Racetrack Terminology Question

[Lessen]

If a turn is stated as a given length, is that it's outside, inside or center line measurement? For instance, Martinsville speedway has a turn length of 588 ft. Is that 588 ft. around the inside perimeter, outside perimenter or halfway between?

 

[jetmechG550]

It's the preferred line, usually the low groove. Remember ol' Harry Gant and how he used to run the high line all the time. I was reading one time that during the 600 at Charlotte when he was running the high line around the top of the track he was actually running about another 14 miles.

 

[Plaidfish]

so do thehy measure it like a parabolic curve within the track width, or do they just use the actual curve of the track?

 

[jetmechG550]

Curve of the track.

 

[Plaidfish]

O-i-c......

 

[Lessen]

interesting. So turns 1 and 2 at darlington are measured by the outside line but turns 3 and 4 are measured by the inside line.

parabolic curve... gotta look that one up.

ohhh, one of those little string art things we all made in grade school.

 

[Plaidfish]

I meant do they measure the line of the drivers or the actual line of the track.......a parabolic curve would mean they measure the line the cars would take.....when you drive a track your car won't follow th etrack line exactly.....it will come in wide from the turn and apex the turn at the most inside point and sweep wide across the lane coming out...that line will actually be longer than the measuring the true curve of the track.......that line will be a parabolic curve.....Jet new what I meant....

 

[Lessen]

I understand what you mean Plaid.

The reason I ask is because I'm playin around with a free trial of TurboCAD and attempting to draw Bristol. I became confused when the measurement they give on the website don't add up.

Bristol is supposed to be .533 mile
Straights are 650 ft.
turns are 910 ft.

but that's actually more like .591 mile if you figure the 910 ft. is taken from the outside of the turns. Then, if 910 ft. is taken from the outside of the straight and swept down to the inside apex (closer the actually drivin line) my rendering is quite off.

I'm also not sure where the changing in the banking begins to shift. I can only assume the straight is 16 deg throughout it's entire length then the inside begins to drop toward 36deg at the beginning of the turn.. not sure where it finally reaches 36deg though... maybe the center of the turn (not between the turns)???

 

[Plaidfish]

you would think the highest bank would be at the apex.....
you are doing a 3D rendering of it???? that's pretty cool...can you send me a copy after you're done??? is it in .dwg or .dxf format...

 

[Lessen]

when I go to open the file it says "TCW-TurboCAD for windows drawing file"

I kinda ignorant to this whole CAD thing cuz I'm just figuring it out as I go, (I'm on vacation so I gotta occupy myself ya know )

 

[Plaidfish]

but what is the file extension? when you look at it in explorer....make sure you don't hide know file type extensions....

 

[Lessen]

ok, I figured it out. I had to un-hide the extensions, but the extension is TCW. probably can't open it w/o TurboCAD.

 

[Plaidfish]

yep, try selecting save as and in the drop down menu on the bottom see if you can save as a .DWG or .DXF.....DXF is a universal format that most Cadd progs deal w/.....

 

[Lessen]

ahhh, that's right. ok, I'll probably mess around with it some more tomorrow.

ok, I was just able to save it as a .dwf and open it in AutoCAD LT.

I thought I couldn't draw in 3 dimension with LT ?? It's only wireframe but it's still drawn in 3d. I let's me rotate it and twist and all that so I guess I could just use AutoCAD... which I prefer anyways. I've been able to teach myself how to use AutoCAD much much quicker than TurboCAD anyways.

 

[Plaidfish]

I believe the ONLY thing LT won't do is auto rendering stuff....if you had to lay out your original and just plot lines in a 3D environment you should be good to go......meaning ACADD LT won't take 2D drawings (orthographic views) and create 3D imaging.......I'm not 100% sure on that but it's how I understood it to be....

 

[Lessen]

yeah, I'm starting to get a better idea of what I can do with LT. seeing as how I can draw wireframes in 3d that pretty much good enough for me. Pretty much it seems like I can draw lines in 3D but It can't render those lines into surfaces and display it as such. That's probably a really rookie sounded understanding but whatever. lol. I'm gonna continue to workon it and send it your way.