I have a Riverossi 4-6-4 Hudson which has traction tires and it pulls like the devil up 3% slopes. I have Bachmann 2-8-8-4 EM-1 engine that is either straining or slipping when pulling the same freight at the same speed up a 3% slope. The EM-1 will absolutely pull the freight up the grade with some more throttle, but it slows without doing this while the Riverossi does not. I have not looked real close to see if the EM-1 has traction tires, but I do not think it does.
I have the ability to put traction tires on the EM-1 with Bull Frog Snot, but my question is:
Are engines designed to slip at a certain load point to protect the motor from overload, or do they just slip due to low weight or poor traction. I really think that adding traction tires to the EM-1 will enhance it's pulling ability, but don't want to overload it at the same time.
Previous discussions of "BFS vs. Traction Tires" leads to some interesting opinions and experience.
I have added BFS to one drive wheel on my older models, mostly as an experiment. I have doubled the pulling capacity of those old locos using this stuff.
On newer models, like your EM-1, I prefer to add weight, perhaps an ounce, maybe two. I have no expertise in this, but the added weight does increase pulling power, and still allows the wheels to 'slip' if the locomotive is overloaded.
A word of caution: The EM-1 has more moving parts in order to drive two 8-wheeled trucks. More things can go wrong by overloading the drive train. My humble opinion is to not add traction or weight to this locomotive, to ensure it runs for a very long time. This locomotive is mechanically complicated.
Some folks really like traction tires. I feel like it's one more part that will need to be replaced over time. I'd rather pull fewer cars, or better yet, get two EM-1s, and double head 'em. My rule is to restrict the EM-1 to no more than a 20-car train, with gentle grades. 3% is a bit too steep with long trains.
Regards,
Jonathan
as a general rule, i avoid locomotives with traction tires like the plague. most that come with them are poor quality train set locomotives from years gone by. traction tires also cut down on the number of wheels which pick up electricity from the track. they also cause the wheels to be out of round. in my experience, a locomotive with traction tires (diesel) will bounce itself off the track once the wheels slip.
the best solution for pulling grades is to either cut down train length, or double head the locomotives.
i thought the only 3% grade you had was coming up from your turntable, and only used by light engines?
Quote from: rbryce1 on October 10, 2012, 08:59:30 AM
I have a Riverossi 4-6-4 Hudson which has traction tires and it pulls like the devil up 3% slopes. I have Bachmann 2-8-8-4 EM-1 engine that is either straining or slipping when pulling the same freight at the same speed up a 3% slope. The EM-1 will absolutely pull the freight up the grade with some more throttle, but it slows without doing this while the Riverossi does not. I have not looked real close to see if the EM-1 has traction tires, but I do not think it does.
I have the ability to put traction tires on the EM-1 with Bull Frog Snot, but my question is:
Are engines designed to slip at a certain load point to protect the motor from overload, or do they just slip due to low weight or poor traction. I really think that adding traction tires to the EM-1 will enhance it's pulling ability, but don't want to overload it at the same time.
drivers slipping is the safety valve for saving your motors. I can't speak for steam but I have used BFS on several diesels where I couldn't add weight. I too prefer the weight vs. traction tires. BFS did increase the TE. My next test will be on a Bachmann SF Northern. Phil
The real test as to motor safety is to check the amp draw of the motor. In ancient, open frame motor times the usual rating for something like a DC-70 motor was 1 amp. If your model began slipping as it reached that rating, it was OK. The rating for today's high efficiency motors is much less than 1 amp, and in most cases the data sheets that come with the models don't give that info. I wouldn't be overly agressive in adding weight to today's models. In the case of the EM-1, some additional weight would likely help, but it should be distributed evenly so that both engines get some of the weight. How and where to add the weight will depend on what space is available within the boiler or maybe between th frames.
Quote from: jward on October 10, 2012, 11:30:01 AM
I thought the only 3% grade you had was coming up from your turntable, and only used by light engines?
Jeff,
You have a pretty good memory!! My permanent layout will only have a max 3% grade for just engines, but that one is still on the drawing boards. This one is our smaller (4'-6" x 12') double dog-leg (sort of like a long "W" without the middle "V") Christmas layout which is under construction right now.
It has 3 tracks (none of which are interconnected) with 3 trestles to cross over a stream leading to a pond. There is a seashore with a light house to the right, a residential district in the center and a recreational park with a pond and a car show on the left. The scenery on the left is Autumn scenery and it gradually turns to Winter in the middle and on the right for the Christmas scenery. All the tracks on the rear wall are elevated, one is 2" overall rise, the middle is 1.5" and the inner is 1" in total rise. The outer rail will have the Alaska McKinley Explorer running on it, the center will have a freight train with the 4-6-4 Hudson and the center or residential rail section will have the Bachmann "San Fransisco Cable Car" is recently successfully installed a decoder in for DCC operation.
The permanent layout will be constructed in the room where we are currently building the smaller portable Christmas layout, which will be moved to the living room next month. After Christmas, it will be disassembled and stored till the next year. It is constructed totally on a large sheet of 3" composite aluminum-foam wall panel, like the kind used for the walls and roof on Sunrooms. Tons of strength (you can walk on it) and light as a feather (I can carry it myself, but far to bulky for just one person).
At any rate, I just bought the EM-1 at the train show a few weeks ago and tried to see how well it compared with the other engines on the Christmas layout, and that was what I had found.
Actually, on the permanent layout, the EM-1 will be pulling about 9-10 freight cars and only be on the Mountain rail section, of which the max slope is a 2.0 slope with 28" R turns and a total of a 3" rise. The second train on that rail will be the Alaska McKinley Explorer with 5 McKinley cars and 2-3 Alaska diesels. This way I can fit an entire train on a siding loop. The EM-1 will not see the turn table, as it is far too long to fit on it anyway.
I agree with jward and Johnathon and others.
Either add weight or double head or reduce the length of the train(s). However, do not add so much weight that your wheels will not slip under full load. Spinning wheels are a safety valve.
I can't speak for BFS but it's probably the same a traction tires. Wheel spin will save your motor, see above. Traction tires and probably BFS do not let the wheels spin and you can burn out a motor. Very expensive, just for the sake of a few extra cars.
For me, no traction tires and, until I experiment, no BFS. I'd rather add weight, especially to my steam, which I do as a matter of course anyway, or double head, which is more prototypical or reduce train length(s), again, prototypical. You could even prototypically double the hill.
Of course, the obvious solution when designing the model railroad is not to have grades over 2% in the first place.
Quote from: rbryce1 on October 10, 2012, 08:59:30 AM
I have the ability to put traction tires on the EM-1 with Bull Frog Snot, but my question is:
rb-
You don't use BFS to add traction tires. It's a coating for (usually) one set of drivers. Actual traction tires are rather like a rubber band which is a little smaller than the circumference of your wheel. The "tire" rests in a groove in the metal wheel.
Allow me to second the advice about being careful with BFS and traction tires. You can burn out a motor or a PCB if your wheels can't spin.
-- D
I was not going to put the BFS on the traction tires! The EM-1 does not come with traction tires.
I am aware of what a real traction tire is and why they are there, as my Riverossi 4-6-4 Hudson has them. I also see what the 4-6-4 does without them. BFS is an alternate to using the actual tire should yours begin to fall off like mine did on my Riverossi and you can't find a replacement. I found and purchased the BFS in the event I needed to use it as a replacement for the correct traction tire, then a day or so later found and bought the correct traction tire. Still have not bought the tool I need to install the actual traction tires on the Riverossi and I don't feel like using pliers and screwing up the head of the microscopic bolts on the engine wheels.
My main concern is whether adding the BFS to the EM-1 may overload the EM-1 by having the wheels grip rather than spin at the point where the wheels spinning are protecting the motor from overload, or if the wheels are simply spinning. Kind of like having a race car that has enough power to spin the rear wheels and it's drive train can handle it, so you go to larger tires which allow you to use the power you were losing by the wheels spinning. At some point, you reach the condition where the tires are so large they no longer spin at all under any condition, and if you continue to push it, the gears now break. Don't know if the EM-1 is already designed at that point or it can take more traction without problems.
Kind of like to hear from the Bachmann on this as well.
Do DCC decoders have current limiters for protecting the motor? If so, that should protect the motor.
Quote from: MAGER on October 15, 2012, 01:15:35 PM
Do DCC decoders have current limiters for protecting the motor? If so, that should protect the motor.
Actually, and I'm sure I'm going to be corrected if I am wrong, I think it goes the opposite way. You need to buy a decoder with a higher rating than the stall speed current of your engines motor.
If you apply full power to your engine while holding in in place with just enough pressure to stop the wheels from turning, and read the current being drawn at that time, that is the stall speed current draw. You need a decoder with a higher current rating than the stall speed current or you may burn up the decoded.
Don't think there is any protection the other way.
Sounds to Bachmann like you are pushing it up too steep a grade.....
Quote from: rbryce1 on October 15, 2012, 01:27:09 PM
Quote from: MAGER on October 15, 2012, 01:15:35 PM
Do DCC decoders have current limiters for protecting the motor? If so, that should protect the motor.
Actually, and I'm sure I'm going to be corrected if I am wrong, I think it goes the opposite way. You need to buy a decoder with a higher rating than the stall speed current of your engines motor.
If you apply full power to your engine while holding in in place with just enough pressure to stop the wheels from turning, and read the current being drawn at that time, that is the stall speed current draw. You need a decoder with a higher current rating than the stall speed current or you may burn up the decoded.
Don't think there is any protection the other way.
Some decoders like the Tsunami have over temp protection, I know the Tsunami do but I would never depend on that. Then the fuse on the decoder opens. Send the decoder back for repair.
Measure the motor current carefully is about the only way to be somewhat safe. A multimeter for DC and a DCC amp meter, RRampMeter, for DCC layouts.
Rich
Quote from: Yardmaster on October 15, 2012, 02:32:19 PM
Sounds to Bachmann like you are pushing it up too steep a grade.....
Bachmann,
3% grade. Again, only the EM-1 is having the problem. Please review my 1st post in this thread for the specifics. Is 3% too much for the EM-1?
Like I said - too steep...
Also - how clean is the track?
Quote from: Yardmaster on October 15, 2012, 03:10:11 PM
Like I said - too steep...
Also - how clean is the track?
Track is very clean NS rail. I use the Bachmann track cleaning tank car.
Yours is the only complaint we have heard about the tractive effort of the EM1. Not really sure what your problem could be other than too steep of a grade.
What I will try is, Thursday evenings, there is another member of out Model Railroad Club who has (2) EM1's he uses in a consist to pull 5 X10 to the third power of freight cars, mostly flat track but we do have a 2% slope at one point. I will take it over an compare the traction on his engines (separately of course) with mine and see the results. If mine pulls the same as his, that's what it is. If not, we can look farther.
I will admit, when the Riverossi had it's traction tires it pulled like crazy. When it started throwing it's tires and I removed all of them to stop it from wobbling, it could hardly pull itself around.
QuoteTrack is very clean NS rail. I use the Bachmann track cleaning tank car.
If all you are using is the track cleaning car your track is not as clean as you think.
It does take a little elbow grease to clean the tracks.
Jerry
The track is definitely clean. I vacuum it, wipe it down and run the cleaning car over it. I have 14 engines now, both steam and diesel. None of the 14 engines even stutter, and all are DCC. The engine does not run the slightest bit jerky or loose power anywhere.
The oldest piece of track I own is 4 months old. It is all Nickel Silver. If 13 engines, including a 5" switcher, a 4" cable car with a single powered truck and (2) 0-4-0 steam engines run perfectly, I really don't believe that dirty track is the problem. It is something else. It may, in fact, be dirty wheels. I do not have any good wheel cleaning devices yet, but I know I need to get some.
I am also not suggesting there is a design problem with the EM1 either. It's reported to be Bachmann's best, and I believe it. This Thursday I will do a comparison test with 2 other EM1's over at the club. If mine does not pull as well as theirs, I have a direction to look. If it does, ? All I know is right now, it is being out pulled by my Riverossi 4-6-4 Hudson which is about 15 years old, was originally a DC engine and I installed a decoder in it, and that just isn't right!
have you removed the packing foam from the rear wheels i had trouble with one of my steams that couldnt pull much up a grade one day it derailed and i saw the foam and it fixed the promblem. sometimes something so easy can be frustrating dave
rbryce1,
I only got into this hobby in 2006 and so I'm fairly green still. There has been a lot of great suggestions on this thread but I have a couple more that might help. Every loco I get goes through a series of test/improvements. I also check the amp draw to stall with a weight gauge designed to measurement the pull weight of the loco prior to stall speed. MicroMark has the gauge if your interested. It shows the max you can pull prior to stall speed/wheel slip/max amp draw. It's a bit over the top but I just like doing that as part of the hobby! I also do a final test prior to releasing the loco for duty on a 1.5% grade. If it can't pull at least twenty five properly weighted cars then it's back to the shop! I used to check the tractive effort by running the same train in the reverse direction of the grade. I don't know how that might help but it could give you some idea of where the wheel slip might start. Logically, if the wheels won't hold it back, then it won't pull either. This would also save your motors. Just some more input to help. Stephen
I haven't seen much (if any) here with regards to good reliable trackwork. Especially on a grade (which should have been very carefully planned as well as constructed), good high quality trackwork and consistency is required for reliable performance to be able to play a part. Slapdash methods using bargain-basement JUNK for track, and poor planning will almost (except for the very lucky) anways guarantee disaster-and God help you if the track in question is in a long tunnel. All the bullfrog snot in the world won't help this kind of problem.
RIch
Owner, president and chief cook and bottle-waasher of
THE PORTSMOUTH TERMINAL AND HOOSIC RR co.
You are right, there is not much regarding trackwork mentioned here, I assume because trackwork is probable recognized as not the issue. Effective troubleshooting is to only consider the probable items which affect the overall problem and not confuse the issue with things which are most likely not the fault. In this case, I don't think track work is the problem, because only one engine is affected. The problem only comes into play when the EM1 is pulling up the grade. The same problem is not occurring with the same cars being pulled up the same grade by:
(1) Bachmann F7A Erie Lackawanna diesel
(2) Bachmann F7A Erie Lackawanna and (1) Erie Lackawanna F7B diesel consist
(1) Bowser Alaska F7A diesel
(2) Bowser Alaska F7A diesels consist
(1) Bachmann Rio Grande EMD SD40 diesel
(1) Bachmann Alaska EMD SD40 diesel
(2) Bachmann Alaska EMD SD40 diesels consist
(1) Riverossi 4-6-4 Hudson Steam Engine w/ traction tires
(1) Riverossi 2-10-2 B & O Steam Engine w/ traction tires
I can fairly assume that if all these engines or engine combination are working just fine on the grade, and I am certain I have not purchased cheap bargain basement junk for track and put it together in a slapdash method. Even though I agree that all the BFS in the world will not help this situation, I have comfortably eliminated this condition.
I have also, as I previously stated, disregarded the probability that the EM1 has a design flaw.
To me, this means that my problem most likely is in the EM1's traction, like maybe dirt or oil on the traction wheels, for which I have ordered the equipment to do a really good wheel cleaning job, the EM1 has a gearing or gear alignment problem on this single engine, or this single EM1 engine may have a weak motor or the EM1 tender may be dragging wheels causing more resistance than the others are seeing. Or something else.
Something else could also be the EM1's speed vs torque curve. If the EM1 is not moving at a high enough speed to generate enough sustaining torque to maintain speed at this condition, it will slow down, and it may easily be confused with traction slippage. Remember, the EM1 has a single motor to drive all 8 axles, or 16 wheels. That's a lot of gear resistance. It may be the EM1 needs to be moving faster to generate enough torque to do this while the smaller engines are already working well into their torque curve at this speed and have far less gear and wheel resistance to deal with.
The pull test of my engine at the Suncoast Model Railroad Club layout hopefully may be completed this evening. It may simply be, the 3% slope is just too much for the EM1 at slow speeds as the Bachmann suggests.
i find it interesting thet the model em1 has trouble on a 3% grade, as the real ones worked cranberry in west virginia which was almost thet steep, i believe 2.7%......
one thing in your list of locomotives leaps out at me: the em1 is by far the biggest locomotive on the list.
are the wheels actually slipping or does it just lug on the grade? if it's not slipping the motor is probably too weak for the job, as you've surmised. but another possibility is that the locomotive is binding somewhere. since i don't have an em1 to test, this is only speculation. but what might be happening is that the em1 is not articulated enough in the vertical plane. that is, the two sets if drivers do not pivot up and down the way a diesel's trucks do. not really a problem with smaller steamers, but with a very long wheelbase like the two sets of drivers on the em1. not all wheels may be in contact with the rails anywhere the grade changes. one would think this would also be accompanied by a derailment problem in those areas, but it is something to look at.
Jeffery,
The place on the track where the problem is occurring is not where the slope starts or stops, it is in the center of the grade and the slope is very even and constant. BUT YOU DID MAKE ME LOOK AT SOMETHING I NEVER TOOK INTO ACCOUNT!
I notice a significant amount of turning resistance on the EM1 while passing through curves, even on flat curves, because the wheelbase is so long, even being articulated. All of my slopes are on curves! Running on the only track on this layout with turning radius large enough for the EM1 to maneuver, the engines are either pulling up or driving down 3% slopes, all on 22"R curves. The diesel's trucks turn much tighter with the curves and the smaller steam engines are only half the length of the EM1's wheels. I am willing to bet, the combination of the slope plus the added significant resistance in the turn on such a long wheel base, is requiring more throttle to maintain speed, which is exactly what I am seeing.
We had company this evening and I did not make it to the Club to test run the engine, but I am willing to bet the EM1 pulls like crazy on the club's incline, because the incline there is all on straight track. If this turns out to be the case, I am satisfied, and will just have to run it with slightly more throttle, of which there is plenty available to give to it. I will post after the test.
rb-
I'll bet that your anaylsis of the compounding problems for your EM is right on the mark. Often these impediments are worse than merely
additive; they can amplify one another. The big railroads had tables and formulas about the effects but all we can do with our minies is
guesstimate.
I don't have an EM but my impression from many posts about it on this board lead me to believe that the model is a little disappointing as a puller. I'm sure somebody will staighten me out about this if my impression is wrong.
-- D
Right now I wouldn't say it is disappointing as a puller, as I have seen it pull 30+ cars over at out Model Railroad Club. Although it will perform on 22" incline curves without any derailment problems, I think I have placed it in a specific environment where it cannot flex it's muscles as well as it can on either straight track or say 28" inclined curves.
However, I do have 28" curves for it on my permanent layout, which is still in the design phase. I will just need to give it more throttle than the others when it is used on the Christmas layout which is restricted to 22" curves.
Hi rbryce,
Your first post in this thread says that the loco slows on the grade, but you can't tell if it's spinning it's drivers or not. I would think you should be able to see and hear if it's a slipping problem, and if the wheels aren't actually slipping, then BFS is not going to help, and will only gum up a set of wheels, possibly reducing electrical pickup in the process. You go on to say (I think) that with added power it will make it up the grade with it's string of cars. Needing to add power to go up a steep grade sounds like fairly normal behavior, unless the loco is equipped with BEMF, in which case the BEMF should eliminate or reduce the need to add power going up the grade. Are you operating the loco on your home layout using DCC? Does your loco have a factory decoder with sound, or is it an after market installation? Do any of the other locos you are comparing the EM-1 to on the incline have BEMF?
Bill in FtL
Bill,
Lots of questions, hope I have the answers. First, I have no DC engines.
Are the wheels actually slipping, I don't know for sure, I just know the engine slows down. I cannot hear anything, but I've never heard this before, so I may not know what to listen for.
I can't say for sure, as where I am now I don't have the manual, but I would be extremely surprised to find it does not have BEMF. It does have sound and it does have the factory decoders.
That being said, I really think my problem is the particular layout design I have been running the engine on. This layout was never meant to run an engine like the EM1 because I never thought I would own one. It was meant for large diesel consists (2-4 diesels), and it's slope is also on a curved section of track. I have never had a problem with any size train using the diesels or the shorter wheelbase steam engines. I knew that turns impose resistance on an engine, and I knew that the slope imposed resistance on an engine, but I did not anticipate the combination of the two may not be simply additive, but compounded exponentially, as it seems to be, especially on really long wheelbase engines like the EM1.
The last thing that was on my get list was a really big steamer. When I saw the EM1 and the Big Boy, I started thinking about it, but the cost was really up there. At a recent train show, I found a new, sound equipped EM1 for an amazing price, and I broke down and bought it.
As I said either earlier in this post or on one of my other posts, the layout I have right now is a temporary Christmas layout, but as soon as it is relocated to the Living Room, we start building a permanent layout in the "train room" as we now call it. The Christmas layout will be placed in storage until the next season. The EM1 was purchased for the future permanent layout.
I really believe we have solved the issue of why the EM1 is having a hard time pulling up this particular incline, and that is because I not only have a fairly steep incline, but also because I am running it on a curved section of track with the minimum recommended 22" radius. I really believe the combination of the two is putting much more resistance on this engine than it would normal encounter without the operator giving it more throttle. With more throttle, it does gain some momentum, but I still can't determine if the wheels are actually slipping and causing some loss in traction.
After experiencing this, the new layout will be much more "EM1 friendly".
on a steamer like the em1, it should be very easy to tell if it is slipping or not. note how fast the side rods move on level track, in relation to the speed the locomotive is moving. when you get it to the grade, if it is slipping the rods will be moving much faster than the speed would indicate. if the rods slow down when the engine slows down, you are not slipping.