sepp's second aerocap

[PaleMelanesian]

Basjoos used lexan at a similar angle on his Aerocivic.

[MazdaMatt]

I think that's crazy talk, not being able tos ee through plexy or lexan at an angle, but if you're right, then just close it up and put a camera on it. $100 fix.

[sepp]

i already tried plexi before constructing the flaps, i just slammed an old leftover sheet of plexi on it (was really thick though 5mm, and wasn't as shiny as a new one) and tried to see how much i could see through. and the best i saw was a distorted and foggy image, add to that dust or water and you won't see anything.
even though i suppose a brandnew thinner sheet would give a clearer image, and a glass window would be way to heavy for this thin wooden structure to support.

let me have my beautifull james bond-like flaps!!

[winkosmosis]

I don't understand all this flap business.

Just make a window out of thin Lexan. You'll be able to see out of it, and it will never break. You could even use the clear plastic used on sails, as long as you keep it taut. Check your local fabric store. The stuff is cheap.


Or use a wide angle camera mounted on the roof in an aerodynamic pod.

[Thalass]

This is great. I want to do something similar with my brumby EV, though I'm going to go with a camera and video screen replacing the centre mirror. Not sure of the legalities, but I'm sure it's better than not being able to see at all!

I like the flaps you have there. As far as control goes. I think you should go with either a windscreen wiper or power window motor, with a linkage between the two flaps. It should be fairly easy to wire up a circuit with two limit switches, incorporate the reverse and/or brake switches and a manual override switch too. Might even be able to do it without semiconductors, too! heh.

[elhigh]

Here's my last input on this:
I would go with the Lexan. I have a window I made from Lexan here at work, and I often approach it from far down the hall - I can see very clearly through the window even as far as 75deg from perpendicular, BUT that window is cleaned every day. So your mileage may definitely vary.

THAT SAID, go your own way. It's your ride; if you want flaps, then by all means go for the flaps. Lord knows, if you can make it so you can reach in through them to fetch something out of the bed, without having to completely open the cap, then that's not a complication, that's a convenience feature. I can't tell you how many times I've wanted something out of my truck's bed, but it's more than arm's reach from the pass-thru, and more than arm's reach from the tailgate. And if the flaps are body color, then out of sight is out of mind, right? Less temptation for some mouthbreather to try to make an unauthorized withdrawal from your tool collection.

Vaya con Dios!

[FastPlastic]

I say keep the flaps. They may be more work, but they will be a hell of an attention getter (Kind of Batmobile like). It's just another way to show people getting good gas mileage can be cool too. Besides if you set them up with enough power to pop up at high speeds when you brake, it should increase your braking power.

[sepp]

ahh finally some that agree! an attention getter it will be alright, i just have to make sure its reliable and solid. otherwise ill get the wrong kind of attention.

little update:
frame view from the rear:

i like the shape it has, this time i kept the sideways shape of the car and continued it to the rear. only the top bends down gradually.
with my first cap i made the sides gradually bend inwards also, but it sort of looked weird from perspective. may have been better for aero though, but techically too complex with the aluminium i use now.



it's probably the most beautifull wooden construction i ever made, it's almost a shame to cover it. don't get scared by the complex looks of it, im the first to be impressed that i can actually make such a thing. and its not as hard as it looks.


started cutting out and adding the side plates and 1 flap, im pleased by the looks so far. it looks warped on the pic, but in reality the deformation caused by the bolts is verry minimal. the bolts are the best i could come up with, these are self tapping bolts we used for bolting sheet metal straight through steel frames. they may not be verry "aero", but they give it a "military" look i guess.

[Thalass]

That really does look awesome. With the screws holding the skin in, could you drill countersink holes in the wood and use countersunk screws? The alloy should pull into the hole and you'd end up with a flush(ish) surface. Especially now that you have holes in both metal and wood that match up, so you shouldn't have to worry about missing and screwing up! :P

[aerohead]

Originally Posted by sepp

thank you all, i was especially hoping for tips from aerohead. i think i will go for the polyester edges.

i thought long about giving it an airbrake, and maybe i will but not with these flaps. as i believe that if these are used to brake a 2 ton vehicle, that it will make the whole thing disintegrate.
i searched a bit but i could only find some actuators on some auction sites wich go from 26 to 160 €. i will leave that for the last and keep searching for a good find.

also does anyone know if some sort of spoiler would help? i was thinking of some kind of horizontal wing above the rear end. or is it better to let the cap end with a horizontal part that is in the shape of the cap like most car truncs or roofs end with.

sepp,I tried a spoiler at Bonneville and removed it after only one pass do to the drag it created.That was with the CRX,but the T-100 is also a fastback with the aero shell and I suspect that it would behave likewise.Allowing the air to follow the teardrop path appears to be the best for fuel economy.If you drive into Germany and get the Nissan onto the Autobahn,you might want some downforce a wing or spoiler could provide,otherwise,at "normal" speeds you should be alright.