chain tensioner

Update 11Dec2019: I've put this through 2 cyclocross races and it performed as I hoped by staying in-tact. Since then I've put another 100 miles on it commuting and it is still going strong.

I made this chain tensioner to fit over the chainstay and utilize a chain pulley found here.
https://www.thingiverse.com/thing:2863096
You must print both support sides and use a skate bearing (608) for the pulley. the supports are angled at 8 degrees. It should be placed along the chainstay to line up with the front ring.