Kernow Adams O2

[SRman]

See if you can lash up some sort of weight over the front, bluetak something on or,as in one of the preceding posts, rest something in the open smokebox. This at least should tell you if it is weight related.

 

I did put a little weight on the front to no effect. There are springs over the rear bogie but they seem to be control springs rather than suspension so aren't pushing the weight  forwards. The ccrew is very short but I tried loosening it slightly. Maybe stretching the springs will assist with the weight transfer a bit.   

 

 

 

I would check that the worm is not catching on the motor or supports in one direction.

 

Something like that has occurred to me but I haven't had the body off to check, yet. I wonder if the decoder wiring loom is catching. I'll pull the smokebox door off and ease the decoder out a bit and see if that makes a difference.

 

 

 And if it isn't a mechanical problem once BB's suggestion has been investigated.

I think that a sound analysis, so when:

 

 I would suggest that another possibility is the decoder frequently very briefly losing track supply due to either a momentary short or pick up failure; not for long enough that it shuts off and restarts, but enough that power to the motor sags off. I'd operate it in the dark to see if any sparking is evident as this often reveals the problem location.

 

 

I like that idea of looking in the dark. I remember the old Triang locomotives used to spark all the time - quite spectacular in the dark! I'll be giving that a try this evening.

 

 

 

Thanks all for the suggestions. They will keep me going for a while.

[JimHearne]

Okay I've trawled back through the thread but cannot find any comments re the strange plastic box in the accessory pack and the large flat piece. What are they? 

 

I'm glad it's not just me wondering that....

 

Jim

[SRman]

I have looked at the exploded diagrams. The flat piece I think you are referring to has two T-section ribs running down one side. It is shown as going somewhere to the rear of the cab, but where exactly is not clear. I suspect it may be a baffle to seal off the coal space for when sound is fitted. but that is only a guess.

The box like thing, I would guess, is a holder for a sugar cube speaker. There is mention of that in one of the magazine reviews.

I still haven't worked out where all the pipes go.

[Gwiwer]

The second O2 has arrived.  This is 30225 which is a mainland example not fitted with the push-pull gear.  It would have worked branch lines and probably shunted yards with no need of a turntable but would have had to run round at a terminus.  Back in its day many had suitable loops to do so.

 

DJ Models has ensured that the detail differences between individual locos have been captured in the models so aside from the glaringly obvious absence of Westinghouse pump there are tiny detail variations around the loco.

 

Of note also this loco does not feature the tank reinforcement as on 30182 and which can be seen in my photos above as a line along the lower part of the tanks.  

 

Once again I have added a Bachmann crew, suitable bits from the bag and lump coal.  The headcode disc is set for Exeter Central - Sidmouth Junction - Sidmouth or Plymouth Friary - Turnchapel.

 

Similar weathering has been applied though with a little smokebox washout residue on 30225 instead of tank filler rust as on 30182.  There's also a little white residue around the whistle on this one.

 

 

 

 

 

 

And to show how effective the coal can look when compared with the manufacturer's plastic moulding:

 

 

These tiny locos were never intended to haul long trains.  On my layout, which has steep gradients, they run well on their own but will grumble with two or three coaches on.  30225 "picked up her skirt" slightly when starting smokebox-first with a load on.  This is a railway term meaning the weight transfer shifts away from the driving wheels causing loss of traction and spinning. She's had some air-dry clay added to the smokebox void as ballast with good results.  She starts and runs better with a modest load and the clay being inert will not affect the electrics inside.

 

Making headway with the Maunsell set

 

 

 

And tackling a short parcel train with the driver giving the photographer a jaunty wave!

 

[SRman]

I have just tinkered a little more with my O2, concentrating on weight distribution. Incidentally, what I thought were springs on the rear bogie were, in fact, the electrical pickups.

I decided to add spacer for the bogie pivot, using a section of brass handrail wire. This gives a small amount of springiness, and if wound tightly around the chassis pivot, won't be in danger of shorting out the pickups on both sides. I experimented with a double wound spacer but that lifted too much weight off the rear driver, so a single circlet of brass is proving sufficient.

At the other end, I added a small rectangular section of lead, wrapped in insulation tape and glued lightly to the bottom of the smokebox interior.

Finally, I cleaned the wheels to ensure that any dirt built up from the imbalance was eliminated.

I reduced the parcels train by one van (a Parkside kit) and sent it around. There was a small amount of wheel slip in both forwards and reverse orientations, so I seem to have cured the problem at the expense of slightly reduced hauling power in reverse, but stronger performance facing forwards.

It will certainly now cope with two or three free-rolling coaches.

[Butler Henderson]

Re the Pressfix numbers I used, I have now used a ultra fine black permanent marker to dab on the visibly widest part and then wiped that all round the number using a Pantone by Letraset Fine Line creamy yellow 134 marker. Has toned down the 9s such that they appear weathered now in comparison to the rest. Have given up trying simply to change the 5 to a 9 on the smokebox number plate as no smokebox numbers I have match those on the model so it will be a complete renumber.

Edited November 12, 2015 by Butler Henderson

[Butler Henderson]

Managed to get 8g of lead in the smokebox along with a decoder, anyone know what is the optimal. Its noticeable how there is no comments from he who designed the model regarding this apparent need for more weight.

[ChrisG]

I have just tinkered a little more with my O2, concentrating on weight distribution. Incidentally, what I thought were springs on the rear bogie were, in fact, the electrical pickups.

 

I decided to add spacer for the bogie pivot, using a section of brass handrail wire. This gives a small amount of springiness, and if wound tightly around the chassis pivot, won't be in danger of shorting out the pickups on both sides. I experimented with a double wound spacer but that lifted too much weight off the rear driver, so a single circlet of brass is proving sufficient.

 

At the other end, I added a small rectangular section of lead, wrapped in insulation tape and glued lightly to the bottom of the smokebox interior.

 

Finally, I cleaned the wheels to ensure that any dirt built up from the imbalance was eliminated.

 

I reduced the parcels train by one van (a Parkside kit) and sent it around. There was a small amount of wheel slip in both forwards and reverse orientations, so I seem to have cured the problem at the expense of slightly reduced hauling power in reverse, but stronger performance facing forwards.

 

It will certainly now cope with two or three free-rolling coaches.

 

 

"Coping with two or three free-rolling coaches" after additional weight being added is not great to hear when you are an IOW modeller and you expect one to be able to haul 6 coaches loaded with holiday makers at speeds of up to 60mph.  I had three of the mainland versions running very happily and sweetly around my layout earlier in the week, though we didn't hang any rolling stock off the back so I can't comment on my experience of the haulage capacity.

 

Chris

[SRman]

To be fair, the Hornby Van Cs are not exactly free rolling, and my test train had one of those in the rake. The other items were the Parkside van I removed later, a CCT and two of Bachmann's new PMVs, plus the Bachmann BG. Overall a good test rake but probably not as free running a collection as , say, five or six free-running bogie coaches.

[ChrisG]

To be fair, the Hornby Van Cs are not exactly free rolling, and my test train had one of those in the rake. The other items were the Parkside van I removed later, a CCT and two of Bachmann's new PMVs, plus the Bachmann BG. Overall a good test rake but probably not as free running a collection as , say, five or six free-running bogie coaches.

 

That sounds more encouraging, though I do build my rolling stock to be fairly stiff: a) so that it doesn't roll away on an incline and b)  because I think the trains move more realistically (though that could just be rubbish!). I was staggered by how free-running the new Bachmann PMVs are, and how hilly my layout was revealed to be!

[Gwiwer]

And to be fair the Hornby push-pull and Maunsell sets I used are not 100% free-rolling either.  The O2s did better with Bachmann Mk1 stock.

[SRman]

That sounds more encouraging, though I do build my rolling stock to be fairly stiff: a) so that it doesn't roll away on an incline and B)  because I think the trains move more realistically (though that could just be rubbish!). I was staggered by how free-running the new Bachmann PMVs are, and how hilly my layout was revealed to be!

 Going slightly off-topic for a moment, a friend here in Melbourne has a near scale model of Exeter Central under his house. We test the rollability of stock by placing the item at the top of the 1 in 30 gradient and seeing how far they go. A GW autocoach (probably Airfix or Mainline - I can't remember which) rolls at high speed down the hill, through the back straight and two-thirds of the way around the return curve into the fiddle yard loops. A Wrenn SR CCT placed at the top of the gradient sits there, until given a nudge where it then rolls approximately 9 inches to a foot or so then grinds to a halt!

 

It would be interesting to try some of the previously mentioned stock to see how they fare in the rollability stakes!  

[Gwiwer]

Further testing has been carried out here.

 

30182 remains unmodified; 30225 has the clay ballast in its smokebox.  Today's test train was four Bachmann Mk1 TPO vehicles which roll very freely.

 

Running smokebox first 30182 successfully completes the circuit of the main layout with those four on at half power though slows noticeably on all climbs.  30225 slips slightly when lifting the load then runs well enough but more slowly and comes to a stop through low power when a gradient is met; increasing the power results in movement being restored but she slips to a stand on the steeper climbs.  Interesting given that this is the loco with extra front-end weight added.

 

Running bunker first 30182 performs identically while there is a slight improvement with 30225 but still slipping to a stand.  30225 has also been found to have the rear set of pony-truck wheels bind momentarily which may be either cause or effect.  I back off the truck fixing screw by a quarter-turn which seems to have rectified that but with only very marginal improvement in performance.

 

I tried each loco in turn on the steep branch with a single BG; 30182 lifted it easily to the top while 30225 refused to take it onto the gradient at all.  With a second BG added 30182 unsurprisingly slipped to a stand but only near the top and almost made it.

 

Given that the track and test conditions are the same for both locos and that 30225 now has a modest additional weight over the front drivers I am now more puzzled than ever as to why one loco runs better than the other.  Items yet to be checked include back-to-backs and pick-ups so either or could be part or all of the issue here.

[roundhouse]

Collecting mine for the sorting office this morning. Wont get chance to look at it til tonight and run it on 'Roundhouse' once set up at the Spalding show

 

EDIT - collected

Edited November 13, 2015 by roundhouse

[SRman]

I'm probably guilty of monopolising this topic a little, lately, but just to show that it's sorted nicely now, here's the O2, 30182, on a suitable Maunsell Pull-Push train Hornby coaches) with PMV (Bachmann) inserted in the set. The O2 had no problems with this light load and romped around the layout. The pics are chosen to illustrate various parts of the journey under its own power.








I'll try to keep quiet for a while here.

[PhilH]

 

....... I am now more puzzled than ever as to why one loco runs better than the other.

JLTRT then......

[Purley Oaks]

I'll try to keep quiet for a while here.

No please don't, the pics are great!

 

Hopefully Dave Jones will respond at some stage - but I still applaud him and Kernow for making such a wonderful model.

 

Magnahesion anyone?

 

Mal

[phil-b259]

Managed to get 8g of lead in the smokebox along with a decoder, anyone know what is the optimal. Its noticeable how there is no comments from he who designed the model regarding this apparent need for more weight.

 

Probably because there is nowhere else to add it. Please remember that the designers have needed to find space for a DCC decoder and a small speaker - both of which many people on here regard as essential.

 

If you don't have DCC then obviously the space for the chip can be filled with weights of some description, but that cannot be something a manufacturer can do from the outset.

 

I have two of these beauties (with another on the high seas) and as far as I can tell the designers have done the best they can as the choice of materials when it comes to trying to get weight where it is needed.

[34theletterbetweenB&D]

... Given that the track and test conditions are the same for both locos and that 30225 now has a modest additional weight over the front drivers I am now more puzzled than ever as to why one loco runs better than the other.  Items yet to be checked include back-to-backs and pick-ups so either or could be part or all of the issue here.

Difficult to test this type of loco with and without carrying wheels. Drag in this location is what I would be looking at.

 

Regarding 0-4-4T, I have just one, an M7 bought from a kind member here some years ago, (and still have to get around to remodelling it into Stirling GNR type). Now it was hopeless for traction as received, and the reason immediately obvious: the bogie wheels not turning to match rail speed. With the bogie wheel wipers backed off to barely grazing the wheelbacks, GT85 in the bogie bearings and graphite on the wheelbacks, this little charmer will now start and move at slow speed a 12 coach set of Bachmann mk1s. On the level only, mucho slipping even on slight (accidental) gradients at one or two locations. If it goes onto a 1 in 80 downhill section with that trainload there is no stopping until back on level track, runaway!

 

The stock all free rolling, my standard is 'gets away unassisted when placed on a true 1 in 100'. As observed above, free rolling stock does discover gradients on what is supposedly level track. I guess it is a matter of taste whether you like stock free rolling or not, but to me this is the 'secret essence' of the railway and I wouldn't have it any other way. RTR stock with dreadful inside bearings just doesn't make the cut; if good enough as a model it gets rebuilt for proper outside bearing pinpoint wheelsets, and then freely rolls away.

[Butler Henderson]

Probably because there is nowhere else to add it. Please remember that the designers have needed to find space for a DCC decoder and a small speaker - both of which many people on here regard as essential.

The loco is designed for the speaker going in the bunker and as I have got a decoder in the smokebox as well as the extra weight not having enough weight in the first place remains questionable.

Edited November 13, 2015 by Butler Henderson

[autocoach]

My pre-order for K2106 was shipped on Saturday (not arrived yet) and i only ordered it late last year. 

So they must be almost done.

Maybe your CC details are out of date, it has been mentioned that they leave any of those till the end,

 

Jim

Turned out to be the Credit Card. Almost all US credit cards have been replaced this past 6 months as we are finally catching up with the embedded chip technology. Unfortunately KMC web sales application does not have a way to update the card on an existing order.  I received an email from KMC today suggesting how I do it. 

 

Turns out best way is to make a new purchase and notify them to use this card on the old order. Now I will have the shipping wait of about 2-3 weeks for the little beauty to arrive.

 

I have a temporary non-sound DCC chip removed from a non-operating BWT (somehow the pickups have gone awry) to run in silence until an accurate sound of O2 arrives sometime next year.

Edited November 13, 2015 by autocoach

[51E]

Probably because there is nowhere else to add it. Please remember that the designers have needed to find space for a DCC decoder and a small speaker - both of which many people on here regard as essential.

 

 

Room for a DCC decoder yes but room for a small speaker I wouldn't say is essential.. Surely enough weight for it to run in the first place is more important? Not much point having sound but going no where?! 

[Ian Hargrave]

Room for a DCC decoder yes but room for a small speaker I wouldn't say is essential.. Surely enough weight for it to run in the first place is more important? Not much point having sound but going no where?! 

Is that really the conclusion that is implied in this thread....that insufficient adhesion results from its design ? Surely not.When the Isle Of Wight versions arrive,more grunt will be needed to haul a prototypical rake than the Maunsell sets seen here for sure.And is there a substantial difference between analogue and DCC.in haulage capability with the O2 ?

[Wheatley]

Is that really the conclusion that is implied in this thread....that insufficient adhesion results from its design ?

Yes. Too much plastic and not enough mazak. Other manufacturers are using mazak running plates and other components to get adhesive weight up, and have been for some time. Am I right in guessing that the O2 is mostly plastic apart from the chassis block ?

[Butler Henderson]

Room for a DCC decoder yes but room for a small speaker I wouldn't say is essential.. Surely enough weight for it to run in the first place is more important? Not much point having sound but going no where?! 

The loco design copes with sound okay in any case as the speaker would be in the bunker - the last place on a 0-4-4T you would want to add traction weight - the issue is how much weight should their be in the smokebox/ boiler - leaving it all clear for a 6 pin decoder is unnecessary as even a sound decoder will fit an area 4m high.