Hello together,
since I was still not satisfied with the last rounding step to the final gutter diameter of approx. 2.0 mm, I have tinkered at a better solution.
At first, I have made a few longer core wires for the longer half-pipes to get the curves evenly over the entire length.
With the last core wire of Ø 1,5 mm I get with the 0.1 mm aluminum sheet to approx. 1.7 mm, only I had to widen the gutter again and again, since the top edges are always rounding slightly again. With my previously used rectangular strip (1.5 mm x 5 mm), however, this did not achieve uniformly enough, especially with the longer gutters.
That is why I have sanded a 2 mm balsa board on one side down to a thickness of approx. 1.7 mm and rounded the edge in order to be able to widen the last rounding accordingly and to smooth it, which I have tested then at the end of the
Gutter 1.
This may work in principle for short gutters, but is not a good solution for the longer gutters, since the Balsa board is too little stable in shape over the length and can partly be pressed in.
That is why I have choosen another, somewhat more complex, but more stable solution with a plastic strip.
But since there is no commercially available wider strips with about 1.7 mm thickness, I have made it myself.
For this purpose, I have cut a handy strip of 15 mm x 150 mm from 1.5 mm styrene and glued on both sides 5 mm wide strips of 0.1 mm Styrene, for which I used MEK, wherewith the composite strip is then approx 1.75 mm thick.
The more difficult part was then the smooth rounding of the edge, which took some time.
But with this core strip, it can be handled very cleverly by clamping the gutter into a Balsa "vise" to smooth it, without slipping or tilting.
And with this more sturdy plastic core, the desired half-round shape of the longer gutter should be doable reproducibly, which is very important.
And if this method now works as well with the longer gutters, which I assume, this would be great.
