Issues with Otto

JimmyB

JimmyB

Phase 1 complete, roll on Phase 2
23 Feb 2018
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My Otto stopped a couple of times today, I know dirty track or wheels, however the light on the loco remains on, which suggests it is picking up power, and it was more of a “wiggle “ to get it going, so I am thinking dirty commutator or similar.
 
dunnyrail

dunnyrail

DOGS, Garden Railways, Steam Trains, Jive Dancing,
25 Oct 2009
14,442
197
71
St.Neots Cambridgeshire UK
My Otto stopped a couple of times today, I know dirty track or wheels, however the light on the loco remains on, which suggests it is picking up power, and it was more of a “wiggle “ to get it going, so I am thinking dirty commutator or similar.
Is it an oldish Second Hand one? There have been a few threads about restoring LGB Motors. However another thought occurs, are all of your points passing current OK on the cross wires within them? R3’s can be notoriously tricky in that respect with R1’s not much better. I find it well worthwhile to solder Jump Leads to replace all of the LGB wiping and stamped links for power. A reduction of power could certainly cause such issues.
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
22,504
169
Tamworth, Staffs.
Lights may be on, but are they dim?

1. Dirty track. - Inside edge on points.
2. Check power on switch-blades.
3. Dirty treads/tyres.
4. Clean wheel-backs where the plungers contact. - You don't have to be too vicious, but it does make adifference.
5. 'Ridges' in the carbon brushes? - Causes them to catch, and not make contact with wheel-backs.
 
Zerogee

Zerogee

Clencher's Bogleman
25 Oct 2009
16,452
33
North Essex
Remember that Otto uses the "Toytrain" gearbox rather than the standard LGB one, and doesn't have the classic Buehler motor but a more basic type - that doesn't actually impinge on the problem you're having, but I just mention it because any motor cleaning/repair articles that apply to the Buehler may not be relevant to the motor in the Otto.....

Jon.
 
P

perpetualnewbie

Registered
30 Apr 2019
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I don't really know how to deal with this sort of thing without popping the case off and taking a multimeter to it to find out if the supply of volts is making it all the way to the business end. Do you have one? (Cheapest kind will do for this). The problem with basic can motors (as opposed to named types) is there are so many sizes and specs you sometimes have to be a bit lucky to find a replacement, but fingers crossed - it's just as likely not to be that kind of problem.

Coming from smaller train sizes I have a bit of a distrust of pickups - though the plungers we have at G size seem a lot more robust, I'd still check that first. The motor probably needs a lot more current than the lamps so it might be possible for a weak connection to cause the motor to stall out without total light loss. Now, I've never done this in G, but in OO... you can test a motor in isolation by croc-clipping a SMALL analogue train supply right to its terminals and turning it up gently. After all, the circuit is the same as normal running, just with a much easier conductor path. I can't see a reason for this to be different at larger size, other than that the highest-amperage G scale stuff has enough current to really get things warm and might be best avoided. Every time I tried this, it showed the problem wasn't really the motor. Wires that have crimped or screw connectors can work loose or corrode, and are worth checking over.
 
JimmyB

JimmyB

Phase 1 complete, roll on Phase 2
23 Feb 2018
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Weston-super-Mare
Thanks, all it will get a bit of a strip down and a run on the rolling road. the odd thing about the stopping was it would just stop, no stutter, slowdown or the normal dirty track, and the gentle push did nothing. it was if the power supply had been cut, but then saw the front lamp was still lit.
 
JimmyB

JimmyB

Phase 1 complete, roll on Phase 2
23 Feb 2018
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So on to the rolling road, and no pickup on either front wheels, nice clean with mild solvent on the metal parts, and intermittent pickup, bottom plate removed and no "fixed" connects, just simple pressure contact, clean, a little (very little) copper coate (other makes are available) and back together. Runs appallingly - remember to set the quartering back doh!!
Now seems fine!
 
P

perpetualnewbie

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Glad to hear it! Thank goodness - seems like something easier to tackle than motors and brushes. I'm not sure I know "copper coate" (or "copper coat"?) other than as a marine anti-fouling paint... is it that? (it does seem to have enough copper content to be conductive...) or is it something else?
 
JimmyB

JimmyB

Phase 1 complete, roll on Phase 2
23 Feb 2018
1,384
95
65
Weston-super-Mare
Copper Coate/Crest there are number of copper based greases, though not strictly grease, it is used on brake components including liners to stop squeal, electrical component (lead acid batteries) to prevent corrosion, and on assemblies to prevent bi-metal corrosion, so this maybe the same anti-fouling mixture!
 
P

perpetualnewbie

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Thanks Jimmy. Hmm, probably not the same stuff. I'm not much of a (1:1 scale) mechanic and seem to have missed this - that is, I knew you could get greases with various loads, but didn't know there were copper ones that were meaningfully conductive. Shall have to pick some up. Thanks!
 
maxi-model

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
27 Oct 2009
4,408
57
Bucks/Oxon/Northants area
Or you can use the graphite based products marketed by LGB/Massoth and others for this purpose. I use both the copper and graphite products. All the track joiners/clamps and electrical connections are treated this way on my line.

Little tip with "pressure contacts". If practical solder them up. I had a USAT train block (destined for my OcCre Madrid tram) that refused to run properly, internally there were a number of bent brass rod busses only making contact with other electrical components through pressure or interference fits. I soldered them up, problems gone. Probably done as means of rationalising production of the block initially.

You might want to take a multimeter to your track and see if there are any significant drops in track voltage at any points, particularly at track joins. When I started running my Accucraft K-27 I discovered all sorts of problems, due to its unusual pick up arrangement - pickups one side only loco, other side tender only, that all my other locos never experienced with their "all wheels" pickups. Even ended up adding a booster cable that I had never needed in 15 years of use.

As I believe you use the Train Engineer you might also want to look to adding a 100 ohm/10 watt resistor across the 5471 controller's output leads. Recent thread, with appropriate drift, here Issues with Aristo 5471/5473 rx/tx - G Scale Central explains all.
 
P

perpetualnewbie

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I know the graphite grease, the copper stuff is new to me, if I get hold of some I will be measuring the difference. 100% agree on the benefits of a drop of solder in practice. Properly crimped connections are also excellent but anything just lightly pressed together seems to invite slow creeping failure over time.
 
JimmyB

JimmyB

Phase 1 complete, roll on Phase 2
23 Feb 2018
1,384
95
65
Weston-super-Mare
Or you can use the graphite based products marketed by LGB/Massoth and others for this purpose. I use both the copper and graphite products. All the track joiners/clamps and electrical connections are treated this way on my line.

Little tip with "pressure contacts". If practical solder them up. I had a USAT train block (destined for my OcCre Madrid tram) that refused to run properly, internally there were a number of bent brass rod busses only making contact with other electrical components through pressure or interference fits. I soldered them up, problems gone. Probably done as means of rationalising production of the block initially.

You might want to take a multimeter to your track and see if there are any significant drops in track voltage at any points, particularly at track joins. When I started running my Accucraft K-27 I discovered all sorts of problems, due to its unusual pick up arrangement - pickups one side only loco, other side tender only, that all my other locos never experienced with their "all wheels" pickups. Even ended up adding a booster cable that I had never needed in 15 years of use.

As I believe you use the Train Engineer you might also want to look to adding a 100 ohm/10 watt resistor across the 5471 controller's output leads. Recent thread, with appropriate drift, here Issues with Aristo 5471/5473 rx/tx - G Scale Central explains all.
I did read that thread with interest, though couldn't wholly see the benefit of the resistor, except to add a permanent load.
 
maxi-model

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
27 Oct 2009
4,408
57
Bucks/Oxon/Northants area
I did read that thread with interest, though couldn't wholly see the benefit of the resistor, except to add a permanent load.
It's a neat simple low cost fix to a known issue with the TE. It's one less thing to have to check if a loco does not seem to respond to commands from the handset and you get some strange readings from your multimeter when you try to diagnose. I've had my TE 16 years and never had the problem before. Had me scratching my head and fearing that I might need to replace my kit. Then somebody here pointed me to - TE Programming - Strange thing is I'd bookmarked the page years ago but never paid that much attention to it. Mr Schrayer's site is a very useful one for us LS fans. Max
 
JimmyB

JimmyB

Phase 1 complete, roll on Phase 2
23 Feb 2018
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Max, many thanks, interesting read, so the resistor goes across the output connections on the back of the receiver.
 
maxi-model

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
27 Oct 2009
4,408
57
Bucks/Oxon/Northants area
Post 31 of that thread indicates that the TE started working fine BEFORE he even bought the resistor.

Read a bit more in depth and you will see that he fixed/replaced the output fuse holder.

Greg
That is so Greg. However, what caused the issue experienced and described in the first place (as I understood it) was indicated to be down to a known "shortcoming" with the TE that can be avoided by the fitting of the resistor on the output terminals. I do not pretend to understand its function or how it alleviates the issue. I offer the link to Mr Schreyer's pages, as they were to me, so that another can make what they will of it and act as they see fit. It's just a case of "forewarned is forearmed". It's low cost and I do not believe its fittement can cause other issues, otherwise I assume Mr Schreyer would have added a caveat.

The mention of the refitting of the track side 10 amp fuse I think was incidental and a separate issue - a bit of a red herring. When I use the TE with my rolling road, as when the posted issue occured, I was not using the cable that had had that fuse deleted some years previously (stupid I know, I broke the fuse holder and chose not to replace it then). OK, the dedicated cable for the rollers does not have a fuse too, but it never has in all the years when I used it when test running locos and never resulted in the fault reported - till then. Maybe I should add a fuse to that too. Max
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
22,504
169
Tamworth, Staffs.
Maybe I should add a fuse to that too. Max
For your 'test' track.. A fuse would be a very good idea.

You are more likely to create a problem whilst 'fiddling', and it is cheap insurance. - Use a low value (couple of amps) fuse.


Fuses are there more to protect the equipment feeding the circuit (and people, if talking mains). When the fuse goes, it is quite often too late to protect the end-device. :nerd::(
 
Greg Elmassian

Greg Elmassian

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Max, what I am reading here and on George's site does not jive with what you are saying, so I'm trying to figure this out.

So the problem of the loco with the light on but the loco suddenly cutting out is gone, and before the resistor was fitted... that is there from the OP

The resistor on the output of the TE is to basically "zero out" the small voltage (actually leaky current) from the FETs in the TE, which is also not part of the original problem from the OP.

I do indeed understand Mr. Schreyer's site and this particular "fix" which was to bring the "idle" voltage to zero when the throttle was zero. (p.s. I have been face to face with him several times and he has visited my railroad)

The resistor fix can have nothing to do with the abrupt cutting off of the motor, as the headlight would go off also if the power quit, and in addition the "TE problem" is not having power cut out, but quite the opposite, never actually going to zero when desired.

So, after re-reading everything, I surmise there was a bad connection somewhere, perhaps the fuse holder, which could not pass current at some point, which is typical of a oxidized connection or a connection with a very small contact point that can limit current. It appears that has been fixed.

Basically voltage can be measured with very little current flowing, but when significant current flows, this situation can change, (again that is the resistor idea, the FET's leak a bit, and the resistor "bleeds off" the small current, thus bringing the output voltage to almost zero).

Best,

Greg