Such sad news mate, my condolences to you and your family. Sounds like he was an extraordinary man, it's great you have shared so many experiences together and still own some of his original machines.
As a son you feel like your father is invincible and will always be there to bounce ideas and thoughts off but unfortunately one day that ends. I had a reality check a couple of weeks ago when I found out my father has incureable prostate cancer. Like you say spend as much time as you can with your loved ones, and make precious memories, give them a hug and show them how much you love them.