hayfield Posted May 13, 2015 Share Posted May 13, 2015 I have bought a second hand Airfix class 31 loco which seems to have very noisy gears. I have oiled them but it still sounds very grating. Either the 2 wheel sets need changing and or the worm gears on the motor, any ideas please Link to post Share on other sites More sharing options...
RMweb Gold Scottish Modeller Posted May 13, 2015 RMweb Gold Share Posted May 13, 2015 Hi John, Once they become noisy - that's it.... Usually it's a vibration of the motor faceplates and magnet which transmits to and is amplified by the wheel sets and interaction to the track. You could try tightening the screws that hold them together - but it's usually a short term fix that will need to be repeated. Thanks Link to post Share on other sites More sharing options...
YK 50A Posted May 13, 2015 Share Posted May 13, 2015 Hi, My son has one which belonged to me when I was a child, must be nearly 40 years old, it had a DCC chip hard-wired in about a year ago. It sounds much like what I imagine a Mirrlees engined Brush Type 2 to sound like, but without the expense of a sound decoder. I don't ever remember it being quiet and you certainly know when he's running the thing. But it keeps going, I think that's just how it is! Alun Link to post Share on other sites More sharing options...
bigherb Posted May 14, 2015 Share Posted May 14, 2015 Both mine made a racket when I bought them new in the 80's, they haven't got any quieter or noisier over the years. Link to post Share on other sites More sharing options...
34theletterbetweenB&D Posted May 14, 2015 Share Posted May 14, 2015 All the Airfix five pole open frame motors are a good design, based I believe on the MW005 motor once used frequently to replace the XO4 for upgraded performance. The materials used were good, but they were cheaply manufactured at a low standard of precision, which means slackly toleranced parts. If you happen to luck into one where shaft and bearing fit is optimal and the armature happens to be balanced, it can be very sweet running indeed and a close match to the best in can motors now supplied in most RTR. But most sounded like coffee grinders from date of purchase, and graunch on from there. They seem pretty indestructible and the magnets don't lose field strength (or they are not old enough for it to have happened yet!). The noise is worst on the motor bogie design, which is direct drive to axle, so all the vibration is immediately transmitted efficiently to the rails, and thus to the baseboard acting as a loudspeaker diaphragm. If as I did for outdoor running you make a twin bogie drive and put the metal wheels from the unpowered bogies onto the powered axles, it had about the same noise output as my Flymo lawnmower, which is going some for such a small piece of kit. It would pull the side out of a house though, even on a wet rail. The version for the steam locos (N2, 61xx) at least has a two stage gear train, providing a little isolation. Link to post Share on other sites More sharing options...
hayfield Posted May 14, 2015 Author Share Posted May 14, 2015 This is a real greating noise, thinking about it the wheels are not in bearings and I guess they may have work the plastic housing away a bit. I wanted a RTR test loco for hand built track so the noise is neither here of there Link to post Share on other sites More sharing options...
RMweb Gold Scottish Modeller Posted May 14, 2015 RMweb Gold Share Posted May 14, 2015 This is a real greating noise, thinking about it the wheels are not in bearings and I guess they may have work the plastic housing away a bit. I wanted a RTR test loco for hand built track so the noise is neither here of there Hi John, Have a go at striping the loco down - it's farily easy to do. Once you have it apart there are some things you can chek. 1 - The gears... Do they have any damage or wear? Do they have any build up of dirt or other debris in the teeth? 2 - The chassis.. Does it show signs of wear in the axle bearing arches? Does it show any sign of wear on the keeper plate? 3 - The armature/worm gears... Does it show any wear on the worms? Does it still have bearings? Also - Check out YouTube to see if there is any video guide for this one - I'm sure there was at one time. See attached Instruction sheet. Thanks Link to post Share on other sites More sharing options...
RMweb Premium Clive Mortimore Posted May 14, 2015 RMweb Premium Share Posted May 14, 2015 Hi John As others have mentioned, the Airfix Type 2 was, is and always will be a noisy .........(Chose your own non-RMweb word). I think I have about 12 to 15 of them at present and cannot recall one running quiet in both directions, I have some that do run quietly in one direction only. I have never investgated why they run noisily as they all run well and have very good haulage capacity. Is it strange what one modeller will acept and another will not. Link to post Share on other sites More sharing options...
hayfield Posted May 14, 2015 Author Share Posted May 14, 2015 Thanks for the instruction sheet, I managed to take it apart yesterday and only had a quick look and gave the gears a quick oil. Will take it apart again and have a better look now I have had all the advice and thought through the problem, initially just thought it was dry gears, but it sounds like a football rattle. Must also give the Mainline class 45 a clean and oil Clive thanks for the info, but this one is a real noisy thing. Link to post Share on other sites More sharing options...
RMweb Gold Scottish Modeller Posted May 14, 2015 RMweb Gold Share Posted May 14, 2015 Must also give the Mainline class 45 a clean and oil Hi John, If it's an original Mainline one... Completely pull apart the power bogie. There will be a fairly thick white/grey layer of grease - it gets darker as it ages and the motor is run. First - Remove it all - from everywhere! Then- Reassemble with only the smallest amount of oil on the bearing areas - include the armature ends where they show through the motor casing. Do not try to clean the commutator copper surfaces. Doing so will put tension on the fine wires to the motor windings and probably break them. This will mean the motor is ruined - it's a serious issue! Hope this helps! Thanks Link to post Share on other sites More sharing options...
RMweb Premium Clive Mortimore Posted May 14, 2015 RMweb Premium Share Posted May 14, 2015 Hi John If your 31 is very noisy check the motor mounting plate. If it is cracked or split, then it will be very very noisy and just about pull itself around . It is knackered if that is the case. Link to post Share on other sites More sharing options...
hayfield Posted May 15, 2015 Author Share Posted May 15, 2015 Thank you both for the replies, I will give the Mainline loco a quick service service and will follow the advice re the grease The Airfix loco's chassis/motor seems intact and not split, the motors armature seems to be sprung, so cannot be tested once the wheels are off. The gears look to be un-damaged, but the motor is a bit sluggish so I guess its very knackered. I guess its needs the motor bogie replacing, but is it work it as the centre wheel is a plastic dummy mounded on to the chassis, Is there a more recent replacement? Still only lost £11.50 and could be something I could repaint and or detail Link to post Share on other sites More sharing options...
34theletterbetweenB&D Posted May 15, 2015 Share Posted May 15, 2015 Here's what I do. Extract old chassis. Cut away screw posts inside body. Obtain very cheap Hornby class 30/31 chassis with ends mazak rotted off. Insert in Airfix body. (A couple of pieces of blu-tack neatly retains the body on the chassis if you want to make a 'professional' job of it.) Link to post Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.