Boat tail easy

[Phase]

Originally Posted by freebeard

I support the decision. Each case is individual. My Metro barely fits it's parking place as it is. Mair, et al, supported truncations.



When you move on, consider getting a 2+ foot strip of heavy-gauge sheet aluminum and find someone to Engish wheel it into a contour that you can hold up to the car and crimp edges to finalize the fit. Then hammer and dolly the crimps flat again and trim it all down.

Else get a 1948 Buick hood and cut the contour you're looking for out of it. Remember Jimmy Jones?

kustomrama.com/wiki/Jimmy_Jones_Bubble_Skirts



edit:

I’ll probably use dibond again and luckily with heavy strength and pressure you can bend and shape it. I’ll have it attached to a harbor freight trailer that’s like 60 dollars that I can take on and off

To help with the boat tail I still need to smooth my underbody and get that rear diffuser too

[Phase]

Playing with angles of left over cardboard. Obviously not cut to fit. Will use stiffer material and a better attachment later

[Phase]

I’m seeing a lot of newer cars having this “ jagged” rear where the sides of the car don’t fully extend as much as the roofline or even diffuser area. Is there a reason for having this shape versus it being straight and blunt and the same length in the back? Or is it just styling? I’ve also noticed the back of my Ioniq has a similar shape, versus just being straight vertical on the sides

[Piwoslaw]

Originally Posted by Phase

I’m seeing a lot of newer cars having this “ jagged” rear where the sides of the car don’t fully extend as much as the roofline or even diffuser area. Is there a reason for having this shape versus it being straight and blunt and the same length in the back? Or is it just styling? I’ve also noticed the back of my Ioniq has a similar shape, versus just being straight vertical on the sides

The top and sides have an "edge" so that airflow detaches at exactly that point.

The top can be extended a bit, to better guide that air, and slightly reduce the rear wake. The only side effect is possibly shading the top of the rearwindow a bit. The protrusion ends before the rear bumper, so no risk of it catching on anything.

The sides, on the other hand, cannot have this extra protrusion, as it may catch on something while turning and/or backing up.

[aerohead]

Originally Posted by Phase

I’m seeing a lot of newer cars having this “ jagged” rear where the sides of the car don’t fully extend as much as the roofline or even diffuser area. Is there a reason for having this shape versus it being straight and blunt and the same length in the back? Or is it just styling? I’ve also noticed the back of my Ioniq has a similar shape, versus just being straight vertical on the sides

I'll guess that the Elantra is pushing the fascia out to extend the 5-MPH bumper where it will take the initial hit in a collision.
Mercedes is doing their upper overhang to recover as much pressure from the roofline as possible.
Any reason for not making the sides a clean 'chop' may date to 1927, when the Paris Dressmakers instituted the annual styling change, and design obsolescence. They can't stand for cars to 'look alike.'
Designers have told journalists that some of what they do is to create 'directionality' in a shape, like adding speed lines to a cartoon.
Aerodynamics demands that cars look identical, and fascias, front and rear are one of the few places where they can imbue corporate marque identity, to set their product apart from the competition.

[freebeard]

Serrated trailing edge.

[Cd]

My guess would be style.
If you notice, the Mercedes and Hyudai have their angles completely opposite.

Freebeard - I don't see the serrated edges - at least not small ones.

My understanding of these serrated edges, was that they cause the air to go slightly turbulent as it exits, acting like a vortex generator.
In the engine shroud application they are for, as you know, a reduction in noise.
BTW, I added serrated edges to my boattail at the edge of each segment for a clean attacment at each transition.
A solar race car used this feature for a clean airflow break just behind the driver canopy.

With the designs we see in the images, there aren't any "teeth" and I'm wondering if it would have the same effect that you get with several serrations.
BTW, my neighbor has that Hyundai.
It has vortex generators molded into the body just above the tail lights.

[freebeard]

Freebeard - I don't see the serrated edges - at least not small ones.

I see one big serration, or maybe it's a vortex generator.

[Phase]

I think the “ fish tail” angle at the edges looks better than a straight vertical line. I may incorporate it into my boat tail. Again, my boat tail won’t be the most optimized boat tail possible, I’m still going for some sporty style points like Mercedes and other makers

[COcyclist]

Originally Posted by Phase

I’ll have it attached to a harbor freight trailer that’s like 60 dollars that I can take on and off

Trailer hitch?