Montacute I almost choked on my cup of tea! He said it so seriously.
Thank you all for your suggestions.
My Dad's name is actually Robert but he LOATHES it. His middle name is Francis - which he also hates (and, quite frankly, so do I). He's very vehemently just 'Bob' so that's why it has to be a variance of 'Bob', if we can find one.
His mum is Francis June, but she hates her first name so much that she goes by her middle name - although she still decided to pass it onto her son! 
2014newme That's sort of why I was asking for suggestions to see if it can be done nicely 
Ilovechocolate111 Ding ding - I think we have a winner! Bobbin would fit quite nicely with my mum's obsession with sewing too, come to think of it, but it would have to be June Bobbin - 'Bobbin June' sounds too much like a nickname for the village bike 
BUT, after all this - this morning I told my DH that I preferred June Bobbin as middle names and he point blank refused. I pointed out that he'd suggested June-Bob. He stared at me for a long moment.
"I can't believe you thought I was serious," he said.
Cue much spluttering and outrage from me. He said it was a stupid name for a middle name (Bobbin, not June) and I pointed out all of the reasons HE gave ME when we had the 'June-Bob' discussion - nobody ever introduces themselves with their middle name, it will only be on official documents etc etc.
Then I smiled sweetly. "Well, that's just tough because it's happening."
"No it isn't." He sniffed. "We're having a boy anyway."
He's such an arse.