My understanding was that the Assembly line 2 was designed to transition to producing both S and X and this transition would free up the space of assembly line 1 to be used with Model 3. The much heavier use of robots on Assembly Line 2 is necessary to allow both S and X to be produced at suitable speed on the same line.
One of Tesla's early "innovations", was that the robots would change the tools, so you could have one robot performing 3-5 different tasks, like welding or installing glass. But changing tools takes time, so I think they are now prepared to pay more to save the time needed to change tool heads.
In addition to the fact that Body Line 1 is designed to handle less complex Model S, while Body Line 2 - both more complex MX and MS, as noted by Papafox, Line 2 has capacity of 2500 cars per week, while Line 1 has capacity of about 1200 cars a week.
Another interesting thing is that a while ago some analysts were speculating that if required, based on demand projections, Tesla could keep both Body Lines in operation, while increasing the throughput of the General Assembly line from about matching the throughput of Body Line 2 to matching Body Line 2 + 1.
The significant new information from the article is that Production of MS body-in-white was not blended into Body Line 2 yet. I think that such blending could require some slowdown for debugging the process. Hopefully Tesla would be able to build some extra bodies-in-white as a buffer prior to blending MS production onto Body Line 2.
Line 1 + line 2 = 1200+ 2500= 3700 units
Is that feasible , or is there another constraining isssue ?
Is the feed into these lines a constraint factor?
Frankly I don't know much about the manufacturing.
Anybody better informed please explain.
Here is the deal with the factory folks.
Line 1: few robots, with lots of tool changes. Cheap line to deploy when TSLA was a baby. Makes model S exclusively, and relatively slowly.
Line 2: More robots with fewer tool changes required. Designed to do both X and S but I think has only ever done X.
Line 3: will be built where they warehouse now.
(source: recent factory tours)
Stamping has hugely excess capacity
Paintshop 2 has 500k/yr capacity. I actually think that paintshop 2 was an addition to the original paintshop by the way. I think there is a mothballed paintshop 1 of some capacity.
Final assembly is combined X and S, and appears to be the limiter of the whole factory (or they really are selling to a capped demand). After that is QC prep and delivery which for all we know is at capacity--- I often wonder about this forgotten factory step.
Here is a rough, rough, rough, not-to-scale sketch of the Fremont factory. There is a long strip in front of the factory that is used for storage, and line 1 and 2 are behind them:
(I may have 1 and 2 swapped, but 2 is bigger than 1). the "storage" place is where the line for model 3 is supposed to go. I didn't get a straight answer if M3 will have it's own assembly line but it HAS to. nothing else makes sense.
Here is a crude model of the factory throughput, based on what I understand:
So the stamping is more or less ok for M3. Paint is more or less ok for M3. Final assembly limits the current production. I was told (and MF Daniel too) that the warehouse space will be the M3 line. However, note that if BIW line 2 really can do a high capacity of S/X they can retire the line #1. I have seen a lot of people write on this forum that that is the plan but Tesla has never said that. However it makes sense... they could actually redeploy some of the BIW line robots/equipment into the line 3 seemingly without impacting anything. However, I think the BIW line #2 is really just for X and only theoretically can do the S. And I think TM really wants to make the M3 line from scratch to incorporate all the best learning from the other lines.
Also, they have a whole upstairs that they use for light manufacturing like circuit boards. That stuff could be offshored if needed. They just have the space so they are using it.
Edit: Daniel's article highly implies there will be seperate M3 final assembly line so probably not a mystery.
