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6 axle HO engines

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6 axle HO engines
Posted by ROBERT GLIDDEN on Friday, January 6, 2017 3:41 PM

Is there a modification that can be made to a 6 axle HO loco to  navigate 18" curves?

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Posted by MisterBeasley on Friday, January 6, 2017 4:11 PM

Which engine, and who built it?

I've got a P1K RSC-3 and a U-boat.  They've both got 6 axles and they handle my 18 inch curves just fine.

It takes an iron man to play with a toy iron horse. 

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Posted by ATSFGuy on Friday, January 6, 2017 4:15 PM

A photo would be helpful.

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Posted by RR_Mel on Friday, January 6, 2017 4:19 PM

I also have Proto, Athearn, Model Power and Atlas 6 axle locomotives and all handle 18” radius without any problems.
 
 
Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951
 
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Posted by ATSFGuy on Friday, January 6, 2017 5:39 PM

What do you think looks more impressive? 4 axle locomotives or 6 axle locomotives?

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Posted by richhotrain on Friday, January 6, 2017 5:43 PM

No argument from me except to say that I am surprised that you guys have no problems running 6-axle diesels on 18" radius curves.  I just find that hard to believe.

Rich

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Posted by 7j43k on Friday, January 6, 2017 6:01 PM

My old Hobbytown RSD-5 will handle 18" curves.  But I found that out back in 1960.  I don't have any curves below 48" curves right now, so I can't tell you about more recent locos.

I suppose one could wonder about running something like Kato's SD90/43'sMAC's.  But there's running and there's running.

 

The general topic of diesel minimum radius has been discussed previously, at least once:

http://cs.trains.com/mrr/f/88/t/10446.aspx

 

Ed

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Posted by RR_Mel on Friday, January 6, 2017 6:20 PM

I have Atlas #4 Custom Line Turnouts in my yard.  My test track is made up of several sections of S curves made with 18” Radius Atlas code 83 curved sections mounted to a 1” x  8” x 48”.  All of my SD 7s/40s locomotives will pass the 18” Radius test. 
 
 
Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951
 
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I'm beginning to realize that aging is not for wimps.
 
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Posted by Soo Line fan on Friday, January 6, 2017 7:08 PM

I have run the following for years with no problems:

P2K SD60s

Kato SD 40-2s

Kato SD 45s

Athearn F 45s

Athearn SD 40-2s

Atlas SD 35s

Atlas SD 24s

Its an old myth that SDs cannot run well on 18" radius. Once upon a time when brass was popular, it was true but plastic is much more forgiving.

Jim

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Posted by BRAKIE on Friday, January 6, 2017 7:24 PM

richhotrain

No argument from me except to say that I am surprised that you guys have no problems running 6-axle diesels on 18" radius curves.  I just find that hard to believe.

Rich

 

Rich,Nothing hard to believe about it since there is two types of six axle locomotives the short 6 wheel locomotives and the long 6 wheel locomotives the Short six will take a 18" radius while the long six wheels won't.

Examples SD9,SD24,SD35,RSD4/5,RSD12,no problems. The long 6 like SD50s,SD60,SD70,long modern GE units etc yes,there should be issues since these takes at least 22" or larger curves according to the manufacturers.

Athearn SD40-2 will go around a 18" curve but,it doesn't look pretty at all.Athearn 6 axle U Boats will also take 18" curves.

Larry

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Posted by SeeYou190 on Friday, January 6, 2017 8:39 PM

My hidden curves are 19" minimum, I test all locomotives on 18" sectional track to be sure they will work. I only have a few 6 axle locomotives. A pair of Athearn PA-1's and Trainmaster. I also have a Proto 2000 SD-7. All four of these handle 18" radiusn curves with no modifications or operational problems.

Living the dream.

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Posted by riogrande5761 on Friday, January 6, 2017 9:41 PM

Personally I wouldn't want to run my six axle loco's on curves that sharp, even if I could trick them around, they would look pretty nutty on such sharp curves.   Heck, I was running my SD45's on 28-inch KATO Uni-track curves and they looked pretty sharp.

And then there is also the issue of being coupled to cars - to avoid issues, you'd need to couple to something of roughly similar length since long rolling stock coupled to short rolling stock into very sharp curves could be a recipe for derailment.

As others noted, many six axle loco's in HO will opperate on 18 inch curves and require no modification.  

Rio Grande.  The Action Road  - Focus 1977-1983

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Posted by richhotrain on Saturday, January 7, 2017 4:27 AM

riogrande5761

As others noted, many six axle loco's in HO will opperate on 18 inch curves and require no modification.   

On a prior layout, I had 22" and 24' radius curves. I had a devil of a time with 6-axle diesels on those curves. I cannot imagine running 6-axle diesels on 18" radius curves.

I don't know why they even make 18" radius curves. A 36" diameter won't fit on a typical door, and a 4'x 8' sheet of plywood would accommodate 22" radius curves, so IMHO 22" radius curve ought to be the minimum, not 18".

Rich

Alton Junction

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Posted by BRAKIE on Saturday, January 7, 2017 8:12 AM

riogrande5761
Personally I wouldn't want to run my six axle loco's on curves that sharp, even if I could trick them around, they would look pretty nutty on such sharp curves. Heck, I was running my SD45's on 28-inch KATO Uni-track curves and they looked pretty sharp.

I agree..Those long sixes needs at least 32" curves. I won't even think of running a long six on my ISL due to the medium Peco switches I use. I use my three short sixes(Atlas Classic SD35s and a older Atlas/Kato RSD12) without issues.

Wasn't there a discussion on the old Atlas forum about some six axle locomotives wheels spacing being off so they could go around 18" curves?

Larry

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Summerset Ry.


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Posted by Anonymous on Saturday, January 7, 2017 8:22 AM

This discussion makes me smile!

In Europe, the "standard" minimum radius is 360mm, which is roughly 14.75". All Marklin or Trix locos are able to negotiate those curves, even the Big Boy, although I have to admit it looks rather silly.

We have a lot less space available for our hobby at this end of the Big Pond and one of the answers is sharp curves, which we try disguise as much as possible. Another answer is truck mounted couplers.

Undoubtedly, 6-axle locos can be made to run on tight curves, that´s not the issue. The limiting factors are a) looks, and b) coupler mounting.

Should you have sufficient space to accomodate curves with a radius of 32" and bigger, consider yourself one lucky guy!

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Posted by BRAKIE on Saturday, January 7, 2017 8:22 AM

richhotrain
I don't know why they even make 18" radius curves. A 36" diameter won't fit on a typical door, and a 4'x 8' sheet of plywood would accommodate 22" radius curves, so IMHO 22" radius curve ought to be the minimum, not 18". Rich

Rich,Easy if you stop and think about it.. A lot of folk think if they use 18" curves they can add more scenery along the edge of the layout plus there are still 4x8' layouts in planing books that calls for 18" curves.

With that said.. I agree 18" curves should go away.

Larry

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Summerset Ry.


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Posted by CGW121 on Saturday, January 7, 2017 8:34 AM

While I mainly model the CGW in the 50s I also have 5 SD40s. I have F units and some jeeps. Most of the curves are 22" or larger but there are a few short 18" One SD40  is Kato the other 4 are athearn, 2 new and 2 older. The kato runs everywhere fine. Of the Athearn one of the older and one of the newer work fine the other 2 do not. Usually they get run at the club.

                                     Mike

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Posted by riogrande5761 on Saturday, January 7, 2017 9:44 AM

richhotrain
I don't know why they even make 18" radius curves. A 36" diameter won't fit on a typical door, and a 4'x 8' sheet of plywood would accommodate 22" radius curves, so IMHO 22" radius curve ought to be the minimum, not 18".

Rich

Yes, a 4x8 sheet of plywood will accomodate 22-inch curves, the answer to your question about why 18-inch curves is because if you have a two track oval, they will fit within the 22 inch oval with plenty of room so that trains don't sideswipe each other.

The 18 and 22 -inch curves remain with us due to the old 4x8 standard size sheet of plywood makes it relatively easy for beginners to graduate from the rug to building a fairly simple table top layout with sectional track.

Rio Grande.  The Action Road  - Focus 1977-1983

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Posted by MisterBeasley on Saturday, January 7, 2017 9:44 AM

Like many modelers, I model the late Transition Era.  So, most of my engines are 4-axle geeps and F-units, and most of my rolling stock is 40-foot boxcars.

Yeah, they're not perfect, but 18-inch curves suit me just fine.

It takes an iron man to play with a toy iron horse. 

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Posted by riogrande5761 on Saturday, January 7, 2017 9:57 AM

Sir Madog

This discussion makes me smile!

In Europe, the "standard" minimum radius is 360mm, which is roughly 14.75". All Marklin or Trix locos are able to negotiate those curves, even the Big Boy, although I have to admit it looks rather silly.

We have a lot less space available for our hobby at this end of the Big Pond and one of the answers is sharp curves, which we try disguise as much as possible. Another answer is truck mounted couplers.

Undoubtedly, 6-axle locos can be made to run on tight curves, that´s not the issue. The limiting factors are a) looks, and b) coupler mounting.

Should you have sufficient space to accomodate curves with a radius of 32" and bigger, consider yourself one lucky guy!

Your post made me smile - and there is a good reason to immigrate to a place were there is wide open spaces and lots of room to accomodate those broad curves.  Big Smile

I've been across the pond some 6 times, including "good old Germany" 4 times, as an old German native used to call it, and one thing Americans notice are the small cars, expensive gasoline, narrow streets in the cities and small dwellings.  England is similar - my last two trips over were to the UK and most British folks have very little space and do modules and such.

To be fair, folks in America who have been hit by economic vagaries of the recession, like myself, have not had much space for trains.  I live in the Washington DC area where the cost of living is among the higher places in the nation and a daughter in college with associated expenses.  The most I could afford is a townhome with a small basement and the train room is only 10x18'.  That may be generous by European standards but on the small side by American.  I was able to fit in 32-inch minimum curves by designing a simple twice around the walls layout with a 11 storage tracks under the yard.  It seems so small.  I

Speaking of truck mounted couplers,can see why many go with N scale where there is really no change of every getting a large layout space.  Much of the rolling stock in N has truck mounted couplers.

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Posted by BRAKIE on Saturday, January 7, 2017 10:53 AM

riogrande5761
Speaking of truck mounted couplers,can see why many go with N scale where there is really no change of every getting a large layout space. Much of the rolling stock in N has truck mounted couplers.

Jim,The quality  N Scale cars has body mounted couplers this started IIRC around 2010. The majority scream loud enough and over those that wanted truck mounted couplers for their 9 3/4" curves.

I fully agree HO eats the space-even my 12' ISL is small. I know what can be done in 12 foot in  N..

Palm slap! I wish I sold my HO instead of my N. Oh well! No use crying over spilled milk.

 

Larry

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Posted by Lone Wolf and Santa Fe on Saturday, January 7, 2017 11:58 AM

ROBERT GLIDDEN

Is there a modification that can be made to a 6 axle HO loco to  navigate 18" curves?

 

I ran Athearn SD40-2s and F45s on 18” radius for several years without many problems but they don’t like complicated switching or S turns a lot.
The only modification you can make is to use the Kadee couplers with a longer shank like #26, #36 or #146. This helps some because it is usually the couplers which cause derailments on sharp corners.
Tunnel motors have too long of a wheel base and will not run on 18” track.

Modeling a fictional version of California set in the 1990s Lone Wolf and Santa Fe Railroad
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Posted by kasskaboose on Saturday, January 7, 2017 8:32 PM

Ah, the curve issue. I had a 22" one and broadened it after buying an SMD 45 to 30".  What a thing of beauty seeing that go around! 

Can the loco behind the six-axle loco cause the derailment on an 18" curve?  Does it matter whether it's another six or a four?

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Posted by BRAKIE on Sunday, January 8, 2017 3:30 AM

kasskaboose
Can the loco behind the six-axle loco cause the derailment on an 18" curve? Does it matter whether it's another six or a four?

On short sixes no issues..The long sixes will usually derail the car behind it. I doubt if a long six could derail a locomotive but,their pilot or snowplows may hit.

Larry

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Posted by superbe on Sunday, January 8, 2017 8:51 AM

The discussion about 18" curves has brought back memories of when I started my HO layout in2007. Prior to that I had "played with trains" as a child. When my son became of age we got the old trains out of storage and added new ones. These were the indestructible and virtually trouble free Lionel trains.    

We ran the trains on 3 sections of 4'X8' plywood. I had never seen or held an HO before so when I chose HO I'd thought I’d have a railroad empire. It came as a real shock when I learned that Lionel O-27 stood for diameter and HO-18" was a radius.

Anyway I'm happy with the HO particularly when it comes to the scenery part of the layout.

I too have trouble with 6 axel diesels on my inner 18" main, but I attribute my problems to less than perfect track. Some of my steamers don't like it either.

Bob 

 

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Posted by dinwitty on Sunday, January 8, 2017 2:42 PM
answering the original question, sideplay of the wheels allows operation over sharp curves. The trick would be to file in the center axle bearings on the trucks thinner for a wider sideplay, maybe deepen the axle holes. The only other trick is to make the center wheels blind, a steam engine trick. The other issue is to look for truck rotation binding preventing sharper turning.
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Posted by Soo Line fan on Sunday, January 8, 2017 3:55 PM

Per the couplers, using the Kaydee whisker coupler gives more side to side (lateral) movement due to the small built in spring. Also, a long shank whisker can be used to clear snow plows or allow longer cars to couple to the unit.

The real issue is uneven track work which six axles are not as tolerant of.

Jim

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Posted by riogrande5761 on Monday, January 9, 2017 8:13 AM

MisterBeasley

Like many modelers, I model the late Transition Era.  So, most of my engines are 4-axle geeps and F-units, and most of my rolling stock is 40-foot boxcars.

Yeah, they're not perfect, but 18-inch curves suit me just fine.

Late transition did include a lot of passenger service; which would have been pretty common during that time frame (85' long was the standard length most passenger cars back then.

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Posted by SeeYou190 on Friday, January 13, 2017 9:25 PM

As I said in my post, it is my hidden cures that are 19 inch. All visible curves are 26 inches or larger. To my eye everything looks fine on these curves. I also run 8 driver steam locomotives with no problems. Amazingly, my Bachamnn 2-8-8-4 glides through 19 inch curves as easily as an F-7. What a masterpiece of engineering that beast is. It does look silly though.

-Florida Kevin

Living the dream.

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Posted by Anonymous on Monday, January 16, 2017 10:41 AM

BRAKIE
I agree..Those long sixes needs at least 32" curves. I won't even think of running a long six on my ISL due to the medium Peco switches I use. I use my three short sixes(Atlas Classic SD35s and a older Atlas/Kato RSD12) without issues.

Larry,

The Peco Medium radius turnout has a radius of 36", Peco Short has a radius of 24".  Peco Long is 60".

http://www.peco-uk.com/prodtype.asp?strPageHistory=category&numSearchStartRecord=0&strParents=3309,3322&CAT_ID=3327&numRecordPosition=81

My club uses Peco Mediums in many places, and my SD9043Macs have no issues.

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