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Can someone please help me with some math Locked

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  • Member since
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  • From: East central Missouri
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Can someone please help me with some math
Posted by Santa Fe all the way! on Sunday, July 9, 2017 11:37 PM

Can someone please tell me what the diameter of a circle of this track would be? I have 24" deep benchwork, would it fit? 

This is a Peco ST-412 HOn30 Setrack Curved Track. #1 9 22.8cm Radius, 45 Degree Sections, Double Sections pkg(4)

Come on CMW, make a '41-'46 Chevy school bus!
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Posted by Anonymous on Monday, July 10, 2017 12:15 AM

24 inches equal 61cm. A 22.8cm radius curve has a diameter of 45.6cm, measured from track center to track center. Add about 3cm to each side and you have an outside diameter of 51.6cm, leaving you with 4.7cm on each side of the curve. That´s sufficient!

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Posted by Santa Fe all the way! on Monday, July 10, 2017 1:08 AM

Thank you Ulrich! The metric system threw me off. 

Come on CMW, make a '41-'46 Chevy school bus!
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Posted by Anonymous on Monday, July 10, 2017 2:04 AM

Santa Fe all the way!

Thank you Ulrich! The metric system threw me off. 

I grew up with it, so it is a no-brainer for me. OTOH, I find it difficult to get by with the measurements you folks in the US use, especially when talking about weight and liquids.

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Posted by peahrens on Monday, July 10, 2017 8:55 AM

Sir Madog
 
Santa Fe all the way!

Thank you Ulrich! The metric system threw me off. 

 

 

I grew up with it, so it is a no-brainer for me. OTOH, I find it difficult to get by with the measurements you folks in the US use, especially when talking about weight and liquids.

 

Ulrich, the good news is your petrol is less expensive.  When ours is $4, yours is usually about $2.  What a deal!  Of course, we get a bit more. Big Smile

Paul

Modeling HO with a transition era UP bent

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Posted by Anonymous on Monday, July 10, 2017 9:06 AM

peahrens
Ulrich, the good news is your petrol is less expensive. When ours is $4, yours is usually about $2. What a deal! Of course, we get a bit more.

3.785411784 times as much, to be precise!

Will the US ever adopt the international metric standards? I have my doubts, despite all the talk about globalization and "free" trade.

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  • From: OH
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Posted by BRAKIE on Monday, July 10, 2017 9:08 AM

Sir Madog

24 inches equal 61cm. A 22.8cm radius curve has a diameter of 45.6cm, measured from track center to track center. Add about 3cm to each side and you have an outside diameter of 51.6cm, leaving you with 4.7cm on each side of the curve. That´s sufficient!

 

Ulrich,That's all Geek Geeked Speak or maybe more like Algebra to me because I've dealt with inches and feet all my life.Surprise

I  never could understand all that cm stuff.Huh?

Larry

Conductor.

Summerset Ry.


"Stay Alert, Don't get hurt  Safety First!"

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Posted by G Paine on Monday, July 10, 2017 9:47 AM

Sir Madog
I find it difficult to get by with the measurements you folks in the US use, especially when talking about weight and liquids

When I worked in the Middle East, I had to do a lot of conversions. I think of it as grocery store metrics:

One kilogram = 2 pounds

1 liter = 1 quart

1 kilometer = 0.6 mile

2.5 centimeters = 1 inch

Not exact, but close enough to buy the correct amount of meat and cheese at the deli counter. Temperature conversion is another thing; why Farinhight choose the feezing point of Baltic Sea water for zero degrees has no logic, except that he was a sea captain who had ships in that body of water - no quick estimates for that one!

George In Midcoast Maine, 'bout halfway up the Rockland branch 

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Posted by Anonymous on Monday, July 10, 2017 9:55 AM

G Paine
Farinhight

You made him British Smile, Wink & Grin,

Daniel Gabriel Fahrenheit was born in Danzig/Germany on May 24th, 1688, son of Daniel and Concordia Fahrenheit.

 

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Posted by DSchmitt on Monday, July 10, 2017 11:19 AM

I worked for a State highway department Enroachment Permit branch during the changeover to metric. The State made the conversion more compliated by trying to make it easier.  There were "soft conversions" (approximate) of English system measurements to Metric system measurements and "hard conversions" (accurate).  

Part of my job was entiering the Post Kilometer (PK) of existing Encroachments into the Permit data base. This was the relatively easy part. I knew to use hard conversions.

I also wrote Permits for new, modified and relocated non-State features being done as part of Highway projects. Durning the design process the Right of Way branch coordinated with Design and negotiated with the Encroachment owners.  They would then send the location information PK to me to write the Permit. Unfortunately they usually sent me soft conversion PK's  which were usually way off the actual location. They were not engineers, were often working from existing information especially early in the process, and most didn't understand the need for accuracy. 

I worked with project plans (usually incomplete), existing plans (English system) and the info sent from R/W to determine the correct PK's and still sometimes goofed. 

With a base of over 100 years of non-metric plans and data there were also blunders made by the designers.

I tried to sell my two cents worth, but no one would give me a plug nickel for it.

I don't have a leg to stand on.

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Posted by bearman on Monday, July 10, 2017 11:25 AM

Ulrich, the answer to adoption of the metric system is no.  Years ago some of the engineering societies insisted that text books use the metric system.  It was an absolute failure.

Bear "It's all about having fun."

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Posted by Anonymous on Monday, July 10, 2017 12:21 PM

My question was one of those that don´t require an answer. I am absolutely aware of the reluctancy to abolish the rather medieval system and adopt the metric system as it is used by the rest of the world.

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Posted by Steven Otte on Monday, July 10, 2017 1:19 PM

The OP's question has been answered. Let's move along now.

--
Steven Otte, Model Railroader senior associate editor
sotte@kalmbach.com

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