I have finished my 3rd homemade slot car track from MDF. I have sealed it properly all the way.
My first 2 tracks used a cheap latex paint for the track surface. This was when there was a higher rubber content in the cheap latex . The higher the rubber content, the better traction the slot cars get with the urethane tires.
Now after 15 yrs has passed the cheap latex no longer seems to have rubber in it. So I am at a loss as to what to look for in order to get the higher latex content.