zaterdag 2 maart 2013

First building week

First week of actual building, first week of finding many challenges... The first day I started cutting, sawing and filing down plates for the hinge joints for the elbow of the wing. Just getting things straight and neat and lining up nicely is already a challenge.


Most of the week I spent finding a solution to drill the ball bearings, and that was the start of weeks full of problem solving... From my research I had read about simple methods using plates with holes to clamp the ball bearings. I could not get that working. I talked with Ryan from fabrication about possible solutions and we came to making something similar to the tool in the existing 'kit', but a bit more simplified: two thick metal plates which have a sockets where the ball sits in and is clamped in between, with a through-going hole the size of the rod that should fit in later in the middle to place the drill bit at the right place when drilling. The two plates should be clamped together and then clamped in a vice.

First thing to be done was learning to use the plasma cutter. I would use this to cut squares from the thick steel plates. It took some practice to get used to the round flying sparks and limited sight (from wearing the mask) but in the end I had two squares cut off. I could still makes the edges straighter and smoother using the belt sander. After finishing the first version of this tool I found out I had made many mistakes...  First of all it wasn't a good idea trying to make the clamping plates suitable for both sizes steel balls. No way I would get both clamped with equal force... Second, I found out after drilling the first ball that I had not been able to get the hole for the drill bit in the centre. Third, after drilling the second ball, I found that the ball had moved while drilling and so the hole was messed up. Now I realized that I had made a crucial mistake here: I had actually created a little box for my steel balls instead of a clamp, as they were fitting in perfectly, and therefore were not being clamped... Ok, next try.

After talking with Paul (staff in fabrication centre) we came to a solution of using a series of drills for the centering problem. In this way I could drill the small hole for the drill bit first, then fit a slightly bigger drill on there to drill only slightly. Then one size bigger, another size bigger, etc. Until ending with the size needed for the ball bearing to fit, but only drilling the hole slightly, checking all the time if the ball would fit but still be clamped between the two plates. 



This time my confidence using the plasma cutter had improved and this time I cut four plates to be making two seperate clamps for the different sized balls. This time the clamp was a success and thursday afternoon I got 17 balls drilled. These were the bigger, already annealed ball bearings. On friday I tried if I could anneal the smaller steel balls I had with a brazing torch but that was no success. Another thing to research more about.



Finally on friday I had a signup session with Mary and got some good feedback and advice on methods for soldering ball bearings onto rods, and about how a heavy armature will affect the ease of animating it. The heavier the armature, the tighter the joints have to be in order to stay in position, which means fighting the armature more while animating it. Something to consider especially for my wing design, which could work out to be quite heavy...



Geen opmerkingen:

Een reactie posten