In case you didn't see my other post...

"I grew up bowfishing with my Dad's old Bear brushbow that had a 20 year old homemade drum on it.
It was basically a 1" x 4" board mounted to a 1" x 1/2" board that was taped to the front of the bow.
It had an aluminum tab nailed to the side of it to grab the end of the string. Worked great, lasted a LONG time, and cost about 25 cents."