railcar1

The alignment of the side panel also affects the height of the support arm on that side.

Sad truth with many retailers is if it runs its fine!

Have a look at the Hornby  Mag.,March, booster review main picture,the fault is obvious to see.

As previously reported I have mitigated the issue by adding  shims.This fixes the wheels in contact  with track problem but not the underlying fault. 

In my  opinion the problem is the screwed on side panel of the gear tower is not aligned properly causing  the axles to sit out of true.

This may be a manufacturing issue or perhaps damage in transit. 

This problem does seem relatively  widespread. EFE should really respond. 

Fixed mine using 'three point suspension 'as others have done!

Would be very  interested  to know what this 'minor  manufacturing issue' is.

On 18/01/2024 at 20:59, jonnyuk said:

100%, perfect balance, does not need a fancy stay alive etc, no need for fans or raising pantographs, the livery finish is good, it’s a good runner, enough detail to look high end, except the inconsistent running (which I need to sort out with my local shop) I think it’s the best value loco I’ve ever bought.

Often pondered that one myself CJL.

Mine is the black one. Same  problem,only 8 of 12 wheels touching the track!

In my opinion the chassis  casting is fine as are the bogies generally speaking. 

The fault I think  lies with  the chassis  support spigots on the bogies not being the same hight ,causing a lean to the left.This applies to both bogies. 

Inserting 0.5mm shims between the  support spigots and chassis gets all wheels  level.

Anyone tried running it down a gradient?

I have the flickering light as well.This is probably due to the varying load on the motor due to the issues within the geartrain (whatever they are).I have a tight spot in my example which is obvious at very low speed.As I have previously said I have fitted dummy wiper pickups to the drive bogie to smooth out any inconsistencies and this has greatly improved the performance.

As to your poor performance on the rollers I don't think bearing pickups are basically a good idea for obvious reasons.

Picked up my replacement today from RM and gave it about three hours circling using a Gaugemaster D controller. Considerably better runner than the original one. Not quite perfect but when I get the top off to switch off the lights I don't want I will check out the gears, pickups, etc. on the motor bogie. When I had it on the rollers with just the motor bogie end powered it did seem a bit sluggish, so I am wondering if the resistance through the pickups is varying the power to the motor as it runs.

The back to backs on the trailing bogie were a fraction tight but not enough to cause a problem on the track and they turned freely.

 

One thing I did notice was that there was a distinct flicker on the cab light at 30% power on the controller. There was no sign of it under about 20% and it had gone before 40%.

Any ideas what the reason could be?

Does that lead us to an answer or just pose another question?

OK, I officially give up. Whats the point of writing when nobody reads.

 

See post 544 on page 22.

 

Good luck, I'm out of here.

Some people may have just joined the topic and not have the stamina for the full story.

Swiftbeam says it won't propell itself on one axle.

It is only driven on one bogie

Received a replacement back this week,very same issues!I agree there is alot of slack in the gear train but this is not unusual in rtr.The friction free axle pickups are perhaps allowing the system to jiggle about.

I have fitted ad-hock pickups bearing on the flange tops of the power bogie wheels.Performance is now much better,though not perfect.I will adjust the pressure when I have time.

Simple, sloppy gears!

 

Mine now runs perfectly on a Black Beetle using Dapol electrics and Zimo decoder and power collected from the trailer. DC, DCC, makes no difference, all runs well through Dapol PCB and decoder. So you now also know it's nothing to do with PCB or the black coating on the wheel backs for the pickups (I've now hooked up the Black Beetle to collect power).

 

Electrics are not the problem here. How can they be when a Dapol PCB disconnected, PP3 battery to the rails and fitted Mashima motor STILL hunt?

 

 

Black Beetle can be bought, you just have to buy Direct from Steam Era Models. All sizes available.

Not just you Swiftbeam.

I thought that as I was doing my conversion.

So I did it just to see, don't bother.

Believe it or not, it can't generate enough traction to pull it's self, even on flat, straight, level track, I was shocked!

You could add lead in the space where the gears were and all around the bogie body.

Then you just end up with a single axle driven mess.

 

I think the drive is just a problem I had to be honest as everybody else don't seem to have a problem.

I've seen a few in shops this week and guys at the club were saying how good it is.

Don't worry abut the drive train, just run it, I'm sure yours will be spot on :-)

Glad to read you have your railcar running to your satisfaction although the solution is drastic. Your analysis of the issue seems very plausible. Perhaps the'hunting'is made worse by lack ofriction in the pickup system.Adding pickups to the wheelbacks may act as a damper to the differential backlash.

Why do other's seem to run ok!

I still await my replacement from Liverpool.

If you are a new reader to this thread, please read all pages going back to at least page 26 so you have a CLEAR understanding of what has already been tested. 

 

PLEASE NOTE ALL OF THE BELOW IS ONLY MY PERSONAL OPINION AND IS IN NO WAY TRYING TO CONTRADICT Dapol's DESIGN. I MAY JUST HAVE HAD THE ONLY THREE ENGINES IN THIS PRODUCTION BATCH THAT FALL BELOW MY PERSONAL STANDARD? ALSO I CAN IN NO WAY SAY WHAT WOULD HAVE BROUGHT THE TWO MODELS I SENT BACK TO THE SHOP UP TO MY PERSONAL EXPECTATION AS I NEVER LOOKED INTO THOSE MODELS.

 

OK Guys,

 

Here we have my final comment and conclusion of my personal Dapol Railcar in regards to its 'Hunting' issue I personally feel it had.

Hunting occurs at about 40% DC and 50% DCC, it is most noticeable on DCC, and this speed is exactly were most of us would perceive about 30mph to be in real life. This problem was present in all three of my Dapol Railcars. I have kept one and returned the other two as I only have the 'head space' to fix one problematic model.

 

When the model travels up hill, the hunting stops, when travelling down hill, the hunting stops, when against the buffer stops and wheels are slipping on the track the hunting stops. While hunting, you can hear the motor change revs or react to load change.

 

So a new Mashima 1628 motor was fitted and a new flywheel/drive cup was made. As some on this thread have already suggested may be the case, this motor change did nothing to solve the issue. So at this point all I have is the un-driven bogie collecting power, bigger wires fitted to this bogie and feeding the new motor directly. All that remained of the original Dapol System is the drive shaft, UJ and power bogie (not collecting power) and still the hunting persists. The UJ was ruled out as an Extra 0.007" shim was added to remove all traces of worm backlash. I think it is at this point safe to say my problem is in the driven bogie as there is simply nothing else left.

 

The problem was totally resolved by fitting a 26/12 Black Beetle bogie. This size is a tad short, but beggars can't be choosers when these power bogies are not made any more. 28/11.5mm is an exact match for the Dapol Railcar, but because you can't see the bogie, 2mm in length is not an issue. The difference in wheel size is also irrelevant because you have to 'make' the bogie fit, thus setting the ride height yourself. As I just stated, these bogies are no longer made, but some do still remain in stock if you hunt about. The other option would be a Tenshodo Spud , 'word on the street' is that these bogies are not the best, but I can't comment as I've never had one. There is also the Hornby or Bachmann option with something 'borrowed' from a DMU/EMU.

 

The model now runs without fault and is how I always wanted it to be. The up side is not only does the model run well, I've been able to remove the 'motor bulge'. The interior is in grey primer for now, but will be painted in the appropriate colours at a later date.

 

I am not a professor of engineering, so I can not 'tell' you why the problem with hunting is in my model, but I believe the issue lies within the gear train of the driven bogie. Excluding the worm and UJ's, there are 8 gears in total involved in taking the drive down from the worm to the wheels. In one of my wheels, I had 1/8th of a rev in free turn, and the other had only 1/16th of free turn. I don't know what that means in terms of drive, but the free rev in each wheel is not the same due to the uneven number of gears either side of the 1st driving cog from the worm. Over the 8 gears, there are 8 points of gear backlash. 

 

I think at low and high speed the bogie is pushing the body, but at mid speed, the backlash in the long drive train is having an influence. Maybe the gears push the body forward and the body takes up the backlash having been pushed by the gears, then coasts until it slows enough for the body to be pushed again by the gears? Maybe the weight of the body and the backlash in the gears is just enough to set off a harmonic oscillation when the drive train is at coasting speed.

 

I don't think the motor is being back driven by the bogie gears as the worm cannot be driven from the bogie side of the drive train. However, the fact that the motor is being affected during the hunting may be messing up whatever system is in play within the DCC system. I believe the DCC system uses some sort of feedback from the motor to control the speed, so a motor being forced to change its speed because of the drive train may explain why the hunting is more noticeable in DCC? Ironically, a flywheel will make hunting worse in this case as it is using its momentum to load the motor, and this is something else the DCC has to try and smooth out.

 

DC being a pure voltage, the controller is not trying to adjust for anything, the loco just reacts to the given voltage (assuming you are not using force feedback) So the hunting will show less.

 

If the above is correct, then very thick grease in the gearbox would help, or a much heavier body so the drive train is under load for longer, or some sort of brake giving resistance to the wheels. Unfortunately, all of these options will put the drive train under excessive load and cause damage. If my thoughts are correct, the model simply needs a better fitting set of bogie gears or a less convoluted or evenly spaced gear drive train.

 

AGAIN, MY PERSONAL THOUGHTS.

 

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No,there should foam pad on top of the motor which acts as a damper when the seating unit is refitted on top.My 122 had thiis missing and sounded like a herd of bees.Now added it runs very quietly.

Model railway magazine reviews exploded views show this pad eg Hornby July 2017

Good to hear this.Which type of gaugemaster,pure dc or feedback?

As mentioned in my previous post my railcar surges.Being pedantic this is not hunting but we are all talking about the same phenomenon. Having returned the railcar I await its replacement with interest.

That would assume it's the motor to blame and not the geartrain.

Sorry to read about your tribulations.Have the same problems myself.Sent the railcar back for replacement.I have tried it on three different dc controllers but still the same issues.

EDIT !!!!!!

 

If you read the post that was here, forget it !!!

 

I'm still getting the hunting, just at a lower speed !!!

 

I'm now giving up, I'm going to put it all back together as it was and get rid !!

 

Fedup  now!

 

I'll have no Railcars in the new few days, so I'm out of here.

 

Sorry