Exporting secure seed using bitcoin core I am trying to secure my own bitcoin.  

I want to generate a bunch of addresses from a HD Seed, however I am paranoid about the security of any seed generated from any website and so only trust in the bitcoin core client.  

I have downloaded and compiled the bitcoin-core client, but am struggling to understand how to export the seed and or seed + my password.   

Is this feature not available on bitcoin-core and if not is there something else people use to secure large amounts or bitcoin using a HD seed +  custom password.  

My ultimate plan was to then get one of the addresses generated from this seed, plus 2 other addresses from other seeds on other remote machines to then create a multi sig address for securing my bitcoin.  

Any help/input appreciated.
Bitcoin Core uses BIP32, but does not implement BIP39 - As such, you cannot export a set of seed words, since the seed to BIP32 master key conversions is one way only, and it is not possible to obtain seed words if you only have the master key.

You should simply back up the master key itself, and import it into another instance of bitcoin core when needed. The dumpwallet command will help you with that.