[Inderjit Sanghera]

I think that there is a quote in the Silmarillion that may imply that Morgoth went along trying to create new races after he realised that Orcs just wouldn't do in a war with the Noldor.

"... for Morgoth percieved now that Orcs unaided were no match for the Noldor; and he sought in his heart for new counsel"

The Silmarillion; Of The Return Of The Noldor

And underneath that it tells of the coming of Glaurung.

In BoLT, in the Fall of Gondolin, there were some mechanical dragons,made my Morgoth at the request of Maeglin and I think that it may mention that Morgoth made 'normal' dragons, but I can't remember. Though it shouldn't be taken into the Silmarillion legendarium.