thinning Schooner varnish

I apologize for seeking info that I know I've seen on the Forum (but after many searches cannot find). Is it essential that one use Interlux's proprietary "333" thinner w/ Schooner or will another product suffice? If so, which products?

 

Greatly appreciate your help,

John

Go to "Varnishing Struggles" on the Forum.  Joey Schott adds a good post.  I am about to begin varnishing, and this query has me a little daunted.  And the answer.  Joey says ditch the 333. 

Many thanks dawnndaves, that post (by Joey Shott) was very helpful.

 

All the best,

John