Sunday 16 March 2014

Back to the drawing board                                         

I have put my analytical hat on in order to methodically approach the Mystery of Non Fitting Triangles.
The first problem: due to its shape (tapering angles) I can't accurately measure the size of the triangle.
Solution: make slightly oversized model and see how my shapes fit on top.
 If I haven't totally blundered in making the shapes, the angles should match....
and they do.
So do the angles on the brackets.
in the moment of practical inspiration I drew the clay shape on the transparency and copied it 6 times. Position of the holes is important.
And there I found it!
The hole on the bracket needs to be 5 mm further from the center. Therefore the bracket needs to be 5 mm longer on each side, as you can see on the paper model (right).

So, back to the bracket making, measuring, connecting and testing the theory....
and this time it works:



Do you want to see it right way up?



It fits! It fits! It fits!
(Of course, that is only first 6 out of 180. And I made 12 brackets out of 540....)
But I will keep those thoughts at bay, and finish with a quote from the father of geodesic domes:

“When I am working on a problem, I never think about beauty........ but 
when I have finished, if the solution is not beautiful, I know it is wrong.” 
Richard Buckminster Fuller



Tuesday 11 March 2014

Sometimes it is good to be impatient                                                        


,,,,or would curious be a better word?

couldn't wait to connect first 6 triangles and see how they fit together,  so I "bravely" ventured into the unknown metal brackets territory. I soon discovered that steel is too hard for me to work with, but luckily, my husband Vlado spotted aluminium flats next to the steel ones in the hardware shop, so I bought a meter to try it out.
Working with a trial and error method, I (thanks for the patience Vlado) figured out how to cut, drill and bend aluminium flat into the bracket resembling the drawing ( see previous post).

I only had to make 12 brackets to connect a hexagon and here it is, first connections:



I can't tell you how exciting it is to put 2 clay shapes together with a metal bracket and it's not  falling apart.

Four of them together..still holding...but I feel the first seeds of doubt. The shape is not quite what I imagined.

And the 6th triangle just doesn't fit in. Not enough space.


Where did I go wrong? the hexagon shape I am getting is tighter and more pointy than expected, and no way to "flatten" it a bit.
I find it hard to resist the urge to flatten the angle on the brackets to see if that would help.
I need to properly diagnose the problem.....

Isn't it good I only made 12 brackets, rather than commissioned someone to make 540?

Saturday 1 March 2014

Are we there yet?                                    

There comes a point in the journey when the road seems to stretch forever, there is only a climb and no summit, only the ocean and no land, and it seems to take lots of motivation and energy to make another step.....or in this case; another triangle.

As the number of made triangles grows, and firings are happening without further problems, my mind turns to the next step in the process, the next unsolved bit: connecting them together.
The plan is to glue the bolts into the holes made for the purpose on the triangles, make metal brackets and screw them together.
I am really pleased with the way  bolts fit into the spaces for them:


If you don't work with clay, you are probably wandering why is this such a big deal. The thing is, the clay shrinks...and every clay shrinks differently so the exact size is difficult to predict if you have not tested the clay.

Here is the shrinkage example:

First triangle (top left) is freshly made, second is leather hard and third bone dry.
Bottom row: first is bone dry, second bisque fired and third glaze fired to 1210oC.
Lines are 3 cm apart.



There are several unknowns left to solve: I don’t know which adhesive will be strong enough for the purpose, so I will need to test a few.....starting with the one recommended by the professional shop, claiming to glue ceramics, glass, wood, marble, metal, etc.....which failed miserably.


Resin is showing promise. First test was holding the screw firmly in the hole, but in a few days it broke off like a rotten tooth.
 I realized I used 10 x the recommended amount of catalyst....so I mixed another batch and it is looking good:

This is the first prototype for the brackets:

it needs the hole for the bolt on the left side, but at the moment I'm using it to test the strength of the glue.
I will need to make 540 brackets, and I don't have a metal workshop, just few basic tools. This is one of the moments when I'm sorry I don't work at art school any more. Access to the metal workshop was a nice privilege.
This is the plan:


I am pretty sure it will work. I think. I hope. Wish me luck. Please.....