Hi Guys,
As I go about trying to tune my Mattel plastic track (see another thread), I discovered that the slot width is not consistant. Without taking out the feeler guages just yet (only way I can think of to measure the slot width), I took some old credit card type plastic cards and tried to see how many could fit into a slot. Some pieces took three, while others could only manage two. Sometimes, the slot width varies within the same piece. I would think that's got to be a difference of at least 1/32".

It seems some pieces have narrower slots than others. I seem to notice the 6" straight and 12" curve are the narrowest, while the 9" straight and 9" 1/8 curve are a bit larger. Some 9" straights are much (relatively speaking) larger.

I have been thinking about putting a round bit into my Dremel and going around the track to open up the narrowest slots just slightly. I find the bit that fits into a 9" straight (with some wiggle room) and run that around the track to open up the narrowest slots. It should only take a few minutes.

I seem to notice that some cars seem to drag around certain curves as if the guide pin binds in the slot. Opening up the slot just a hair should improve that.

Comments?

Thanks...Joe

Could the sloppy gapping in the 9" curves and 9"straights be due to the molds wearing out faster from more use?

Seems every Tyco / Mattel set through the years has been mandated to have an overabundance of those particular pieces.

Is the terminal track sloppy too?

I'd just take the pin out of a car and see if it actually does bind in the suspect areas. If not, it's not gonna make any improvement, in fact if whatever method you use leaves a rough surface it might make it worse. Simple physics pretty much mandates that our little non-steering cars will drag in corners, the guide pin is being pushed towards the center of a circle by the sides of the slot.

One thing that does cause binding is a soft and/or uneven table surface, if the track is pulled down too hard in the center the slots will get narrow at the surface.

I had a 15" r tomy curve that was tight. Took me a while to figure out what was going on. Cars would stop. Thought it was a bad electrical connection. Finally just pushed a car around and felt it slow down. Replaced it, all was well.....