Getting bogie wheels to rotate after fitting pick ups.

[philsandy]

I am attempting to fit a single set of additional pick ups to the front bogie wheels of a Bachmann Standard 5 loco. I have them set contacting the backs of the flanges.

 

The pick ups work in that they are collecting current, but I can not get the loco to run without these wheels occasionally stopping rotating, ie. they slide along the rail now and again. The slightest of weight applied on the front coupling cures this, and the wheels then turn constantly.

 

I have adjusted the tension to a minimum. Also I thought that may be the Slaters phosphor bronze strip (0.12mm thick) was to stiff, so I used the pick ups from a spare keeper plate, these being slightly thinner (0.09mm). 

The wheels turn very freely when I spin them with my finger, there does not seem to be any drag on them.

 

A while ago I fitted extra pick ups to a Bachmann Standard 3MT and this worked perfectly first time. This has a  single axle front pony wheel, rather than the 2 axle bogie of the Standard 5, and I wonder if this is a factor?

 

Can anyone suggest a remedy?

[uax6]

How about a spring on the bogie pivot to forced the bogie down onto the track? Also are your wipers sprung in anyway? I would use p/b wire and put a loop in the middle of the wiper, so that the tip is very lightly sprung...

 

Andy G

[34theletterbetweenB&D]

A little graphite on the wheelback may help, either dust sold as a lubricant or from a 4B or softer pencil. Light oil or grease on the axle bearings too. This may sound perverse, but if the bogie still has the original spring Bachmann supplied acting on it, significantly reducing the spring force may help. As supplied there was about 50gf acting on the bogie which is very excessive and created considerable drag. Possibly this creates enough friction in the bogie bearings that a small increment in friction from the wiper is enough to stall the axle?

 

More work, but very reliable: consider instead collecting off the tender wheels? Using the older Bachmann split axle spoked wagon wheels you can collect off the pinpoints running in brass bearings, with no incremental friction. (OK they only have eight spokes instead of nine, but being well hidden behind the frames it really doesn't notice.)

[philsandy]

After spending several hours trying to get this to work, I have now got the front bogie wheels rotating constantly ... when going forward.

However in reverse, the wheels still intermittently stop/start turning.

I did adjust the bogie spring, by slightly lengthening it from 6mm to 7mm, to help to keep the wheels down on the track, this did improve running, albeit in one direction. 

 

I am mystified as to why the bogie wheels should rotate constantly when running in one direction, but not in the other?

Can anyone suggest a cause? 

 

 

[uax6]

Have you put a small v in the end of the pick-up where it touches the wheel back? If not the wheel may be getting caught on the end of the wire in the reverse direction.

 

Andy g

[DCB]

The not very obvious question is why?  I routinely take off extra pickups to reduce drag and increase the trains locos can haul.  Reducing the weight of a Hornby Black 5 Tender and removing the pick ups increased its haulage from 3 to 6 coaches up my bank, some way short of my 1960s Britannia which hauls 12 on the same grade.   I use a Relco and voltage regulated DC and don't clean the track very often..

 

Poor pickup is not the worst fault with my Bachmann Std 5, poor tractive effort and an inability to run at express train speed are bigger issues

 

Pickups need to bear on the axle on carrying wheels, rather than the flange. Ideally a split chassis bogie with split axle wheels.  mainline did some nice split axle BR standard bogie wheels which solves the biggest problem. Bushing the bogie with brass bushes is difficult  and making up brass sideframes bearing on the axles with insulated spacers may be easier.

 

I am doing the same thing with an M7 but can't find suitable split chassis wheels

[71000]

I 

[philsandy]

I understand your problem exactly. As I too have a number of Bachmann BR standard 5 locos. However knowing that adding pick-ups to pony/bogie wheels is irritating I have added pick-ups to the tenders on my models. 

 

Possible solution to your dilema.

If there is any space on the top of the bogie that won't foul the chassis above, adding weight to the bogie will reduce the problem you are having. Obviously this needs to be something dense such as lead, giving maximum weight in the smallest space. 

 

 

Thanks for all your replies.

 

I have improved running, not 100% perfect, but a lot better than it was. When running In reverse the wheels now only occasionally stop rotating. 

I put approx.10 grams of lead on the top of the bogie.

Also, the wipers are superglued to a tiny square of plastic, which was then held in position to the underside of the bogie with a blob of that black sticky stuff (sorry don't know what it's called, it's like Blu Tac only stickier). 

This was not holding the wipers in a fixed position, and was moving very slightly, so I superglued the plastic square to the bogie underside.

 

I wanted to avoid using the tender wheels to pick up, not because of the work involved, but the inconvenience of

having the tender and loco connected with a wire. Though I'm sure that this is the way to guarantee electrical pick up 100% of the time.

 

Have you put a small v in the end of the pick-up where it touches the wheel back? If not the wheel may be getting caught on the end of the wire in the reverse direction.

 

Andy g

 

Andy, I'm not sure what you mean, please could you elaborate, thanks.

[Titan]

 

 

Andy, I'm not sure what you mean, please could you elaborate, thanks.

 

                                                                                                                     

The end of the pickup should be shaped with a shallow V in the end like this   ___/\_   with the point of the V bearing on the back of the wheel.

[Classsix T]

In other words a bend in the pickup with a smooth surface bearing on the wheel as opposed to the end which might well have burrs to catch on wheel back imperfections.

 

C6T.

[nswgr1855]

I am attempting to fit a single set of additional pick ups to the front bogie wheels of a Bachmann Standard 5 loco. I have them set contacting the backs of the flanges.

 

The pick ups work in that they are collecting current, but I can not get the loco to run without these wheels occasionally stopping rotating, ie. they slide along the rail now and again. The slightest of weight applied on the front coupling cures this, and the wheels then turn constantly.

 

I have adjusted the tension to a minimum. Also I thought that may be the Slaters phosphor bronze strip (0.12mm thick) was to stiff, so I used the pick ups from a spare keeper plate, these being slightly thinner (0.09mm). 

The wheels turn very freely when I spin them with my finger, there does not seem to be any drag on them.

 

A while ago I fitted extra pick ups to a Bachmann Standard 3MT and this worked perfectly first time. This has a  single axle front pony wheel, rather than the 2 axle bogie of the Standard 5, and I wonder if this is a factor?

 

Can anyone suggest a remedy?

How about removing the extra pickups and try the proven electronic alternative of installing a DCC decoder ( I use Zimo decoders) with a storage capicator. TCS make what they call a KA3 'keep alive' capicator package that keeps your model moving from 6 to 20 seconds over dead track. No need for extra pickups that stop wheels turning and decrease the maximum length of train your locomotive can pull.

 

Cheers,

Terry Flynn.