Hi @bwsmedia
If there’s nothing else on your page that modifies the $post
global variable, you should be able to do it like this:
global $post;
the_field('custom_field_name', $post->ID);
This page should give you more idea about it: http://wordpress.stackexchange.com/questions/170358/when-to-use-global-post-and-other-global-variables.
I hope this helps 🙂