Archive for February, 2010

Treadle Lathe – Makin’ Parts

Thursday, February 25th, 2010

Overnight temperatures in the workshop are slowly rising toward the minimum needed for epoxy work. Spring might be coming. Song birds are returning their joy to the neighborhood. Boy are those babies getting a surprise today. We have 12-18 inches of crystalline global warming falling from the skies today and tomorrow. So, work continues on the treadle lathe.

When I was making the flywheel, I doubted the ability of my trusty turning saw to do a good job with the wheel’s thick stock. I wimped out and used the bandsaw to ensure a round wheel. Wanting ogee curves on the tops of the headstock and tailstock posts, I decided to give the turning saw a try. These posts are the same thickness as the wheel. The only difference between these cuts and the wheel was the level of perfection needed. It turns out that the saw, using the 10 TPI 1/8″ Gramercy blade, acquitted itself quite well.

On a piece of cardboard carton (empty pasta box) I drew a curve that pleased me. I traced around that to position the pattern on both sides of all three of the parts. Sawing close to the line was not at all difficult. Yes, it was slow going but cost only a couple of Milky Way bars. A Nicholson 2nd cut cabinetmaker’s rasp was my tool of choice for completing the shaping.

Boatbuilders often use beading to dress up the plain parts of small boats, usually the thwarts. The beading shows good craftsmanship and also eases the comfort of bare legs sitting on the thwarts. Stephen Shepherd recommended beading in his lathe bench plan notes. So, I want to use beading on some of the parts. Having never done it, I researched (of course), and determined a scratch stock is the tool of choice for such work. More research found me many ways of building a scratch stock tool. I ended up eliminating all but two, a design by Tom Casper in the October 1999 issue of American Woodworker (a bunch of them online thanks to Google Books), and a design by our beloved Village Carpenter, Kari Hultman.

As much as I like the simplicity of Kari’s approach, I thought the design with two reference surfaces would be easier to control. I made it from a bit of Ash. The basic “L” shape was cut first. Then, I fitted the screws, removed them, and resawed the tool into two pieces. Rounding the long fence face, and rounding over all the other edges completed the stock. The scratch blade is a bit of saw blade cut to a small square and then filed with a rattail file.

It works surprisingly well. It’s a good way to improve the appearance of this marginally acceptable lumber. Now, the real reason for beading is to strengthen the part. A piece of lumber with sharp square edges is subject to splintering as it transitions through humidity changes. Splintering leads to splitting. Splitting leads to twisting and warping. Knocking off the sharp square edge significantly lessens the potential for splintering and all the rest. Hence, strengthening the piece, while making it more attractive.

Treadle Lathe – Plans and Lams

Tuesday, February 23rd, 2010

The last 15 years of my previous career were spent in the world’s finest commercial research laboratory. From there, I learned a method of working that leads me to do a good bit of research at the start of a project, to learn a great amount about a subject before starting the actual work. I continue that practice with my woodworking projects, often collecting many more plans and articles than one could ever use, and then building to none of them.

Plans

My first article about building a lathe touched quickly on the sources of a few plans for lathes. By “plans,” I mean publications that include measured drawings or enough detail to be useful as construction guides. Here are a few more details along with some of my opinions.

  • Roy Underhill’s treadle lathe article describes a lathe built from discarded lumber salvaged from the dumpster outside a university dorm. This article comes to us compliments of the Woodworking magazine blog, originally published in the October 200 issue of Popular Woodworking magazine. Underhill’s usual humor augments the constructon details for a lathe is smaller and lighter than the one Roy often demonstrates on Woodwrights Shop TV program. It fits very well with the idea of using standard size construction lumber and has a number of features that simplify construction, such as connecting the pittman arm directly to the flywheel instead of fabricating a metal crank. While a nice feature, it requires the flywheel be cantilevered, and I wonder about the durability of such an arrangement. An appealing added feature is a lightweight scroll saw attachment. I definitely want to use this idea, but will build one a lot more robust.
    All in all, this is a fine article with a very complete cut list, good instructions, and a bit of Roy’s humor. It strikes me as a fine “starter” treadle lathe. There’s also a Sketchup model here.
  • Steve Schmeck keeps a website covering a variety of topics, many of them environmentalist in nature. His lathe plans have been available for several years. Steve’s lathe is quite a bit like the pictures published in the first of these lathe articles, substantial in size, but still manageable for transport in his van. It lacks the diagonal braces shown on some designs. An added feature of Steve’s lathe is an optional tension adjuster that alleviates the chore of resewing a stretched drive belt. Like all of the lathes I considered, construction is from construction grade lumber with hardwood mixed in where you think appropriate.
    Since Steve’s plans are in a book (eBook(pdf) or CD) that need be ordered, you can see a few pictures without buying at a page where Steve shows a few lathes built from the book’s plans.
    You bike riders might want to check out Steve’s homebuilt “Woody” recumbent bike. Yep, a wooden bike.
  • Mike Adam’s lathe is somewhat similar in size and construction to Steve Schmeck’s. He does the various bearings and the crank a bit differently, housing bearings in hardwood inserts. His foot pedal is a full width frame, not just a single board as in the previous designs. Being a bit klutzy, this wider pedal holds appeal for me. Mike’s spoked wheel looks great, but he admits it was too difficult to construct and needed additional balancing once done. That’s why I decide on a solid wheel. Mike posted a YouTube video showing it in action.
  • Followers of Stephen Shepard’s Full Chisel blog will recognize Stephen as a restoration specialist and expert artisan for nineteenth century woodworking (from the turn of the century until “the unpleasantness between the states”). Stephen’s plans are available from Joel Moskowitz’s excellent Tools for For Working Wood store. You’ll find Stephen’s plans here. True to form, Stephen’s plans are excellent, drawn from an 1805 exemplar. They are very complete, comprising eight 11″ by 17″ plates and 4 pages of commentary. This lathe is distinctly different from the others, being a combination lathe and workbench. The wheel is more forward, pivoting from within the headstock uprights instead of from diagonal braces further back as in all the other designs. A bench surface extends rearward for 12 inches beyond the spindle centerline and is the full width of the lathe. A small vise attaches to the back edge of the bench. It is a clever design for those pressed for space. Also interesting are the several purpose built, hand wrought, chucks. They appeal, but will require finding a blacksmith.
  • Lastly, I referred to web material by Howard Ruttan. His is, alas, not a set of plans, but a comprehensive FAQ with yet more links to research.

Lams

Many of the lathe components need to be thicker than typical construction lumber. Thus, we laminate. My nearby home center stocks the usual number 2 lumber that’s useful for framing. Like most of this stuff, the narrower pieces are the worst available, often being milled from trees barely large enough to contain a single 2×4. I buy much wider boards and rip them to the widths I want. One good feature of most of their lumber is that it is reasonably dry and does not need a lot of acclimation. The lamination process is simple. It consists of these steps:

  • Plane the intended faying surface enough to ensure a good join. This is most useful to remove cupping; planing only the faces that will join each other. The jointer plane is your friend here.
  • Rip.
  • Glue and clamp (currently using yellow carpenters glue). When laminating, ensure stability by having the outer edges of the board, the edges toward the bark, face each other. The end grain should look like this: )))(((
  • Plane off the crowned edges (if any), using first a scrub (#40) and then a jack (#5).
  • Remove most of the surface uglies with a smoother (#4).

Effort and energy cost: about one Snickers bar per 10 foot lamination.

Treadle Lathe – the Wheel

Friday, February 19th, 2010

The one point of agreement in the many plans I’ve collected is having a flywheel of 24 inch diameter. Construction varies with the different plans, some with interesting spokes and rims, some solid. I chose solid: easy. I like easy. It wants to be a substantial wheel, the heavier the better. Two layers of 2-by lumber would do it. However, that would leave a seam in the middle of the wheel. What if I decide to drive it with a cord rather than a flat belt. Wouldn’t that seam invite trouble as a gutter is routed for the cord? To avoid that eventuality, I used 2-by material for a middle layer, and then attached 1-by material on either side. Yellow carpenter’s glue and a bunch of countersunk screws bring the layers together, each offset by 60 degrees.

Now, let’s make it round. I really really really like doing as much as possible with hand tools. I have a great turning saw that uses Gramercy blades. However, this wheel presents 3 problems. First, the coarsest Gramercy blade is 10 TPI and 1/8 inch wide. That seems a bit skimpy for this cut. I would prefer 6-8 TPI and 1/4 inch wide, a size not available. Second, a wheel really needs to be round with a nicely perpendicular edge, something I imagined hard to achieve by hand. Third, I don’t have enough Snickers bars on hand to power that much sawing.

So, it’s time to dust off the band saw … and extend its table. It didn’t take much to knock together a one-time use table extension that has a pivot hole 12 inches from the blade. It took longer to find the screws than to make the extension. The table on this Rigid saw has holes tapped for 6mm by 16 screws. How many of you can find 4 of those in your loose parts collection? I did. :)

There it is, a simple wheel. It weighs 24 pounds. I don’t know if that is heavy enough.

Oh, before I quit, let me show you one very sweet hand drill bit. I learned from my fellow galoots over at the Saw Mill Creek forums that it might be a Cook (US patent) or Gedge (UK patent) pattern. Most of the hand drill bits we see these days are either Russel Jennings or Irwins, with spurs pointing toward the tip. This bit has the spurs turned back toward the shank. It makes a very easy entry, and better yet makes a very clean exit. There’s no tearout at the exit; no need to stop before exiting and drill back from the other side. It seems that Ransom Cook patented this pattern a few weeks before Jennings, but maybe didn’t have as good a marketing department. The Jennings bits prevailed.

Chasing another of the patent references made by Jeff in the forums, I see a patent by James Swan, some 20 years after Cook’s. Swan’s improvment was to extend the cutting edge from out at the curl all the way into the screw. My bit is indeed a Swan. This one came to me as one of a handful of odd bits that Patrick Leach threw in the box when I bought the Stanley brace. It’s the only one of that pattern I have. After using it, I’m wanting more.

You’re Gonna Build a What?

Wednesday, February 17th, 2010

Preserving history at the Kansas City Renaissance Festival

A lathe, my dearest, an ole time treadle lathe.

Re-enacting at Fort Osage Missouri

We looked at some pictures a while. She said “Sure, get to it … but, if you show up in one of those costumes…”

These top two photos are thanks to Jerry who preserves history by working with the Institute for Historic and Educational Arts in Kansas City. THANKS Jerry! (As always, click a small picture to see a larger version.)

It’s still too cold in the shop for epoxy based boat building, and another 5 inches of “global warming” just fell today, I’ve been considering two other woodworking paths.

Beautiful old clocks (or replicas), complete with mechanical movements, are things I have built in the past and have considered for the future. Previous clocks were built from kits. I would like future cases to be built from scratch. I fancy clocks such as regulator wall clocks, and Vienna Regulators. As near as I can tell, some of those would require a half set of hollows and rounds, a plow plane, and maybe a pair of snipe bill planes. The wait queue at Clark & Williams, as well as the cost, make that path one that won’t be taken this winter.

So, let’s pursue the alternative, the lathe. Why a human powered lathe?

  1. Because I like human powered things, hand-tool woodworking and paddle powered boats, for example. Treadle powered tools have always caught my attention, and now I have time for them. In short, I see a treadle lathe as a neat machine.
  2. There’s no shortage of turned things I find interesting: mallets, tool handles, more tool handles, toys, lidded boxes, chairs (not Windsors), and exquisite wooden bowls. I’m not interested in pens or bottle stoppers.
  3. The lathe will also be the power base for a scroll saw. I have some very interesting scroll projects in mind.

To which design or plan? Choices, choices, lots of choices on the internet. I collected several comprehensive plans (Roy Underhill’s, Steve Schmeck’s, Mike Adams’ and Howard Ruttan’s), and plenty of pictures. All have great merit, and I will build not to one specific plan, but will take bits from here and there. From Roy’s, I will take the concept of the scroll saw. His lathe has one aspect I didn’t care for, an inboard flywheel. It was also skimpier that the lathe he uses on his TV Programs. Mike’s and Steve’s are more robust and have flywheels held between two uprights, not cantilevered like Roy’s. I like the full width treadle of Mike’s, and actually a sturdier one like in the Ft. Osage picture at the top. Guidance for bearings, various shafts, and centers come in bits and pieces from all of the plans and from an email exchange with Jerry.

The attractive feature (to me) is that any of the above designs can be made from readily available “Nbr 2″ construction grade SPF (SprucePineFir) lumber. The big orange store up the road has some fairly good Doug Fir that I’ll use for most of it. Some Ash or Oak will fill certain roles.

Oh, for those who like the idea of a treadle lathe but would rather not build one, Chris Yonker makes beautiful lathes and sells them through his CME Handworks eBay store.

OK. It’s time to get to it.

UPDATE: When I wrote this entry this morning, I was getting a 404 error when trying to reach Mike Adams’ TreadleLathePlans site. That site is still not responding, but I have found an alternate source for his plans.

UPDATE 2: Stephen Shepard suggested (in the comments) another set of plans that I had overlooked. They are Stephen’s own plans which are sold by Joel Moskowitz’s excellent Tools for For Working Wood store. You’ll find Stephen’s plans here.  TFWW always ships very fast and I live close enough to expect receipt in the next day or two. Thanks Stephen.

Andre Roubo’s Try Square

Thursday, February 4th, 2010

The workshop is still too cool for epoxy work, keeping the boat building project on hold.

Waste not; want not. After making the winding sticks, the left over madrone was crying out to be used, not wanting to linger or be relegated to the cart (1:02). I imagined enough left in that remnant to make a try square. No, I don’t build large squarish things (yet), but I do appreciate shopmade tools, and know that someday I will want a try square a bit longer than the metal 12 incher.

Lessee now, haven’t I seen articles about try squares recently? It’s not that I really wanted detailed plans, but a few hints and tips would help. Oh yeah, “the Schwarz” wrote something a couple of weeks ago. By remarkable coincidence, the very day I went looking for articles was the day that the Popular Woodworking magazine published Chris Schwarz’s article and plans for Andre Roubo’s Try Square. It’s a fine article, and the dimensions came close to finding themselves inside my left over piece of madrone. I adjusted sizes to the material on hand and got started by reserving a 10 1/2 inch length for the stock and using the remainder for the blade, which turned out almost 20 inches long. The stock was ripped to width, and the remaining  3/4 inch material was handily resawn with my frame saw. Planing the blade down to 1/4 inch thickness was only a few minutes work. That prepares the raw materials. There’s only one small problem. Schwarz’s article highly recommends making layout tools from quartersawn hardwood (“is a must”), and specifically beech. My madrone was neither. But, it had two other attributes that made it suitable: it was on hand, and it was paid for. I think its stability will be OK. This piece has been acclimated for a couple of years.

Schwarz says, “There’s only one joint in this project and you need to make it perfect.” Well, that’s a fine way to make me throw down the article, walk out of the shop and go for a Snickers bar, or something stronger and more soothing. Perfect!? Gheesh! After that proclamation, Schwarz wanders off into Norm-land describing how to make the cut for the bridle joint using jigs, dado stacks and a table saw. None of those things around here. Time for another Snickers bar.

Shucks! I’m a boat builder, not a furniture maker. I haven’t yet bought any sophisticated saws, no tenon saws, no dovetail saws, no backsaws of any kind. I can do that joint without any of those fancy saws. My cheap Stanley toolbox saw is still kink free and cuts relatively straight. I’ll just color carefully inside the lines and if it doesn’t work out, blame it on the lumber not being vertical grain beech. The toolbox saw and some careful chisel paring made a bridle joint that is a small distance from perfect, but is a very much closer than I originally imagined. It is further proof that “We don’t Need No Stinkin’ Backsaws.”

The rest of the work roughly followed the advice from the article and the square went together nicely. It is also square, after very minor truing. I added one feature that I saw Chris write about sometime ago. A 1/4″ dowel resides in a hole toward the end of the stock. Slide that dowel out a bit to help hold the stock on the workpiece being marked. It keeps the square from flopping over just when you don’t expect it. Finish is the usual, a couple of coats of BLO. The picture shows the square with the first coat, showing the richness of this nice little piece of wood.