Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

I found that 7 mm, while slightly larger than the original, could be fit after doing a real good clean out of residue on the site glass parts.
Bob, my Marklins may have been a little newer than yours.

 Hi Gil, I never had this problem before that I recall ? When I ordered glass I bought two different brands thinking one might be a little smaller. I ordered 1mm standard wall thickness which helped as my older glass tube must have had a thicker wall, 1.5mm ?