Replace VPI TNT rubber belt with nylon thread

Do both spans. The short length between the motor and the flywheel likes more tension than the platter span. Heavy cotton or poly thread requires a bloodknot; thicker silk requires a loop knot with the knot positioned to travel on the outside of the span. It takes a bit of practice to arrive at the correct tensions, but once there you won't go back.

I own a VPI Scout and my dealer recommended replacing the rubber belt with a silk thread when I was buying it. Since I don't have a speed controller, would you say it'd be pointless to do it and better to stick with the rubber belt?

You can't do it without a speed controller. The different diameter of the string vs belt will result in a major speed difference.

Here's a link to an on-line vendor for inexpensive silk thread in any color you may want. I recommend size or 3.

Griffin Silk Bead Cord. Link below for online supply:
http://www.artbeads.com/stringing-materials-griffin-silk-bead-cord.html

I have an SDS. Thanks for the link!

Can the silk thread be used on a TNT2 with 2 drive belts that only touch 3 points on the platter ?
There was some regular 100% silk in the house. Thin stuff s303. I tried this out of curiosity. I got it to spin but it was too slow even when turning the speed faster with the SDS. Any thoughts?