Spiffing up your Campsite...
Spiffing up your Campsite....
By Ld. Chas. Oakley, Esq.
A 16th Century German Wheelbarrow
So, let's say you're camping at Pennsic and your land-o-crat got out there really late and that spiffy campsite you've had the past couple of years got given to this group who style themselves as time traveling Klingons while you and your friends are stuck out in a campsite that has an Ohio zip code. You need ice. You need to get your armor to the battlefield AND BACK... What do you do?
Well, thanks to those industrious and clever German folk there is a solution to your problem. Why not build a wheelbarrow?? Takes too much space in your wagon you say... Not this one. Except for the wheel/axle assembly the whole thing comes apart and lies flat. Its almost like it was designed for SCA use...
What its all about:
(Information and illustrations found in Georgius Agricola's De Re Metallica; Translated by Herbert Clark Hoover and Lou Henry Hoover, 1950, Dover Publications, New York, New York. Translation is from the first Latin edition of 1556):
"That which we call a cistum is a vehicle with one wheel, not with two, such as horses draw. When filled with excavated material it is pushed by a workman out of tunnels or sheds. It is made as follows: two planks are chosen about five feet long, one foot wide and two digits thick; of each of these the lower side is cut away at the front for a length of one foot, and at the back for a length of two feet, while the middle is left whole. Then in the front parts are bored circular holes, in order that the ends of the axle may revolve in them. The intermediate parts of the planks are perforated twice near the bottom, so as to receive the heads of two little cleats on which the planks are fixed; and they are also perforated in the middle, so as to receive the heads of the two end boards, while keys fixed in these projecting heads strengthen the whole structure. The handles are made out the extreme ends of the long planks, and they are turned downward at the ends that they may be grasped more firmly in the hands. The small wheel, of which there is only one, neither has a nave nor does it revolve around the axle, but turns with it. From the felloe, which the Greeks called -------, two transverse spokes fixed into it pass through the middle of the axle toward the opposite felloe; the axle is square, with the exception of the ends, each of which is rounded so as to turn in the opening. A workman draws out this barrow full of earth and rock and draws it back empty."
The lead illustration shows a wheelbarrow that I build based on the above description. Included in it is a drawing of the cistum as provided in the original book. I am pleased to say that, at Pennsic 27, I used this wheelbarrow for two weeks... it was wonderful.
Some notes on construction:
Although it would be possible to give a set of plans that spelled out in detail all of the measures and sizes needed to build a wheelbarrow, in this case I think, it is more important for the builder to grasp some of the engineering considerations involved in the construction of the wheelbarrow and modify the plans in such a way as to make the barrow the most suitable for them. Therefore, while dimensions are given in most areas, I would encourage anyone who desires to build one of these to read the plans and then make such modifications as necessary to these plans so that the wheelbarrow will "fit" them.
The prototype wheelbarrow I built and that is shown in the first illustration contained in these plans had several "flaws"... none of which made it unusable but which did limit its utility a bit. The two most noticeable flaws were these:
In addition to the above "corrections", I would also make the following observation. While the description given in the beginning of this article talks about a wheel built with four spokes, all of the illustrations in De Re Metallica clearly show wheels built with six or eight spokes. The purpose of this is obvious, strength. The more spokes a wheel contains the greater its strength. Yet, for all practical purposes, four spokes are for most purposes sufficient. I have carried loads in excess of 240 lbs. in my barrow and, while it was heavy and a bit awkward to handle, it didn't appear to put the wheel under any undue strain.
The following plan shows a general plan for the construction of the side boards of the wheel barrow. Again, you can build from the dimensions given... or you can make stylistic modifications to your taste, size, etc. When laying out the mortises for the bottom board of the wheelbarrow (those at the bottom edge of the side), make sure to leave at least ˝ of an inch of material below the mortise. This should be sufficient to support whatever load you might carry.
The illustration to the right shows a profile view of the wheel used on my wheelbarrow. Inspection of this illustration shows that the wheel is composed of nine parts. There is a single axle assembly, four spokes and four "felloes" or sections to the wheel itself.
One of the most important things about building the wheel is to pay attention to the direction of the grain of the wood. As you can see from the illustration, the grain should run perpendicularly to the spoke. By using the grain in this manner, no "shear faces" are presented to load that might make the wheel fail under strain. In addition, when we get to the construction of the wheel you'll see how the lap joints that are employed are strengthened by the crossing of the grains at the joint.
The next illustration shows the construction of the axle assembly. The axle is made from a single piece of oak stock. I turned the axle ends on a lathe but careful work with a rasp and chisel can accomplish similar results.
The axle is a pretty straight forward construction. If you examine the above illustration you'll see that the axle is cut to maximum width (outside width) of the wheelbarrow. The rounded ends of the axle are (on mine) 1.25" in diameter and 1 ˝" from face to shoulder. This depth is the equivalent of the width of the material used for the side of the wheelbarrow. The shoulder is a cut that ensures that the axle stays between the sides of the wheelbarrow and let the axle turn properly. The taper is purely aesthetic and serves no practical purpose... On each face centered along the length and the width of the axle is a 1" diameter hole bored about 3/4" deep. These holes will receive the spokes of the wheel that will be glued into them.
The illustration to the left is a diagram on the formation of a "felloe" as I built them. There are a number of different methods for joining the felloes. Some are assembled using doweled mortise and tenon joints. I used glued lap joints and found that, properly constructed, they will provide all the strength necessary.
If you examine the illustration you’ll see that a felloe is a piece of wood that covers a 110 degree arc. Each shoulder (for the lap joint) covers 20 degrees of arc.
To make the felloe, get some nice 2" material and, using a compass set to the diameter you elect to use for your wheel, scribe an arc on the wood. Draw the lines that will define the ends of the felloe (the 110 degree arc) from the center point to the outer rim of the felloe. Draw in, on one side a line 20 degrees from the left end to mark where the shoulder for the lap will go. Don't try to mark the other side yet. Now, cut out the felloe.
After the felloe has been cut out, draw a line on the reverse side of the piece that will identify where the other shoulder will be located (again, a line 20 degrees to the right of the left edge.
Place the felloe in a drill press and drill a 1" hole, centered on the interior face of the felloe, to a depth of about 3/$" deep. Then, using a hand saw (or router if you want to use the speedy method), remove EXACTLY ˝ of the thickness of the material from each shoulder line to closest edge on each side of the felloe.
Repeat this process 4 times.
Fit the wheel assembly together and measure the interior diameter of the wheel. Measure the diameter (side to side) of the finished axle. Subtract the diameter of the axle from the interior diameter of the wheel. Divide by 2... add 1˝ inches. This should be the length of each spoke. Cut four spokes to this length from 1 inch doweling.
Assembly of the Wheel: At this point you will need a fair number of clamps. 4 is the minimum. Apply glue to the faces and interior of each shoulder cut. Put two felloes together and clamp. Glue spokes into the holes of the two assmebled felloes and the axle. Continue to glue up felloe/spoke/axle... clamping as you go, until the wheel is finished. Let the whole mess set for at least 24 hours before removing the clamps. NOTE: This structure is the primary weight bearing structure of the wheelbarrow. Doing quality work here will have a great deal to do with the overall success of the project.
The next step: There are still three pieces to cut out. These are the bottom board and two end boards. The illustration to the right shows the basic shape of each type of board. Again, the exact size of these boards will depend on the dimensions you choose to use for your wheel barrow. Some general notes on their construction can, however, be offered.
First, the mortises on these boards should be constructed such that the inside of the mortise (that edge closest to the sides of the wheelbarrow) should extend under the side board to a depth of about ˝ of an inch. This will allow for "drawing room" when you drive home a wedge.
Secondly, the outside edge of each mortise should be tapered to match the taper of the wedge you will be using. This will help to avoid "tear out" of the mortise after repeated installation and removal of the wedges.
Third. Don't make the fit of your mortise and tenon joints too tight! Remember that wood swells and if you want to take the wheelbarrow apart after a rainy day a little slack in the joint will be your friend. You shouldn’t make a "sloppy" joint either... something "finger tight" will suffice. The wedges will draw the joints up tight.
Fourth... when making the pieces, remember that you are the endboards are angled. Transfer this angle to a guage or a piece of paper. You can use it for "dressing up" the front and back edges of the bottom board and the top and bottom edges of the end boards. Study the placement of the end boards and the bottom board in the illustration of the wheelbarrow's side boards near the beginning of this article.
Fifth... Although all of the illustrations in De Re Metallica show wheelbarrows with iron bands holding the bottom board to the sides, a 16th century alterpiece from Annaberg in Saxony that is shown in The Age of Chivalry (A volume in the National Geographic Society's Story of Man Library, 1969; page 354) clearly shows a barrow constructed in the manner set forth in this article.
Sixth. You may want to nail a strip of iron (1/16th or so thick and the width of your wheel) to the wheel's face. The drawings in De Re Metallica suggest such fixtures although nothing is specifically mentioned. It is a logical extension to the plans and will save a lot of wear and tear on the wheel's surface.
Cut out 6 wedges to fit the mortises and... well, basically that's it. Put a little grease on the axle ends and assemble it. You may want to take a spoke shave and relive the under side of the handles a bit... that can save some wear and tear on your hands... but that is all the embellishment I've noted on the wheelbarrows...
Have fun... make stuff...
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