Aero Crosstour- Squeezing blood from a stone

[Chonk_Master]

Ah. Too bad I don't have access to the car scales on base anymore.

[Ecky]

What I'm using instead of smaller mirrors:

[freebeard]

Ah. Too bad I don't have access to the car scales on base anymore.

Send it to me, I have one like this:

http://www.canfortlab.com/pic/big/453_0.jpg

[Chonk_Master]

Those side cameras are super cool, Ecky! Are those DIY?

So, prototype side mirror plate came out great. It's pretty insubstantial, so it only took a couple of hours to print.


Enjoy looking at my finger toes.

I went out and test fit this guy...

I'm about as happy as can be with that EXCEPT for something I forgot from the first mock up.

That little ridge along the top of the factory plate's recess. Yep, there's no allowance for that in my design. If I'm not holding the plate up (or it's not wedge in there) it'll fall out.

This is why we build prototypes.

I also looked to see that all the mounting holes had plenty of material underneath them so that I could securely heat set those threaded inserts when the time came. The rearmost hole was barely covered by PLA, so I went ahead and added a little cylinder of PLA underneath it. I also cut the subtractive out of the top of the panel for the ridge.

And viola:

This one I'm expecting to fit just fine. The factory weatherstripping actually looks pretty good against the prototype but I'll probably add some rubber underneath, juuuuuust in case.

Tomorrow, I'll look under the driver's side to make sure it's the same and figure out how I want to set the mirror against this plate. I had considered routing the hole out after printing but I think just doing it in CAD will be loads easier and prettier. Based on this photo, the base of the low-pro mirror will need to fit along the bottom edge of the mounting plate:


I should be printing the final product tomorrow night, painting and mounting on Sunday (knock on wood). I was going to use some filler to make everything perfectly smooth but this filament is printing fine enough that I'm pretty sure I can just sand it, paint it black, and poly it.

I'll have a bunch of errands Saturday morning but I'm pretty sure I can get a photo of the Crosstour in front of a big white wall behind the nearby Target for cross section analysis. That way I can proceed with install, even if I don't quite have the data on the area yet.

[Ecky]

Looking really good! I'm impressed. I have zero skill in the way of digital design. I asked forum member Daox to whip me something up and he obliged. They were printed in 4 pieces.

You can see some installed pics in my build thread in Ecomodding Central.

[Chonk_Master]

Aw, sweet. Yeah, this project also serves to teach me some CAD, even if it's just rudimentary. It'll probably take me a couple of hours to get the cutouts right. I've made probably every mistake you can so far and I'm far from efficient but it's something.

[Chonk_Master]

Welp, did a lot of running around town today and didn't get much done. I did manage to rig up this super sophisticated speedometer recording device.:

How much science did 3M enable with the advent of two sided tape? We may never know.

I tried to find a spot in town while I was out and about that would be good for doing coast down runs but the Chonk has momentum on its side and I need quite a bit of space to get down to ~10 mph. I work on the outskirts and there's a long, empty, flat road leading to the building. I can leave an hour early or so and bust it out Monday.

Also got the photo I'll use for measuring front cross-sectional surface area. The scale is 46" long. It's not a yard or a meter stick, it's a 46"-stick.

I'll cut it out in Gimp, make a cutout and copy of the driver's side mirror and paste it on the passenger side, and then let MIPAR do its thing.

Tomorrow, I'll drill holes in my spare lugs to see if I want to use them to mount the pizza trays and to keep some forward movement going.

[Chonk_Master]

So, made a rough outline of the front of the vehicle in Gimp. I did this by hand but it looks like ImageJ and MIPAR can make this a lot easier.

By the way, I switched to ImageJ for analyzing the image. MIPAR was a level of complexity and capability above the scope of this project (let's say).

Anyways, here's a screenshot of the image before it was analyzed:

As you can see, the 48" level (it's 48', not 46") was left in to act as a scale. It was sitting level with the front of the Crosstour when the photo was taken.
You can also probably see how I cut out, mirrored, and pasted the driver's side mirror over to the pass. side. Impressive, I know.

Long story short, ImageJ has a tool that let's you draw a line across some feature in the image and say "this is 48 inches long". It then applies a pixel/inch scale to the entire image. You can use a few different, more sophisticated tools to outline what you want to take the area of, but I just used their magic wand tool, since my image was a pretty rough outline anyways.

Here's the analyzed image in ImageJ,with the Crosstour magic wanded in yellow:

Because of the earlier scaling, I think the units for that area are in square inches.

So, 2647.045 square inches becomes 18.382 square feet or 1.71 m^2.

For reference, just going by height and width, the Crosstour is 34.375 square feet or 3.19 m^2. That's, like, 53% so I'm guessing ImageJ didn't do a good job of measuring OR it used different units than square inches.

OR it could be everything that's missing underneath the car in the image. Not sure.

At any rate, I took measurements for distance from the car and camera height, so I can recreate this experiment relatively easy. If I can't figure out the exact area, I can at least get a good idea of how much area was decreased.

[freebeard]

Good effort.

OR it could be everything that's missing underneath the car in the image. Not sure.
....
That's, like, 53% so I'm guessing...

Delete the wheels and tires and compare the result?

[Chonk_Master]

Right? Something like that. I may also add everything that's under the car back and try that. I'm also wondering about the angle of the photo.

I checked the 48"-stick again, it's definitely in inches. The graduations are labeled "8ths" and "16ths", so I don't think it's that. I may have fudge the scale but not enough to give up ~20%.

I need to get a hold of a Honda engineer.