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Old 05-21-2020, 01:23 AM   #81 (permalink)
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Aerohead, thanks for all your feedback. I spent a bit of time crawling over the vehicle today with a tape measure. There is a bit more room than I had remembered at the start of the cargo area prior to the window to patch in some compound curve. Looks like at least 6 inches growing to 9. The cargo area is already tapered in with a minor amount of compound curve (.45 to .90 to 1.18 degrees) as you go back. I am contemplaing the angle to set the sides. Doing some overlays, i am considering aiming for 6 degrees right after the 6-9 inch transition. That results in the vechicle sloping from 76 inches down to approximately 60 inches over a lenght of 69 inches, pulled in 6.5 more inches per side from stock. This seems to reasonably align with a 4:1 streamline from a top view.

There really isnt a constraint on the angle i set provided it stays between 4.2 and 7.3 degrees, with rear widths between 64 and 57 inches for that range. Obviously this is a big project so I would like to squeeze out as much as possible.

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Old 05-22-2020, 01:27 PM   #82 (permalink)
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Aerohead, thanks for all your feedback. I spent a bit of time crawling over the vehicle today with a tape measure. There is a bit more room than I had remembered at the start of the cargo area prior to the window to patch in some compound curve. Looks like at least 6 inches growing to 9. The cargo area is already tapered in with a minor amount of compound curve (.45 to .90 to 1.18 degrees) as you go back. I am contemplaing the angle to set the sides. Doing some overlays, i am considering aiming for 6 degrees right after the 6-9 inch transition. That results in the vechicle sloping from 76 inches down to approximately 60 inches over a lenght of 69 inches, pulled in 6.5 more inches per side from stock. This seems to reasonably align with a 4:1 streamline from a top view.

There really isnt a constraint on the angle i set provided it stays between 4.2 and 7.3 degrees, with rear widths between 64 and 57 inches for that range. Obviously this is a big project so I would like to squeeze out as much as possible.
There's a plan-view image of Cybertruck online. Tesla gave it 6-different widths, kind of a planar approximation of body side camber. From the rear of the rear door cut line, Cybertruck is boat-tailed to the end of the vault. Very much like what you're going after on Deep Blue. A great mod!
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Old 07-19-2020, 03:09 PM   #83 (permalink)
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A minor update, after stripping the interior and removing the fuel tank the angle grinder came out and removed the rear doors. No turning back now.

Same basic plan, narrow the rear leave the height the same. I am considering converting the rear to a lift up hatch. (E.g 3rd gen 4runner) Pictures to follow later, work to do now.
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Old 07-20-2020, 09:20 AM   #84 (permalink)
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Here are some pictures of yesterday's "progress." I carefully removed the metal near the front of where the taper starts because that area needs compound curved. I also started to do a few cuts on the inside where I know things need removed. Spend most of the time looking/planning more so than cutting at this point.
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Old 07-20-2020, 11:35 AM   #85 (permalink)
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Here are some pictures of yesterday's "progress." I carefully removed the metal near the front of where the taper starts because that area needs compound curved. I also started to do a few cuts on the inside where I know things need removed. Spend most of the time looking/planning more so than cutting at this point.
Looking like commitment. I like it. How are you going to accomplish compound curves? Asking for a friend...

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A minor update, after stripping the interior and removing the fuel tank the angle grinder came out and removed the rear doors. ...
"Minor"!

Nice to see an ambitious mod make progress. I agree with aerohead in an earlier post: you can with these somewhat harder edges get some significantly lower drag.

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Old 07-20-2020, 12:19 PM   #86 (permalink)
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Compound curve will be accomplished via english wheel and planishing hammer. Note detailed sheet metal work is relatively new ground for me, I am not a bodywork expert, but with enough time and bondo anything is possible.
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Old 07-20-2020, 01:46 PM   #87 (permalink)
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Compound curve will be accomplished via english wheel and planishing hammer. Note detailed sheet metal work is relatively new ground for me, I am not a bodywork expert, but with enough time and bondo anything is possible.
Sounds great. Good clean compound curves, with smoothed welds and polished metal, are an amazing thing of beauty. I hope you'll share progress on that work. Will be fun to observe.
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Old 07-22-2020, 11:27 AM   #88 (permalink)
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Compound curve will be accomplished via english wheel and planishing hammer. Note detailed sheet metal work is relatively new ground for me, I am not a bodywork expert, but with enough time and bondo anything is possible.
A copy of 'The Key to Metal Bumping', would be an indispensable companion if you don't already have a copy. Eastwood is a great source.
There are old-world metal-crafters in Europe that can make anything with a hardwood tree stump, hammers, mallets, dollies, spoons, and a leather shot-bag.
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Old 07-22-2020, 03:58 PM   #89 (permalink)
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A copy of 'The Key to Metal Bumping', would be an indispensable companion if you don't already have a copy. Eastwood is a great source.
There are old-world metal-crafters in Europe that can make anything with a hardwood tree stump, hammers, mallets, dollies, spoons, and a leather shot-bag.
Edward De Vaucorbeil, a "French native metalshaper granted an extraordinary ability by the U.S. Gov.," is on Instagram with the handle extraordinary_metalshaping. Some examples of his most recent postings... pure beauty in craft...

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Old 07-22-2020, 04:30 PM   #90 (permalink)
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The final stages could borrow from paintless dent removal techniques — a glancing high-powered light and nylon pencil-pointed pecking hammers.

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