Brocklehurst said the trains were still running, with the damage only affecting infrastructure, such as the points.
However, he said the batteries that powered the trains could not be charged.
In a post on social media, Brocklehurst said the incident was the third case of vandalism in the last two months.
He said each incident had left volunteers “more devastated, more exhausted, and more heartbroken than the last”.
“To see something built with love, care, and community spirit treated with such disregard is incredibly painful,” he said.
Brocklehurst said he had spoken to West Yorkshire Police on Sunday and since the incident had received “such a wealth of support from the local community”, with local businesses also offering to install security cameras.
“It’s cheered us up no end, it’s quite humbling,” he said.