I would like to touch-up our white finish line to improve the contrast between the line and the black squares indicating the lanes for our finishlynx system. Any suggestions on paint to use? Someone suggested white shoe-polish. Thoughts?

We use black shoe polish to add/refresh the contrast dots. I have not used white to go the other way. My belief is that you want to be careful of anything high gloss as it will reflect back.

I repaint our line every year. I've used krylon spray paint with pretty good success. I've also used field line paint, the stuff used to paint soccer/football fields.

Because I time at various areas I tend not to repaint the line. I usually take a roll of white duct tape, a roll of white trainers tape, a roll of Black cloth Gaffers tape and a staple gun. If I can set up the camera so that the sun does not get a chance to reflect off of the line the white duct goes down either over the entire line or just the lanes that need refreshing. The trainers tape will go over the duct tape when their is glare. The gaffers tape makes the intersections. If I think that we could get strong shadows the gaffers tape gets pinched so it makes a little "sail" that stands up about 3/4 of an inch. If the track is wet or the forecast is for rain the tapes get stapled with 1/4 or 3/8 staples from the staple gun. I've found that it usually works and I've been doing the line like that since the 80's for ACCUTRAC/Omega OPS and since 93 for Finish Lynx cameras.

The rolls of tape are usually just under 5 cm wide so the line becomes the correct width with one layer. Cutting the gaffers tape in half brings the lane marks close to the 2cm width now in the rule books.

staple gun is a trick I've never seen as sometimes with any moisture it's hard to do - thanks for that

one track we go to likes to use little cardboard squares wrapped in black tape for the intersection lines -- they just lay them out there and they seem to work well -- like your sails they have some depth to them