Can't triangulate next to the transmission

[tibimakai]

I have build my chassis pretty close to the transmission, and I don't have room to add triangulation tubes.
Transmission has some bulges that would interfere with those tubes.
My question is, it would be OK, to cover that space with a piece of sheet metal instead? It would add similar strength to the chassis?
16 gauge sheet would be enough for this purpose?
Since I'm talking about steel sheet metal, I would like to find out, where else do I need to add steel sheet metal, footwell as I see everybody covers that are and makes sense for safety.
I also see that some add next to transmission tunnel between seats. What purpose serves that, against the driveshaft?
Also, I see some add sheet metal to the outside next to the seats, but that is understandably for live axels mount strength. Since I will have IRS, do I really need that area covered?
For street use, do I need a driveshaft hoop?

Thank you,

Tibor

[Lonnie-S]

Yes, you can weld in sheet metal on the outside to give stiffness & triangulate. You could rivet them on too, but stitch welding as shown in the following photos works well and takes much less time.

Cheers,

DSC04371.JPG

[tibimakai]

Thanks Lonnie, but the issue I have, is exactly next to the trans, in the V shape.
Right there, where you show in the picture, I have placed some 3/4" tubes.

[tibimakai]

Here are some older pictures:
The arrows show the bulges.

[rx7locost]

Why not triangulate like this?

[tibimakai]

That longest one, most likely would be in the way, when I want to remove the transmisssion, by pulling it forward.

[rx7locost]

You could make that piece removable.

[tibimakai]

That is not a bad idea. You don't recommend just welding a steel sheet in that area?

[KB58]

In such situations, if a bulge on a transmission housing doesn't do anything, I'd sometimes cut it off...

[tibimakai]

I have already cut, what I thought that is safe. I don't want to see a hole there.
I should have made the tunnel wider, but it's a bit late for that.

[RTz]

You can sheet it if you want. Everything's a trade off. There is a study floating around that showed considerable increase in chassis strength by sheeting the tunnel, firewall, and rear bulkhead with steel (I think 18ga, if memory serves) I did this with my car and it cost 60+lbs of weight compared to aluminum, but it was a trade off I was willing to make for the strength and added protection if the unspeakable were ever to happen. There's not a right or wrong answer, do what suits you.

[tibimakai]

That is a great looking chassis!
I'm planning to add steel sheet metal only in a few places, like this tunnel "issue" that I have. I may add some tubes as well, if I can.
Aluminum sheet is pretty expensive these days, even steel in not cheap.
Thank you all.

[Driven5]

Here is an original Lotus 7 frame:


Here is an original Locost frame:


Welding steel panels where you can't put diagonals in your tunnel will still be considerably stronger than either of them.

[tibimakai]

Wow, so everything that I will add, it will be stronger than the original.
I feel better now.
Thanks for that.

[rx7locost]

Wow, so everything that I will add, it will be stronger than the original.
I feel better now.
Thanks for that.

Remember that Colin Chapman designed to the minimum. One of his many quotes :

Any car which holds together for a whole race is too heavy.

Using his chassis design as something to strive for is not a necessarily great idea. The Locost chassis with the Aussie mods is much better starting point.