stu357 Posted February 23, 2017 Share Posted February 23, 2017 I've been messing about with some old Lima models recently. I know what's said, but I cant help it, look at my thread on railroad 08s! I have had various ideas about re-wheeling some 73s, not for true scale looks but to get rid of the traction tyres and add pick ups. I've got plenty of Hornby 12.6mm coach wheels lying around and thought they would be a good cheap starting point. I think they are approaching the diameter of real 73 wheels? I've read some threads speculating what you could do without going to the expense of Ultrascale so I thought I'd have a go. Here's the starting point, I cut some brass tube, that was slightly oversized in diameter to the axle, to the width of the bogie, then filed an area out of the lower part to locate it with the base plate (not really necessary but it looked neater) I then squashed the ends to fit in the Lima slot in the bogie.This gives an oval end which does not allow any twist but gives a little compensation between the wheel sets . I filed the point off the axles so they didn't foul the bogie frame. they fit quite neatly and already spin much more freely than the original wheels. Next job was to cut some new pickups from thin brass, you have to do both sides as the Hornby wheels are insulated both sides. I drilled small holes in each one so that I could melt it into the plastic with a soldering iron. Here it is all assembled. just replacing the trailing bogie with this has massively improved the slow running with no other mods. I have a video of it running noisily, but slowly. If I can upload it I'll get it on. I had ideas about using these wheels on the drive bogie and have had a go on a Lima 33 using 14mm wheels and turning down the original axle wit a Dremel and file. One in 3 tries It worked but took so long to get them true, I have ideas for this one using the wheels designed for the new can motored Hornby version. Stu Link to post Share on other sites More sharing options...
stu357 Posted February 23, 2017 Author Share Posted February 23, 2017 Here's the video of it running, More to test adding a link to a video than anything! https://youtu.be/9rHqcxasAPc Stu Link to post Share on other sites More sharing options...
SRman Posted February 23, 2017 Share Posted February 23, 2017 The extra pickups and decent wheels that don't tarnish every time you even glance their way make a huge difference. Link to post Share on other sites More sharing options...
Ray M Posted February 23, 2017 Share Posted February 23, 2017 Feel free to have a go, at one of the old Heljan class 47`s please. with all wheel pick up. Link to post Share on other sites More sharing options...
muddy water Posted February 23, 2017 Share Posted February 23, 2017 Great idea! What size brass tube did you use? I have some lima class 47 bogies to re wheel with Hornby 14.1mm coach wheels. Link to post Share on other sites More sharing options...
Andrew F Posted February 23, 2017 Share Posted February 23, 2017 Nice work. What will you do with the power bogie and wheels? The gears are of course on the wheels rather than the axles and other than Ultrascale wheels I can't think of a fix for these older motors. Link to post Share on other sites More sharing options...
John Tomlinson Posted February 23, 2017 Share Posted February 23, 2017 I have tried to remove gears from lima wheels before to attempt a rewheel of a 33 I had 25 years ago and completely goosed up the attempt because I should have pushed the wheel inserts out of the metal tyres to access the plastic properly in order to safely cut it with a hacksaw. So I would guess that if the plastic centres can be pushed out enough to get at the plastic behind the gears then with very careful cutting it should be possible to remove them from the original wheels. Then once the gears are removed they can be tidied up and glued to the back of the replacement wheels before they are fitted to the axles but only after the glue has cured. That would be how I would do it but anyway hope this helps. Brian Kirby has demontrated this with Hornby wheels on his "Swindon & Derby" dmu thread. Another option is presumably to turn down the flanges on the Lima wheels, if not with a lathe then one at a time perhaps using a Dremel type drill and a file. In respect of post #4, concerning old Heljan wheels, after repeated cleaning to remove the factory applied blackening, these will remain clean, it just takes a bit of effort to go back and try again when you thought you cracked it and hadn't! John. Link to post Share on other sites More sharing options...
stu357 Posted February 23, 2017 Author Share Posted February 23, 2017 Great idea! What size brass tube did you use? I have some lima class 47 bogies to re wheel with Hornby 14.1mm coach wheels. I used this, Hope that helps, Stu. Link to post Share on other sites More sharing options...
stu357 Posted February 23, 2017 Author Share Posted February 23, 2017 It took me a while to work out how easy it is to get the drive cog off the lima wheels, Just cut it off, I thought they were moulded or bonded to the wheel, but they are not. If the hole in the plastic cog isn't damaged and the new axle is an identical size to the old, they centre up really easily and you just two part epoxy onto the back of the new wheel. I learned a lot from my lima 33s, this one uses the 14mm Hornby wheels on the original Lima axle. I haven't got a lathe yet, when I get use of one this is a viable way of doing it. I actually used a dremel and file like this, this is a failed attempt, left side isn't square! eventually ended up with this, this was the first attempt at pickups with .4 nickel silver. they work but they are hard to get adjusted and can squeal or squeak. that's why I've moved to brass sheet. Id bought some Heljan sprues for steps etc so had ended up with almost complete Heljan bogies. I utilised these as trailing bogies, but again with Hornby 14mm wheels and on this one the same style pick ups, So, onto the second Lima 33, I was a bit impatient to get hauling mk1 coaches with this one, to do all the work on the Hornby wheels, but wanted rid of the traction tyre, I used the original trailing wheels I had spare and glued the cog onto the back of them. I also had the idea of swapping sides with the insulated wheel so I didn't need a pickup on the cogged side. trailing bogie was again a cut down Heljan one but with better pickup arrangement , If all my drive wheels had been nice polished ones I'd be happy to leave this like it is, but the front set are the old brass ones and pick up dirt everywhere. I'll re do this at a later date..... Link to post Share on other sites More sharing options...
stu357 Posted February 23, 2017 Author Share Posted February 23, 2017 BTW, you can turn the traction tyre retaining flange down with the power of a Lima motor! as a test I used a Stanley knife blade as a kind of scraper rather than a file just to see if it would work before I removed the old wheels.. DONT use the motor and drive bogie that you eventually want to use as 9 times out of 10 something jams and you damage a cog or armature, but if you have a spare power bogie you can keep it as a mini lathe! Link to post Share on other sites More sharing options...
stu357 Posted February 24, 2017 Author Share Posted February 24, 2017 Back to the 73 bogie, I cut the cog off the old wheelset, then pulled off the drive wheel and removed the cog from the axle. I bought some new Hornby trailing wheels (from "Peters Spares") and carefully removed the insulated one, I install the cog on the back of the non insulated side ( I moved the pickup wire to the other side of the motor.) I carefully re assembled the axle sets. (actually they are pretty easy to get square on these ones) I did have to remove a small boss from the back of the drive wheel to get the cog to sit flat against the back of the wheel. I will add a pickup to the non drive side next, then do another running quality video! Stu. Link to post Share on other sites More sharing options...
stu357 Posted February 24, 2017 Author Share Posted February 24, 2017 Here's the chassis on another slow run with new drive wheels.(extra pickup on the non drive side of the power bogie fitted) much better and passes the points without stopping. https://youtu.be/3cu-10g-SkA I need to find a CD drive motor next! Link to post Share on other sites More sharing options...
stu357 Posted February 25, 2017 Author Share Posted February 25, 2017 Just found this pic of the wheels with the traction tyre retaining lip turned off using a spare motor and file. Before I swapped the drive wheels, definitively improved running but again brass wheels get dirty quickly. Link to post Share on other sites More sharing options...
stu357 Posted February 27, 2017 Author Share Posted February 27, 2017 So here is the extra pick up for the non drive side, and fitted, Link to post Share on other sites More sharing options...
stu357 Posted February 27, 2017 Author Share Posted February 27, 2017 Now I have 2 73's that run really slowly over fairly dodgy track. I was feeling like Id accomplished something until i looked at it side on! I know I'm using slightly different size wheels either end but I wasn't expecting it to look that bad. so I had to move the wheels up in the trailing bogie, I filed out the slots that my brass tube sits in by .5mm and removed the boss from the top of that bogie to reduce the gap, then on the power bogie i removed the bosses where the screws go in and cut the bogie frame so it sat inside the motor side frames instead of under it, then did the usual trick to lower a Lima and filed down the pads that the chassis sits on. next to paint the front face of the wheels black to disguise them, although if I have it apart again I might try to spin the Hornby 73 wheels in the Dremel and see if I can use a file to make them look more like the others. Link to post Share on other sites More sharing options...
stu357 Posted March 4, 2017 Author Share Posted March 4, 2017 On to the motors, I've been collecting CD drive motors for a while, most are 5.9 volts, but you sometimes find 12v versions. (scrounge old CD drives and PCs, you'd be surprised how many people have this stuff in the loft!!) I used the 2 12v ones I had on the 33s that i did so had been hoping to find some more. That did,t happen so I decided to use some of the 5.9v ones up and see how I get on. I don't bother with any fancy locator or mounting bracket, just the screws that you sometimes find the CD motor mounted to the circuit board with (not always) an old motor case serves as a jig which I line up by eye, In the past I have used the Scalextric cogs but it turns out you don't need to, Just cut the Lima one off, Use some of this heat shrink, Shrink down with a soldering iron, leave a little extra length which shrinks smaller and allows the cog to go on easier. Put the lima cog on and trim off the excess. then screw into the housing, I did use spots of superglue to locate it and then did up the screw. this works well on the later (screw on drive wheels) type bogies and you can even use a screw top and bottom. the ones with the clip on drive wheels need the screw hole about 2 o'clock and make sure it wont catch on the other cogs. That seems to have been a success, It makes the best improvement for quietness and smoothness and wont stop me from using the lower voltage motors. OK, being 5.9V they will go at warp speed and that's when they would potentially overheat. At normal operating speeds they never get warm, you just have to be gentle to turn the controller as you depart. they also now run at the same speed and can successfully double head on DC Both these bogies had the cogs tidied up and that made them quieter, but it seems most of the Lima noise was coming from uneven commutators as they went much quieter with the motor swap. Link to post Share on other sites More sharing options...
stu357 Posted March 4, 2017 Author Share Posted March 4, 2017 And here's another video with the motors in (bodies and detailing still a work in progress.) https://youtu.be/J6mTI4Cf8A8 Stu. Link to post Share on other sites More sharing options...
tractor_37260 Posted March 4, 2017 Share Posted March 4, 2017 It took me a while to work out how easy it is to get the drive cog off the lima wheels, Just cut it off, I thought they were moulded or bonded to the wheel, but they are not. If the hole in the plastic cog isn't damaged and the new axle is an identical size to the old, they centre up really easily and you just two part epoxy onto the back of the new wheel. I learned a lot from my lima 33s, this one uses the 14mm Hornby wheels on the original Lima axle. I haven't got a lathe yet, when I get use of one this is a viable way of doing it. I actually used a dremel and file like this, this is a failed attempt, left side isn't square! eventually ended up with this, this was the first attempt at pickups with .4 nickel silver. they work but they are hard to get adjusted and can squeal or squeak. that's why I've moved to brass sheet. Id bought some Heljan sprues for steps etc so had ended up with almost complete Heljan bogies. I utilised these as trailing bogies, but again with Hornby 14mm wheels and on this one the same style pick ups, So, onto the second Lima 33, I was a bit impatient to get hauling mk1 coaches with this one, to do all the work on the Hornby wheels, but wanted rid of the traction tyre, I used the original trailing wheels I had spare and glued the cog onto the back of them. I also had the idea of swapping sides with the insulated wheel so I didn't need a pickup on the cogged side. trailing bogie was again a cut down Heljan one but with better pickup arrangement , If all my drive wheels had been nice polished ones I'd be happy to leave this like it is, but the front set are the old brass ones and pick up dirt everywhere. I'll re do this at a later date..... Some interesting modelling going on here, I use to do similar mods to Lima 37/47s a few years back. Rather than use brass for the pick-ups, try Phosphor Bronze strips............ http://www.ebay.co.uk/itm/Slaters-1220-1-16-Thou-Phosphor-Bronze-Strip-10-Lengths-New-/132084602491?hash=item1ec0db167b:m:mrSx88qK6pAIWBjrK6y1Q_g Maybe cheaper at other sources................ Link to post Share on other sites More sharing options...
stu357 Posted March 14, 2017 Author Share Posted March 14, 2017 Some interesting modelling going on here, I use to do similar mods to Lima 37/47s a few years back. Rather than use brass for the pick-ups, try Phosphor Bronze strips............ http://www.ebay.co.uk/itm/Slaters-1220-1-16-Thou-Phosphor-Bronze-Strip-10-Lengths-New-/132084602491?hash=item1ec0db167b:m:mrSx88qK6pAIWBjrK6y1Q_g Maybe cheaper at other sources................ I think phosphor bronze would be a good alternative, it certainly puts less pressure on the wheel. every time I've used it I end up catching the end and bending it all out of shape though. I have tried .3 nickel silver wire which is less fragile but it did cause some issues with squeaking. Thanks though, I might try a brass attachment point with a PB or NS strip soldered to it next. Link to post Share on other sites More sharing options...
stu357 Posted March 14, 2017 Author Share Posted March 14, 2017 BTW, the Hornby/Lima trailing wheels are easy to turn down using a file and dremel to make the front face match the coach wheels. Link to post Share on other sites More sharing options...
stu357 Posted March 14, 2017 Author Share Posted March 14, 2017 I may have been over thinking this project! I was looking at some fine top hat bearings and realised they were readily available in a size to fit Hornby axles in the Lima chassis holes. the original Lima axle is 2.5 mm and the Hornby wagon/coach axle is 2mm. which means I can use the Hornby coach/wagon wheels on the drive bogie too. these bearings are exactly that size, and I was able to also use one to centre the drive cog when bonding it onto the wheel. As an experiment I've just re wheeled a Lima Plymouth shunter with Hornby wagon wheels! I know its not a 73 but it was something to test the theory on...... It worked pretty well really. there's one more 73 I've got so I might have another go! let me take a video of the shunter running. Stu. Link to post Share on other sites More sharing options...
stu357 Posted March 14, 2017 Author Share Posted March 14, 2017 here is the Plymouth with a CD motor, extra weight and Hornby wagon wheels fitted using 2.5 OD, 2.0 ID top hat bearings, shows up my dodgy track through the station more than anything.... https://youtu.be/ftJzKaqPPn8 https://youtu.be/RHg05ne92CU I elongated the axle holes in the chassis next to give it a bit of compensation. It clears the points a bit smoother now. Link to post Share on other sites More sharing options...
RMweb Gold Richard_A Posted March 16, 2017 RMweb Gold Share Posted March 16, 2017 Where do you get the top hat bearings from? I've had a quick Google, but my stupidity is letting me down! Link to post Share on other sites More sharing options...
RMweb Premium Vecchio Posted March 16, 2017 RMweb Premium Share Posted March 16, 2017 Like your ideas and how you did it. Now just add DCC and a decent stay alive and you have perfect performing locomotives. Was also thinking of replacement motors, but I am happy with the performance of the current pancakes. Vecchio http://www.rmweb.co.uk/community/index.php?/topic/120553-converting-old-lima-diesels/ Link to post Share on other sites More sharing options...
RMweb Premium 47137 Posted March 16, 2017 RMweb Premium Share Posted March 16, 2017 Where do you get the top hat bearings from? I've had a quick Google, but my stupidity is letting me down! I've had similar-looking bearings from Markits, they sell them as "2 mm bushes". They will convert a 2mm axle to fit a 2.5 mm space. Hope this helps, - Richard. Link to post Share on other sites More sharing options...
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