To build a big frickin’ spaceship, you need a big frickin’ rack to put it on. And SpaceX has the rack.

The company’s billionaire CEO, Elon Musk, took to Instagram tonight to show off the main-body construction tool — which is analogous to the turning mandrel tool that Boeing uses as a rack for a 787 composite fuselage while it’s being built up from layers of carbon fiber.

A Tesla Model 3 electric car is included in the picture to lend a sense of scale:

For what it’s worth, some have speculated that SpaceX’s partner for BFR carbon-fiber construction is Janicki Industries, which is headquartered in Sedro-Woolley, Wash.

The BFR interplanetary spaceship is the cargo-carrying element of the reusable Big Frickin’ Rocket that Musk eventually plans to use as an all-purpose space vehicle — for trips ranging from point-to-point suborbital passenger travel, to orbital satellite deployment, to moon missions, to journeys to Mars and beyond.

Last month, Musk said the spaceship is already under construction and should be on track to start short-hop test flights next year.

SpaceX’s tentative specs suggest the spaceship will be 30 feet in diameter and about 157 feet long. The craft is meant to accommodate about 100 people in 40 cabins when it’s configured for Mars trips. Musk said the first, uncrewed BFR cargo mission to the Red Planet could take place as early as 2022.

The other main element of the BFR is the booster, which is projected to be even taller than the spaceship. The current design incorporates 31 methane-powered Raptor engines, capable of providing a record-high 11 million pounds of thrust at liftoff.

Will SpaceX stick to the schedule for Mars flights? If history is any guide, it’ll take longer than Musk expects for the BFR to spread its wings, but as long as he has the wherewithal — and Musk’s net worth is currently estimated at $19.6 billion — he’ll stick with it.

The fact that Musk is showing off his giant tool demonstrates that he’s serious.

Update for 11 a.m. PT April 10: Teslarati reports that photos taken outside SpaceX’s facility at the Port of Los Angeles in San Pedro, Calif., show tools from Ascent Aerospace Coast Composites — which implies Ascent is a supplier for the BFR construction operation. A spokeswoman for Ascent Aerospace declined to comment on the SpaceX connection when contacted by GeekWire.