Customers will finally get behind the wheels of Model 3 cars Friday as Tesla tries to veer from its high-end image with a more affordable electric car.

Tesla founder and boss Elon Musk planned to mark the occasion with a ceremony at the company's plant in the city of Fremont near San Francisco.

An initial batch of 30 Model 3 cars was expected to go mainly to Tesla employees. Production of the electric car aimed at the broader market - with a price of $35,000 - will ramp up quickly, Musk said, with 100 in August and 1,500 or more in September.

Tesla aims to produce 5,000 units of the Model 3 a week this year, and 10,000 units a week in 2018. The mid-range model is a crucial piece of Musk's ambitions to transform Tesla into a large-scale vehicle manufacturer. It will allow the firm, started in 2003, to produce about 500,000 vehicles in 2018 and a million by 2020.