There is a discussion on a message board about the use of O rings in model steam engines. Both the types and where they are, or are not, suitable, together with the advantages /disadvantages of them compared to other forms of seal. What opinions do members here have? Alan MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.