Spring pole lathe. Why would anyone want to build one?
Well that is the question? Why would anyone at age sixty-three and supposedly in his right mind want to build a springpole lathe and actually use it to turn something? Well there are several obvious answers:
1. Should a nuclear halocaust, extraordinary civil unrest or the arrival of space invaders disrupt the power supply, I could still work on the lathe;
2. I could get a fair amount of low impact, anaerobic excercise while I was turning;
3. I could demonstrate how turning used to be done;
4. I could replicate 16th, 17th, 18th and 19th century furniture and architectural pieces with complete authencity.
Well number 4 was the real deciding factor. But the others certainly came into the decision making process and don’t be fooled, thinking that I was just having some fun with you about number 1….hey, you just never know.
So I began an exhaustive search for all of the information about springpole lathes on the internet. Surprisingly, there’s a lot of information out there.
First, what is a springpole lathe? Well, it’s a reciprocating lathe, meaning that there is a cutting or down stroke and a return stroke. The power for the cutting stroke is furnished by the turner depressing a treadle. The power for the return stroke comes from the “springpole” which has been energized during the cutting stroke. A line is used to connect the treadle and the springpole. Right between the treadle and springpole sits the workpiece, with the slacked line wrapped aroung, waiting to be trimmed to size, so to speak.
Springpole lathes come in all sorts of sizes, shapes and configurations. Just Google any of the words highlighted in the text and you’ll see what I mean. But it’s interesting that the actual technology employed certainly predates recorded history. And springpole lathes were used commercially much more recently than you might think. Bodgers (chair parts makers) took them to the woodlots in England where they turned parts and left the shorts and chips on the forest floor well into the period just before World War II.
Historic re-inactors, restorers and ancient industries devotees are renewing the interest in this simplest of woodworking tools. And, it’s important to note that some of the most ornate and technically challenging turnings ever made were produced before the discovery of electricity on springpole (reciprocal), continuous (treadle & flywheel) or great wheel (turned by your apprentice) lathes. Some of these turnings have never been duplicated on modern power lathes.
Some noteworthy contemporary springpole turners are Peter Follansbee, Don Weber, Roy Underhill, Drew Langsner and Robin Wood. Much more information on springpole lathes is to be found at The Association of Springpole Turners. And for more general history on the art and craft of Woodturning, be sure to visit the Worshipful Company of Turners of London.
Chapter 2 is all about what style of springpole lathe did I want to build? So I set about creating some parameters for my decision making process. First, this was a lathe that I wanted to use in the shop. I had no visions of tramping through the woods with this thing strapped to my back. Second, I wanted to be able to turn 48″ between centers as I invisioned doing some formal bannister back chairs. Third, I wanted enough swing that I could do some bowl turning (after seeing Robin Wood turning bowls at his home in England).
Ultimately, I settled on a design that Roy Underhill has used for a number of years, with a few modifications, of course. The lathe is a double springpole design. This simply means that there is a primary and secondary springpole linked to one another by means of a bridle device. This design offers infinitely variable torque and resistance control. The springpole is linked to an overhead crossarm via a connecting rod (1/4″ hot rolled steel rod). The line connects the crossarm to the treadle.
Roy’s lathe seemed a little small for my purposes. So I set about to build a large, heavier duty unit. Also, it seemed that the work height was quite low. So I designed a lathe with a 20″ swing, 52″ center width and a 44″ working height (at 6’3″ and with a bad back, I need the height). The ways and stretchers were beefed up considerably to create a very stable platform. Lastly, I found that I just wasn’t as lithe as Roy and decided to build a full treadle that would allow me to use either foot at any workpiece position to power the lathe. This has paid huge dividends, although it has caused me to redesign the primary springpole. The original springpole, prior to the addition of the permanent treadle, was 1″ diameter yellow pine. But after the placement of the treadle, it was necessary to go to something stiffer and more durable. Option 1 was to increase the diameter of the springpole which would have been easy enough. But I opted to make a laminated springpole by simply gluing two pieces of hickory together then rounding them on my shavehorse.
MATERIAL OF CONSTRUCTION
For the frame of the lathe I selected Yellow Pine. My northern friends might say why in the world would you choose pine, it’s so soft. Well my friends, yellow pine ain’t soft, no way, no how. Yellow pine was the most popular framing lumber in the eastern half of the US for generations, prior to the advent of the pneumatic nailer. Yellow pine is prone to splitting unless the craftsman takes precautions to prevent the nailed fastner from acting like a wedge, splitting occurs. One only need imagine an enthusiastic young carpenter shooting nail after nail after nail into a YP 2×4 and it becomes clear why beautiful, strong, stable yellow pine has been replaced by “white wood”. In any event YP was available, it was cost effective, strong and, doggone it….that’s what Roy built his lathe from- enough said.The cross arm is white oak (scrap), treadle is ash and YP and, parts of the toolrest are cherry and, as I mention earlier, the springpoles are hickory.
The torque and subsequent energy requirement to operate the lathe are infinitely adjustable due to the variable connection between springpole and crossarm, bridle adjustment between springpoles and extendable treadle arm which allows for increase in rotational stroke.
Another consideration was the toolrest. Due to my height, I tend to work “over center”, a lot. So I wanted a toolrest that would allow for some vertical adjustment. Also I wanted to be able to angle the rest in relationship to the ways. What I came up with was, essentially, a wooden banjo. The toolrest has a steel wear strip. All in all, the banjo and rest work great and I’ve had numerous compliments stating that the rest looks sculpted. Pretty? maybe…but it works and works well.
Centers were simply made from 1/2 x 3 1/2″ carriage bolts, ground to a conical end. Weld nuts and handle nuts were used to support and clamp the centers tight. Both are available from McMaster.
When all is said and done, this is what it’s all about, legs for a joynt stool. But, to those of you who are already proficient turners, making four duplicates of anything on a springpole lathe will test your skill. But make no mistake, you’ll be a better turner for your tribulations.
If you have any more questions about why anyone would want to build and use a springpole lathe, just look at the picture of the guy at the beginning of this post. Is there any question as to why SOCCER (futbol) is the most popular sport in Europe? Just look at that guy’s calves. But then…take a look at that face – is that a happy craftsman?