Heritage - News
Compagnes Drift MillUpdate for 14th August 2009
Update for beginning of June 2009
Horse, Hopper and Shoe
Again, working from the one poor picture out of James Walton's book of the now derelict Kleine Zand Drift Mill in Bredasdorp:
On a check list, Tun, done! Lid for Tun, done! Next is the 'horse' or support for the rest of the furniture, the shoe, hopper and the guide for the top of the damsel. In this picture the 'horse' is made out of two tees, fixed to the tun, diametrically opposite one another. Unfortunately the diagonal beam obscures the bottom of the front tee, but it must be fixed to the tun, otherwise it would be standing in the meal-spout!
Having started with the wood from the old spray tank, I wanted to continue with it as far as possible. It will be good to say that only this wood has been used in the 'furniture', and that all the wood has been used up! My woodworking equipment is confined to a radial arm saw, sander, router and a drill press, so I felt I needed some help with the tees. Once again, Abie at Somerset Timbers was most helpful and quickly ran six of the planks through a thicknesser, to make sections of about 50 X 32mm. He then glued them in pairs, almost invisibly, to form 50 X 64mm sections. One of these he cut carefully in two, making decorative ends (partly to save as much length as possible!) and then tenoned a joint on each, to join the crossbars thus made to the uprights, which he left at full length. Instructions:
And finished objects:
I popped in at the Mill with them in the week and offered them up to get the same proportions as the picture at the top, and marked where I should cut the legs off, just above one of the steel bands on the tun. One offcut I sliced down the middle to serve as spacers between the legs of the tees and the tun, so the lid which overlaps slightly, can be removed.
Again, looking at the picture at the top, there are two longways fore-and-aft supports for the hopper, which appear to lie in grooves cut in the top beams of the tees. Abie prepared two more of the old planks for this purpose, but how wide should they be spaced? This depends on the hopper, it seems. So making the hopper had to be the next stage. Ever made a hopper? I haven't, certainly not in wood! I'd seen the one at Boskloof recently, which gave me ideas, and naturally there are the hoppers on the Stamford and the Gutmann to study. But I still want it to look like Kleine Zand Drift!
I've completely forgotten anything I ever learned about 'Developments and Abutments'; the study of making flat drawings out of a (normally sheet metal) object and vice versa. Angles and shapes on flat paper take on totally different perspectives when assembled! So I started with some board, marking and cutting:
Out of this and more hardboard, came this:
No good, I'm afraid, too 'flat' an angle, the grain would be reluctant to flow. The experts say grain must have 45 degrees or steeper, if it's not agitated, to flow. I pulled it apart again, and trimmed off the outer edges and came up with this:
Much better! Now for the wooden joining strips inside the corners, without which, I knew I wouldn't be able to make up the hopper. The angle inside the corner isn't 90 degrees, it's a much flatter angle, and so I cut some square sections and experimented with different angles of the saw blade until I had it as accurately as possible in my mock-up:
Looks easy? It wasn't! No doubt it would be to somebody doing this work all day! But then what? How on earth to make up the rest of the hopper? How to support it while assembling it? All these questions are easy when working with metal; with this, one bump and the whole mock-up collapsed! Often!
The material I'm using is the remainder of the wood from the spray machine tank which Abie slit longways and thicknessed, all different widths, and not too much of it, considering there was a hopper, a shoe and possibly a meal spout to make out of it:
I set the saw blade at all kinds of angles and tilts and eventually I could attach one top plank to one of the corner strips. Then another as the first and I could join those two, one overlapping the other at the corner:
Not using glue at this stage, rather brass screws, two at each end of each plank. Detail of a corner:
Then a third, then the fourth, which did need a bit of force to join up, my angles weren't all that accurate!
Not looking too much different from the mock-up in the background! I trimmed the 'top' ends of the corner strips and put it down on the floor, big side down, and started planking. Second strip:
I'm using any width of plank, just to use them up with as little offcut as possible, but once sanded and painted, I think it will look good! When the screws ran out (50 so far!) it looked like this:
Friday evening, with 80 more screws, I carried on planking, ever upwards towards the small end, again selecting planks for the least offcut. The ends of the planks which overlap at the corner were all cut just a bit too long, to sand off at the end. I stopped planking when the hole was as small as I think it needs to be:
Then I simply used the belt sander to square the 'mouth' off. Once that was done, I sanded the edges sticking out and then the whole outer and inner surfaces, then used wood stopping to fill the screw holes:
I hope it's going to look as 'old' as the rest of the 'furniture'! Next, I needed to know whether I could make the slots in the tops of the tees for the longways supports, so that the hopper would lie between then like in the picture I was copying from. So I set up one tee in the tripod vice, making sure I didn't get vice or clamp marks on the wood. The other I clamped to a block on the saw table. Then I levelled and squared the two tees up with one another and clamped two strips of wood to the tops of the tees, and then rested the hopper between them:
Right first time, I think, and the slots won't be too close to the ends of the tees, nor yet too far. Now to make the slots for the longways bearers..... The tees were too tall to use the radial arm saw, so that left a hand saw and chisel (I'm not good in that line!) or perhaps the router. With a guide clamped to the tee, I found I could make an accurate groove, square and exactly to my mark, the trouble is the cutter I have is very blunt, so I stopped in the hope of finding a router bit like a slot drill that we use in a milling machine.
Saturday morning at the Mill, first job was to sand the wood-stopping down and to give the hopper a couple of coats of the same varnish, Woodoc 50, with Rosewood colouring.
I'd managed to get a slot-drill type of cutter for the router on the way, so that was the next move, the cutaways which the longways support beams will lie in:
The plank on top guides the foot plate of the router, the one at the bottom protects the wood from a nasty mark; the underside of the tee will be very visible from downstairs! Next, I cut and screwed two spacer planks to the legs of the tees with a gap in between for the steel band and after a quick coat of varnish, offered the first up and drilled a hole through leg and tun for the bottom bolt.
I didn't want to do the top hole until the tun was in place; first I'll put a spirit level across the top of the tee. However, the bottom bolt had to be inserted from inside before the tun could be lifted into place over the stones. A visitor was rash enough to appear just as I needed a hand to do that! But first I used a vacuum cleaner to remove anything around the circumference of the bedstone.
A momentous occasion! Then the two longways planks could be tested. They just cleared under the beams for the crane, which can now be removed:
The spacers between the tee legs and the tun aren't thick enough yet for the lid of the tun to clear, so I couldn't cut the corresponding slots in the planks. They will drop into and over the slots I'd just made. Nor could I put the hopper in place; that would have been fun!
Now most things were in place to do some more trial milling. I let water over the wheel and the first problem struck me, how could I 'feel' when the stones were set correctly? I 'conditioned' some grain and tried it out, water wheel running at 8 RPM, shaking grain into the eye by hand with a scoop and with a makeshift meal-spout made of a cardboard box for light bulbs!
At first it wasn't right, the stones were too far apart, but after some experimentation, I got the 'feel' of the stones, and marked the tentering wheel at the right spot. We had a celebratory drink with Jayne and Wesley, the unwary visitor! Although some meal came out, it was clear that a lot was staying behind. I shut down and lifted the tun a little all round and scooped the meal out with the 'food only' dustpan-and-brush.
I put it through the sieve and bearing in mind the time it ran before I got the stones set right, I was very pleased with what went through the mesh:
Would you eat bread made from this? I will! I held back what didn't go through the sieve to experiment with next time. But one thing's for certain, we need a 'sweeper' on the runner stone! The next job was to clean up, something I've been considering for a long time. In the week I made up this makeshift vacuum cleaner, which discharges directly out of the window:
It's the air pump from an old Vorwerk vacuum cleaner found on a rubbish dump, two drops of oil on the bearings and a bracket holding it in place made from an old generator cradle. The clear reinforced hose comes from our shop.
I did some careful measurements for the shoe, damsel and meal spout before leaving.
Breakfast on Sunday included bread made from Saturday's meal! No ill effects and it rose well, indicating lots of gluten surface available for the yeast to work on, meaning there's lots of fine stuff!
I had brought the two tees home; according to the measurements I took on Saturday, I could make and fit the support for the back of the shoe. I have since found a poor photograph in Walton's book of the shoe at Kleine Zand Drift, and although it's difficult to make it out, he says the shoe issupported on the rear upright of the 'horse'. It also shows that there was a leather 'funnel' or sock attached to the end of the shoe, which I was suspecting would be necessary, as the outlet of the shoe is a long way up from the eye of the runner stone. We have seen similar socks at Boskloof and Kabida.
I then cut and attached the extra spacers to the uprights of the tees, so the uprights would clear the lid of the tun. I might still sand these at a slight angle so that the uprights are vertical against the sloping side of the tun:
Then it was out with a pencil and paper to try to work the shoe out. I'm not sure whether it will work, but this is what it looks like:
The big lump on the left is the 'rap' which the 'damsel' hits as it rotates, shaking the shoe. I realise that the Gutmann's one is on the right hand side so the action of the damsel is away from the hinge. Here, because the runner rotates the other way, I've got it on the other side. There's still a lot of wood to remove where the sock will be attached. There's a dot at the end of the middle plank which should represent the centre line of the millstones and therefore the damsel, but I want to check at the mill before cutting.
I had decided to make a damsel out three or four round bars forking out from a central rod, and converging back into one at the top again. I'm pleased to see, again from Walton, that the one at Kleine Zand Drift was indeed like that!
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