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DCC Locomotives Stalling on Turnouts

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Posted by richhotrain on Saturday, November 30, 2019 6:11 PM

corsiar

Happens on all of the unifrogs. The electrofrogs are ok. 

I didnt power the frogs or wing rails on the unifrogs so they are basically insulfrogs right now.

If there are two locomtives on the layout the head lights on the loco that is sittig its lights stay on and or prime mover sound never stops. 

Frogs seem deep enough because the wheels will fall in the gaps. Some had high points on the frog those got filed down. 

Hmm, all of the Unifrogs, and the lights and sound stay on. So, neither stalls (for lack of power) nor shorts (for opposite polarities). It does sound like sonething physical rather than electrical. Turnouts or locos? Who knows. You are going to have to look more closely at the problem. Do the locos ever start moving again on their own or do you have to lend an assist?

Rich

 

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Posted by BigDaddy on Saturday, November 30, 2019 6:29 PM

richhotrain
corsiar

Happens on all of the unifrogs. The electrofrogs are ok. 

I didnt power the frogs or wing rails on the unifrogs so they are basically insulfrogs right now.

If there are two locomtives on the layout the head lights on the loco that is sitting its lights stay on and or prime mover sound never stops. 

Frogs seem deep enough because the wheels will fall in the gaps. Some had high points on the frog those got filed down. 

 

 

Hmm, all of the Unifrogs, and the lights and sound stay on. So, neither stalls (for lack of power) nor shorts (for opposite polarities). It does sound like sonething physical rather than electrical. Turnouts or locos? Who knows. You are going to have to look more closely at the problem. Do the locos ever start moving again on their own or do you have to lend an assist?

Rich

I don' know he means neither as he has also said if the sound is on, they stall going through the turnouts, if it sound is off, they don't.

 "The loco that is sitting" I take to mean the one that retains sound.  I've read about people jumpering the point rails to the stock or closure rails.  I don't know enough about unifrogs to know if that is the problem. 

Henry

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Posted by corsiar on Saturday, November 30, 2019 9:42 PM

Maybe I should hae asked this question earlier. How slow should a sound locomotive be able to go through a turnout without stalling? Right now they stall at speed step 1-2 which I have set at about 1 tie per sec. 

 

Most of the time they just hesitate for a sec then start going again on their own. Sometimes they will stop and if I just barely touch it will start up again.

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Posted by Doughless on Saturday, November 30, 2019 10:45 PM

corsiar

Maybe I should hae asked this question earlier. How slow should a sound locomotive be able to go through a turnout without stalling? Right now they stall at speed step 1-2 which I have set at about 1 tie per sec. 

 

Most of the time they just hesitate for a sec then start going again on their own. Sometimes they will stop and if I just barely touch it will start up again.

 

IMO, they should go through turnouts on speed step 1.  What I don't understand is this, usually stalling on turnouts happens when one truck is over and unpowered frog.  But with a six axle diesel, there should be enough length to the truck and the locomotive so that they find electrical current from other rails on the turnout.  So your problem is mystifying to me.

There may be a problem with flange width or wheel gauge on some locos going through unifrogs, and they bind just enough.

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Posted by richhotrain on Saturday, November 30, 2019 11:28 PM

BigDaddy
 
richhotrain
corsiar

Happens on all of the unifrogs. The electrofrogs are ok. 

I didnt power the frogs or wing rails on the unifrogs so they are basically insulfrogs right now.

If there are two locomtives on the layout the head lights on the loco that is sitting its lights stay on and or prime mover sound never stops. 

Frogs seem deep enough because the wheels will fall in the gaps. Some had high points on the frog those got filed down.  

Hmm, all of the Unifrogs, and the lights and sound stay on. So, neither stalls (for lack of power) nor shorts (for opposite polarities). It does sound like sonething physical rather than electrical. Turnouts or locos? Who knows. You are going to have to look more closely at the problem. Do the locos ever start moving again on their own or do you have to lend an assist?

Rich 

I don' know he means neither as he has also said if the sound is on, they stall going through the turnouts, if it sound is off, they don't.

 "The loco that is sitting" I take to mean the one that retains sound.  I've read about people jumpering the point rails to the stock or closure rails.  I don't know enough about unifrogs to know if that is the problem.  

What I meant by the word "neither" is that the problem loco neither stalls nor shorts for electrical reasons, not that neither loco stalls nor shorts. I was focusing on the loco that stopped on the turnout. Maybe the OP is just too imprecise in describing the problem, leaving us to do nothing more than speculate as to the cause of the problem.

Rich

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Posted by corsiar on Sunday, December 1, 2019 12:48 AM

Trying my best to desribe the issue. Pics are always better. This is the problem spot. With the distance between frogs and the wheel spacing probably not much more I can do. This locomotive will go through 90% of the time at speed step 1.

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Posted by richhotrain on Sunday, December 1, 2019 5:29 AM

corsiar

Trying my best to desribe the issue. Pics are always better. This is the problem spot. With the distance between frogs and the wheel spacing probably not much more I can do. This locomotive will go through 90% of the time at speed step 1.

 

I will give you that. You are trying your best to describe the issue. The problem here is that we have all been unable to eliminate any possible causes, so it could be the loco itself, the turnout, or an electrical issue.

1.  What happens if you physically turn the loco around and run it throught the turnout from a different direction? Try to locate the exact spot on the turnout where the stall/short occurs.

2.  Are both the front and rear trucks picking up power from the rails? I have seen this more than once where either the front truck or rear truck is not picking up power.

3.  Is there power between the frogs shown in that photo? When I have experienced a problem like stalls at slow speeds over turnouts, I will get out some test wires with alligator clips at both ends of the wires. Then, I will connect one end to a straight section of track and touch the alligator clips on the other end to various rail segments on the turnout to see if the loco will move.

Rich

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Posted by richhotrain on Sunday, December 1, 2019 5:38 AM

corsiar

Happens on all of the unifrogs. The electrofrogs are ok. 

I didnt power the frogs or wing rails on the unifrogs so they are basically insulfrogs right now.

If there are two locomtives on the layout the head lights on the loco that is sittig its lights stay on and or prime mover sound never stops. 

Frogs seem deep enough because the wheels will fall in the gaps. Some had high points on the frog those got filed down. 

I want to go back to this reply. Interesting that you use a mix of Unifrogs and Electrofrogs and that only the Unifrogs fail. Any chance of swapping an Electrofrog for a Unifrog as a test or are all of the turnouts soldered?

How large is this layout and how many turnouts do you have on the layout? How many of the turnouts are Unifrogs and how many of the turnouts are Electrofrogs?

Are there only 4 locomotives that you run on this layout at the present time? You mentioned in your initial post that you own four brands, KATO, Scaletrains, Intermountain, and Broadway Limited and that only the Broadway limited and Intermountain stall on turnouts. Do you own just one of each brand?

Rich

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Posted by Doughless on Sunday, December 1, 2019 10:45 AM

corsiar

Trying my best to desribe the issue. Pics are always better. This is the problem spot. With the distance between frogs and the wheel spacing probably not much more I can do. This locomotive will go through 90% of the time at speed step 1.

 

So the problem may be better described as a couple of your six axle diesels stall when going through two frogs (turnouts) at once?  I was thinking they were stalling only on one turnout (at a time).

The spacing of the frogs suggests that only alternate sides of two trucks are getting power since the loco is spanning two frogs at once.  The turnouts look like they are NOT electrofrogs, given the black gaps in the rails. But the trucks should be long enough so that its front and/or rear wheels pick up power before or beyond the frog.  (BTW, certain older vintages of KATO SD40s had some electrical pickup problems. You can search this on the 'net probably.  If this is an aftermarket install of a sound decoder, a less than professional install combined with factory shortcomings may produce intermittent stalling.  Can't comment on the BL loco.)

So the loco is in fact stalling when the trucks traverse two unpowered frogs at the same time, not just one, correct? 

If it is an electrical stall, the wheel axles may not be picking up current if there is dirt or fuzz or debris where the axle tips stick through the phosphorous pickup bar on the inside of the truck frame (look to see how these trucks are assembled)  You may have to take the truck cover off and clean the trucks.

However, you've implied that the stalling does not cause the lights or sound to cut out at all, not even for a flicker, correct?

If its not an electrical stall, the black guard rails have the same spacing as the frogs, so it might not be a frgo problem at all.  If the flanges of the loco are too narrow, maybe even too wide, or are too thick, the space between the black guardrail and the stock rail may be pinching the wheels, causing the guard rail to act like a brake just enough to occasionally cause a stall of movement but nothing else.

 

- Douglas

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Posted by corsiar on Sunday, December 1, 2019 1:03 PM

Seems to be an electrical stall from the wheels not being able to contact the rails. The stall is only at slow speed, speed step 1-3 anything above that no problem.

 

The layout is 9' x 10'. Used both electrofrogs and unifrogs because PECO doesnt make a medium readius code55 turnout anymore. Didnt have space to use all large radius electrofrogs. Layout in process of being built. I test each section of track as I lay it. Every joint is soldered except the electrofrogs has gaps at the frog point rails.

 

This is my current locomotive roster.

2ea   Intermountain SD40-2 with LokSound

1ea   BLI SD70ACe paragon 3

1ea   Scaletrains GEVO tier 4 with LokPilot

1ea   Scaletrains GEVO tier 4 with LokSound

1ea   Kato SD70ACe wih TCS

1ea   Kato SD70ACe no decoder

1ea   Kato FEF no decoder

2ea   Kato AC4400CW no decoders

2ea   Kato ES44AC no decoders

1ea   Kato SD40-2 no decoder

1ea   Atlas MP15 no decoder

 

 

All the turnouts in this pic are unifrogs.

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Posted by Doughless on Sunday, December 1, 2019 2:28 PM

If the wheels are still failing to contact the rails as the loco moves, then I would say that a physical/mechanical issue is the root of the problem.

We've talked about several possibilities.  Uneven track, or the wheels/flanges being affected by being too narrow or too wide causing a lift for some reason.

If someone has thought of other possibilities, now would be a good time to speculate.

- Douglas

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Posted by richhotrain on Sunday, December 1, 2019 2:59 PM

Doughless

If the wheels are still failing to contact the rails as the loco moves, then I would say that a physical/mechanical issue is the root of the problem.

We've talked about several possibilities.  Uneven track, or the wheels/flanges being affected by being too narrow or too wide causing a lift for some reason.

If someone has thought of other possibilities, now would be a good time to speculate. 

When these kinds of issues come up in these kinds of threads, there is a need to eliminate as many causes as possible - - - the process of elimination. 

As I said in an earlier reply, the problem here is that we have all been unable to eliminate any possible causes, so it could be the loco itself, the turnout, or an electrical issue. So, let me repeat three possible approaches to narrowing down the list of possibiities.

1.  What happens if you physically turn the loco around and run it throught the turnout from a different direction? Try to locate the exact spot on the turnout where the stall/short occurs.

2.  Are both the front and rear trucks picking up power from the rails? I have seen this more than once where either the front truck or rear truck is not picking up power.

3.  Is there power between the frogs shown in that earlier photo with the loco laying on its side? When I have experienced a problem like stalls at slow speeds over turnouts, I will get out some test wires with alligator clips at both ends of the wires. Then, I will connect one end to a straight section of track and touch the alligator clips on the other end to various rail segments on the turnout to see if the loco will move.

At the moment, we are at an obvious impasse.

Rich

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Posted by corsiar on Sunday, December 1, 2019 9:39 PM

The stalling is random. I have trouble repeating the stalls to narrow down the issue. Have narrowed it down to happening between two turnouts close together like a crossover or two turnouts connected together.

 

Front and rear trucks are picking up power but I am guessing all the wheels on the trucks are no getting power or wouldnt have this problem.

 

According to the volt meter there is power between the turnouts. 

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Posted by rrinker on Sunday, December 1, 2019 10:11 PM

 Random implies intermittant electrical contact cuased by the weight of the locomotive.

 In your picture, if that is exactly where it stalls - the top side (conductor's side - I was going to say fireman's side but since it's a modern loco..) rear truck, to the right of the pic, could have all 3 wheels on questionable track, since the only power to the point and closure rails is via the point rail contacting the stock rail.

 The other thing I saw mentioned - if there are gaps in the rails past the frogs, are there feeders to the rails between those turnouts? Otherwise, that entire section is dead as a doornail. It's perfectly fine to have feeders on the frog side of even an Electrofrog turnout - AFTER the gaps. In fact, you pretty much have to,especially in a crossover arrangement, or the track past the gaps is completely dead, unless backfed via the opposite side of the loop.

 The easiest way to find out where the dead spot is, is to use a small flat screwdriver, and when the loco stals, touch various points  with the screwdriver - when you bridge power from the powered part to the rail the wheels are on that has no power, the loco will start moving.

I would wire all Unifrogs to work like Electrofrog, with polarity control via switch machine contacts. The more rail in the turnout that has a positive power source, the more reliable it will be. The optional modifications to provide direct power to the point and closure rails also can't hurt, especially for N scale.

                                --Randy

 


Modeling the Reading Railroad in the 1950's

 

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Posted by corsiar on Sunday, December 1, 2019 11:18 PM

Here is a pic of the back side of a unifrog. The closure rails have jumpers to the stock rails. The rails after the frog point has one jumper from the stock rail the other from the straight closure rail. 

 

 

Going to put feeders before and after the unifrogs in one section and see what happens.

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Posted by corsiar on Monday, December 2, 2019 11:59 PM

Installed feeders on both sides of the problem turnouts that was pictured with the locomotive on its side. That seems to have done the trick. Ran the locomotive over it for an hour on speed step 1 both directions changed directions between the turnouts, sound off and on and it wont hesitate or stop. Looks like I have a ton of feeders to put in.

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Posted by Doughless on Tuesday, December 3, 2019 10:09 AM

corsiar

Installed feeders on both sides of the problem turnouts that was pictured with the locomotive on its side. That seems to have done the trick. Ran the locomotive over it for an hour on speed step 1 both directions changed directions between the turnouts, sound off and on and it wont hesitate or stop. Looks like I have a ton of feeders to put in.

 

Glad you solved the problem.  However, I thought you mentioned the wiring was okay?

Just for future reference because the unifrog's are fairly new to the scene, do you think the problem was that you did not follow the wiring guidelines correctly (took short cuts), or do you have to add more wiring than the instructions call for?  Just to help out future readers.

- Douglas

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Posted by BigDaddy on Tuesday, December 3, 2019 10:40 AM

corsiar
Installed feeders on both sides of the problem turnouts that was pictured with the locomotive on its side.

Does that mean before and after the turn out or right and left sides of the turnout?

More electrons, what's not to like?

Henry

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Posted by richhotrain on Tuesday, December 3, 2019 10:43 AM

Doughless
 
corsiar

Installed feeders on both sides of the problem turnouts that was pictured with the locomotive on its side. That seems to have done the trick. Ran the locomotive over it for an hour on speed step 1 both directions changed directions between the turnouts, sound off and on and it wont hesitate or stop. Looks like I have a ton of feeders to put in. 

Glad you solved the problem.  However, I thought you mentioned the wiring was okay?

Just for future reference because the unifrog's are fairly new to the scene, do you think the problem was that you did not follow the wiring guidelines correctly (took short cuts), or do you have to add more wiring than the instructions call for?  Just to help out future readers. 

Yep, a lot of rabbit holes in this thread, warped turnouts, warped trucks, 6-axle locomotives, soldered rails, etc.

Turnout 101 Wiring: Add feeders on every end of every turnout. Even then, when stalling occurs on a turnout, check for continuity. I have a few Walthers Shinohara Double Crossovers with feeders on all four ends. But over time, some of the jumpers have failed resulting in unpowered rail segments.

As far as Unifrogs are concerned, they require no special wiring. I have four Peco Code 83 Unifrog Double Slips. No problems whatsoever. Just add feeders on every end of each double slip. 

Rich

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Posted by Doughless on Tuesday, December 3, 2019 12:29 PM

richhotrain

 

 
Doughless
 
corsiar

Installed feeders on both sides of the problem turnouts that was pictured with the locomotive on its side. That seems to have done the trick. Ran the locomotive over it for an hour on speed step 1 both directions changed directions between the turnouts, sound off and on and it wont hesitate or stop. Looks like I have a ton of feeders to put in. 

Glad you solved the problem.  However, I thought you mentioned the wiring was okay?

Just for future reference because the unifrog's are fairly new to the scene, do you think the problem was that you did not follow the wiring guidelines correctly (took short cuts), or do you have to add more wiring than the instructions call for?  Just to help out future readers. 

 

 

Yep, a lot of rabbit holes in this thread, warped turnouts, warped trucks, 6-axle locomotives, soldered rails, etc.

 

Turnout 101 Wiring: Add feeders on every end of every turnout. Even then, when stalling occurs on a turnout, check for continuity. I have a few Walthers Shinohara Double Crossovers with feeders on all four ends. But over time, some of the jumpers have failed resulting in unpowered rail segments.

As far as Unifrogs are concerned, they require no special wiring. I have four Peco Code 83 Unifrog Double Slips. No problems whatsoever. Just add feeders on every end of each double slip. 

Rich

 

Agreed. 

But its still a mystery as to why some locos were more susceptible to this and others were not.

If turnout joints are soldered, that can be as good as a feeder.  There are other reasons to not solder turnouts however.

- Douglas

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Posted by rrinker on Tuesday, December 3, 2019 3:15 PM

 Not much of a mystery. Exact wheelbase is not going to be the same, even if it's two brands of the same prototype. Or maybe some brands of 6 axle units pick up with only 4 wheels on each truck instead of all 6. ANd in those cases - is it the two outside axles that pick up, or the two nearest the ends, or the two nearest the center? There's enough minor differences like that between different brands of locos that allows one brand to hit a spot where both sides of both trucks are on dead spots, whereas another brand will always have at least one wheel on each side on live track and thus never stalls. 

Could even be a pickup problem - in that it's SUPPOSED to pick up from all 12 wheels but it's not pickup up power from one side of one of the trucks at all because the pickup wipers aren't making contact, or something. So with the extra feeders, there's no dead spot for the working pickup to get stuck on, but if all pickups were solid, it wouldn't have stalled in the first place. This is easy to test - put the lead truck on a piece of paper, rear truck on the rails, see if it runs. Repeat with the paper under the rear truck and the front truck on the rails. Any loco that says it has all wheel pickup should work fine with one whole truck insulated from the rail. Then you can see just how far you can go but putting one whole truck on the paper and then putting one, then two axles of the other truck on paper. As long as one pair of wheels is touching the track - it should work. 

                                              --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by corsiar on Tuesday, December 3, 2019 4:19 PM

What is the thought about putting dielectric grease on the wheel pivots? There is play in the wheel pivots or they would not turn. Maybe something to always conduct electricity even if the pivot is not touching the copper pickup.

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Posted by BigDaddy on Tuesday, December 3, 2019 4:39 PM

The purpose of dielectric grease is to prevent corrosion not to enhance electrical conductivity.

In a motorcycle, if you have a male-female crimp on connector, there is part of the connectors that don't make contact with each other, but if that area develops corrosion, it can spread to areas that do make contact.

There are conductive greases.  100% contact would be better.

Henry

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Posted by richhotrain on Tuesday, December 3, 2019 4:42 PM

corsiar

What is the thought about putting dielectric grease on the wheel pivots? There is play in the wheel pivots or they would not turn. Maybe something to always conduct electricity even if the pivot is not touching the copper pickup. 

Is it intermittent contact or a lack of power? Now that you have added feeders to all three ends of the problem turnouts, has that not solved the problem?

Rich

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Posted by corsiar on Tuesday, December 3, 2019 5:58 PM

I did feeders at two problem turnouts. Going to do the same at another two and see if I get the same results. 

 

The locos with pointed axles are doing ok. Got a BLI and it has straight axles with a lot of clearence and need to get better conductivity. It stalls on straight flat track.

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Posted by corsiar on Tuesday, December 3, 2019 6:14 PM

I did feeders at two problem turnouts. Going to do the same at another two and see if I get the same results. 

 

The locos with pointed axles are doing ok. Got a BLI and it has straight axles with a lot of clearence and need to get better conductivity. It stalls on straight flat track.

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Posted by Doughless on Tuesday, December 3, 2019 6:38 PM

My original thought when reading this thread for the first time back on the first page was that the BL was probably going to be a bit quirkier than the other locos.  If it has problems that the others don't, there may not be much you can do about it.  I thought it was best to be sure the track work was bulletproof before guiding you to start tearing into a loco when its design might make it a bit more tempermental when compared to KATO, IM, and Scaletrains.

- Douglas

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Posted by richhotrain on Wednesday, December 4, 2019 4:56 AM

corsiar

Got a BLI and it has straight axles with a lot of clearence and need to get better conductivity. It stalls on straight flat track. 

We keep on coming up with more issues. This one is a bit easier to deal with than a stall on a turnout. This one is either a problem with the loco itself or insufficient power to the track. 

If the BLI is an N scale Paragon 3, which I assume it is, there are known issues here, and those issues relate to the decoder. The Paragon 3 decoder is a proprietary to BLI, and it has performance issues.

If the "straight flat track" is the problem, it can only be lack of power which is most often caused by lack of sufficient feeders, followed by poorly fitting rail joiners, or dirty track.

Does the BLI always stall at the same locations or are the locations random? 

Do any of the other locos stall on straight flat track?

Rich

Alton Junction

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