Oxford Rail announces - OO gauge GWR Dean Goods

[john dew]

Hi Keith

 

I fear I have the same problem......any ideas on how to remedy it? I dont want to send it back yet again.

 

Regards

 

John

[melmerby]

Hi Keith

 

I fear I have the same problem......any ideas on how to remedy it? I dont want to send it back yet again.

 

Regards

 

John

Hi John

I was wondering, if asked nicely, Oxford might just send out some replacement gear sets as that seems to be the problem.

Saves them the expense of replacing the complete loco.

I also don't really want to get mine replaced at the retailer as the chances of another dud are quite high.

 

I had a Bachmann pannier that was just the same and I traced that to some superfluous plastic on the idler gear.

Once removed it performed (as all my other panniers do) superbly.

 

Keith

 

EDIT

As I now have two identical locos, one good one not so, I suppose I could try swapping gears to see exactly which one is to blame.

Edited September 29, 2018 by melmerby

[john dew]

Keith

 

I had an identical situation with a pannier and , like you, I was able to fix it because all the gear wheels were accessible.

 

I may be mistaken but I wasnt able to strip the Dean down that far

 

 

My first Dean, a reliveried BR version, runs very well but I fitted it with a surplus TCS stay alive chip......I dont know whether the capacitor power is sufficient to overcome the hesitation at that one point in the cycle? The second Dean hesitates and then stalls at slow speeds.

 

John

[melmerby]

Keith

 

I had an identical situation with a pannier and , like you, I was able to fix it because all the gear wheels were accessible.

 

I may be mistaken but I wasnt able to strip the Dean down that far

 

 

My first Dean, a reliveried BR version, runs very well but I fitted it with a surplus TCS stay alive chip......I dont know whether the capacitor power is sufficient to overcome the hesitation at that one point in the cycle? The second Dean hesitates and then stalls at slow speeds.

 

John

Hi John.

My first Dean has a Lenz Standard + V2 installed and works OK

 

The second one seemed to be OK on DC but did need a little more voltage to get it going than I expected (I use a Bench PSU for DC checks).

I then ran it in at various voltages forwards and backwards for several hours. It seemed to be quite smooth but still needed a bit too much voltage to get it moving.

I fitted a Lenz decoder and that's when I found the problem.

Due to the PWM output of a decoder the loco would now start at a low speed but exhibits this sticking part way around each wheel revolution where it slows down.

Once moving at a reasonable speed you wouldn't notice anything was wrong.

 

This is in complete contrast to a Bachmann Collett Goods I purchased a couple of weeks back and also fitted a Lenz decoder to. I can get the wheels to turn as slow as tens of seconds per revolution due to the very smooth mechanism.

 

P.S. Has anybody stripped a DG down completely to get the gears out?

 

Keith

Edited September 30, 2018 by melmerby

[john dew]

I tried and failed on the Replacement Dean where the motor failed.The motor comes out ok giving more access to the worm and one gear wheel. The wheel set comes off easily so one can check the driving axle gear wheel. However I couldnt find a way of removing the complete gear/worm assembly......I guess I will have to try again on this one.

 

However, off topic, I have finally got around to attempting the “Melmerby mod” on the Fleischmann Turntable bridge.....thats todays task........will let you knowhow I get on

 

Cheers

 

John

[melmerby]

I tried and failed on the Replacement Dean where the motor failed.The motor comes out ok giving more access to the worm and one gear wheel. The wheel set comes off easily so one can check the driving axle gear wheel. However I couldnt find a way of removing the complete gear/worm assembly......I guess I will have to try again on this one.

 

However, off topic, I have finally got around to attempting the “Melmerby mod” on the Fleischmann Turntable bridge.....thats todays task........will let you knowhow I get on

 

Cheers

 

John

Hi John

 

The Gearset has a plastic cover on the RH LH side.

Once you have removed the wheels it just flips off revealing the two plastic gears.

 

IMHO the loco is quite well engineered. The driving wheels have separate bearings as does the worm. However the intermediate gear wheels just run on die cast stubs.

 

Having fully dismantled mine I cannot see anything obviously wrong so more investigation is needed.

 

Keith

 

EDIT Cover is on LH side!

Edited September 30, 2018 by melmerby

[melmerby]

Hi again John

 

I think I have cracked it

I tried the loco without either the side cover or the clip holding the worm in place and it ran from a much much lower speed. I had the loco wheels turning steadily at 1.5vDC across the motor.

Putting the side cover back slowed it down needing an increase in voltage to bring it back, clipping the worm cover back on needed a considerable increase before the mtor would start.

There are two lugs on the gear cover that locate the bearings, I reduced the height of these very slightly, that allowed the motor to turn at a lower voltage but still higher than without the side cover.

The cover has some circular ring mouldings, presumably to control the sideways movement of the gears so I again took a little off these (just a smidgen!)

The loco was back to running smoothly with just 1.5v across the motor.

I partly re-assembled it so the decoder was now in circuit and tried it on the rolling road. What a difference, before modding it was jerky but after almost perfectly smooth and at a lower start voltage.

 

So onto the layout fully re-assembled.

Using TrainController to do a speed profile the threshold voltage was now 37, it was 85(?).

Top speed with the same decoder settings was 88mph, previously it was <70, so there must be much less friction.

It is still slightly jerky but not as bad as it was so I'm getting there.

 

BTW if you are going to remove the side cover watch that you don't break off the plastic pin - I did!

 

Keith

Edited September 30, 2018 by melmerby

[BWsTrains]

Hi again John

 

I think I have cracked it

I tried the loco without either the side cover or the clip holding the worm in place and it ran from a much much lower speed. I had the loco wheels turning steadily at 1.5vDC across the motor.

Putting the side cover back slowed it down needing an increase in voltage to bring it back, clipping the worm cover back on needed a considerable increase before the mtor would start.

There are two lugs on the gear cover that locate the bearings, I reduced the height of these very slightly, that allowed the motor to turn at a lower voltage but still higher than without the side cover.

The cover has some circular ring mouldings, presumably to control the sideways movement of the gears so I again took a little off these (just a smidgen!)

The loco was back to running smoothly with just 1.5v across the motor.

I partly re-assembled it so the decoder was now in circuit and tried it on the rolling road. What a difference, before modding it was jerky but after almost perfectly smooth and at a lower start voltage.

 

So onto the layout fully re-assembled.

Using TrainController to do a speed profile the threshold voltage was now 37, it was 85(?).

Top speed with the same decoder settings was 88mph, previously it was <70, so there must be much less friction.

It is still slightly jerky but not as bad as it was so I'm getting there.

 

BTW if you are going to remove the side cover watch that you don't break off the plastic pin - I did!

 

Keith

Hi Keith,

 

That sounds most promising, any chance of a photo or two to guide the less gifted (i.e. me) thru some heart surgery.. Mine runs pretty well but still not 100% smooth all the time.

 

Colin

[john dew]

Hi Keith,

 

That sounds most promising, any chance of a photo or two to guide the less gifted (i.e. me) thru some heart surgery.. Mine runs pretty well but still not 100% smooth all the time.

 

Colin

Yes please!

 

John

[melmerby]

Yes please!

 

John

Don't expect miracles.

I have managed to improve the performance somewhat but it is still slightly jerky a very slow speed.

I have been playing more and found that some of the loco wipers were not touching the wheels, re-setting them has actually worsened the problem slightly and slowed the loco a bit at low speeds

As reported earlier in the thread it seems the later fitted motor is a bit weak.(Thinking aloud:  I wonder if a Mashima 1024 (or similar) might fit? )

I have a few pictures of the dismantled loco but they are not comprehensive. I don't want to strip it down again, getting the keeper plate with the wipers back on was a PITA, they kept getting stuck in the wheel spokes.

 

Keith

[john dew]

Don't expect miracles.

I have managed to improve the performance somewhat but it is still slightly jerky a very slow speed.

I have been playing more and found that some of the loco wipers were not touching the wheels, re-setting them has actually worsened the problem slightly and slowed the loco a bit at low speeds

As reported earlier in the thread it seems the later fitted motor is a bit weak.(Thinking aloud:  I wonder if a Mashima 1024 (or similar) might fit? )

I have a few pictures of the dismantled loco but they are not comprehensive. I don't want to strip it down again, getting the keeper plate with the wipers back on was a PITA, they kept getting stuck in the wheel spokes.

 

Keith

 

Hi Keith

 

No worries.....I dont blame you not wanting to refit the keeper plate again. I had exactly the same problem with wipers getting between the wheel spokes. A right pain.

 

Your description of the process is very clear. I will have a go when I get home from a short road trip. I take it there was no flash on the gear wheels but the mod to the gear cover lugs and the side cover mouldings did result in a significant improvement.

 

I will let you know how I get on

 

Cheers

 

John

[BWsTrains]

Don't expect miracles.

I have managed to improve the performance somewhat but it is still slightly jerky a very slow speed.

I have been playing more and found that some of the loco wipers were not touching the wheels, re-setting them has actually worsened the problem slightly and slowed the loco a bit at low speeds

As reported earlier in the thread it seems the later fitted motor is a bit weak.(Thinking aloud:  I wonder if a Mashima 1024 (or similar) might fit? )

I have a few pictures of the dismantled loco but they are not comprehensive. I don't want to strip it down again, getting the keeper plate with the wipers back on was a PITA, they kept getting stuck in the wheel spokes.

 

Keith

Hi Keith,

 

If you can post best of the photos you have that would be appreciated.

 

Regards,

 

Colin

[melmerby]

Here's what I have.

 

 

First a video of the defrocked loco on the rolling road

You can see the "stiction" at about 5 o'clock on the wheel revolution

It doesn't look too bad but was far more obvious running on the track, especially at low speeds:

 

 

Then I stripped it down.

 

Chassis:

 

The wheels:

 

The gears:

 

Unfortunately I didn't take any pictures of the platic bits!

 

I cleaned and oiled the gears and it made no difference.

Then I noticed that with the cover for the worm unclipped (the black plastic thing with a boss on top) the loco would run slightly faster.

This suggested that the gearset was too tightly meshed so I removed a very small amount of plastic from the little lugs that locate the bearings for the worm.

It did improve the running somewhat. I also noticed that the side cover, if not pushed fully home did the same, so again a very small amount of plastic was fileded from the thrust face.

That seemed to do the trick and the stutter in wheel rotation was now hardly noticeable.

 

I re-assembled the loco and tried it on the track.

At first I couldn't get it to run properly at all but that was because I couldn't get the wipers to make a decent contact on the back of the driving wheels

Eventually after 4 or 5 (or was it 6 or more?) attempts, I finally managed to get decent contact with the wipers.

Those wipers really are a PITA, I eventually resorted to thin slivers of plastic behind the wheels as I re-fitted the keeper plate with the wipers, so they couldn't catch in the wheel spokes.

 

Now the loco runs like this:

 

 

 

 

I think you will agree it doesn't run too bad now.

 

Keith

Edited October 4, 2018 by melmerby

[BWsTrains]

Hi Keith,

 

many thanks for pics and videos, the end result is a shade better than mine now. Does it come to a smooth stop? that was the week spot in my operation as it would occasionally stop dead, perhaps at the sticking spot in the rotation.

 

Colin

[melmerby]

Hi Keith,

 

many thanks for pics and videos, the end result is a shade better than mine now. Does it come to a smooth stop? that was the week spot in my operation as it would occasionally stop dead, perhaps at the sticking spot in the rotation.

 

Colin

A little bit suddenly but I have the starting voltage set to 1 in the decoder and that is what it is running at, which is normally OK but seems a bit high for the Dean.

I'll try it at 0 and see how it performs.

I'm actually quite impressed with the engineering with proper bearings for the axles and worm gear, which seems to have been let down by sloppy manufacturing and just mazak bearings* for the intermediate gears.

It is also a nice smooth motor but possibly a bit underpowered.

 

 

Keith

 

EDIT

*Why not hard steel shafts pressed into the casting?

Edited October 4, 2018 by melmerby

[Garethp8873]

Ian Allan today had a few of the Great Western livery Dean Goods' for sale today at £60 if anyone is interested...

[melmerby]

Ian Allan today had a few of the Great Western livery Dean Goods' for sale today at £60 if anyone is interested...

That's been in the Bargain Hunters Mk2

 

That was me and I purchased one which is what my recent posts refer to.

My first Dean actually ran reasonably well to start with

 

keith

[BWsTrains]

Ian Allan today had a few of the Great Western livery Dean Goods' for sale today at £60 if anyone is interested...

This raises a concern I've had since the 2 vs 1 flywheel issue was first alerted. There's nothing to stop the less scrupulous from swapping chassis between the two releases,on-selling the downgraded 2309 and getting an improved 2475.

 

I'm sure no one on here would do such a thing but it raises a worry when buying pre-owned from an individual on line rather than retailer where you have the consumer protection as a backstop.

 

Just thought I'd say.

 

Colin

 

Edit: to clarify that I'm not referring to Ian Allan's latest offering that you advised

Edited October 5, 2018 by BWsTrains

[melmerby]

I've reduced the start voltage CV in the decoder to zero and tried again.

The loco stops and starts at the lowest setting on the throttle but I notice that occupancy is also going on and off (I'm using TrainController) so all my tweaking of the wipers has still not resulted in reliable contact.

 

Here is the loco "running on the spot" so to speak and seems pretty good to me, just need reliable contact.

 

 

Maybe some more weight?

 

Keith

[cctransuk]

I've reduced the start voltage CV in the decoder to zero and tried again.

The loco stops and starts at the lowest setting on the throttle but I notice that occupancy is also going on and off (I'm using TrainController) so all my tweaking of the wipers has still not resulted in reliable contact.

 

Here is the loco "running on the spot" so to speak and seems pretty good to me, just need reliable contact.

 

 

Maybe some more weight?

 

Keith

 

I would not have thought that running a loco when it is pushing against an immoveable object would do either the motor or the gearing much good.

 

Not something that I would knowingly try!

 

Regards,

John Isherwood.

[melmerby]

I would not have thought that running a loco when it is pushing against an immoveable object would do either the motor or the gearing much good.

 

Not something that I would knowingly try!

 

Regards,

John Isherwood.

The loco is so light on it's feet that it does it very easily.

Most of my other locos would push that box down the track.

That is with a very low throttle setting

 

keith

[SDJR7F88]

ROD version was on display on the Oxford Rail stand at the Swansea Model Railway Exhibition. This livery rally does suit the Class well, especially alongside the new RailGun too!

ROD version was on display on the Oxford Rail stand at the Swansea Model Railway Exhibition. This livery rally does suit the Class well, especially alongside the new RailGun too!

[PanzerJohn]

Keith

 

I had an identical situation with a pannier and , like you, I was able to fix it because all the gear wheels were accessible.

 

I may be mistaken but I wasnt able to strip the Dean down that far

 

 

My first Dean, a reliveried BR version, runs very well but I fitted it with a surplus TCS stay alive chip......I dont know whether the capacitor power is sufficient to overcome the hesitation at that one point in the cycle? The second Dean hesitates and then stalls at slow speeds.

 

John

The second Dean hesitates and then stalls at slow speeds.

 

That's what mine was doing.

[melmerby]

The second Dean hesitates and then stalls at slow speeds.

 

That's what mine was doing.

So does did mine. (It is still slightly jerky at very low speeds, about a scale 5mph).

I noticed that when it stopped it was not drawing any current but after another tweak of the contact wipers I have managed to get it to keep moving.

 

As the jerk happens at exactly the same spot on the wheel rotation it must be something to do with the gear on the driven axle. It cannot be elsewhere as the other gears are rotating at a higher speed.

I wonder whether the gear is slightly eccentric? Due to the close meshing of the gears there is little room for error.

 

Keith

[brian777999]

I thought that the first batch of Oxford Deans were the problem and that they had now improved things at the factory. Is this conclusion correct or are there still some issues ?

Edited October 7, 2018 by brian777999