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Author Topic: Track marks and our use of 10ft  (Read 17558 times)

Offline llama of death

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Re: Track marks and our use of 10ft
« Reply #15 on: August 26, 2016, 11:20:12 pm »
I love you dearly but your answer did not have the length. <3 What is the full length of the center line as measured from the inside line? How many feet long is it? The circumference.
"As measured from the inside line?"
I can't make sense of that part of your question.

The circumference? What good does that number do? I suppose if you wanted to do a really really rough est of the number of times one could cut the Cir into 10ft sections... kk, the circumference of the true center of track is 66.3175 feet.
I play devils advocate a lot, it is always because I desire a complete understanding of the rule/scenario. I do make changes to my reffing often as a direct result of discussions resulting in a consensus. Particularly if it is contrary to my previous understanding.

Offline Vanilla VICE

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Re: Track marks and our use of 10ft
« Reply #16 on: August 29, 2016, 05:22:57 pm »
Maybe I'm not asking the correct things. In the old appendix A for the track diagram it told you the length of the outside and inside track boundary.  I wanted to know what the approximate length would be if u added a "middle track boundary" or "center track boundary"

Length of the inside boundary = some number around 128 feet
Length of the outside boundary = some number around 256 feet
Length of the "center track boundary" (if one existed) =  ? Its some number around 180 feet I would guess (18 sections of 10 feet), but I just wanted to know what it was.
Muscogee Roller Girls: Columbus, GA
FlatTrackStats Mod

Offline llama of death

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Re: Track marks and our use of 10ft
« Reply #17 on: August 29, 2016, 07:17:36 pm »
Maybe I'm not asking the correct things. In the old appendix A for the track diagram it told you the length of the outside and inside track boundary.  I wanted to know what the approximate length would be if u added a "middle track boundary" or "center track boundary"

Length of the inside boundary = some number around 128 feet
Length of the outside boundary = some number around 256 feet
Length of the "center track boundary" (if one existed) =  ? Its some number around 180 feet I would guess (18 sections of 10 feet), but I just wanted to know what it was.

C=2*Pie*R
The corner is ~a half circle we can estimate to prove my number is accurate by deving the C by 2.

R=19.5 ft

C=122.52
C/2= 61.26

And as you pointed out before there is a overage into the straight to account for of ~5 ft so my numbers of ~66ft is accurate.

Btw, the inside is 39.2699 ft and the outside is 86.2775. I am not sure where you pulled 128 ft from but that may be referencing the total perimeter of the track, as in how much rope you need.
I play devils advocate a lot, it is always because I desire a complete understanding of the rule/scenario. I do make changes to my reffing often as a direct result of discussions resulting in a consensus. Particularly if it is contrary to my previous understanding.

Offline Vanilla VICE

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Re: Track marks and our use of 10ft
« Reply #18 on: August 29, 2016, 07:33:38 pm »
I'm looking for the length of the perimeter of the metaphorical center track line. I'm going to keep figuring out different ways to ask this until there is some number around 180 feet as your answer lol

GH mentioned this number wasn't divisible by 10, so I want to know what the number actually is.
« Last Edit: August 29, 2016, 07:44:53 pm by Vanilla VICE »
Muscogee Roller Girls: Columbus, GA
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Offline llama of death

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Re: Track marks and our use of 10ft
« Reply #19 on: August 29, 2016, 08:22:28 pm »
I'm looking for the length of the perimeter of the metaphorical center track line. I'm going to keep figuring out different ways to ask this until there is some number around 180 feet as your answer lol

GH mentioned this number wasn't divisible by 10, so I want to know what the number actually is.

As in a full lap distance? As skated down the middle of the track? That would be 192.5ft.
I play devils advocate a lot, it is always because I desire a complete understanding of the rule/scenario. I do make changes to my reffing often as a direct result of discussions resulting in a consensus. Particularly if it is contrary to my previous understanding.

Offline Vanilla VICE

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Re: Track marks and our use of 10ft
« Reply #20 on: August 29, 2016, 08:45:46 pm »
I'm looking for the length of the perimeter of the metaphorical center track line. I'm going to keep figuring out different ways to ask this until there is some number around 180 feet as your answer lol

GH mentioned this number wasn't divisible by 10, so I want to know what the number actually is.

As in a full lap distance? As skated down the middle of the track? That would be 192.5ft.

Winner winner winner.
Muscogee Roller Girls: Columbus, GA
FlatTrackStats Mod

Offline llama of death

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Re: Track marks and our use of 10ft
« Reply #21 on: August 29, 2016, 11:59:28 pm »
I'm looking for the length of the perimeter of the metaphorical center track line. I'm going to keep figuring out different ways to ask this until there is some number around 180 feet as your answer lol

GH mentioned this number wasn't divisible by 10, so I want to know what the number actually is.

As in a full lap distance? As skated down the middle of the track? That would be 192.5ft.

Winner winner winner.

Still not sure why that is more relevant (or easy to use to arrive at an accurate layout) than the measurement of the corner arc length alone; nor better than setting an array of 10ft circles with centers along an arc with common center point and no defined radius, then simply choose how many 10ft radius circles one wants to span the arc length.

Anyway, in the end there are a few ways to set 10ft marks listed here which achieve more or less the desired reflection of the rules and are easy to layout repeatably.

Let me know if any of you test them out and have thoughts on their viability. (My home league is allowing me to Alpha test them on our track to get some initial opinions about them)
I play devils advocate a lot, it is always because I desire a complete understanding of the rule/scenario. I do make changes to my reffing often as a direct result of discussions resulting in a consensus. Particularly if it is contrary to my previous understanding.

Offline Vanilla VICE

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Re: Track marks and our use of 10ft
« Reply #22 on: August 31, 2016, 03:27:29 pm »
Probably because you're trying to solve problems and I'm just barely at the point of understanding what the problem is.  8)  You're trying to find a reason why I would want to know, there isn't one. I was just curious what it was.
« Last Edit: August 31, 2016, 03:31:34 pm by Vanilla VICE »
Muscogee Roller Girls: Columbus, GA
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Offline The Sharmanator

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Re: Track marks and our use of 10ft
« Reply #23 on: September 03, 2016, 01:15:57 am »
I think a DME Arc would work

Offline General Hellativity

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Re: Track marks and our use of 10ft
« Reply #24 on: September 03, 2016, 12:11:30 pm »
I think a DME Arc would work


No, because technically it can't be intercepted anywhere but the IAF. ;)

Offline Stony Hawk

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Re: Track marks and our use of 10ft
« Reply #25 on: September 04, 2016, 03:21:49 am »
Llama,

I have autocad but not sure how to post cad images here.  Try this configuration on your side.  It demonstrates how the 10' marks are exactly created with the current published method

Draw out the track boundaries in the usual way and use the standard 84.5" array to plot the track marks through the inside track boundary.  This gives the 5 segments in the curve and one polysegment as we exit the curve and enter the straight.

Next:  from the center point, draw an arc with a radius of 210.05" (17"-6.05").  The arc length will be 660" in the curve.  The 5' of the straight adds another 60".  This gives us a total arc/line length of 720".  As long as this total length is divided equally, we will end up with six segments that are 120" each (as measured by the arc length)

This what the 7' 1/2" measurement does.  The angle of the first five segments will be 32.719 degrees.  The last partial segment will be 16.403 degrees.

(At the R210.05 arc line). If you look at the arc length in each segment, it will be exactly 120" (10').  The last segment will consist of an arc length of 60" and a straight length of 60".  So the last poly segment is also exactly 120" (10')

I'll try to figure out how to post the cad image.

So, it's true that radius line I mentioned is not near the center of the track.  It's ~5' from the inside track boundary.  But, we at least have exactly 10' apart for each segment for at least one symmetrical distance from the inside track boundary.

Let me know if I can clarify in any way.

Offline Stony Hawk

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Re: Track marks and our use of 10ft
« Reply #26 on: September 04, 2016, 03:15:10 pm »
Here is the cad drawing to go with the previous post


Offline llama of death

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Re: Track marks and our use of 10ft
« Reply #27 on: September 06, 2016, 05:20:34 am »
Here is the cad drawing to go with the previous post

I will have chance to get to this in the next few days but there is a inconsistency from wftda outline to the drawing you provided. Note I have not reproduced your described method but the error is visable seen.

They says "...placed alongt the line of   the string in the middle of the track..."

There is a major difference between your drawing which uses a constant radius of 17ft 6. A constant radius sharing the same center point as the inside line cannot create marks which are center to the track. The track boudary lines do not share a center point so an arc through the center must have its center at the midpoint of the line between the two.

I will try and get around to retracing your description later but I can tell you it does not represent a standard wftda layout.
I play devils advocate a lot, it is always because I desire a complete understanding of the rule/scenario. I do make changes to my reffing often as a direct result of discussions resulting in a consensus. Particularly if it is contrary to my previous understanding.

Offline Stony Hawk

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Re: Track marks and our use of 10ft
« Reply #28 on: September 06, 2016, 03:06:51 pm »
Llama,

Until I read your post, I took the below language from the WFTDA Track Layout guide at face value and never checked it.

     “a 1-2 foot (or 0.30-0.60 meter) tape marker can be placed along the line of the string in the middle of the track, and these tape markers will measure 10 feet (or 3.05 meters) from each other along the track.”

As both our measurements demonstrate, this statement is absolutely not accurate.   

My drawing only uses the standard layout in that I am still using 7’ ½” distance to plot the radial marks on the inside track boundary.   In order to get the marks to be 10’ from each other, my calculations indicate that these marks should 5’ from the inside track boundary and not ‘in the middle’ of the track as the guide indicates.

So, one question that I have is why does the official layout guide make this false statement?   

Second question, does anyone have a problem with altering the official method to actually plot these marks 5’ from the inside track boundary as opposed to the middle of the track?

Also, how did you get your image to imbed in your post rather than appear as an attachment


Offline Stray Taco

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Re: Track marks and our use of 10ft
« Reply #29 on: September 06, 2016, 03:38:07 pm »
Llama,

Until I read your post, I took the below language from the WFTDA Track Layout guide at face value and never checked it.

     “a 1-2 foot (or 0.30-0.60 meter) tape marker can be placed along the line of the string in the middle of the track, and these tape markers will measure 10 feet (or 3.05 meters) from each other along the track.”

As both our measurements demonstrate, this statement is absolutely not accurate.   

My drawing only uses the standard layout in that I am still using 7’ ½” distance to plot the radial marks on the inside track boundary.   In order to get the marks to be 10’ from each other, my calculations indicate that these marks should 5’ from the inside track boundary and not ‘in the middle’ of the track as the guide indicates.

So, one question that I have is why does the official layout guide make this false statement?   

Second question, does anyone have a problem with altering the official method to actually plot these marks 5’ from the inside track boundary as opposed to the middle of the track?

Also, how did you get your image to imbed in your post rather than appear as an attachment

I'm not knowledgeable of CAD, but from the posted picture, one thing I noticed was that it was 10-foot arcs, which is different from two lines that are ten feet apart.

My understanding of pack definition is that it's determined by straight-line distance, even around the apex (as in a straight line run from the tangent of the inside boundary where the Skaters are.

[rule]3.1.2.1 - Distances for determining the pack and the Engagement Zone are measured as the shortest distance parallel to the inside track boundary between Skaters’ hips (see Section 10 - Glossary for Hips).[/rule]

And there is the rub, and why the 10-foot markers are nothing but a guide and not definitive.
Mike "Stray Taco" Straw

I know some things, but there's a lot more I don't know.

 

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