watch?feature=player_detailpage&v=xp39LBNmKZ4

[oreos40]

This is the first couple parts in a following order.
https://www.youtube.com/watch?v=5PycgbO4tK0&feature=player_detailpage

[oreos40]

Anyone is welcome to stop by! just give me time to dust off a bit! lol

[Sebastiaan76]

Well,
Alot has happened in this thread! I've had a PM from another forum member ( very experienced turner ) who has offered for me to come down and get a few pointers in person ( which i'll be doing later in the month ) I'll also be doing more practice as per what Ian has suggested.

Having said that, the longer term goal is to be able to make a heap of these, and do it quickly and easily - so ultimately I was looking for something along the lines of what Oreos is doing. Still, I am keen to learn how to do these things manually as well.

Having looked at the commercial duplicators out there, they all look pretty crappy ( save maybe the Vega one ) compared to what Oreos has built. Seems it's the kinda thing you have build yourself I guess.

Either way, I've gotten a heap of good info and tips from all of you, so many thanks - and by all means, let the Router Jig vs Experience debate continue! :)

[derekcohen]

Well I think what you do is bloody brilliant!

It is also what I might expect from a production line run by a professional. This is very far from the turnings I do as an amateur, where the development of freehand expertise is a central part of the reason a piece made is prized. It is why I cannot connect with those using computers to build furniture, and why I prefer to use hand tools. That is not a criticism of what you do, simply pointing out that the skills to build 4 legs for a table are something that an individual needs to develop through the actual use of chisels.

Regards from Perth

Derek

[ian]

Echoing Derek WOW

Curious -- if you were asked to make 200 lace bobbins, how you go about it?
my younger sister is a lace maker and as I understand it, lace bobbins need to be a certain size, but don't all need to be identical

[Sebastiaan76]

Oreos,
In conjunction with learning more conventional methods, I'm keen to build a jig similar to what you have. Although I'd like to be able to interchange a router with a more conventional blade.

In one of your videos, you are using a stationary cutter instead of a router, are you able to advise where you can get something like this? I was thinking maybe the blade head on a Sorby Turnmaster would be suitable if mounted appropriately - http://www.cwsonline.com.au/persistent/catalogue_images/products/turnmasterunhandled.jpg

[oreos40]

One at a time lol. Can you give me a picture of a lace bobin?

[DaveTTC]

They are just small spindle turing about 150mm long and average about 3mm thick at a guess with some beads and coves

Dave TTC
Turning Wood Into Art

[oreos40]

the difficulty with most of the carbide insert cutters is that in most cases they are a scraper and not applied in shear. For that reason they are generally poor in a cross the grain cut. Those who really get Cutting the wood can if they are careful and present the tool properly get a shear cut with these tools. The cotter you have seen in most of the videos is a standard HSS tool ground with a lot of relief both on the side and on the top. It could not be used by hand! it would tend to self feed and catch with every attempt. there is no bevel to ride to control the chip. I do also use carbide insert cutters. these also have a lot of side relief and also a "chip breaker" relief. These will also lead to exciting catches if used by hand. They are commercially available for cutting aluminum. they come dead sharp on the cutting edge. Most of the inserts out there are ground for cutting ferrous metals and come with what is called a "hone" on the edge and instead of cutting they rub the wood off. The ones advertised for wood may come with side relief but the top is flat with a dead sharp edge. typical grinds for regular copy attachments are also ground with a flat top so that they scrape instead of shear to avoid grabbing and getting a catch. Which is why they notoriously provide a poor finish and require a lot of sanding compared to someone good with a gouge and skew. there is a lot of stuff going on at the cutting edge that many never really get an understanding of. They can be great turners because they find what makes it work but never understand why it works. regular duplicator chain drives are sloppy and dont have a fine enough control on the lateral movement of the cutter. For short items a better duplicator can be made when actuated by two levers and good swivel joints instead of one lever and a chain. the the cutter is ground to look like the front of a canoe and can cut equally well both to the left and to the right and the top relief gives a sharp cutting edge for good surface results.

[Sebastiaan76]

OK, so you have applied more the kind of tools used on Metalwork lathes for your duplicator? i.e. this kind of thing, but then with the HSS bit ground in a custom way?


370624

[oreos40]

tooling is customized to purpose most of the time. If you search oreos40 on youtube I have a few videos that might interest you. the short answer would be yes. tooling is adapted from many places. people use sharpened Allen keys for hollowing and Chinese balls. Some have used files for cutting and scraping. some use profiled scrapers for repetitive shapes. each person becomes comfortable with their own way of doing things. there are several different grinds for a spindle gouge each user uses the grind they use because they have come to be comfortable with it. some will laud superiority of one grind or another. one can learn how to cut with a tool without understanding why it works for them. when and if they come to know why it works it can be like waking up to a new day. most wood working classes teach how to make cuts with a tool, but few if any teach why it works best to do it that certain way as opposed to another. it is not looked at as a waste of time but not necessary if they can just learn to make a cut the prescribed way. I think cutting tool geometry is very important to understand. different material cuts differently. if I sharpen a tool for oak and get a nice of the tool finish there and switch to mahogany I get a fuzzy finish. if I grind for mahogany and switch to oak the cutter will lose its edge quickly.

[oreos40]

3 mm wow thats thin. I will have to try it. I would like to see beads and coves on something that thin. what material? I am certain
it must be riven material to avoid cross grain.

[DaveTTC]

3 mm wow thats thin. I will have to try it. I would like to see beads and coves on something that thin. what material? I am certain
it must be riven material to avoid cross grain.
3mm at the narrowest at a guess

http://uploads.tapatalk-cdn.com/20160205/da0a2a53ded6a1c7c7696aefe745cda8.jpg

Ive never made them. Just seen others

Dave TTC
Turning Wood Into Art

[ian]

Here's some dimensions
The narrow part of the shaft and the head, must be very smooth so that the lace thread doesn't catch on the wood.

The bobbins my sister uses are more in the shape that Dave posted

http://webpages.charter.net/lara_the_lacemaker/bobbinspec.gif

The main elements of a bobbin are:
http://webpages.charter.net/lara_the_lacemaker/bobbin1.gif
a head and neck (where the thread will be attached);
a main shaft, body or shank (held by the lace-maker) and
a tail end strung with beads to add weight and stop the bobbin rolling around on the lace pillow, and to help identify which thread is which.

the ‘neck’. A long length of thread will be wound the neck and stored there, just gradually unwinding as lace-making progresses.This stored thread is held in place by a slightly bulbous knob atone end of the neck (it is the start of the bobbin’s ‘head’) and by the thicker main shank at the other end.In practice, necks vary in length. Longer necks could carry more thread which was useful when either a thicker thread was involved or if a bobbin was being deployed as a ‘worker’. Worker bobbins act like shuttles: they move over and under the other warp-bearing bobbins. The latter,the majority, are called ‘passives’ since they just ‘hang about’ for much of the time, a role that leads them to require much less thread.
Immediately above the knob there is a little recess (the ‘short neck’)round which the working end of the stored thread is hooked and gradually unwinds. It is important that the head of a bobbin is not chipped or broken - if it is, a working thread will easily slip off.

[oreos40]

Ian, Give me a bit. I am a machine designer builder in the middle of several builds. this weekend was my first two day weekend in a while. My wife has planned to have Easter at our home as incentive to finish a 1700 square foot addition on the house and the woodworking equipment in the shop is pushed back against the wall to make room for a jig to rig a set of biplane aircraft wings. I enjoy challenges and promise I will step up, but it may be a bit.