Rear battery frame prototype and further designing

I’ve been working on designing the rear battery box. In the end the box needs to be completely (air) tight so just using the current spare wheel lid is not an option. To design a additional custom cover I took the curves.

overnemen contour

And sketched them in Onshape.

curve overnemen

Building on this and the size of the spare wheel opening I designed a rim that I can weld in to support the new lid plus a stainless cover.

deksel met lasrand

The weld rim will be positioned onto the bottom edge of the opening.

lasrand in auto

I printed the drawing to scale and checked the roundings. In the weld rim I will used rivet nuts.

controle print contour op schaal

Fits like a glove.

contour past in auto

Building the battery frame

I ordered some more steel tubes and the aluminum ones.

staal ijzershop

aluminium op maat

Using drawings that I generated from my designs I could start building the frame.

frame lassen met tekening

And test fit a battery module.

module proefpassen frame

My idea of the milled slot does not work. I can’t tilt it in and have it tight enough between the frames at the same time. Alternatively I will just bolt all three sides down onto a support.

Nevertheless I also made the second part of the frame and installed it in the car for a test fit.

module proefpassen achterste frame

Works out very well as planned, including the height of the front stack.

module in auto

And the good news: the original tow bar does indeed fit!

trekhaak past

The frame itself is quite heavy and feels a little oversized. Perhaps I can explore using 15x15x1,5 instead of the current 15x15x2 mm tube.

Furthermore I’m going to change the way I construct the middle frame. Installing the modules is quite a hassle. I’m going to try and see whether I can stack the whole middle frame using aluminium tube and then bolt the whole thing down at once with some long threaded ends.

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OldVolvo is a classic Volvo hobby blog by Lars Rengersen.

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