Here's a question out of the blue.

Does anyone know if sac replacement on the Delta Colosseum is any more complicated than on vintage pens. (It does not need to go back to the factory or anything like that does it?)

If you just bought it I would send it back personally. I have never replaced a sac on a new pen myself but maybe someone in the "Repair" forum could help.

I've had to replace the sacs on both my Delta Native American and Masai lever fillers. The sacs they came with were unusually thin. It was no different from a vintage pen, just a little heat and the section slid right off. One had a thin metalic foil shim wrapped around the nipple of the section to hold it in place, but when I reinserted it after the sac replacement it held on just fine.

I debated sending it back, but since I had the sacs on hand it was significantly easier to replace than to box up and send back.

If you've replaced sacs on a lever filler before it should be a piece of cake!

Good luck.

Tom Scott