Investor Engineering Discussions

[MC3OZ]

Please explain further, aren't those loads primarily concentrated in the rear axle assembly?
Center structure handles pitch torque and center loads. Towing should be mainly inline other than tongue weight. Payload in bed should be mainly vertical.

I might be wrong, but I think that the Cybertruck sides are part of the reason why it doesn't need a heavy ladder frame.

The truss-like shape helps hold the vechicle together when towing forces put a lot of load on the rear end. Maybe this isn't as significant as I think it is, I ment to convey contributing rather than primary.

If the CT can match the performance of a body-on-frame in a lighter unibody design that is a big step forward. Corey did have some doubts on CT towing.

 

[mongo]

I might be wrong, but I think that the Cybertruck sides are part of the reason why it doesn't need a heavy ladder frame.

The truss-like shape helps hold the vechicle together when towing forces put a lot of load on the rear end. Maybe this isn't as significant as I think it is, I ment to convey contributing rather than primary.

If the CT can match the performance of a body-on-frame in a lighter unibody design that is a big step forward. Corey did have some doubts CT towing.

Yah, the triangle boosts fore/aft rigidity and stability during driving dynamics. Especially compared to a traditional low height ladder frame. Taller cross-section=less material for same or better performance, like a truss bridge versus I-beam span.

I'm just thinking the main tow load path is carried on the lower chassis anyway so the triangle isn't so helpful with that. Unless there is a lot of tongue load or bed load offset from the axle which is partly transfered to the front axle (fore/aft bending).

 

[mongo]

Structural pack is design to work with the added rigidity from front and rear castings. The 3 doesn't have those. This is not a 4680 pack.

Hum?
The 4680 Y is designed to mate to the cast front, but isn’t a structural pack better mechanically than 2170? If so, why would it need to rely on castings?
Differential: could Tesla replace a 2170 pack with a non-structural 4680 pack? If so, why not a structural 4680?

 

[bkp_duke]

Hum?
The 4680 Y is designed to mate to the cast front, but isn’t a structural pack better mechanically than 2170? If so, why would it need to rely on castings?
Differential: could Tesla replace a 2170 pack with a non-structural 4680 pack? If so, why not a structural 4680?

I didn't say "rely". Yes, Tesla could chose to install a 4680 pack, but they have said it is something they are only going to do with casts.

Current 3 is not getting a structural pack, especially when Drew and Elon are saying the current structural pack is essentially "version A" and they want to incorporate additional refinements.


You are talking theory, I'm talking practicality.

 

[mongo]

I didn't say "rely". Yes, Tesla could chose to install a 4680 pack, but they have said it is something they are only going to do with casts.

Current 3 is not getting a structural pack, especially when Drew and Elon are saying the current structural pack is essentially "version A" and they want to incorporate additional refinements.


You are talking theory, I'm talking practicality.

Those are valid points, but I was referring to "Structural pack is design to work with the added rigidity from front and rear castings".

In future iterations, the chassis/ stuctural pack will more rely on each other, but (at least currently) a structural pack places less ridgitiy requirements on the chassis than a non structural pack does.

 

[bkp_duke]

Those are valid points, but I was referring to "Structural pack is design to work with the added rigidity from front and rear castings".

In future iterations, the chassis/ stuctural pack will more rely on each other, but (at least currently) a structural pack places less ridgitiy requirements on the chassis than a non structural pack does.

FYI - currently you can't plug a structural pack (4680) into a Model 3. They don't "fit". Mounting points, etc. are different because of the pack top being part of the floor (and there are other differences).

Sure, you could design a 4680 pack specific for the current non-cast 3, but Tesla isn't going to do that until casts are ready and the pack can be universal between 3 and Y (hopefully Highland, but we do not have confirmation on this).

 

[Buckminster]

https://twitter.com/x/status/1653774109896069128

 

[Buckminster]

Could gen 3 use aluminium wiring?

https://twitter.com/x/status/1654799430791430146

 

[Oil4AsphaultOnly]

Could gen 3 use aluminium wiring?

https://twitter.com/x/status/1654799430791430146

I'm not buying his argument. The largest use of copper is in building construction according to the USGS: Copper Statistics and Information | U.S. Geological Survey

PEX can replace copper in the plumbing (but that's not what the tweet was addressing), but there are fire risks associated with aluminium wiring in homes, so I don't see that happening anytime soon. There are more copper in the plumbing than in the wiring anyway. So yes, the scarcity of copper isn't a roadblock to transitioning to renewable energy, but replacing copper wiring isn't the best way to achieve it.

 

[Buckminster]

https://twitter.com/x/status/1654906092302860288

 

[MC3OZ]

From that Twitter thread on Aluminium:-

CastCoil: high-performance aluminium coils for electric drives through new casting technology​

 

[Dikkie Dik]

but there are fire risks associated with aluminium wiring in homes

Answered in that thread and blogpost. Bad practice to mix aluminium wiring with receptacles and connectors suited for copper, not aluminium.

https://twitter.com/x/status/1654830973375086592

Aluminium is already replacing HV cabling where the advantages are less weight and cost.

 

[JRP3]

Yes high voltage mains and the feed into your house are aluminum. There are also combination cables that use aluminum core and copper outer. Copper-clad aluminium wire - Wikipedia

 

[navguy12]

Answered in that thread and blogpost. Bad practice to mix aluminium wiring with receptacles and connectors suited for copper, not aluminium.

https://twitter.com/x/status/1654830973375086592

Aluminium is already replacing HV cabling where the advantages are less weight and cost.

When I wired my first self built house in 1991, I learned then that all the wire in the grid was aluminum, including the triple 0 guage that came into the circuit breaker panel from the meter base.

As long as the lugs were torqued to spec AND the correct anti oxidant paste was used, aluminum posed no safety issues.

 

[bkp_duke]

Yes high voltage mains and the feed into your house are aluminum. There are also combination cables that use aluminum core and copper outer. Copper-clad aluminium wire - Wikipedia

Not in our house. 400A input (200 x 2) and they are some very beefy Copper cables. Laid eyes on them multiple times when the solar and powerwalls were installed.

 

[mongo]

Not in our house. 400A input (200 x 2) and they are some very beefy Copper cables. Laid eyes on them multiple times when the solar and powerwalls were installed.

Are you talking pre or post meter?
I think "Feed into your house" was referring to power company domain. Anything after meter is builder's.

 

[bkp_duke]

Are you talking pre or post meter?
I think "Feed into your house" was referring to power company domain. Anything after meter is builder's.

Pre meter.

 

[JRP3]

Maybe above a certain current level the cable size becomes too large in aluminum so it's worth using copper. The only large size copper I've seen in residential is the ground loop.

 

[BioSehnsucht]

For certain eras of construction, aluminum was common, but it lead to a lot of fires due to mixing of materials (i.e. switches and outlets were still copper), and the resulting effects of that. There are certain situations where it's not a problem (especially those in which you can control the materials end to end, to prevent that being an issue), but generally aluminum is considered an inferior and unsafe replacement for copper. It's even looked down upon in the IT world, with cheaper network cables being copper clad aluminum, and the good ones being pure copper.

 

[Buckminster]