Question on these,
Do you use both together?
My fireplace had andirons but i just bought a grate cause my thinking is if you place logs on the andiron, they will eventually drop to the fireplace floor when they burn out. At least if they are in a grate, they will just sit there and burn without dropping. Not sure what is the correct usage as i am new to fireplaces . Any help clearing this up is appreciated

Grate:


Andiron:

 

You have your usages right. As for which one to use, it's personal preference. Logs will fall through both eventually, but sooner through the andirons. Once the logs fall to the ground, air can no longer get under the them...less air circulation = less ideal burning = more smoke. An advantage of andirons would be that you can adjust how far apart they are to suit the length of your logs. Personally, I'd go with the grate.