Prototyping and designing the rear battery boxes in 3D

It’s been an while since my latest blogpost. In that update I had just cut a spare wheel part from a donor vehicle. After that I went on holiday, was busy working and we organised a camp-week at our Mommenhoeve.

In between I have been able spending some time working on the car. I drilled the spot welds out to remove the spare wheel area from the rest of the donor vehicle.

losboren achterkant combi

It turned out it wasn’t good enough to be used as is.

donor achterkant te slecht

In the end I have decided not to repair and re-use this part. Instead I will build a battery box that goes up until the chassis beams. The disadvantage of that approach is that the spacing for easy mounting of the tow bar/bumper bolts will be removed.

Prototype battery box

So I continued with the battery box by adding the rear end.

batterijbak achterkant zelf maken

I want to keep the original long tow bar. Not to tow things around but as an additional protection of the batteries. This will however exactly fit with only millimeters of room left. Time to use and test fit my dummy modules again.

passen batterijenbak met isolatie

At the end the box hits the tow bar so I made another fold. Now it more or less is as it used to be with the original spare wheel area wall.

achterste rand omzetten

Now I have exactly enough room inside and spacing towards the tow bar.

speling tot trekhaak

The prototype is not fully symmetric and exact so I continued drawing again.

3D CAD drawing

My previous 3D drawing of the bumper mount holders were made in Onshape. Nowadays this is no longer supporting ‘private’ drawings in their free version. Therefore I had purchased ViaCad. I could not get used to this software and create the designs that I wanted to. Therefore I asked Bas to help me out again. Together we found out that the capabilities of Viacad were not matching our expectations.

Therefore I decided to continue using Onshape again, even with my designs in the public domain. Thanks to the help of Bas, the first bit of the car was quite easily created. I start to get used to it again already.

achterkant auto tekenen

Of course it needs to be detailed much more, but the basis is there. Furthermore we started drawing the tow bar. We used a photo as a starting point.

trekhaak tekenen

Next steps will be drawing more components of the car and completing the tow bar after which the two can be combined in an assembly.

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OldVolvo is a classic Volvo hobby blog by Lars Rengersen.

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