Saturday, May 22, 2010

Goodfelloes, part 2

Well, the internet is down for a tad so we'll just move along off-line and ya'll can catch up later.

I've been asked, "Can you use dowels for spokes?" The answer is yes, surely. I didn't use them here mostly because I don't care for a perfectly cylindrical spoke from an aesthetic point of view. This illustration from (which was one of the primary inspirations for our wheels) shows cylindrical spokes with the slightest taper.

The Djebjerg wagon also shows nearly cylindrical spokes.

The period wheel would have had a tenon cut on the end (you can see them clearly above) but this can be avoided in a small wagon or cart simply by controlling the depth of the mortises either by drilling or, if you've cut the mortise into the hole for the axle, placing a piece of copper or other pipe in the hole as a bearing.

It's harder to do at the felloe end, and would be best handled, I think, by drilling the mortise slightly deep and then dry fitting and shimming until the spoke "bottoms." Cutting the spoke long and trimming the spoke seems to me to be a more potentially frustrating method. Perhaps you could try using an expanding glue like 'Gorilla Glue,' but, I don't recommend glue on the spokes except as a last resort--fitting them is tricky and adding the extra complication of trying to fit them in within the glue's working time strikes me as a recipe for disaster.

The main problem with cutting the mortises for the spoke felloe tenons is that they must beexactly on the radius.

Here's the jig that let's you do that. (I might add that I wouldn't consider making spoked wheels without having a good drill press handy.) The jig is made from two boards set square (checked and marked with a try-square and screwed: accuracy is critical here) and a cut off from one of the felloes. This picture doesn't show it yet, but after the curved piece is mounted you should roll a piece of pipe so it comes to rest at the very 'bottom dead center' and make a reference mark.

The felloe then gets set in the jig like so:

Let me back up a sec. Normally when you're cutting you make the cut a bit proud of the line and go back and shape later. The felloe pattern should be cut as close as possible to a tight fit on the spokes, and the felloes should be cut as exactly as possible so they fit the jig (and the wheel).

I also see I missed a step with the spokes. (that's one of the problems with going back later from memory and picture files--oh, well...) once the spokes are all set nice and tight in the hub, the hub needs to be mounted in a hub fiddle again. I mounted mine over the table saw, but there are other options.

This has to square to the hub, to saw, to the dado blade, and (according to Thomas Aquinas) the universe. Use clamps. When the saw is fired up the wheel is rotated and the dado blade trims the end of spokes so they are perfectly centered on the axle hole. The hub/spoke assembly is then returned to wheel jig

and a combination square is used to set the distance from the tenon end to the shoulder.

On one tenon I found the shoulder too far from the end (the others all required little or no trimming).

This was fixed by gluing a wood "washer" in place and trimming with a coping saw and shaping with a Dremel to match the decorative cove of the spoke--the repair is unnoticeable.

Okay, back to that felloe we left sitting in the jig. Drill out a mortise deep enough to fit the tenon and go back and dry fit. Oh, yeah, make sure when you marked the felloe you marked which mortise goes to which spoke. Dry fit the felloes to the wheel. When every thing fits together well it's time to glue the felloes together. Some builders recommend a dowel or spline in the joint between felloes for alignment and support. Since this wheel is for such a light weight cart I didn't bother. Instead, I used "Gorilla Glue" which expands into the wood on both sides of a joint, and in the case of pine, makes a joint stronger than the surrounding wood.

I slathered on the glue put waxed paper over the joints, and then used a strap clamp (cargo strap with ratchet) to pull the felloes tight. Then I applied heavy duty spring clamps to the sides so all the joints lined up nice. The waxed paper is to keep the squeezed out glue from gluing the strap and clamps to the wheel.

When all the glue is dry I popped the wheel in the workmate bench (a wonderfully useful tool) and sanded everything up nice and smooth.

If you look back to the first picture you see that between the spokes the wheel has been carved away a bit. This serves absolutely no function, but it is pretty.

After using a 1/2" round over bit and router to shaped the outer edge of the wheels I grabbed a plastic container I had lying around and marked the sides of the felloes to replicate the decorative cove. I cut these with a 45 deg. bit in a rotozip starting it as a climbing cut (with the grain) by eye. You need to be a little practiced at this or you risk the bit jerking you along and buggering up the cut, but the rotozip is a handy tool for this sort of thing.

Voila! Time to step back and admire your handiwork. Let me mention again that making spoked wheels is a lengthy, finicky, tedious, irritating process. From the description here it sounds like you only dry fit a few times, in reality it's over and over and over and over. I respect anyone who goes to the trouble of making spoked wheels, but truly, for most SCA uses I wouldn't bother. Though another nifty aspect is that once you've made all these jigs later wheels are easier, and you can make spinning wheels, too. (Fionnseach and I are working on one for a Creative Anachronist, to be blogged down the road).

Lastly, this is not a wheel, it's my first try at a loaf of rye bread with caraway, Yum!


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