Robin2 Posted July 15, 2018 Author Share Posted July 15, 2018 I suspect these 3D printed gears might be a reaction to this. Yes, that makes sense - I had not thought of that as I have been working with the motors without the gearbox as I don't have space for it. ...R Link to post Share on other sites More sharing options...
Dazzler Fan Posted July 15, 2018 Share Posted July 15, 2018 (edited) Hi ! As stated above, current offerings do not meet the need. - these are bespoke for the purpose and affordable as a simple solution. The current eBay item is # 123215503408(Relisted on trip with more than 10 sold !) Of course these are designed for N20's with the square brass gearboxesThe N20 are high reving and 12v geared down to 60 rpm gives excellent torque for small OO locos.On the 0-4-2 SDJR 25a the assembly leaves the Cab free for detail. Noel Edited July 16, 2018 by Dazzler Fan Link to post Share on other sites More sharing options...
Robin2 Posted July 16, 2018 Author Share Posted July 16, 2018 On the 0-4-2 SDJR 25a the assembly leaves the Cab free for detail. But where would I put the battery and the wireless receiver and control electronics ? ...R Link to post Share on other sites More sharing options...
stewartingram Posted July 16, 2018 Share Posted July 16, 2018 But where would I put the battery and the wireless receiver and control electronics ? ...R In the bin? Stewart 1 Link to post Share on other sites More sharing options...
Robin2 Posted July 16, 2018 Author Share Posted July 16, 2018 In the bin? Stewart Luddite ...R 1 Link to post Share on other sites More sharing options...
AndyID Posted July 16, 2018 Share Posted July 16, 2018 In the bin? Stewart Nooooooooo! Send them here. Link to post Share on other sites More sharing options...
Nicktoix Posted July 19, 2018 Share Posted July 19, 2018 Hi ! As stated above, current offerings do not meet the need. - these are bespoke for the purpose and affordable as a simple solution. The current eBay item is # 123215503408 (Relisted on trip with more than 10 sold !) Of course these are designed for N20's with the square brass gearboxes The N20 are high reving and 12v geared down to 60 rpm gives excellent torque for small OO locos. On the 0-4-2 SDJR 25a the assembly leaves the Cab free for detail. Noel Thanks Link to post Share on other sites More sharing options...
DCB Posted July 24, 2018 Share Posted July 24, 2018 One of the variants fitted into a Hornby tender drive black 5. Yet to be tested under power as the araldite has been setting. Using bevel gears would probably have been the better option space wise as I had to do a lot of carving with a rotary burr. Won't get chance to fit pick ups until next week so will have to wait and see how it performs. Wondering what gear ratio the gearbox is. 6ft drivers give about 300 revs per mile or 300 rpm at 60 mph so if that is a 300 rpm motor gearbox plus a 2:1 ratio crown wheel you are looking at 30 MPH with the motor screaming its head off. My L&Y Pug chassis with an N20 uses Romford 60:1 gears and 14mm wheels and that seems to rev its head off but has more than enough torque to not notice whether the admittedly very light loco is running light or slipping to a stand overloaded. Link to post Share on other sites More sharing options...
RMweb Gold Regularity Posted December 5, 2019 RMweb Gold Share Posted December 5, 2019 On 15/07/2018 at 04:12, Dazzler Fan said: Hi ! On eBay.co.uk there are Shapeways 3D HP-Nylon bevel gears bespoke for these N20 motors sold as 2 pairs. Axle Gear is a force fit on a 1/8" axle and has glue lines; the motor gear fits the flat of the motor shaft. I searched for those, but sadly they are only available in the "lower 48" in the USA. Anyone know of any other options? Link to post Share on other sites More sharing options...
Stanley Melrose Posted December 5, 2019 Share Posted December 5, 2019 You could always search "plastic bevel gears" on eBay and find, for example, <https://www.ebay.co.uk/itm/20pcs-Plastic-Bevel-Gear-Right-Angle-Drive-Plastic-Gears-16T-Hole-2mm-Toy-DIY/321720574377?epid=601138800&hash=item4ae80a61a9:g:7~MAAOSwam1atMC9> HTH, Stan Link to post Share on other sites More sharing options...
Ruston Posted December 8, 2019 Share Posted December 8, 2019 On 05/12/2019 at 14:43, Regularity said: I searched for those, but sadly they are only available in the "lower 48" in the USA. Anyone know of any other options? I wouldn't be buying expensive things from Shapeways when you can get them from China for pennies, as suggested by the poster above. I've never used the bevel gears and prefer to use a pinion and crown wheel. By making a carrier for the crown wheel you can fix it to the axle by use of a screw, which allows the motor drive to be disengaged whilst fettling the rods etc. The pinion gears have a D-shape in them so are a simple push fit on the gearbox output - no messing about with glues. Link to post Share on other sites More sharing options...
drduncan Posted December 8, 2019 Share Posted December 8, 2019 57 minutes ago, Ruston said: I wouldn't be buying expensive things from Shapeways when you can get them from China for pennies, as suggested by the poster above. I've never used the bevel gears and prefer to use a pinion and crown wheel. By making a carrier for the crown wheel you can fix it to the axle by use of a screw, which allows the motor drive to be disengaged whilst fettling the rods etc. The pinion gears have a D-shape in them so are a simple push fit on the gearbox output - no messing about with glues. Ruston, From whom do you get the crown and pinion sets? drduncan Link to post Share on other sites More sharing options...
Ruston Posted December 8, 2019 Share Posted December 8, 2019 7 minutes ago, drduncan said: Ruston, From whom do you get the crown and pinion sets? drduncan They aren't sets as such. They are cheap Chinese nylon gears that are on ebay, from loads of different selllers. As long as you use the same 0.5mm module gears you can pick whatever diameter and number of teeth you want to suit your requirements. Link to post Share on other sites More sharing options...
RMweb Gold tomparryharry Posted January 14, 2020 RMweb Gold Share Posted January 14, 2020 Hello Folks. As usual, I'm late to the party... I have some questions about these little N20 motors. They look exquisite, and the gearbox faceplate looks as though it's capable of mounting either a Romford/Markits gear arrangement, or High Level. If that is the case, what size of screw thread are we looking for? M1.4, etc? I'm currently working with a standard 12v DC arrangement. All information will of course, be gratefully received. Cheers, Ian. Link to post Share on other sites More sharing options...
RMweb Gold chris p bacon Posted January 14, 2020 RMweb Gold Share Posted January 14, 2020 Which ones do you mean Ian ? I use this type with a gearbox https://www.ebay.co.uk/itm/DC-12V-300RPM-Mini-Metal-Gear-Motor-Model-with-Gearwheel-N20-3mm-Shaft-Dia-UK/323966003210?epid=939823511&_trkparms=ispr%3D1&hash=item4b6de0e80a:g:tfcAAOSwThNdu8v-&enc=AQAEAAACQBPxNw%2BVj6nta7CKEs3N0qVtPmKEwMzTM3Khf816xyynwt0Puflfhp3QQnO8AiCQTh8qZV%2FsZz2u0X2mO1SszPbfWPn4ZaYeZS4zCfw4TSkY50y%2B4uGl98pC5jpO%2BY1y9SND1EBkyRWoNyGzqtuIbD2A8oZoQZcCQLnMCmh7vw0lgF%2BaRfBsSbdb1XswXswgf9WyFbY1NrO3nbFtLD%2FIsDEgqLNSWPe3IrR57MVJVQT9wETmZQhsX5Qy6tRuK0hmCL2FpdrMTXXU6sbrfP3sEm7gfyaRdT0dR1J50TbZ0uFxwKLfQZ%2Bk57llAxFEgpK9%2FJjXhEzHsOBIB4Hsj7COxCHrWPjGEqam1iiGHWun72ttJHQfODxcWuPm9aLStVc5myhIJX8mOkr1mYXyFuNlaMHjVFzY4dAdi3YwqUztbdPBmE3vxQ6lHsryqu15T9oR1bVgnhph%2BCTUjNcPpeL8%2FjXNb3BGXeOdAcbn2UMB4r%2BG9GPPbIQL0nfwjNVVW4pt9tGMWPp8KJ6hjYdM8vt6Wsnoy8cqBC1ecGQOPSPq9OFaoVgmeUZ%2Bio5zaFq9YnO1YeKADTH4Gw%2ByAtsO8XVNUB92uzRvlsshS0KPoqzvpNkXvNq1J9%2ByHc9zbK0qZfgE6GlAB6qcEZGfKNgQzhlbpnfpgqE35gg2qP6tjMb3ewlH%2FICLBwdiPK8zNcHL1FHKcOAtFUIM1AUvgOSqUShAlZmCau%2FNlGuvWILxgkXege0RnHEDWiqKjlOeRvLhf%2F5dFA%3D%3D&checksum=3239660032105197e60d9a924a95974e090e884479c0&enc=AQAEAAACQBPxNw%2BVj6nta7CKEs3N0qVtPmKEwMzTM3Khf816xyynwt0Puflfhp3QQnO8AiCQTh8qZV%2FsZz2u0X2mO1SszPbfWPn4ZaYeZS4zCfw4TSkY50y%2B4uGl98pC5jpO%2BY1y9SND1EBkyRWoNyGzqtuIbD2A8oZoQZcCQLnMCmh7vw0lgF%2BaRfBsSbdb1XswXswgf9WyFbY1NrO3nbFtLD%2FIsDEgqLNSWPe3IrR57MVJVQT9wETmZQhsX5Qy6tRuK0hmCL2FpdrMTXXU6sbrfP3sEm7gfyaRdT0dR1J50TbZ0uFxwKLfQZ%2Bk57llAxFEgpK9%2FJjXhEzHsOBIB4Hsj7COxCHrWPjGEqam1iiGHWun72ttJHQfODxcWuPm9aLStVc5myhIJX8mOkr1mYXyFuNlaMHjVFzY4dAdi3YwqUztbdPBmE3vxQ6lHsryqu15T9oR1bVgnhph%2BCTUjNcPpeL8%2FjXNb3BGXeOdAcbn2UMB4r%2BG9GPPbIQL0nfwjNVVW4pt9tGMWPp8KJ6hjYdM8vt6Wsnoy8cqBC1ecGQOPSPq9OFaoVgmeUZ%2Bio5zaFq9YnO1YeKADTH4Gw%2ByAtsO8XVNUB92uzRvlsshS0KPoqzvpNkXvNq1J9%2ByHc9zbK0qZfgE6GlAB6qcEZGfKNgQzhlbpnfpgqE35gg2qP6tjMb3ewlH%2FICLBwdiPK8zNcHL1FHKcOAtFUIM1AUvgOSqUShAlZmCau%2FNlGuvWILxgkXege0RnHEDWiqKjlOeRvLhf%2F5dFA%3D%3D&checksum=3239660032105197e60d9a924a95974e090e884479c0 And use these gears to transfer drive to the axle https://www.ebay.co.uk/itm/20pcs-Plastic-Bevel-Gear-Right-Angle-Drive-Plastic-Gears-16T-Hole-2mm-Toy-DIY/161667623061?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649 I do have to ream the hole for the axle and gear shaft. So far I've only used them in small locomotives and railcars which aren't expected to do a lot of work. 1 Link to post Share on other sites More sharing options...
RMweb Gold tomparryharry Posted January 14, 2020 RMweb Gold Share Posted January 14, 2020 Hello Dave, you are right on the target. Nice one. I also bought 2 of these little motors. From what I can see, there are 2 small, tapped holes, above & below the 'D' output shaft. To my feeble mind, the gearbox faceplate is just right to accept a fold-up gearbox. In that way, I can use the normal Romford reduction set. I'd envisage something in the range of 30-40:1 ratio. The tapped hole had me worried. Not having a tap to the correct size would mean a 'bodge'. Bodges are ok, but I'm concerned about messing up a gearbox with such a small motor. The worm will need to be bored out to accept the 3mm output shaft, but I'll do this on a lathe. Cheers, Ian. 1 Link to post Share on other sites More sharing options...
RMweb Premium Michael Edge Posted January 14, 2020 RMweb Premium Share Posted January 14, 2020 I've been experimenting with the n20 motor/gearbox in bigger and bigger locos. First was a 7mm Ruston 48DS, more than adequate in this tiny loco and well out of sight in the engine casing. Latest is a 7mm Hunslet 05, weighted up to 450g at the moment it can still spin the wheels quite easily. Both these are used at 1:1 from the attached gearbox, the Hunslet has the turned back configuration - this would be narrow enough to fit between the frames of an O gauge loco with a 1:1 spur gear drive. However the Hunslet frames are narrower than normal and this wasn't possible so it has a 1:1 chain drive instead. Next build may well have one of these fitted where the gearbox of the full size loco is, driving on the jackshaft axle. The power of these tiny motors is incredible, power consumption is small and they don't seem to get hot. More recently I acquired some n30 motors, these are longer but they bolt directly on to a High Level gearbox. I had one total failure but at 99p that's not too serious. 1 2 Link to post Share on other sites More sharing options...
RMweb Premium Michael Edge Posted January 14, 2020 RMweb Premium Share Posted January 14, 2020 I should add that putting a worm drive on the end of this superb little spur gearbox negates the whole point of using it - it works well because it doesn't have an inefficient worm drive. 2 Link to post Share on other sites More sharing options...
RMweb Gold tomparryharry Posted January 14, 2020 RMweb Gold Share Posted January 14, 2020 4 minutes ago, Michael Edge said: I should add that putting a worm drive on the end of this superb little spur gearbox negates the whole point of using it - it works well because it doesn't have an inefficient worm drive. Thanks Michael. I haven't gone down the route of bevel gears, I'm wondering how you'd mount the motor. I can certainly see some applications, however. Cheers, Ian. Link to post Share on other sites More sharing options...
PenrithBeacon Posted January 14, 2020 Share Posted January 14, 2020 There is also this thread I am currently in the process of developing an RC project using an N20 motor but I'm still faffing about with it. The N20 motors with the integral gearbox could be useful and you can select the voltage/output RPM to suit. They come in different drive shaft sizes but 3mm seems to be the most common, probably because this is the size used on RC cars. Also this mounting block is I think of value too as are bevel gears like this. You can cut off the lugs on the mounting blocks and glue them inside the frames as an alternative to the traditional worm and worm wheel gearbox. There's lots to choose from. Cheers 2 Link to post Share on other sites More sharing options...
RMweb Gold tomparryharry Posted January 14, 2020 RMweb Gold Share Posted January 14, 2020 Thanks for all of your input, folks. My original question is this:- What size of screw do I require to fit an N20 motor to a fold-up type gearbox, ala an High Level-type gearbox? Cheers, Ian. Link to post Share on other sites More sharing options...
RMweb Gold ianLMS Posted January 14, 2020 RMweb Gold Share Posted January 14, 2020 Quick question (and probably a very silly one) but when using the bevel gears with this set up, I assume you put one on the motor drive axle shaft and the same size bevel gear on the wheel axle. As there is no grub screw, do you just superglue it to the axle? 1 Link to post Share on other sites More sharing options...
PenrithBeacon Posted January 14, 2020 Share Posted January 14, 2020 Some have a grub screw others not 1 Link to post Share on other sites More sharing options...
Giles Posted January 14, 2020 Share Posted January 14, 2020 1 hour ago, ianLMS said: Quick question (and probably a very silly one) but when using the bevel gears with this set up, I assume you put one on the motor drive axle shaft and the same size bevel gear on the wheel axle. As there is no grub screw, do you just superglue it to the axle? I use 5 minute epoxy or Loctite 601. If gluing, apply the glue to the bore of the gear - NOT the shaft - that way you'll avoid getting glue in the gearbox. Michael E is absolutely right about the benefit of not using worms. They're only something like 25% efficient if you're lucky, whereas a bevel gear approaches 90%. I've been using some extremely small motors with planetary gearboxes, and they also prove immensely powerful, relatively. A motor 6 x 8 x 16 handling a white metal loco quite happily..... 1 1 Link to post Share on other sites More sharing options...
AndyID Posted January 14, 2020 Share Posted January 14, 2020 1 hour ago, Giles said: Michael E is absolutely right about the benefit of not using worms. They're only something like 25% efficient if you're lucky, whereas a bevel gear approaches 90%. Poor old worm gears getting maligned as usual When comparing gear-train efficiencies we need to compare apples with apples. There's not a lot of difference between a 40:1 worm set and a 40:1 train of spur gears. The total gear ratio has a major impact on the friction. Some people say you can't back-drive a worm which is simply not true. I have an ancient Tri-ang DMU which has the original two-start brass worms driving replacement nylon worm-gear axles (can't remember who sold them now) and it's quite easy to back drive the motor. The main reason is because the gear ratio is quite small. It might only be about 10:1 but I'd have to count the teeth to find out. Conversely if you make a 50:1 reduction from a train of spur gears it will resist back-driving because of the amount friction that a 50:1 ratio produces. Link to post Share on other sites More sharing options...
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