Actually used trig...

nakman

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Not sure if anyone else has the "when am I ever going to use this" discussion with their kids. Seems to be a somewhat recurring theme at my house, particularly as math gets harder in high school. If that's you also, well maybe this story will help next time it comes up.

So here's the story: I sell cross bars as a solution for OEM racks. Today a customer wants reduce wind noise and put a fairing on their extrusion cross bar setup. Ok easy enough, here's a pic that they sent...

IMG_3336.jpeg



I make a bracket that runs over the top of that 1x2 extrusion, then bends down at a 50° angle. Here's what that looks like in magical CAD space...

1748543900533.png


And as I'm literally typing the words "measure to make sure a 4" tall fairing at a 50° angle doesn't touch the roof" I realize that I posses the power to figure out what that number is vertically. So I then create this picture, then run upstairs and plop down on my daughter's bed to make her help me figure it out...
1748544183227.png


So we first agree that the missing angle must be 40°, as the sum of the angles of a triangle has to be 180. It's refreshing to know they still teach SOH CAH TOA in school, albeit with fewer Native American references than when I went through it, probably for the better. So after a little more deliberation we figure the SIN of the 40 degree angle is probably the easiest way to find X... given that S=O/H, and we are trying to find O and already know H. So SIN40=X/4. Sin of 40= .745, then times 4 to get rid of the fraction = 2.98. So I then write my customer back and say measure down from the top of your cross bar and make sure you have at least 3".

ha! today is when you'll actually use this stuff. :)
 

Notyourmomslx450

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I had no clue you sold cross bars for OEM racks.... I was looking at your site and found the listing with the vehicles that they would work on.
Think you have something that would work on or Lexus RX400? The stock bars don't move as some parts have broke making our Thule roof box useless for that car. It's our primary road tripper and need something....
I'd much rather use a friends company, rather than rack attack or someone else..

Thanks Tim
 

nakman

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I just use SolidWorks!:cool:
nerd.


Andy, I don't think so, at least not a straight bolt-up. All my current OEM rail products rely on the inside channel, where I'm using some channel nuts. And I think your RX rails are smooth on the inside, correct? So to make them work you'd have to add some holes, and in that case just tap threads... and ooo you could use one of those cool drill/taps I just posted a video about. So actually yeah, this could totally work, let me know if you want to check it out sometime.
 

timmbuck2

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nerrrrrrrrrrd

:hill:
 
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