6 axle vs 4 axle locos

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Rico

BN Modeller
Be careful what you clean your track with, some cleaners make things worse.
Do a search on track cleaning and you’ll get more opinions than most any other topic!
A good track cleaning car does indeed help.
 

GeeTee

Well-Known Member
Bachmann GP40s. They are identical. Do track cleaning cars work? People with larger layouts can’t be having these issues I would think
I have never found a track cleaning car that I was satisfied with ,some one else may have a different opinion.

What kind of track Nickel Silver ? Are you applying anything to it like oil cleaning solution ? Is the track inside a controlled environment ( AC )?.
 

Selector

Well-Known Member
There's a law of diminishing returns when we resort to steeper grades in our hobby. The steeper grade requires a longer vertical curve to ease into the grade from level and to ease back out of the grade at the top and to return to level. These vertical 'easements' eat up a ton of room, and force the grade between them to be both shorter and steeper than we had intended. A lose-lose proposition.
 

Greg@mnrr

Section Hand
There's a law of diminishing returns when we resort to steeper grades in our hobby. The steeper grade requires a longer vertical curve to ease into the grade from level and to ease back out of the grade at the top and to return to level. These vertical 'easements' eat up a ton of room, and force the grade between them to be both shorter and steeper than we had intended. A lose-lose proposition.
Sometimes by placing at grade on the outside (backside) of a layout the more real estate can be gained to lower the grade percentage. I have an Interchange above the layout in on section and the grade starts a slow ascend and travels something like 16 feet to achieve a workable grade. A tunnel is under the Interchange yard.

Greg
 
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tootnkumin

Well-Known Member
Staff member
You forgot (e) Pushers. 😊
Pushers can be problematic (unless using Ring enginerring Rail Pro, where speed matching is automatic and varies according to load) with speed matching so the pusher doesn't excert more push than needed and shoves cars off the track. An extra helper or two at the front can be easier to deal with where the weight in the train will balance out any minor discrepencies between them. Even mid train ones are better in that way too, but no more than at the front.
 

CambriaArea51

Well-Known Member
Pushers can be problematic (unless using Ring enginerring Rail Pro, where speed matching is automatic and varies according to load) with speed matching so the pusher doesn't excert more push than needed and shoves cars off the track. An extra helper or two at the front can be easier to deal with where the weight in the train will balance out any minor discrepencies between them. Even mid train ones are better in that way too, but no more than at the front.
That is where modeling skills come into play. Your rolling stock has to be tuned in so that they roll good and have no binding issues. A 4% grade is a little much but a 1.5-2% grade can be done. A steeper grade can be done but it would be maned helpers in that case.
 

Greg@mnrr

Section Hand
There no doubt that there some benefit to running with four extra wheels on a six axle locomotive. Those four extra wheels add traction to the locomotive and the extra weight is a help as well.

You could run several six axle locomotives in a consist to improve pulling power.

Greg
 
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gjslsffan

Active Member
Some great input and advise given here. Tractive effort varies greatly on locomotive models, depending on weight wheel make up, yes different profiles and materials make a difference . I have 4 axle units that would drag a 6 axle unit in a test. Models can be very finicky.
4% grades are gonna be a challenge. Just as info, the timetable I still have for the D&RGW/SP Minturn to Tennessee Pass (3.5% grade) a GP38 was good for only 460 tons, so with a loaded 130 ton car, means that a GP38 could pull 3 cars. A GP40 was good for maybe 5 loaded cars, MT cars weigh in around 30 tons, so you can do the math. SD40T-2's w PTC (positive traction control) were good for 1200 tons, an AC was good for 2100 tons (I think they are waaay over rated myself).
As for adding help,(pushers), you should not shove on the end with more than one powered unit. Adding swing (mid train) help is almost always better. The challenge comes as to where to cut the swing help in, they should be pulling as much as pushing. There are many other factors involved if you wanna go all nuts with the not shoving on hazmat on and on.
As always rule 1.0 applies, as it is your RR and what ever you want to do is OK, rule 1.1 reefer's all other issues to rule 1.0. I am trying to show you there is almost always a prototype to match a model. I knew a guy that had a model RR that used swing help on every train over 15 cars, just for a 4' shove, in HO scale. Hey, his RR right?
As for your track power issues. As has been said before, a lot of issues can come to play as well. Is your trackage mounted on solid roadbed, meaning not on movable risers, or not supported between joiners? Is your outfit operating on carpet, or outside? Do your locomotives have all wheel electrical pickup? Are all those connections working properly? I am not that much knowledgeable about N scale. But many of these principles cross scale lines.
I am not at all trying to run down Bachmann, I dont know what vintage your power is, some early N/HO scale Bachmann power can be a challenge as well.
 

RickVS

Member
Thanks for all of the good feedback. Sorry for the long post. I think for Christmas I'm going to treat myself to a couple 6 wheel locos to replace my 4 axles, but really just because it looks better and may help prevent stalling, not because I'm having problems getting up my grade. So some relevant points: 1) when I originally posted this post, I was under the impression that my 2 locos weren't pulling my train up my grade. Some experience later, I think the real problem is the frequently dirty rails and loco wheels. If everything is dirty the wheels may spin or the train will stall. If I clean everything with isopropyl alcohol then my locos do indeed pull my train up the 4% grade at slow and fast speeds (it's a 4% grade because it is just a small figure eight in my office using Bachmann E-Z track and their figure eight pier kit). 2) I like to run this 20 car train at very slow speeds that are quiet while I work in my home office during the day. Again, if everything is clean then the train can operate at very slow speeds. However after just a couple of days of running the locos they will eventually just stop, usually at the top of the grade, requiring more juice, and then even more juice. At this point if they are moving quickly they never stall but it's too loud to run while I work, so I have to clean everything every few days. I wasn't banking on this much maintenance when I bought this simple train set on Amazon for my office. 3) Why do both locos stall at the same time? I can see if one loco hits a dirty patch and loses electricity, but the second loco should still be spinning its wheels, right? Instead, it also is dead in the water. 4) Am I doing something wrong that I have to clean my tracks every few days to enable my locos to successfully go up my grade on low speed? I have a high MERV 5" filter for the home and very little dust in my AC controlled office environment. 5) I am thinking that if I got more powerful 6 axle locos I could get away with less frequent track cleaning. I'm thinking that in theory with 6 wheels there will be more of a likelihood that electrical contact is preserved when a piece of dirt is encountered on the tracks. Also with a more powerful loco it would push/drag the other loco over a dirty patch until it could reenergize on a cleaner portion of track. This was part of my thinking getting two locos, but it hasn't worked out that way. How much of this makes sense? Thanks.
 




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