Can the C3 spool be modified so that it can be spooled with braid without having to back it with mono?

You can always put that small piece of tape that comes with the bread on the spoole

Yes,but why would you want to fill the entire spool with expensive braid when you can back it with really cheap mono?You will never use all of it.I like to buy a 150 yd spool of braid and find the middle and cut it in half.Then I can fill two identical reels with the same amount of braid.

I would still use mono for a backer and if you must fill 100% then Teflon Plumbers Tape makes an excellent backer. In fact if you are fishing really dirty water or salt water and you have a drilled spool I recomend putting plumbers (Teflon) tape on the spool anyhow to keep dirty or salty water from going into the reel by way of the "wiffle" holes in the spool. That is one of the biggest culprits in reel failure in salt water climates that there is.

...to add to this thread...it is my understanding that the mono backing (and tape) is used to help curb the serious digging in of braid backlash....which as some of us have learned the hard way, can be expensive. Sometimes, you just have to cut the line to get it off. That is my understanding on the purpose of having backing on braid. Anyone else want to clarify, correct, or add to that? Thanks.
Steven

I wonder if you might not get better casting results with a full spool. Not sure why you would ever need more than 150-200 feet of braid, though. For distance competitions, perhaps?

With a bad backlash, cutting that stuff off can make a real hole in your day.

The problem is that Braid SLIPS on the spool. If you are not doing one of the above then chances are a lot of your backlash's are a direct result of no backer on the reel. I know that 99% of the reels I get in with the complaint of drag not working or cannot be adjusted is because the braid is slipping on the spool. I say 99% but it is more like 99.99%.

By the way, you casting distance, retrieve rate and a number of other factors are directly based on a full spool of line reqardless of a backer. You can fill it with styrofoam as long as the line edge is within 1/8" of the spool lip.