Bachmann DMU pick-ups

[SwissRailPassion]

I have been experiencing poor running from my class 105 units and almost non-existent running from a 150 DMU. On opening the 150 I saw that the pick-ups are by brush contact rather than wires; this led me to solder wire to the pick-ups, and performance has now improved. The 105s were excellent runners in the 1st year, but recently they too have become erratic. A similar problem is the transfer of power using a contact rather than a soldered or hard-wired connection. This seems to me to be a design weakness and I have soldered the power bogie contacts.

Back in the eighties it was common to rewire and create extra pick-ups on Hornby stock to improve running, but to find this on such a high spec model made in 2011 is very disappointing. 

Has anyone else had similar problems?

Edited April 10, 2013 by SwissRailPassion

[Removed a/c]

Can't say I have had any problems with my 150s both run like a dream. 

[newbryford]

Has anyone else had similar problems?

 

Yes.

 

Cheers,

Mick

[Gwiwer]

No fault found on the class 150 fleet which continue to run as sweetly as when they came out of the boxes.  I don't have a 105 but both 108s which have a single-bogie motor require a little TLC just to keep the wheels and wipers clean including the unpowered wheels which also collect juice.

[Silver Sidelines]

105s, 108s, Derby lightweights and the Blue Pullman all use a similar system with power collection from both powered and unpowered wheels.  I have not had problems directly related to pickup.  I would second 'Gwiwer' comments and say that relative to 'steam' locomotives the wheels on DMUs do seem to get dirty.  I had thought it might be somehting to do with all the diodes for lighting. 

 

I would also say that there can be an issue with what I will call 'balance'.  If the copper contacts on the circuit board are not correctly or equally postioned the body of the DMU will not sit straight or at the correct level.  I would need to revisit this aspect if you are saying that you can remove the copper strips completely and replace with hard wire.

 

Regards

 

Ray

Edited April 11, 2013 by Silver Sidelines

[34theletterbetweenB&D]

... but to find this on such a high spec model made in 2011 is very disappointing. Has anyone else had similar problems?

 What I would see as expedients to make the assembly line process simpler, and quite likely less prone to incidental damage during assembly, has been increasingly evident in loco wiring arrangements on both Bach and Hornby product over the last half dozen years. What this consists of is soldering performed away from moulded plastic components enabled by use of sprung contacts or clip on connectors when assembling. From a production perspective I can see the benefit, no hot soldering iron at assembly stations where moulded plastic components are also present, the assembly is completely cold.

 

From this customer's perspective, it's retrograde as compared to good soldered joints in wiring. Once the model has been tested on receipt and proven basically sound, out comes the soldering iron and the electrical arrangements are revised to all soldered connections wherever possible.

[SwissRailPassion]

Good photo Newbryford - thanks. Good to see it's not just me that got out the soldering iron. I think the 105 and 108 design is clever as it gives interior lighting etc as well as the most discreet place for the motor. However the pick-up is the most important part of the design...

[stewartingram]

I too solder across the sprung points. You can't beat a good soldered connection every time. As I have to remove the bodies anyway to remove the lighting (not necessary on a green era vehicle) and detail the interior I do it then. I also add simple hook and loop close couplings, and hard wire across the 2 vehicles so it picks up on all wheels.

 

Stewart

[DavidParry]

• I'm having same problem with the 108 set as most of you! Loco ran extremely well for about a year then went into "random" mode! It would suddenly stop, go into reverse then forward again. I corrected this by soldering wires across the wipers from the bogie pickups which corrected the "balance" problem.  Fine for some months but now it's back to the old problem. Have cleaned the wheels and axle bearings, added wires to the trailing bogie but still the same problem - although not so bad! I have now added fine brass pickups on the trailing bogie which doesn't seem to help much. Next I removed the motor housing and find the brush contacts are not soldered but power is applied through brass wiper contacts which lightly press against them. Maybe this could cause the problem! Any thoughts please?

David

[cravensdmufan]

I have recently had problems with my Bachmann 101's which have began running erratically.  Wheel dirt does seem to be more of a problem with DMU's and Silver Sidelines' comment in post #5 regarding lighting diodes was interesting so I turned the lights off and the wheels do seem a little better after a week.  Time will tell.

 

However, today I have discovered another possible cause.  The trailing bogie of the power car is supposed to pick up it's juice via axles points in brass bearings which are linked to a couple of probes that stick up through the floor which should make contact with a pair of brass plates under the seats.  I discovered that my trailing bogie wasn't picking up too well, but I found an easy cure as follows:

 

1.  Remove body (4 small screws in each corner).

2.  Unclip black lighting PCB (by removing 4 black clips and 4 silver strips).

3.  Unscrew seating (4 tiny screws).

4.  Fold (3x) a small square of paper to make a springy cushion to go between the seats and the brass plates.  (This will hold the contacts tighter against the bogie pickup probes.)

5.  Re-assemble in reverse order of above.

 

Sounds too simple but it really works!  Power now picks up reliably from all 8 wheels!  

[34theletterbetweenB&D]

That will work for a while, but the paper will crumble and the trouble will then return. I have been through all my class 105s soldering on really fine wires to make all the connections, rock solid running.

 

On the positive side, the pick up from the pinpoints on these DMU's and the Met-Camm Pullman cars is a complete delight, free rolling with robust current collection. The Pullmans will 'detect' gradients on nominally level layouts, one of them gets away on what I estimate to be a 1 in 350. Since my set is decoder fitted for light control, I am thinking about a motor operated parking brake in the brake ends.

[cravensdmufan]

That will work for a while, but the paper will crumble and the trouble will then return. I have been through all my class 105s soldering on really fine wires to make all the connections, rock solid running.

 

On the positive side, the pick up from the pinpoints on these DMU's and the Met-Camm Pullman cars is a complete delight, free rolling with robust current collection. The Pullmans will 'detect' gradients on nominally level layouts, one of them gets away on what I estimate to be a 1 in 350. Since my set is decoder fitted for light control, I am thinking about a motor operated parking brake in the brake ends.

I hadn't thought of the paper crumbling.  If that happens I may try a square of Plasticard.

 

I don't trust myself with the soldering iron!

[AMJ]

On my Derby light weight I have wire connections (with plugs) between the two units similar to stewartingram, just like the distributed power collection in the Blue Pulman this vastly improves the running of it.  Previously I used to see lights go out on the trailer or power car stop on some dirty track.  (Note to self must clean track.)  As my DLW has sound it just keeps chugging away.

[cravensdmufan]

Meanwhile, 6 years later.....

 

Now having the same problem with my Bachmann Class 85, so it's out with the soldering iron this afternoon.  I'm more confident with the iron nowadays!