Astir648 Posted June 23, 2016 Share Posted June 23, 2016 Hi. I'm hoping someone can help with a little advice. My 7mm small space shunting layout Scotland Street (http://www.rmweb.co.uk/community/index.php?/topic/107026-scotland-street/) currently has two locomotives: an Ixion Fowler, which acts as an industrial shunter and a Heljan Class 20, whose role is to bring short trains onto the layout and maybe do a little shunting. In time they will be joined by a Class 08, either Dapol or my own MMP kit-built, whichever arrives first! My problem is the Heljan 20, which is awful at slow speed work. The Fowler trundles up and down at fabulously slow speeds and with excellent control. By comparison the Heljan hurtles around and shunting with it rather terrifying as the fine control simply isn't there! Ian Futers has two on his Lochty Road layout and when I saw him at the Scottish Exhibition Centre earlier this year he said he has the same problem. Lochty Road of course is a stabling point, so shunting is less of an issue and Ian is able to make do. So here's the question - will DCC solve the problem or is this just a case of "it's a big heavy monster of a loco with a huge flywheel and two motors so it's never going to be any good at slow speed stuff"? Does anyone have any experience of these locos with and without DCC? I'm currently using a Gaugemaster P controller - the 5 Amp version. Many thanks in advance! David Link to post Share on other sites More sharing options...
RMweb Gold MarshLane Posted June 23, 2016 RMweb Gold Share Posted June 23, 2016 Hi. I'm hoping someone can help with a little advice. My 7mm small space shunting layout Scotland Street (http://www.rmweb.co.uk/community/index.php?/topic/107026-scotland-street/) currently has two locomotives: an Ixion Fowler, which acts as an industrial shunter and a Heljan Class 20, whose role is to bring short trains onto the layout and maybe do a little shunting. In time they will be joined by a Class 08, either Dapol or my own MMP kit-built, whichever arrives first! My problem is the Heljan 20, which is awful at slow speed work. The Fowler trundles up and down at fabulously slow speeds and with excellent control. By comparison the Heljan hurtles around and shunting with it rather terrifying as the fine control simply isn't there! Ian Futers has two on his Lochty Road layout and when I saw him at the Scottish Exhibition Centre earlier this year he said he has the same problem. Lochty Road of course is a stabling point, so shunting is less of an issue and Ian is able to make do. So here's the question - will DCC solve the problem or is this just a case of "it's a big heavy monster of a loco with a huge flywheel and two motors so it's never going to be any good at slow speed stuff"? Does anyone have any experience of these locos with and without DCC? I'm currently using a Gaugemaster P controller - the 5 Amp version. Many thanks in advance! David Hi David, Im not an electronics expert, but i've always worked on the basis that DCC can only improve the handling of what is already good. If a loco runs awfully on DC, then chances are DCC won't really improve it. It does sound like something isn't right however, I have a pair of Heljan Class 20s, and they creep .. literally. I'm on DCC admittedly, but before chip fitment, when they were on DCC, i could get them to take 30 odd seconds to cover a metre-length of track! Has the loco had a running in - assuming you have the ability to do that on track? If not, i'd suggest finding a way, of making the loco secure, with power to the wheels, off the track, and allowing the motor to run slowly for 30 minutes or so to bed in. It certainly shouldn't 'hurtle around' on low power! Rich Link to post Share on other sites More sharing options...
3 link Posted June 23, 2016 Share Posted June 23, 2016 Hi David, I have a friends class 33 on my layout at present, I know it's not a class 20 but it's being run on DC and it is one of the most smooth and slow running diesels I have come across. Martyn. Link to post Share on other sites More sharing options...
F-UnitMad Posted June 24, 2016 Share Posted June 24, 2016 If you're still on 12vDC, re-wire the motors in series. That will help slow running enormously - did it with my HJ Hymek, & all my Atlas O American locos. If/when you go DCC, leave it wired in series, & you won't need massive 4Amp-plus decoders either. That saves a fair bit of money!! Series wiring will drop the top speed, but for a shunty-plank that's no issue at all. Link to post Share on other sites More sharing options...
Astir648 Posted June 24, 2016 Author Share Posted June 24, 2016 Thanks for the responses - definitely food for thought! I wonder if my loco might be faulty. At it's slowest speed, just above the stall (and not as slow as the Ixion Fowler) there is a slight jerkiness to it, which doesn't seem to fit with Rich and Martyn's experience. Time to take a screwdriver to it I think... David Link to post Share on other sites More sharing options...
Jintyman Posted June 24, 2016 Share Posted June 24, 2016 Thanks for the responses - definitely food for thought! I wonder if my loco might be faulty. At it's slowest speed, just above the stall (and not as slow as the Ixion Fowler) there is a slight jerkiness to it, which doesn't seem to fit with Rich and Martyn's experience. Time to take a screwdriver to it I think... David Hi David, Some Heljan models suffered from a cracked nylon gear in the gear train, check that all the gears are ok and if you find one cracked Howes do replacements. Hope you get it sorted. I've just had a Heljan Warship and it's super smooth straight out of the box. Jinty Link to post Share on other sites More sharing options...
deltic17 Posted June 24, 2016 Share Posted June 24, 2016 I had a Heljan 20 (since sold purely as it didn't really fit into my NE based layout) but it was a lovely smooth runner so it sounds as though something is not right with yours somewhere. Link to post Share on other sites More sharing options...
toffee Posted June 24, 2016 Share Posted June 24, 2016 I had a Heljan 20 (since sold purely as it didn't really fit into my NE based layout) but it was a lovely smooth runner so it sounds as though something is not right with yours somewhere. Not fit in ? Gateshead, Thornaby, York and Hull all had 20s in their early years ? Any later ? Make up your own rules that one was needed ! Link to post Share on other sites More sharing options...
John R Smith Posted June 25, 2016 Share Posted June 25, 2016 I have a pair of Heljan Class 20s, and they creep .. literally. I'm on DCC admittedly, but before chip fitment, when they were on DCC, i could get them to take 30 odd seconds to cover a metre-length of track! This struck me as a bit odd when I read it, so I have just checked - surely 30s to cover a metre is not really that slow. I have just timed my Bachmann 03 and it will take 450 seconds (7m 30s) to go from one end to the other of a Peco yard length of track. This is dead smooth with no hesitation - in fact it takes so long you can get really bored waiting for it. And of course, any speed above that is equally smooth. The little Dapol Terrier is pretty good, too, perhaps not quite as good at creeping but close. This is using my Minitrol DC controller which is now 35 years old. None of the Heljan products I have tried have been that good (a class 33 which was OK and 3 railbuses which I kept sending back because they were so poor). On a big layout slow-speed running is perhaps not quite so important, but on a small BLT or shunting plank it is vital to have perfect control just like the real thing. John Link to post Share on other sites More sharing options...
F-UnitMad Posted June 25, 2016 Share Posted June 25, 2016 I think it's possible to get a bit hung up about slow running times, possibly because we don't see much real shunting these days, & so forget it's purpose - to sort stock as quickly as safety will allow. What is more important to me than slow running itself is smooth stopping & starting, to & from a reasonable speed, which for real shunting would be around walking pace, at least when the Shunter is alongside the wagons ready to unhook the coupling (talking in British terms; US 'switching' is slightly different). Link to post Share on other sites More sharing options...
Astir648 Posted June 25, 2016 Author Share Posted June 25, 2016 Thanks for all the suggestions. I've opened up the gearboxes and happily there are no split gears (I asdume it would be fairly obvious?) but I found one of the wheel bearings was misaligned, which has helped a little. I tried running it over a measured yard and the slowest it will do reliably is 16 seconds. It will go slower but is liable to stall. I notice the tail lights flicker quite a bit at slow speed. The throttle needs to be opened up a bit before they become steady. Is this normal? David Link to post Share on other sites More sharing options...
John R Smith Posted June 26, 2016 Share Posted June 26, 2016 David Flickering lights on the Heljans I think is normal at very low DC speeds. On DCC I think they are always on full? (on a separate supply). Let's go back to the real thing. As said above, when you are working a yard or station with the human shunter on the ground the loco will be moving at about walking pace, say 3mph. In O Gauge that works out to 30 secs to cover one yard of track. But the loco should be capable of moving from zero up to that speed and braking down from it almost imperceptibly and smoothly, just like a full-size class 20 or whatever. And when you are buffering-up, then 3mph is rather too fast, unless you want some expletives from the guard and the rest of the crew. Which is not to say that a great deal of shunting was not in fact pretty brisk, when you just want to move stock from one place to another in the yard. But then the human shunter will be riding aboard or walking across tracks, not desperately trying to chase the train! The other point is that steam shunting and diesel shunting should look rather different. Diesels do tend to almost imperceptibly gain speed and slow down again, whereas it was usual for steam engines to open up quickly, give things a brisk shove, then coast gently to a halt over the rest of the distance. John Link to post Share on other sites More sharing options...
chaz Posted June 26, 2016 Share Posted June 26, 2016 Thanks for all the suggestions. I've opened up the gearboxes and happily there are no split gears (I asdume it would be fairly obvious?) but I found one of the wheel bearings was misaligned, which has helped a little. David, Your assumption is wrong - you could well have a split gear and it may not be at all obvious. I had such a fault in a Heljan 47 - and it took a while to find. Here's how to check. With the body off turn the chassis over and support it so that you can rotate the motor flywheels by hand. Deal with each bogie separately. Put a pen mark on the top of one gear tooth in the gear train before you start - that way you will know when you have made a complete turn! Turn the motor shaft a little at a time and check each gear in the train carefully as you go. If there is a lot of white grease on the gears you make have to remove this to be able to see. If you have got a split gear there will be a crack in the nylon in the bottom of the slot between two adjacent teeth. If there is one it will not seem very significant but it will allow that gear to expand a bit on its shaft - enough to bind with the adjacent gears. take your time checking and be very thorough! (As I said a split may not be obvious) Hope that's helpful. It took me quite a time to find the defective gear wheel in my 47, but replacing it transformed the performance. Chaz Link to post Share on other sites More sharing options...
deltic17 Posted June 27, 2016 Share Posted June 27, 2016 Not fit in ? Gateshead, Thornaby, York and Hull all had 20s in their early years ? Any later ? Make up your own rules that one was needed ! Thank you for your interest. I am modelling Gateshead (part of) in 1980 so plenty of Class 03's,08's,31's,37's,40's,45's,46's,47's & 55's. Class 20 were very rare visitors to GD at the time and if one or a pair did turn up they were normally dispatched back to where they had come from as soon as possible (normally York). They did appear a bit more as the 1980's progressed sometimes towing dead locos back to Gateshead from say York but once again they would return immediately to York. As you say I could make up my own rules but I am just trying to accurately portray a typical day in the North East in 1980. Link to post Share on other sites More sharing options...
Waveydavey Posted June 28, 2016 Share Posted June 28, 2016 Don't forget Thornaby had a large allocation of class 20s during the late 1980s and into the 90s. Mainly used on Boulby traffic and metals sector trains. Link to post Share on other sites More sharing options...
Astir648 Posted June 28, 2016 Author Share Posted June 28, 2016 David, Your assumption is wrong - you could well have a split gear and it may not be at all obvious. I had such a fault in a Heljan 47 - and it took a while to find. Here's how to check. With the body off turn the chassis over and support it so that you can rotate the motor flywheels by hand. Deal with each bogie separately. Put a pen mark on the top of one gear tooth in the gear train before you start - that way you will know when you have made a complete turn! Turn the motor shaft a little at a time and check each gear in the train carefully as you go. If there is a lot of white grease on the gears you make have to remove this to be able to see. If you have got a split gear there will be a crack in the nylon in the bottom of the slot between two adjacent teeth. If there is one it will not seem very significant but it will allow that gear to expand a bit on its shaft - enough to bind with the adjacent gears. take your time checking and be very thorough! (As I said a split may not be obvious) Hope that's helpful. It took me quite a time to find the defective gear wheel in my 47, but replacing it transformed the performance. Chaz Clearly I need to look more closely! Thanks Chaz - I'll follow your advice and see if that's where the problem lies. On a related subject, odes anyone know where I can lay my hands on replacement Heljan screw coupling parts? The outer part (sorry - not sure of the correct terms) of one of mine is missing in action. David Link to post Share on other sites More sharing options...
peter220950 Posted June 28, 2016 Share Posted June 28, 2016 Hi David, Howes are the spares provider for Heljan, currently out of stock, but keep an eye on the website: https://www.howesmodels.co.uk/category/'O'%20General%20spares Peter Link to post Share on other sites More sharing options...
John R Smith Posted June 29, 2016 Share Posted June 29, 2016 David Just an observation - I have noticed that both Heljan items I have owned (a class 33 and a Railbus) have been extremely sensitive to track dirt build-up. Even when the rails look perfectly clean my Railbus gets all jerky and difficult to control at very low speeds, but if I clean the rails with a little alcohol and cotton buds it results in a huge improvement. Whereas my Dapol Terrier is by no means so fussy. So it could well be worth cleaning the track, wheel treads and pickups really thoroughly before you go any further. John Link to post Share on other sites More sharing options...
Astir648 Posted July 1, 2016 Author Share Posted July 1, 2016 Thanks John - good point. I did give the wheels a good clean but the track could be due for it by now. David Link to post Share on other sites More sharing options...
robertc Posted July 1, 2016 Share Posted July 1, 2016 You obviously have two problems David. You haven't mentioned what you are using to control the loco....that might explain the speed issue. However if the controller used is not the problem, then you may have a motor fitted that is not the same as those from other posters. Perhaps the batch your loco comes from might have higher speed motors fitted. They might look the same externally. While DCC is not the panacea for dodgy pickup it can and is used to tune locos that run too fast. It is a simple matter to alter a couple of settings to set starting and top speed and make something that runs more akin to a slot car into a perfectly controllable loco. So if you are planning to move to DCC you will have that advantage, the series wiring suggested can be a good fix for either means of control. cheers Bob Link to post Share on other sites More sharing options...
Simond Posted July 2, 2016 Share Posted July 2, 2016 Re the coupling - would the end of a Premier Components coupling fit? They're tapped 12BA. Best Simon Link to post Share on other sites More sharing options...
Astir648 Posted July 9, 2016 Author Share Posted July 9, 2016 Re the coupling - would the end of a Premier Components coupling fit? They're tapped 12BA. Best Simon Hmmm. Not sure what thread the Heljan one is but, it's worth a try - thanks Simon. Link to post Share on other sites More sharing options...
Astir648 Posted July 9, 2016 Author Share Posted July 9, 2016 You obviously have two problems David. You haven't mentioned what you are using to control the loco....that might explain the speed issue. However if the controller used is not the problem, then you may have a motor fitted that is not the same as those from other posters. Perhaps the batch your loco comes from might have higher speed motors fitted. They might look the same externally. While DCC is not the panacea for dodgy pickup it can and is used to tune locos that run too fast. It is a simple matter to alter a couple of settings to set starting and top speed and make something that runs more akin to a slot car into a perfectly controllable loco. So if you are planning to move to DCC you will have that advantage, the series wiring suggested can be a good fix for either means of control. cheers Bob Thanks Bob. I'm using a Gaugemaste P - the O Gauge version (PO?). DCC is definitely on the cards for the future, but I want to focus on scenics and rolling stock first. David Link to post Share on other sites More sharing options...
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