morairamike Posted September 22, 2012 Share Posted September 22, 2012 Bought an R373 Evening Star, old but in excellent condition. This has a ringfield 3 pole tender drive motor unit. My system is all DCC so thought I'd convert her to DCC. Ran OK on DC and so I did the change over. After the change I found that the loco would stall on Hornby diamond crossovers. Investigation revealed that the tender wheels are also one half of the power pickup/return. Further explanation. (Assume for ease of explanation that left is +ve and right is -ve). The five left hand wheels on the loco are the +ve pickup so there is lots of contact with the track. The -ve is the right side only on the tender. There are 3 wheels on each side, however the middle ones are very loosly fitted to allow radius 2 curves to be negotiated but they make poor contavt with the track. This leaves the front and rear wheels on the right side as the the contact for -ve. However on a diamond cross over the insulfrogs are exactly the same distance apart as the front and rear tender wheels and so contact is lost and the loco stops. FIX Looking at the loco it was established that the right hand loco wheels are electrically in contact with each other via the con roads and thus the valve gear. If a ohm meter is connected to a right side wheel zero ohms will be found at all points on the con rods and the valve gear. So the right hand loco wheels could be used for -ve. Disassembly of the 2-10-0 is easy and I soon had the loco stripped down. The expansion link/reach rod of the valve gear is held on the body chassis in a groove. I cleaned up the metal on the rear of the expansion link and soldered a thin wire to it. A small hole was drilled in the plastic chassis and the thin wire fed to the inside. This was run along the inside to the rear where I again drilled a small hole and fed the wire back to the outside. It was then routed to the top of the loco to tender link. Another small hole was drilled in the tender just above the tender to loco link pin. The wire was then fed through it. On the tender drive Evening Star the tender weights are held by screws to the tender chassis and are in electrical contact with it and thus the -ve. I drilled and tapped the forward weight and then after attaching a eye-end to the wire from the valve gear attached it to the weight with a small screw. The loco was reassembled and tested. Result no more stalling on diamond crossovers and a better runner. I used a stay alive decoder in this loco to further enhance its performance. However it did cure the diamond crossover problem on its own. Note that this modification at present means that the loco and tender can not be parted, but a small inline plug/skt will cure that if required. Link to comment Share on other sites More sharing options...
poliss Posted September 22, 2012 Share Posted September 22, 2012 That's a thorough job you've done there Mike. You should'nt have any problems with the loco stalling now. Will you be replacing the 3 pole armature with a 5 pole for smoother running? Link to comment Share on other sites More sharing options...
morairamike Posted September 24, 2012 Author Share Posted September 24, 2012 Ordered a 5 pole update from that well known sales site. Cheap. Link to comment Share on other sites More sharing options...
poliss Posted September 24, 2012 Share Posted September 24, 2012 Did you order the armature specially designed for the conversion as the standard 5 pole armature is a different size. Link to comment Share on other sites More sharing options...
2e0dtoeric Posted September 24, 2012 Share Posted September 24, 2012 Thanks for that description, Mike. I have two DC 9F's sitting on a dead track (disguised as my scrapyard), awaiting conversion to DCC at some point. One I may not bother with, because it keeps throwing the motor pinion gear off the shaft, for some reason. (I've tried locktite, superglue, and brute force, so far!) Link to comment Share on other sites More sharing options...
walkingthedog Posted September 24, 2012 Share Posted September 24, 2012 When I read your reply 2e0 I thought what a strange layout you had. DC9F is a freight version of the DC9 airliner. Then I switched my brain on and realised what you meant. Must be the rain!! Link to comment Share on other sites More sharing options...
2e0dtoeric Posted September 25, 2012 Share Posted September 25, 2012 walkingthedog said: When I read your reply 2e0 I thought what a strange layout you had. DC9F is a freight version of the DC9 airliner. Then I switched my brain on and realised what you meant. Must be the rain!! haha! You've heard of ships with trains on, now you've got steam airfreight! Link to comment Share on other sites More sharing options...
morairamike Posted October 1, 2012 Author Share Posted October 1, 2012 Ok back again. The armature arrived a week ago and I have been away so haven't had a chance to check it. Yes it's a direct replacement for the original 3 pole, the shaft being the same diameter. Next I changed the 3 pole armature over for the new 5 pole one. The most difficult part of the task was removing the motor unit from the tender chassis. The armature comes with a new drive cog and the old one has to come off to get the armature out of the motor case. In the end I removed the brush holder and then supported the motor housing so that the old armature was not impeded and then tapped the shaft out of the cog. Was unable to get a puller under the cog. Once off the change over went well. Reassembled and tested. Loco still requires the SV to be set to 20 on 128 steps but it runs with no sign of jerkyness. As warned in the fleabay instruction the motor ran backwards so I changed CV29 by 1, obviously the windings are reversed on the new armature. All in all the cost of £9.89 was well spent. Total time to change over and test 1:45. Link to comment Share on other sites More sharing options...
Fishmanoz Posted October 1, 2012 Share Posted October 1, 2012 Great description morairamike, the last bit is just what I needed too as I'm about to do one of those 3-5 poles conversions myself. I think I got my 5 pole from the same supplier as you, given you mention the instructions he provides. Mine is going in a diesel though, not a tender drive. As a matter of interest, what decoder did you use? I'm not sure if the R8249 will handle the current from this motor for a start. Link to comment Share on other sites More sharing options...
morairamike Posted October 2, 2012 Author Share Posted October 2, 2012 I went for a S2SAP from the stable of D** *on*epts (stars are c) which i got from that well known Hornby dealers Ha!!ons (! = T)from the spiritual birthplace of Hornby. Very quick delivery less than 24 hours. Excuse word mangling that way the post will be allowed. Link to comment Share on other sites More sharing options...
Fishmanoz Posted October 2, 2012 Share Posted October 2, 2012 Thanks, thought it might have been given the Stay Alive. Richard is a local supplier to me, only being 4,000km away on the other side of the country. Local postage is not much less than Hatton's RM Small Packets though. Link to comment Share on other sites More sharing options...
poliss Posted October 2, 2012 Share Posted October 2, 2012 I'd use the ones you find in glasses. Link to comment Share on other sites More sharing options...
Fishmanoz Posted October 2, 2012 Share Posted October 2, 2012 What do false teeth have to do with it? Link to comment Share on other sites More sharing options...
poliss Posted October 2, 2012 Share Posted October 2, 2012 For stripping the wires of course. What do you get if take all the false teeth in the world to Boston? A Massachusetts. Link to comment Share on other sites More sharing options...
Technician Posted October 11, 2012 Share Posted October 11, 2012 [reply]2e0dtoeric said: The loctite you need for that is 638 it is green and quite thick. clean the shaft and gear inner and put a SMALL spot on the shaft then slide gear and rotate it a turn or two. Then leave it it should go off in a few minuits but has been known to take an hour. I use it at work for putting gears on 4.5mm dia shafts with motors producing 150W and they dont come off. To remove them just heat to 180 Deg C and they will just fall off. Link to comment Share on other sites More sharing options...
Technician Posted October 11, 2012 Share Posted October 11, 2012 PS if its got superglue on it dont get it hot as it can give off a nasty gas. Link to comment Share on other sites More sharing options...
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