Mechanism for reaction of an allene with the Grignard Reagent(RMgX)

How does the Grignard Reagent($\ce{RMgX}$) react with an allene $\ce{CH\_2=C=CH\_2}$ and what are the products formed?


This is exactly what I tried to do.


[![Reaction mechanism](https://i.stack.imgur.com/9xb3N.png)](https://i.stack.imgur.com/9xb3N.png)


Any help will be appreciated.


