Giles Posted August 27, 2015 Share Posted August 27, 2015 Good Heavens! Very imaginative - and extremely well done. I love the concept of the built-up axle, and the fettling to get the mesh is brilliant. Ir knocks all my bodgery into a cocked hat!!! 1 Link to post Share on other sites More sharing options...
CME and Bottlewasher Posted August 27, 2015 Share Posted August 27, 2015 (edited) Otherplant, superb work! In the smaller scales too - wow! - dedication and inspiration - thanks for Posting. Edited August 27, 2015 by CME and Bottlewasher Link to post Share on other sites More sharing options...
otherplanet Posted August 27, 2015 Author Share Posted August 27, 2015 Thank you both for your positive feedback, its most appreciated. Giles I think there is a very thin line between filing something to fit and bodging. and I'm not sure any of us who have browsed you sites will accept very much self denigration on your behalf, they run too nicely. Hopefully the chassis will come together a little quicker. 1 Link to post Share on other sites More sharing options...
otherplanet Posted October 28, 2015 Author Share Posted October 28, 2015 The basic chassis is about done now. A piece of square section brass runs the length of the vehicle. I used the original plastic floorpan from the van and cut it into 3 sections, removing the locations of the axles. Then used this as a template to set the axle spacings. The rear axle is soldered to the longitudinal brass tube and is then sandwiched between the middle and rear sections The front is a little more complex. A small pivot bracket is soldered to the underside of the square brass, with a small length of steel wire passing through this and the front axle beam. This provides the simple compensation to cope with uneven roads. The floor pan is cut away much more here, to clear the swing of the wheels and the trackrods. conveniently the floor pan is quite detailed and the back end of the transmission case fits nicely over the pin. Then I discovered the motor stuck further through the floor pan than intended! Concequently I have added an extra gear ratio to step the speed up a little (it was calculating as being quite slow) but more significantly it allows the motor to sit higher. I still had to remove quite a lot of the floor pan to get everything in. but the motor fits behind what I presume is the fuel tank, that projects down from the floor. Nothing actually sticks out except a piece of plasticard that fits within the side cross section of the fuel tank. The motor sits in a cradle and is held in place by a clip that pivots over the top and holds everything down. You will note in the photos, this changes. the first version using steel wire was a) too stiff, b) not providing enough support. The motor and gear box have a very slight movement between them and the first clip didn't hold the gearbox end down well enough. The gears are very fine, mod 0.1. I suspect that this is too fine for the application as they have to be very precisely aligned. I shall have to see and if necessary change them for mod 0.2, but I shall aim to see if the ratio is right with the body fitted before I buy new gears. The servo mounts to the other side. There is a small cradle built from plasticard that surrounds and supports it around the main bearing. I had to remove one screw mount to prevent it intruding into the cab, but it appears sufficiently secure with just the one plus the cradle. I find the servo horns too long, so I cross drilled the spline and fitted one made from wire. This drives a link arm that snakes across under the floor to the opposite end of the track rod. I changed my original plan of attaching these and made a new trackrod end. (it needed extending anyway as the wheels were slightly toe out). the new end has two grooves cut in it, one for the steering link and one for the knuckle arm. In each case, the thin wire loop is crimped into the groove to make the joint captive. The result provides a reasonable equivilent to a ball jointed rod end, without too much free play. The two sections of track rod are joined with a piece of thin walled brass tube, this allows the tracking to be adjusted and then set with a drop of super glue. I had to see how things went. so I connected everything up to a test reciever and battery set that I have and drove figure of eights around the dining room table. The steering is excellent with a good turning circle, but the mod 0.1 gears kept coming out of mesh, hence the motor clip upgrade. I have yet to try the new version. The inside of the model has a second plastic moulding which provides the cab and the wheel arches. This has been hacked about and the rear wheel arches bonded directly to the floor pan, helping to strengthen the swiss cheese. the cab has also been hacked, with lots of clearance for the wheels to swing. However I have not fixed this down yet as the on-off switch is going into the engine cavity. With the body dropped back on, its almost impossible to see any of the modifications and a drop of black paint and some chemi blacking should hide them even further. Next is to add the battery cradle and receiver mounting. Then I can properly drive it around and test that gear meshing and speed ratios. 2 Link to post Share on other sites More sharing options...
CME and Bottlewasher Posted October 28, 2015 Share Posted October 28, 2015 The basic chassis is about done now. A piece of square section brass runs the length of the vehicle. I used the original plastic floorpan from the van and cut it into 3 sections, removing the locations of the axles. Then used this as a template to set the axle spacings. The rear axle is soldered to the longitudinal brass tube and is then sandwiched between the middle and rear sections chassis frame s.jpg The front is a little more complex. A small pivot bracket is soldered to the underside of the square brass, with a small length of steel wire passing through this and the front axle beam. This provides the simple compensation to cope with uneven roads. The floor pan is cut away much more here, to clear the swing of the wheels and the trackrods. conveniently the floor pan is quite detailed and the back end of the transmission case fits nicely over the pin. chassis assembly s.jpg Then I discovered the motor stuck further through the floor pan than intended! Concequently I have added an extra gear ratio to step the speed up a little (it was calculating as being quite slow) but more significantly it allows the motor to sit higher. I still had to remove quite a lot of the floor pan to get everything in. but the motor fits behind what I presume is the fuel tank, that projects down from the floor. Nothing actually sticks out except a piece of plasticard that fits within the side cross section of the fuel tank. floorpan s.jpg The motor sits in a cradle and is held in place by a clip that pivots over the top and holds everything down. You will note in the photos, this changes. the first version using steel wire was a) too stiff, B) not providing enough support. The motor and gear box have a very slight movement between them and the first clip didn't hold the gearbox end down well enough. motor side 1.jpg The gears are very fine, mod 0.1. I suspect that this is too fine for the application as they have to be very precisely aligned. I shall have to see and if necessary change them for mod 0.2, but I shall aim to see if the ratio is right with the body fitted before I buy new gears. The servo mounts to the other side. There is a small cradle built from plasticard that surrounds and supports it around the main bearing. I had to remove one screw mount to prevent it intruding into the cab, but it appears sufficiently secure with just the one plus the cradle. steering.jpg I find the servo horns too long, so I cross drilled the spline and fitted one made from wire. This drives a link arm that snakes across under the floor to the opposite end of the track rod. I changed my original plan of attaching these and made a new trackrod end. (it needed extending anyway as the wheels were slightly toe out). the new end has two grooves cut in it, one for the steering link and one for the knuckle arm. In each case, the thin wire loop is crimped into the groove to make the joint captive. The result provides a reasonable equivilent to a ball jointed rod end, without too much free play. The two sections of track rod are joined with a piece of thin walled brass tube, this allows the tracking to be adjusted and then set with a drop of super glue. I had to see how things went. so I connected everything up to a test reciever and battery set that I have and drove figure of eights around the dining room table. The steering is excellent with a good turning circle, but the mod 0.1 gears kept coming out of mesh, hence the motor clip upgrade. I have yet to try the new version. motor mount 2.jpg The inside of the model has a second plastic moulding which provides the cab and the wheel arches. This has been hacked about and the rear wheel arches bonded directly to the floor pan, helping to strengthen the swiss cheese. the cab has also been hacked, with lots of clearance for the wheels to swing. However I have not fixed this down yet as the on-off switch is going into the engine cavity. side view s.jpg With the body dropped back on, its almost impossible to see any of the modifications and a drop of black paint and some chemi blacking should hide them even further. Next is to add the battery cradle and receiver mounting. Then I can properly drive it around and test that gear meshing and speed ratios. Wow! Link to post Share on other sites More sharing options...
Giles Posted October 29, 2015 Share Posted October 29, 2015 (edited) Another Gem. I really like your technique for producing the rear axle/worm/gear housing. It's incredibly neat and effective - and very nice idea to build the chassis on a 'spine' in that way (more like a trailer). It's plenty to think about. (Edited for bl**dy auto-correct messing things up!) Edited October 29, 2015 by Giles Link to post Share on other sites More sharing options...
davetheroad Posted October 29, 2015 Share Posted October 29, 2015 Truly remarkable! Link to post Share on other sites More sharing options...
otherplanet Posted October 29, 2015 Author Share Posted October 29, 2015 Another Gem. I really like your technique for producing the rear axle/worm/gear housing. It's incredibly neat and effective - and very nice idea to build the chassis on a 'spine' in that way (more like a trailer). It's plenty to think about. (Edited for bl**dy auto-correct messing things up!) Thank you Giles, the spine adds a lot, providing sufficient strength without relying on the detailed floor pan. This meant that when the middle section of the floor broke away whilst cutting the clearance for the steering link arm, the basic structure remained. making it easy to fix. However soldering the rear axle square and central was tricky. I am wondering whether next time, I might divide the spine into two half lengths. Then use the glueing stage to achieve the alignment more easily. If i had realised earlier that i would need the spur gears, i would have made the square section that houses the worm taller and drilled it for the second shaft rather than relying on the gearmotor position and bearings to achieve the mesh. Link to post Share on other sites More sharing options...
otherplanet Posted March 25, 2016 Author Share Posted March 25, 2016 Well a bit more time has passed, and a lot more progress. The testing confirmed my suspicion about the 0.1 module gears. So I placed a big order from MikroAntriebe for some 0.2 module gears! The resulting tiny box, full of microscopic gears was a delight. One of the weaknesses of the previous generation was that the output shaft from the gear-motor was too floppy. It’s not really got the bearings for a radial load and the movement was more than the mesh of the old gears. So I extended the gearbox upwards to take a shaft and moved the gears to the other side from the motor. The new gears have a slightly lower ratio, reducing the overall van speed compared to the module 0.1 (they actually speed things up if you remember from above). With the new shaft all the radial loads go through the gearbox case. I used a short length of tube, cross drilled and pinned to the shaft and slotted to create a dog drive to the motor. The motor seat took a little fettling with scalpel and file and some new packing to match the new shaft alignment, but it wasn’t out by much. In the intervening period. I also ordered and received some very small slide switches. About 1.2mm thick surface mount devices, so one of these went through a hole in the chassis floor beneath the cab (which remains removable). I had couple of goes at wiring. The second got everything fitting in nicely. The original battery didn’t seem to fit properly. So I opted for a smaller unit, similar to that in the Atkinson. I glued one JST connector to the side of the servo for the battery and one to the floor behind the left rear wheel for charging. The power switch connects to the receiver when forward or to this 'charging port' when rearward. The Deltang receiver sits on a little mount behind the servo, the clips hold it in place but expose the critical solder pads so it can be wired in situ. With the help of my son we did a time trial. Time to complete a 1meter run. With a return run to repeat the timings (as is only right and proper). The conclusion was that the top speed is slightly over a scale 30miles per hour, which is a little more than I had aimed for. At least part of this is due to the discovery, during the rebuild, of some misalignment in the main axle shaft which was adding to the friction during earlier tests. The result is that the bottom speed is a little too fast. It can run slowly, but it is a bit tricky to keep it controlled that slow. There is however, plenty of torque, and despite the heavy body, it pulls well. If I were to build it again, I would do the intermediate spur gears with a 1:1 ratio and reduce the speed back to that of the original. I am however really pleased with the steering, the lock is good, with minimal slop and with a tight turning circle. I have attached a link below to a demonstration video. With the gubbins done. I painted the inside of the cab, adding a uniformed driver (I found a photo of a 1960’s BR delivery driver on the NRM online archive.) The main body and the glazing are completely unmodified for now. I originally planned to repaint the van including weathering and add front and rear lights, which the Deltang receiver is pre-equiped to control. However, as it stands, there are no exhibition bookings, I am also a bit bored of this vehicle project and champing at the bit to get on to my own layout project. So it will now pause at this state until I feel re-enthused, or an exhibition kicks me into finishing things off. To see it running go to: 6 2 Link to post Share on other sites More sharing options...
Robin2 Posted March 29, 2016 Share Posted March 29, 2016 I've just come across this now. Fabulous. I'm curious to know where you got the little gear and the worm for the back axle? Perhaps you made them yourself? ...R Link to post Share on other sites More sharing options...
otherplanet Posted March 30, 2016 Author Share Posted March 30, 2016 Hello Robin, Welcome to the thread & thanks for the positve feedback. No I didnt make them myself, I am good with a file and piercing saw, but not that good. I also have not used any machine tools more sophisticated than a dremel on these models. The gears came from the Mikro Antriebe site http://www.shop.kkpmo.com/ You can pick your choice of module, teeth number, bore dia, length and material. There is also a wide range of other components Alternately, I have also used Mikromodellbau http://www.mikromodellbau.de/Shop/index.php?sprache=2 They have a different cross section of products including compound gears Hope that helps. Geoff 1 Link to post Share on other sites More sharing options...
Robin2 Posted March 30, 2016 Share Posted March 30, 2016 Thanks for the links Geoff. I have bookmarked them. ...R Link to post Share on other sites More sharing options...
otherplanet Posted August 1, 2016 Author Share Posted August 1, 2016 Here is my first creation specifically for the new project. A pre WW1 B-Type Bus, built from the Keil Kraft kit. The ambition is to build a small Edwardian layout, inspired by the early Garden City movement, specifically the large building programmes which in at least some photos used tramways and later, railways to transport the building materials. The kit required some significant additional detailing. Including driver, conductor and passengers but I managed to keep the cabin free, with all the gubbins under the floor and bonnet. I have a couple more vehicles to build (at the boundaries of the max and min sizes etc). Before hopefully building the layout, which will take a long time with my record, as I will also need to keep building vehicles in order to maintain my own interest. So here is my question to the floor regarding the this my new topic. Should I: Hijack my own thread and just keep writing Start a new thread for the new layout and vehicles (leaving this for future 60’s vehicles) Combine a & b. carry on using this thread until I get the layout started and then start a new thread. Is he still rabbiting on about those trucks, doesn’t he know this is a model railway website. Something else. 2 Link to post Share on other sites More sharing options...
Giles Posted August 1, 2016 Share Posted August 1, 2016 I should carry on with this - at least we know where to find it!! Looking forward to it all! Link to post Share on other sites More sharing options...
RMweb Gold Corbs Posted November 1, 2016 RMweb Gold Share Posted November 1, 2016 (edited) Yes please do keep adding to this thread, inspirational stuff! Edited November 1, 2016 by Corbs Link to post Share on other sites More sharing options...
otherplanet Posted December 24, 2016 Author Share Posted December 24, 2016 A little teaser of the next project. 3 Link to post Share on other sites More sharing options...
Giles Posted December 24, 2016 Share Posted December 24, 2016 I really want to see this - but I confess, I can't make out much of what these parts are - unless the one on the left is a chassi block? Looking forward to whatever you're doing! Happy Christmas.... Link to post Share on other sites More sharing options...
Giles Posted December 24, 2016 Share Posted December 24, 2016 Forgive me reposting your video again.... It's well worth everyone seeing! 9 1 Link to post Share on other sites More sharing options...
otherplanet Posted January 4, 2017 Author Share Posted January 4, 2017 Re post away. your very kind. In fact you have reminded me that I have another video, mid editing, of the bus. I shall see if I can get it finished. You are quite correct on the teaser. 3D printed chassis block, still on its support structure. Sorry for the slight fuzziness of the image, I was in a bit of a rush and using the phone camera. Waiting on the gears to arrive from Poland so I can start trying to assemble it. 1 Link to post Share on other sites More sharing options...
otherplanet Posted January 15, 2017 Author Share Posted January 15, 2017 Well I've finally finished editing the bus video. About time too, I recorded it last February! I thought I would try something a little different back then. So recorded the main part of the build with a time lapse app on my phone. I had a weekend whilst my wife and children were away. I managed to get the basic vehicle completed and running, leaving only the detailing and painting still to do. Its still a bit longer than I would have liked, at over 11 minutes and not as perfect as I would have liked. But I think I have possibly spent as many hours editing it (in some places a frame at a time) as it took to do the build. So never again. Anyway I hope its of interest and perhaps will help to provide inspiration to a few more people to try this in the UK. 3 Link to post Share on other sites More sharing options...
davetheroad Posted January 15, 2017 Share Posted January 15, 2017 Brilliant and a tidy workshop as well! Link to post Share on other sites More sharing options...
CME and Bottlewasher Posted January 15, 2017 Share Posted January 15, 2017 Well I've finally finished editing the bus video. About time too, I recorded it last February! I thought I would try something a little different back then. So recorded the main part of the build with a time lapse app on my phone. I had a weekend whilst my wife and children were away. I managed to get the basic vehicle completed and running, leaving only the detailing and painting still to do. Its still a bit longer than I would have liked, at over 11 minutes and not as perfect as I would have liked. But I think I have possibly spent as many hours editing it (in some places a frame at a time) as it took to do the build. So never again. https://youtu.be/qgurmE57aAE Anyway I hope its of interest and perhaps will help to provide inspiration to a few more people to try this in the UK. Thanks for Posting the video, really informative and I, for one, appreciate the time and effort that you put in to it. Its surprising that making a video, photography, writing an article etc can take hours, but it is nice to share ideas and experiences. Link to post Share on other sites More sharing options...
otherplanet Posted January 15, 2017 Author Share Posted January 15, 2017 Brilliant and a tidy workshop as well! You wouldn't say that if you saw the workshop today! I'd struggle to put a business card down on a clear surface without tidying. But thank you. Link to post Share on other sites More sharing options...
Giles Posted January 16, 2017 Share Posted January 16, 2017 Lovely job- nice way of dealing with the servo in the wrong plane! Link to post Share on other sites More sharing options...
otherplanet Posted January 20, 2017 Author Share Posted January 20, 2017 Back to the teaser photo. Giles was right, it is a 3d printed chassis block. To assist in building the layout, I want a 'smallest' vehicle, to set the worst case road conditions. Much like using the shortest wheelbase 4 wheel loco and largest beheomoth loco that you want to run, to test the track quality and clearances. So this is my ambition. A Model T Ford, WW1 ambulance kit from RPM models. Officially, its 1:72 scale, but the wheel base is 33.5mm which scales out to the 100" standard of the Model T at 1:76, the track is a bit closer to the 1:72 Anyway, its close enough. Whilst the body is relatively large for a car based van, its still very small. In fact its smaller than any of the servos I have used in the past. So I am going to try hacking one smaller. Internally; it contains a bunch of gears, the motor, feedback pot and a very small PCB. Putting the gears to one side, that leaves these parts: So I have designed an insert to fit inside the back of the ambulance, Starting from under the drivers seat and extending back until just past the rear axle. This takes, a pair of 4mm motors for drive and steering, gears, and the servo pot. along with all the bearing mounts including the rear axle bearings. The new servo will have less torque than the original, but from experience, they provide much more than these little kits require. Whether this will all work is all an interesting risk, so I may have to completely redesign it and certainly expect to take several attempts to get things working. I printed it at work; where we have a Form 2 SLA printer and a CEO who is positively disappointed when engineers don't use the printers for home projects. This all fits approximately here. I haven't started hacking the kit yet. Just removed sufficient parts from the sprue to measure everything. I am also still waiting for the gears after I discovered that I had not completed the order properly. So I have had to delve into the spares box to get this far. To ensure the shafts run smoothly, I have inserted thin wall brass shells into the bearing holes. The tubing comes in telescopic sizes that are in 0.2mm increments. I.e. the 1.0mm fits inside the 1.2mm which fits inside the 1.4mm etc. Hopefully these will stay put in use. The RX, servo PCB, battery and charging socket will be scattered around the kit once I have more confidence in where the spaces are going to be I haven't decided whether to stick with the kit as supplied, and paint as a civilianised, ex war surplus truck or give it a new body and back date it to pre-war. I'll worry about that as and when I get it all working 5 Link to post Share on other sites More sharing options...
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