velocity: multiple identical partitions

Hi all,

I'm building a design with several instances of a rather complex block.
I'd like to synthesize this block only once and re-use it afterwards, if
possible with identical layout.
I could probably go and make a DEF out of the block, but as I understand,
timing information from within the block would be lost in this step.

So I'm looking instead to make the block a partition, and place this
partition several times. So far I didn't manage to do this. I've searched
the web and found, that the concept seems to be calles "clones", but no
futher information how to do it precisely.

Has somebody done this before and can post a sequence of commands to run?