Re: [MedievalSawdust] Cart
- Ah. Now we see why there were so many different types of craftsmen long ago - then again, I understand that each style of new car takes different tools just for a tune-up....no more shade-tree mechanic. I imagine that you would have to build a couple of dozen carts to really "get it down to a science" as far as how much wood, the cuts that give the best yeild, etc. About the only thing that I really "know" about carts and wheels (and I was surprised to learn this) is: a wheelwright doesn't make the rim of the wheel on the same plane as the hub. It forms a sort of cone-shape with the hub close to the cart and the rim away. It has something to do with stress, support, and making turns, but you'd have to talk to someone who has really studied it to find out the engineering logic of it.
thorolfr@... wrote:A whole lot of TLAR. (That looks about right) ;)
I wanted to make a wheel, but I didn't want to invest huge sums of money in an experiment, hence the 2x4 construction. I used 12 felloes because that gave me and efficient use of the width of a 2x4. Did I mention that 2x4s are fairly cheap? ;)
The first time around (you can see it in earlier pictures) I used 6 spokes made from 2x2 connected by 1/2" dowels to a hub made by a section of 2x6 shaped into a hexagon. In the first version of the cart the axle was a piece of black iron pipe connected to the wheels by a floor flange. However, this meant that the wheels did not turn independently of each other. So when an enthusiastic young lad (not me) was giving a lady a ride in my cart he turned too quickly/forefully and it ended up tearing out the hub. Ah well. I tried rebuilding it using the bar from a barbell and increasing the thickness of the hub to three pieces of 2x6 but the 2x2 spokes failed again. Ah well.
I recently came into possession of a quantity of 1 inch thick(literal) oak boards from which I have remade the spokes. The current spokes are two inches wide at the centre and taper to one inch wide at the felloe where they form a one inch round tenon into the felloe. The centre portion tapers in the other plane to the centre. This can be better seen at http://tinyurl. com/2uzo5r The centre is reinforced by two six inch round discs which hold the centre in place with six bolts.
The bed of the cart is made from a couple of pieces of flakeboard I happened to have lying around the shop and the sides are made from some hardwood boards from a couple of skids I was able to get from a metal manufacturing plant.
Its not yet been fully tested under final loads. Plus I am going to shape the ends of the handles to a more comfortable shape. I had originally used 2x2s for the handles but when the cart failed for the second time the handles snapped through the finger joining on them.
Its been a lot of fun learning a lot about wheels and carts. :) Assuming it survives its first real test at the next event, I plan to bring the cart to Pennsic should any care to see it in person. If we get the same block we had last year and if we get the same position on the block we should be camping immediately below the runestone in the Eoforwic encampment.
A friend of mine has made a breakdown wheel barrow which can be seen at:
-ThorolfrWhen you get down to it about all a man has to call his own is his values. When you sell those out, you don't have anything left.Col Sherman Potter4077 MASH
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