After hunting around for a while and trying a couple of different metal box configurations, I decided to make my own out of Bondo fiberglass. I’m going to post that whole experience here soon, but here’s how it turned out:
Not terrible, but a little on the wavey/lumpy side. Also i totally wouldn’t blame you if you were like “uh, no.” because Bondo fiberglassing resin is horrible to work with. It just happens to be readily available at Lowes and its a third of the price of something real, like West System 105. I’m not going to waste words lamenting its horrors here, as I have a build thread planned out in which the true terror of Bondo will be revealed. I will post it as soon as my rig is reassembled and ready for pics.
Also, Vacuum molding of ABS plastic sheets is a very good option for the DIYer. I’m going to try that next. ABS sheets can be had cut to measurements from TAP plastics for about $10 per sheet. A vacuum table can be built from leftover 2x4s and some pegboard, then plug your shop vac into a hole in the side. Use an old metal screen to make a metal frame for your ABS sheet then heat in the oven till it starts to droop, pop it on the form, flip on the vacuum and “flump” you have a box.
All that aside, I just did a precursory search and found that Alien is completely out of their carbon fiber boxes, in fact they seem to be out of all of their boxes. They used to have a pretty wide selection. I just can’t recommend metal boxes after the experiences I’ve had with them, but i believe @torqueboards is designing a plastic box that should hold what you’re talking about. I’m not sure when that’s going to be out though.
I’ve seen a number of plastic “project boxes” online though and if you google those you may come up with something close enough.
But what really got me interested in making my own using the method i used was the fact that its basically the only way to have one that follows the curve of your concave. Even Alien’s were flat on the bottom and unless you use an identical deck to make your vacuum mold, even the ABS option won’t match up with your curve.
Hope this helps.