If you hold loosely two tips of any rope, especially a chain (because it is heavier than a rope), it gives a parabolic shape. So you don't have to calculate for drawing.
I just googled it and the curve is not parabola, but actually catenary curve, which appears to have wider angle of curve the further to the ends. The wider areas would not be contributing to the focal point of the rest of the mirror. Perhaps you could sketch out the real parabola shape by eyeball after tracing the rope.
I chose cement because it remains a long time, even in rainy weather. So you can make several reflectors one after the other. But I actually also used gypsum (see 8:00 - 9:40) because it can be sanded finer than cement. Perhaps I should have used the term "plaster" instead of "gypsum"; it's probably just a translation error, sorry.
Danke für die Idee vom Chrom-Spray! Ich habe kürzlich einen solchen Spray gekauft und Tests gemacht. Gemäss Internet-Recherche gibt es sehr unterschiedliche Qualitäten, was den Glanz und die Wasserfestigkeit anbetrifft. Der von mir gekaufte Spray hat die Unebenheiten des Untergrunds in keiner Weise ausgeglichen, es ist also noch mehr als beim Aufkleben von Alufolie wichtig, dass der Untergrund möglichst schon spiegelglatt ist. Auch von Vorteil ist es, wenn der Untergrund nicht saugfähig ist. Schliesslich war mein Spray auch bei perfekt spiegelglattem Untergrund etwas gräulich und daher weniger reflektierend als Alufolie. Ich werde aber noch weitertesten, und wenn ich das „Ei des Kolumbus“ finde, so werde ich es auf meinem UA-cam-Kanal oder meiner Webseite (www.cumaru-pe.com.br) kommunizieren.
How did you calculate the parabola? What was the formula? It doesn't look right, does it have a tight focus. I looked at your pdf, but a formula didn't jump out at me.
The formula is y=0.5.x.x/f, but I see that I made an error in the pdf-Document. I take all the contents about the solar cooker from the Internet until everything is fixed. Sorry and thanks for advising!
أشكركم على مديحك! إذا كنت تصنع طباخًا شمسيًا ، فسأطلب منك مشاركة تجاربك معي. قريباً سيكون هناك وصف لطباخ ورقي يعمل بالطاقة الشمسية على هذه القناة. مع أطيب التحيات!
What the actual hell did I just watch? I want the 5 minutes I wasted of my life back! There is a reason that not every man should try building things. You wasted materials and time on a project that can be easily done in a fraction of the time with far less effort.
I'm sorry you wasted 5 minutes of your life, but it's not my fault because I didn't ask you to watch the movie. By the way, I am very curious about your suggestions for improvement! Greetings!
Thank you again for the punctual reply. I will be using plaster of paris, it will be 91 cm in diameter.
I wish the link to the next part was in the video description. Going looking for it now.
Part 2: ua-cam.com/video/s34NRYzmL6c/v-deo.html
Part 3: ua-cam.com/video/cSrxndJZOjE/v-deo.html
Definitely the most epic parabola-making music I've come across!
Nice work!
I love the music, thank you! :)
amazing job. you're liked
Fantastico We need it there in India Maybe one day you can visit us and do there in land of my friend
If you hold loosely two tips of any rope, especially a chain (because it is heavier than a rope), it gives a parabolic shape. So you don't have to calculate for drawing.
I just googled it and the curve is not parabola, but actually catenary curve, which appears to have wider angle of curve the further to the ends. The wider areas would not be contributing to the focal point of the rest of the mirror. Perhaps you could sketch out the real parabola shape by eyeball after tracing the rope.
Thank you
WONDERFUL. Thank you so much for sharing it. Where are you from?
I am Swiss and live in Switzerland, but I spent a lot of years in Brazil.
Why did you select to use concrete to make the form? Did you consider plaster?
I chose cement because it remains a long time, even in rainy weather. So you can make several reflectors one after the other. But I actually also used gypsum (see 8:00 - 9:40) because it can be sanded finer than cement. Perhaps I should have used the term "plaster" instead of "gypsum"; it's probably just a translation error, sorry.
Very nice
A grande modrlo em escala da Enterprise do antigo seriado Star Trek, dos anos 60, foi construida assim, no refetente a área circular, soucer section.
Focal point should be within the dish to avoid any accident. It should be a short focus deep parabola.
hey Bruno, danke für die tolle anleitung!
hast du schon mal chromspray benutzt statt der folie? denkst du das geht?
Danke für die Idee vom Chrom-Spray! Ich habe kürzlich einen solchen Spray gekauft und Tests gemacht. Gemäss Internet-Recherche gibt es sehr unterschiedliche Qualitäten, was den Glanz und die Wasserfestigkeit anbetrifft. Der von mir gekaufte Spray hat die Unebenheiten des Untergrunds in keiner Weise ausgeglichen, es ist also noch mehr als beim Aufkleben von Alufolie wichtig, dass der Untergrund möglichst schon spiegelglatt ist. Auch von Vorteil ist es, wenn der Untergrund nicht saugfähig ist. Schliesslich war mein Spray auch bei perfekt spiegelglattem Untergrund etwas gräulich und daher weniger reflektierend als Alufolie. Ich werde aber noch weitertesten, und wenn ich das „Ei des Kolumbus“ finde, so werde ich es auf meinem UA-cam-Kanal oder meiner Webseite (www.cumaru-pe.com.br) kommunizieren.
@@brunokagi1090 haha danke! ;)
How did you calculate the parabola? What was the formula? It doesn't look right, does it have a tight focus.
I looked at your pdf, but a formula didn't jump out at me.
The formula is y=0.5.x.x/f, but I see that I made an error in the pdf-Document. I take all the contents about the solar cooker from the Internet until everything is fixed. Sorry and thanks for advising!
Die Anleitung ( PDF und Videos ) werden jetzt in Kuba zum Bau von zunächst EINEM Solarofen verwendet
ممتاز
اتقان
عمل ممتاز جدا وشرح ممتاز
أشكركم على مديحك! إذا كنت تصنع طباخًا شمسيًا ، فسأطلب منك مشاركة تجاربك معي. قريباً سيكون هناك وصف لطباخ ورقي يعمل بالطاقة الشمسية على هذه القناة. مع أطيب التحيات!
@@brunokagi1090 سعيد بتواصلك
فهمت الفكره وهنفذها بمصر Egypt
اريد التواصل معاك
How much resin did you use to make the reflector? I'm interested in making one also.
Hello Andy! I used 3.5 liters of resin. In the film description you will find a link to a pdf document. It describes all the details. Greetings Bruno
Thank You
What are the materials use to mold the fibre dish?
In the description of the film you find the link to a pdf-document with all necessary informations.
How you calcolate the parabola?
Please see cumaru-pe.com.br/English/renewable-energy/. Good luck!
Or;just get an old satellite TV dish and coat with Mylar.
First!!!!??!!?!??!?
spin-cure epoxy
coat the epoxy parabolic surface
Beethoven.
Are we at a concert! Cut that music
Hit the "mute" button, cry baby. Or upload your own video.
What the actual hell did I just watch?
I want the 5 minutes I wasted of my life back!
There is a reason that not every man should try building things.
You wasted materials and time on a project that can be easily done in a fraction of the time with far less effort.
I'm sorry you wasted 5 minutes of your life, but it's not my fault because I didn't ask you to watch the movie. By the way, I am very curious about your suggestions for improvement! Greetings!