As you will know I have been striving to finish my Bessler’s wheel. Given several requests to finish the wheel or shut up, I thought I’d try to give some idea of why it is taking so long and the difficulties to overcome. If I give away some small clues along the way, I don’t have a problem with that. You may well find that what follows is utterly confusing as I try to describe some problems I encountered, without illustrations, but perhaps you’ll get some idea of the difficulties I’m trying to resolve and recognise them from your own builds. These same problems are typical in this kind of research if you actually do hands-on builds.
The concept I’m working with is very simple and I can understand why Bessler feared that once people knew how it worked they might think the price he was asking was too high. In addition there is Karl’s comment about it being so simple a carpenter’s boy could make one if he was allowed to study it first. However I think his comment is misleading; even though it may be easy to understand, designing the mechanisms so that they operate correctly is another matter altogether. You might look at the workings of a clock and understand how it works, but making a copy would be difficult and you might not understand how different parts interact and their purposes could easily be misunderstood. Imagine trying to do that without the device available to you, just some brief descriptions explaining how it worked. That is what we are trying to do.
A carpenter’s boy, meant apprentice, and in those days it was a way for young men to acquire skills in various trades. Apprentices were formally bound to Master craftsmen for several years, without pay but provided with board and lodging. Upon release from his service to his master, an apprentice would have become a highly skilled craftsman so we shouldn’t dismiss Karl’s comment as implying the wheel was easy to make, I think he was suggesting that the concept was easy to understand.
In my version there are five mechanisms, which I know goes against current opinion. The mechanical action is quite complex, but nothing as complicated as a watch for instance, but seeing a working version where all the parts have been perfected to work together, would make it easy to copy, whereas only knowing the concept and designing it to work is not as easy. I found that the mechanical arrangement leads to some parts interfering with the each other, so I needed to provide more room for each part to operate. The extra room has to be found within the thickness of the wheel rather than its diameter. This requires longer or taller pivot points than one might at first assume, because one part of the mechanism needs to be separated and held apart the other part of the mechanism. If viewed upright on its axle, then there needs to be enough room within the thickness of the interior to allow all parts to operate without touching each other. But to do this one has to get the moving parts in the right order through the thickness of the wheel so that each piece can operate smoothly without interfering with the other parts. I know, this is hard to understand without seeing a drawing.
I believe I’m in between the point at which Bessler said he had found an action but it still took him time to design the whole working arrangement and the finished wheel He made a similar point in his message on the front of his Maschinen Tractate (MT)
There are a number of nuts and bolts, some of which have to hold two or three pieces together without allowing them to rotate against each other, whereas other nuts and bolts have to allow the pieces they are holding together to rotate against each other. This is easy enough to arrange, but in some cases two of the pieces being allowed to rotate against each other cannot be allowed to rotate in such a way that the bottom of the nearest bolt is not clear of the moving part during the path of its rotation. So even these have to be separated a little.
His first wheel at Gera, was only four inches thick which leaves little room for the mechanisms to operate. But although I did not concern myself with trying to fit everything within the limited space of four inches, in the process of avoiding mechanical interference I found a solution, which was to apply a slight double bend in the levers which altered their path at a particular point along their length thus avoiding the collision.
In addition to these factors some mechanical actions have to be designed to work in one direction only, so that they thrust in one direction but then return as a consequence of the wheel’s rotation.
Dealing with cords, ropes, string, cables, chains or belts - what ever you wish to call them - requires more ingenuity because there are points during rotation where the connecting material is taut and others where it is loose and in danger of fouling other mechanisms, or parts of them. So keeping the cords out of the way means they need to always have a small amount of tension in order to keep them clear of all other pieces.
We know that Bessler was familiar with the workings of the church organ, so such concerns as outlined above, might well have been customarily encountered and for which there were remedies. In my opinion, Bessler’s response to the question of springs indicated that springs were used to maintain tension in the cords, but had no part in helping the mechanisms.
Fitting the mechanisms on to the backplate or wood disc which I use, is simple but I found that the wood disc was never big enough. The path of the mechanical actions can be estimated but for some reason although I always tried to place the mechanisms where I had worked out that they needed to go, I would then discover that the mechanisms were shooting over the edge of the disc and either catching onto the side edge of the disc or striking the floor when it was attached to the axle and it’s stand.
These are routine problems I have encountered from time to time over many years, but I am getting there. Soon I hope to finish, but my fear is that my wheel won’t work properly without my having to unstick a mechanism or help a rope to move or some other snag which may cause problems because I lack the necessary skill and equipment. If that happens I’ll just have to publish everything, but I was hoping to avoid the problem Ken had in publishing the design of an unproven device. But I will of course publish my design freely and without charge.
One more thing, as a consequence of comments in the preceding blog, I would just point out the difficulties described above would not show up in a sim, so although it might show a successful build, the detail for the build would still require considerable experimentation, trial and error.
JC