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Yard Track Spacing and Radius...

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Posted by 7j43k on Tuesday, August 10, 2021 10:27 AM

Lastspikemike

Here's a thought: if 2" track centres on tight radius curves can't work why does Atlas make sectional track in 22" and 24" radii?  I note the absence of 20" radius sectional curves but 15" and 18" are made.

Doesn't Kato make sectional curves in 2" increments? 

 

 

No.

 

 

Ed

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Posted by SeeYou190 on Tuesday, August 10, 2021 10:29 AM

Doughless
Anybody care to guess what this track spacing would scale down to in terms of inches on center? 

While traveling I remember seeing many signs that said something like No Room For Man In Between Train Cars in yards and industrial areas.

It looks like some of those places should have those signs.

Surprise

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Posted by 7j43k on Tuesday, August 10, 2021 10:38 AM

Doughless

Anybody care to guess what this track spacing would scale down to in terms of inches on center? 

Or the yard that has access down the middle?

 9,029 Coal Rail Photos - Free & Royalty-Free Stock Photos from Dreamstime

 

 

I'm not guessing.  I'm using that mathematics thing, again:

I can't tell the track spacing on the other two, but the one above is about 12' -6", or 1 3/4" in HO.  I guess they're not followers of Inch-and-a-half Mike.

 

The curves are clearly hugely wider than what we use, and I doubt there'd be a need to increase track centers if it were reproduced in HO.

 

If you're advocating such a spacing in HO, it does make sense if you don't feel the need to reach in and pick up or rerail a car.  

If I had the room, and I were building a staging yard, I would want 2 1/2" to 3", for easy finger clearance.  Most people, probably including me, would likely shrink that number for more tracks.  Remember, staging can include adding and removing cars.

 

I'll mention that, in the real world, I worked on a project that had a 3" clearance between train and (large) obstruction.  

 

Ed

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Posted by SeeYou190 on Tuesday, August 10, 2021 10:43 AM

Doughless
Do all the tracks in a yard even have the same center spacing?  

No.

I can tell you by actual physical measurement, the SEMINOLE GULF yard in Fort Myers, Florida has 4 tracks, and none of the track spacing is equal.

However, every track is perfetly straight. I like the curved yards much better. Mine will be built on a very broad arc.

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Posted by IDRick on Tuesday, August 10, 2021 11:14 AM

IDRick

Okay, will mock it up when have some benchwork up...  Thanks.

 

Since I am in the planning phase, I'm going to just go to a 2-1/2 inch track spacing throughout my HO switching layout.  My four axle diesels and 60 ft cars should not have any problems "interacting" with cars/locos on adjacent straight or curved track.  Much easier to plan with software using a common spacing and will fit easily on the planned benchwork.  Yard will only have five tracks and in the switching area, max of two through tracks plus sidings.

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Posted by Doughless on Tuesday, August 10, 2021 11:27 AM

7j43k

 

 
Doughless

Anybody care to guess what this track spacing would scale down to in terms of inches on center? 

Or the yard that has access down the middle?

 9,029 Coal Rail Photos - Free & Royalty-Free Stock Photos from Dreamstime

 

 

 

 

I'm not guessing.  I'm using that mathematics thing, again:

I can't tell the track spacing on the other two, but the one above is about 12' -6", or 1 3/4" in HO.  I guess they're not followers of Inch-and-a-half Mike.

 

The curves are clearly hugely wider than what we use, and I doubt there'd be a need to go smaller in HO.

 

If you're advocating such a spacing in HO, it does make sense if you don't feel the need to reach in and pick up or rerail a car.  

 

I'll mention that, in the real world, I worked on a project that had a 3" clearance between train and (large) obstruction.

 

Ed

 

Sorry, having implicit understanding of that math thing, I know that an answer is not mathematically precise once the inputs start with the word "about".  

Since the math thing only really finds a precise answer when all of the inputs are constant knowns, the only math that matters here is when you plug your guess into the formula that scales your guess down to an HO relevant guess.

Which is what I asked for.  Thanks.  BTW, I guessed the same 1.75 inches.

And I guessed it replicating the pics by using two pieces of track, two hopper cars, and not even a micrometer (thats a hobby tool?) but the little pink ruler my daughter used in 4th grade.     

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Posted by ATLANTIC CENTRAL on Tuesday, August 10, 2021 11:32 AM

Just to share related info in both threads........

I'm not going to argue, dispute, suggest or disagree with anything or anybody here. 

I'm just going to make three simple statements.

First, as orginally suggested by several/many so far, simple testing is always a good idea.

Second, the NMRA has always been very "generous", and thereby conservative in its recomendations for curved track centers. Yet they have always "danced around" the tangent track center issue with scale feet rather than a real life dimension.

Their 14 scale foot recommendation is 1.931"..........

Third, I have used 2" track centers for tangent track since I was introduced to this hobby. As explained earlier it is the defacto industry standard for bridges, crossovers, etc.

I have used 2" track centers on curves, maybe sometimes stretching them out to 2-1/8", ever since I started using 36" radius as my minimum.

I have tested this with locos as big as the Bachmann EM-1 passing 80' Bachmann and Branchline passenger cars with no issues and room to spare.

So for appearance, space and better track civil engineering (yes, I engineer the track location before I install it), I will stay with 2" (or cheat them up just that 1/8") track centers. The NMRA recommended 2-15/32" is just ugly and unnecessary at 36" radius and above.

DISCLAIMER - I don't own a UP BigBoy, brass plastic or diecast, and I have no plans to ever own one. So I think the EM-1 qualifies as a large enough test loco.

Sheldon 

    

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Posted by 7j43k on Tuesday, August 10, 2021 11:48 AM

ATLANTIC CENTRAL

 

DISCLAIMER - I don't own a UP BigBoy, brass plastic or diecast, and I have no plans to ever own one. So I think the EM-1 qualifies as a large enough test loco.

 

 

DISCLAIMER ON DISCLAIMER:

IF you might be running articulateds that don't swivel the "rear" engine, you do need to be careful about curve spacing where they run.

I mentioned the Big Boy earlier, that has a half inch overhang on a 37" curve.  And that's the theoretical (mathematics again at work, here).  YOUR model might be more.

But it's not just Big Boy's.  There are other big articulateds that come mighty close.

And, lest you think that the above comment only applies to those darn brass locos, I remind you that the Intermountain Cab Forward does not have a swivel "rear" engine.

Maybe someone will make another plastic non-swivel articulated someday.  Maybe.

 

 

Ed

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Posted by Doughless on Tuesday, August 10, 2021 12:10 PM

And, the NMRA standards are obviously smart guidelines from which to alter, if you want, based upon how you are going to run your layout.  If you are going to run it generically, that's fine, then calculating precision beyond the guidelines seems like a waste of time.

However, if you ask questions like...do I need to run 85 foot long cars an every yard track, or a big boy on every track?  If not, you can then cut down the spacing between tracks to something like my pics posted above...since it appears that CSX/NS will not be running 89 foot flat cars along side the coal hoppers.

Does spacing need to be the same for every track?  Obviously, the radius will be descending as you move inwards along a curved yard. 

So many variables, so few constants. 

 

 

- Douglas

MSM
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Posted by MSM on Tuesday, August 10, 2021 1:00 PM

[quote user="richhotrain"]

Well, here is my reply to the OP, verbatim, and it was the first reply to this thread.

It was a serious reply based upon my own experience.

After I posted that reply to the OP, my subsequent replies were in support of Crandell's and Ed's similar responses - - - test the trackwork to see if it creates clearance problems or not.

Rich

 

 
richhotrain

I don't have an absolute answer for you, but I can make some suggestions.

A minimum radius of 36" is great, especially on mainlines, but not really necessary for yards. What is more important on curves is the spacing between tracks, and 2" on center on curves is tight even though you are limiting your rolling stock to 40' and 50' freight cars. Spacing of 2 1/2" on center on curves is far better, at least in my experience.

Years ago, I got some good advice from my LHS guys about spacing of tracks on curves. They recommended that I buy a pair of 85' boxcars and test them on actual track to be sure. I wouldn't blindly rely on the advice of others unless they can say with certainty that 2" on center spacing for 36" radius tracks will work based upon their actual experience.

If this were my layout, I would use 2 1/2" spacing on curves and, since it is the yard, I would step down the radius on curved tracks to something like 32" radius. In fact, that is exactly what I did on my old layout where I installed a yard on a curve on my layout.

Hope this helps.

Rich 

 

 
Gentleman,
 
As I’ve been following this thread, I realized that my track plan was not only inaccurate, but that I jumped the gun in posting it, my bad.  I apologize not only for not participating in this thread (don’t have the knowledge) and by for not mentationing that I intend to run large articulated locomotives.

I did some trial and error as suggested with the equipment I have and incorporated a lot of the suggestions that were made.  With that being said, I made the following adjustments:

 ·        Main line radius minimum 42”

 ·        Yard radius minimum 36” except for car shop where I’m using  28” - 32” curved turnouts

 ·        Main line track spacing is 2 ½

 ·        Yard and arrival / depart tangent spacing is now 2 ¼

 ·        West end of the yard, arrival / departure tracks are now spaced 2 ½ with easements

 ·        Inner arrival / departure track was extended about 30” from end curve to turnout

 ·        Yard ladders and other select turnouts were rearranged to accommodate “Caboose” ground throws

Last concern I have is do I need to space my yard turns (Freight Yard - 5 Tracks) at 2 1/2 or would 2 1/4 work considering 40' - 65' freight car lengths?

If anyone happens to notice anything else that might be a concern, I’d appreciate a comment or so…

Thanks

MSM

 

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Posted by IDRick on Tuesday, August 10, 2021 1:10 PM

ATLANTIC CENTRAL

Third, I have used 2' track centers for tangent track since I was introduced to this hobby. As explained earlier it is the defacto industry standard for bridges, crossovers, etc.

I have used 2" track centers on curves, maybe sometimes stretching them out to 2-1/8", ever since I started using 36" radius as my minimum.

I have tested this with locos as big as the Bachmann EM-1 passing 80' Bachmann and Branchline passenger cars with no issues and room to spare.

So for appearance, space and better track civil engineering (yes, I engineer the track location before I install it), I will stay with 2" (or cheat them up just that 1/8") track centers. The NMRA recommended 2-15/32" is just ugly and unnecessary at 36" radius and above.

Sheldon 

 

 
Sheldon, what spacing would you recommend for two parallel tracks (HO) with a minimum radius of 24 inches?  While I like your standard of 36" or greater curves, l just can't fit them into my switching shelf layout...  4 axle diesels, 60 foot cars, 18" shelves
 
 
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Posted by ATLANTIC CENTRAL on Tuesday, August 10, 2021 2:05 PM

IDRick

 

 
ATLANTIC CENTRAL

Third, I have used 2' track centers for tangent track since I was introduced to this hobby. As explained earlier it is the defacto industry standard for bridges, crossovers, etc.

I have used 2" track centers on curves, maybe sometimes stretching them out to 2-1/8", ever since I started using 36" radius as my minimum.

I have tested this with locos as big as the Bachmann EM-1 passing 80' Bachmann and Branchline passenger cars with no issues and room to spare.

So for appearance, space and better track civil engineering (yes, I engineer the track location before I install it), I will stay with 2" (or cheat them up just that 1/8") track centers. The NMRA recommended 2-15/32" is just ugly and unnecessary at 36" radius and above.

Sheldon 

 

 

 
Sheldon, what spacing would you recommend for two parallel tracks (HO) with a minimum radius of 24 inches?  While I like your standard of 36" or greater curves, l just can't fit them into my switching shelf layout...  4 axle diesels, 60 foot cars, 18" shelves
 
 
 

As mentioned, testing is good. But 24" radius will likely require at least 2-3/8", possibly more. And that assumes the equipment choices you mentioned.

Sheldon

    

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Posted by Pruitt on Tuesday, August 10, 2021 2:06 PM

MSM
Gentleman,
 
As I’ve been following this thread, I realized that my track plan was not only inaccurate, but that I jumped the gun in posting it, my bad.  I apologize not only for not participating in this thread (don’t have the knowledge) and by for not mentationing that I intend to run large articulated locomotives.

I did some trial and error as suggested with the equipment I have and incorporated a lot of the suggestions that were made.  With that being said, I made the following adjustments:

 ·        Main line radius minimum 42”

 ·        Yard radius minimum 36” except for car shop where I’m using  28” - 32” curved turnouts

 ·        Main line track spacing is 2 ½

 ·        Yard and arrival / depart tangent spacing is now 2 ¼

 ·        West end of the yard, arrival / departure tracks are now spaced 2 ½ with easements

 ·        Inner arrival / departure track was extended about 30” from end curve to turnout

 ·        Yard ladders and other select turnouts were rearranged to accommodate “Caboose” ground throws

Last concern I have is do I need to space my yard turns (Freight Yard - 5 Tracks) at 2 1/2 or would 2 1/4 work considering 40' - 65' freight car lengths?

If anyone happens to notice anything else that might be a concern, I’d appreciate a comment or so…

Thanks

MSM

MSM,
 
Based on my experience with a 36 inch minimum radius, 2" centers work fine even with 80' cars, so your relatively conservative (pardon that word) 2 1/4 to 2 1/2 inch centers should work great. It will give you ample clearance between cars on adjacent tracks, and will also provide finger space whenever you need to reach in for some reason. 
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Posted by SeeYou190 on Tuesday, August 10, 2021 2:07 PM

IDRick
I'm going to just go to a 2-1/2 inch track spacing throughout my HO switching layout. 

I like 2 1/2 inch spacing. I can get my fingers in there.

That is something the prototype does not take into consideration.

IDRick
  While I like your standard of 36" or greater curves, l just can't fit them into my switching shelf layout..

I cannot fit them in either.

Doughless
not even a micrometer (thats a hobby tool?)

Yes it is. I have two in my hobby box, and eight more in the big tool box in the garage.

I strongly believe in always using the best tool for the job.

Lastspikemike
You were supposed to look this up.

Gee Ed, the hall monitor called you out for not doing your homework!

Huh?

-Kevin

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Posted by ATLANTIC CENTRAL on Tuesday, August 10, 2021 2:18 PM

One more random thought, as it applies to ME, For my modeling style.

I try to avoid handling equipment other than steady it from the top when manually uncoupling.

I'm not an "active fiddle yard" kind of guy, I don't store much excess rolling stock off the layout.

That's why the new layout is designed to store 1,000 freight cars and 150 passenger cars.

Picking them up randomly in a freight yard or staging yard is just not an issue for me.

The whole layout is designed around 2" track centers.

Sheldon

    

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Posted by SeeYou190 on Tuesday, August 10, 2021 2:21 PM

ATLANTIC CENTRAL
I try to avoid handling equipment

I made a decision to include a carfloat on the new layout, and it will be "fiddled" in between play sessions.

I think I will also install an interchange track to be fiddled as well.

I overbuilt the Fleet Of Nonsense in the past four years by about 40 freight cars, and I still have more to build.

-Kevin

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Posted by Doughless on Tuesday, August 10, 2021 2:31 PM

Lastspikemike

 

 
7j43k

 

 
Lastspikemike

Here's a thought: if 2" track centres on tight radius curves can't work why does Atlas make sectional track in 22" and 24" radii?  I note the absence of 20" radius sectional curves but 15" and 18" are made.

Doesn't Kato make sectional curves in 2" increments? 

 

 

 

 

No.

 

 

Ed

 

 

 

You were supposed to look this up.

Kato HO curved sectional track is made in 2 3/8" radius increments, somewhat wider (by 3/16") than the Mark V NMRA gauge size. 

If it works for Kato and for Atlas.....?

 

Mike, as you are learning in this hobby, manufacturers make products that are incomplete.  The product can do some things, but fails at other things.  When judged with the standard that each product should do what the other guy's does, they all fall short of being competent because they were designed to only do limited applications.

The Atlas sectional track was designed, mainly, to provide train set type of 4 x 8 layouts way back in the day.  Their trackplan book has many plans with 22 inch radius curves inside a 24.  But those train set plans would not work if the buyer was running 85 foot passenger cars (which Atlas doesn't make BTW, AFAIK).  Atlas doesn't disclose that part. 

Producers don't disclose in what situations their product fails. For one reason, the list would be way too long.

We have to figure it out for ourselves. 

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Posted by ATLANTIC CENTRAL on Tuesday, August 10, 2021 2:36 PM

7j43k

 

 
ATLANTIC CENTRAL

 

DISCLAIMER - I don't own a UP BigBoy, brass plastic or diecast, and I have no plans to ever own one. So I think the EM-1 qualifies as a large enough test loco.

 

 

 

 

DISCLAIMER ON DISCLAIMER:

IF you might be running articulateds that don't swivel the "rear" engine, you do need to be careful about curve spacing where they run.

I mentioned the Big Boy earlier, that has a half inch overhang on a 37" curve.  And that's the theoretical (mathematics again at work, here).  YOUR model might be more.

But it's not just Big Boy's.  There are other big articulateds that come mighty close.

And, lest you think that the above comment only applies to those darn brass locos, I remind you that the Intermountain Cab Forward does not have a swivel "rear" engine.

Maybe someone will make another plastic non-swivel articulated someday.  Maybe.

 

 

Ed

 

I understand and agree, but I like the double swivel articulated locos, as I said earlier, they make our large (but still compressed) curves look larger. 8 of my 11 articulated locos are x-6-6-x designs anyway.

And, I don't see a long list of additional articulated locos in my future, brass or plastic.

I actually limit the rigid wheelbase of steam that I purchase to 21 scale feet, so the are no 4-12-2's on my shopping list either, or even any 2-10-4's for that matter.

Largest rigid wheelbase locos I have, USRA light 2-10-2's with 57" drivers.

These standards were imposed for appearance and operational reliability at the chosen minimum radius.

Sheldon

    

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Posted by Doughless on Tuesday, August 10, 2021 2:36 PM

SeeYou190
Doughless not even a micrometer (thats a hobby tool?) Yes it is. I have two in my hobby box, and eight more in the big tool box in the garage. I strongly believe in always using the best tool for the job.

I don't disagree with using the best tool for the job. 

I'm asking what are the jobs in model railroading where you need that level of precision? 

Boring out a cylinder, I get.  Laying track, or placing a trackside building, I'm lost.

That's not a challenge to your methods, its just that the discussions on the forums seemingly involve an ever more level of precision that I've never considered. and I'm wondering what I've been missing or doing wrong all of these years. 

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Posted by selector on Tuesday, August 10, 2021 3:16 PM

IDRick

Okay, will mock it up when have some benchwork up...  Thanks.

 

 

At which, we all close our eyes, smile, and emit a resounding, "AAAaaaahhh...!", like Bill Shatner as the MC in the talent show in that movie when the main character looks wide-eyed and then hastily adds, "...and world peace."

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Posted by IDRick on Tuesday, August 10, 2021 3:26 PM

selector

 

 
IDRick

Okay, will mock it up when have some benchwork up...  Thanks.

 

At which, we all close our eyes, smile, and emit a resounding, "AAAaaaahhh...!", like Bill Shatner as the MC in the talent show in that movie when the main character looks wide-eyed and then hastily adds, "...and world peace."

 

? Very strange response...  whatever  Sometimes replies are helpful and others not so much...

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Posted by ATLANTIC CENTRAL on Tuesday, August 10, 2021 4:37 PM

Doughless

 

 
SeeYou190
Doughless not even a micrometer (thats a hobby tool?) Yes it is. I have two in my hobby box, and eight more in the big tool box in the garage. I strongly believe in always using the best tool for the job.

 

I don't disagree with using the best tool for the job. 

I'm asking what are the jobs in model railroading where you need that level of precision? 

Boring out a cylinder, I get.  Laying track, or placing a trackside building, I'm lost.

That's not a challenge to your methods, its just that the discussions on the forums seemingly involve an ever more level of precision that I've never considered. and I'm wondering what I've been missing or doing wrong all of these years. 

 

You are likely not doing anything wrong, but you may not be involved in some aspects of the hobby that others are. I use my micrometer a fair amount.

But I kit bash locomotives, measure axle lengths for proper replacement fit, build the occasional custom turnout, etc.

But I'm the same guy that layed my straight track with a 36" steel rule, then checked it with a lazer...... we use them to install kitchen cabinets, why not use them to lay track?

Sheldon

    

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Posted by 7j43k on Tuesday, August 10, 2021 4:52 PM

Doughless

But those train set plans would not work if the buyer was running 85 foot passenger cars (which Atlas doesn't make BTW, AFAIK). 

 

They sell the old Branchline cars.  The sleepers are all 85'.

 

Ed

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Posted by 7j43k on Tuesday, August 10, 2021 5:02 PM

Doughless
That's not a challenge to your methods, its just that the discussions on the forums seemingly involve an ever more level of precision that I've never considered. and I'm wondering what I've been missing or doing wrong all of these years. 
 

If you get satisfactory results with your methods, you are not doing anything wrong.

If you see discussions that involve more precision than you care about, so what?  That's what THEY want to discuss.  I don't see why it would bother you if they do.  Just move on to a different topic.

 

Ed

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Posted by Doughless on Tuesday, August 10, 2021 5:09 PM

ATLANTIC CENTRAL

 

 
Doughless

 

 
SeeYou190
Doughless not even a micrometer (thats a hobby tool?) Yes it is. I have two in my hobby box, and eight more in the big tool box in the garage. I strongly believe in always using the best tool for the job.

 

I don't disagree with using the best tool for the job. 

I'm asking what are the jobs in model railroading where you need that level of precision? 

Boring out a cylinder, I get.  Laying track, or placing a trackside building, I'm lost.

That's not a challenge to your methods, its just that the discussions on the forums seemingly involve an ever more level of precision that I've never considered. and I'm wondering what I've been missing or doing wrong all of these years. 

 

 

 

You are likely not doing anything wrong, but you may not be involved in some aspects of the hobby that others are. I use my micrometer a fair amount.

But I kit bash locomotives, measure axle lengths for proper replacement fit, build the occasional custom turnout, etc.

But I'm the same guy that layed my straight track with a 36" steel rule, then checked it with a lazer...... we use them to install kitchen cabinets, why not use them to lay track?

Sheldon

 

I no longer build models, which is where precision that's measured in fractions of inches comes mainly into play.  The guys who ran the CAD program at Athearn that eventually popped out a styrene boxcar and installed all of its specific details did all of that precise work for me, so to speak.  And before that, Irv Athearn molded his BB stuff just fine, with only a little weathering needed.

We can't build structures to scale, they'd be huge.  We can't lay curves to scale, they'd eat up the room.  I'm baffled by all of the conversations about fractions of inches and how it makes a difference in realism when we are challenged by so many other things we can't change. 

 

You've mentioned a few areas, but most here asking questions are not going to rebuild their trucks or build a custom turnouts.  

Threads wander.  It seems like lately they wander down the path of precision just for the sake of it.

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Posted by 7j43k on Tuesday, August 10, 2021 5:12 PM

Doughless

Sorry, having implicit understanding of that math thing, I know that an answer is not mathematically precise once the inputs start with the word "about".  

Since the math thing only really finds a precise answer when all of the inputs are constant knowns, the only math that matters here is when you plug your guess into the formula that scales your guess down to an HO relevant guess.

Which is what I asked for.  Thanks.  BTW, I guessed the same 1.75 inches.

And I guessed it replicating the pics by using two pieces of track, two hopper cars, and not even a micrometer (thats a hobby tool?) but the little pink ruler my daughter used in 4th grade.     

 

 

I certainly wasn't going after precision.  Oddly, mathematical tools work on both precise and imprecise dimensions.  

I know the typical width of a freight car is 1 1/2" (about) in HO.  So I simply scaled the width of the car and the width of the open space between the cars, set up a proportion, and solved for x (x being the HO distance between the cars).  Adding 1 1/2 and 1/4, I got my answer.

As I said, I wasn't guessing.  And neither did you, if you built a sufficiently accurate model to measure.

 

Ed

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Posted by 7j43k on Tuesday, August 10, 2021 5:15 PM

Doughless

Threads wander.  It seems like lately they wander down the path of precision just for the sake of it.

 

Other people's interest in precision seems to be really bothering you.  Again, if a topic is becoming of no interest to you, why not just drop it, and leave it for the people who DO have an interest?

 

Ed

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Posted by SeeYou190 on Tuesday, August 10, 2021 5:26 PM

Doughless
SeeYou190
Doughless not even a micrometer (thats a hobby tool?) Yes it is. I have two in my hobby box, and eight more in the big tool box in the garage. I strongly believe in always using the best tool for the job.

I don't disagree with using the best tool for the job. 

I'm asking what are the jobs in model railroading where you need that level of precision? 

Doug, sorry my intention was lost in the wording. I meant my response about using my professional set of precision micrometers in model building as a bit toungue-in-cheek.

In reality, for model building, all the precision I will ever need can be achieved with this 6" Mitutoyo dial caliper, and nothing more.

-Kevin

Living the dream.

  • Member since
    February 2015
  • From: Ludington, MI
  • 1,862 posts
Posted by Water Level Route on Tuesday, August 10, 2021 6:02 PM

Doughless

 

 
Lastspikemike

 

 
7j43k

 

 
Lastspikemike

Here's a thought: if 2" track centres on tight radius curves can't work why does Atlas make sectional track in 22" and 24" radii?  I note the absence of 20" radius sectional curves but 15" and 18" are made.

Doesn't Kato make sectional curves in 2" increments? 

 

 

 

 

No.

 

 

Ed

 

 

 

You were supposed to look this up.

Kato HO curved sectional track is made in 2 3/8" radius increments, somewhat wider (by 3/16") than the Mark V NMRA gauge size. 

If it works for Kato and for Atlas.....?

 

 

 

Mike, as you are learning in this hobby, manufacturers make products that are incomplete.  The product can do some things, but fails at other things.  When judged with the standard that each product should do what the other guy's does, they all fall short of being competent because they were designed to only do limited applications.

The Atlas sectional track was designed, mainly, to provide train set type of 4 x 8 layouts way back in the day.  Their trackplan book has many plans with 22 inch radius curves inside a 24.  But those train set plans would not work if the buyer was running 85 foot passenger cars (which Atlas doesn't make BTW, AFAIK).  Atlas doesn't disclose that part. 

Producers don't disclose in what situations their product fails. For one reason, the list would be way too long.

We have to figure it out for ourselves. 

 

I would take this a bit further to say that 22" radius sectional track is made as it makes a 180 curve that fits nicely on the 'ol 4x8 sheet of plywood.  24" radius seems to be a not uncommon minimum radius on manufactured equipment and was the old "standard" radius curve according to John Armstrong (among others, I'm sure).  Seems like logical reasons to offer them both.  Not necessarily that they are meant to be used next to each other.  For example, Atlas also makes a #8 turnout and a "snap-switch" that are not intended to be used together to build a crossover.  Yet there they both are for sale under the Atlas banner.  15" and 18" were old standards.  20" lacked enough reason to exist.

If it was so great why would Kato go a different route in our copycat hobby?

As for Atlas track plans showing tight curves paired up, I've not looked at an Atlas book in many moons, but I seem to recall seeing this before.  However, I also recall seeing that the center points of the curves were not the same.  The outer track didn't start curving until after the inner had started so they did not have a 2" spacing in the curve.  If their tangent centerlines were greater than 2" already, it would make this a necessity to still allow their sectional track to work in the plan.

Mike

  • Member since
    December 2008
  • From: Heart of Georgia
  • 5,406 posts
Posted by Doughless on Tuesday, August 10, 2021 7:10 PM

7j43k

 

 
Doughless

Threads wander.  It seems like lately they wander down the path of precision just for the sake of it.

 

 

 

Other people's interest in precision seems to be really bothering you.  Again, if a topic is becoming of no interest to you, why not just drop it, and leave it for the people who DO have an interest?

 

Ed

 

Because the topic isn't really about precision.  That's the topic after hijack. The topic was answered by suggesting live iterations should be how spacing is determined.  Whether or not OP even bothers to measure the precise distance beyond the eyeball distance the hands on iterations provided is rather inconsequential to the goal.

But I suppose measurements could provide a supporting role, so he doesn't have to perform an iteration for each track.....provided of course that the radius doesn't change as he moves inward...DOH!

 Maybe he could just add about an 1/8 of an inch to each center line as he moves inward, determined by your pink plastic ruler of course, and call it problem solved.

- Douglas

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