Progress on my tramway.

I just wish my little open frame rotary converter would arrive. Its being custom made and will give me 13.8VDC at 25amps. It looks exactly like something out of an old Tram depot. I also have a small mercury arc rectifier that I wanted to use. It came out of an old WWII radio. Trouble is it wont arc up under about 180VAC and that gives me way to much voltage when rectified ,but it looks very prototypical....
 
Yeah well.... best laid plans and all that stuff.The chap who was making my cute little converter says he is having problems with the castings. He has had several done using lost wax and they look great but are "chilled" and fro some reason very hard and for the project you need soft cast iron that will not hold the magnetism, or convert into a magnet... Some it looks like I'll just have to use a switchmode power supply till something more "authentic" comes along.
 
DSCF2182 (Medium).JPG DSCF2184 (Medium).JPG DSCF2185 (Medium).JPG Ok so I have had to rig up a temporary power supply as there are technical issues with the "pukka' one.... But the yard lights now work which is handy. Ask anyone who has had to put the pole back on the wire in the darkness of night with no light.... I have made up a device ( very technical) that lets me swing the trolley pole on the far road and put the poles back on the wire, it was very difficult to make, a 10mm length of dowel with a groove in the end, does the job........
So other matters that are now coming to light are the trams lights. They are the right intensity to be used outdoors in sunlight but far far to bright for indoors so I'll have to dig around in my cache of resistors and find the piece de resistance that gives them a more subdued glow.
First priority is to get the rest of the Overhead up though...
 
Last edited by a moderator:
Loving it
 
DSCF2202 (Medium).JPG DSCF2210 (Medium).JPG DSCF2211 (Medium).JPG DSCF2214 (Medium).JPG All the overhead has been strung and now awaits the Dremel and rotary abrasive rubber to remove excess solder and any little dags that tend to dewire the trolley wheel. The Horse tram trailer made an excellent rolling hand steady for soldering the wire to the ears, without it I needed an extra hand to hold the soldering iron steady, something I have to discuss with my surgeon. I have done a little more work with trolley wheels actually and I shall make new ones with a 3mm ball bearing in the centre and a nickel silver "wheel" pressed onto the bearing to help them stay clean. The profile will also be changed from the wide "U" shape I was using to a deep "V" shape that will hold the wire and wheel central so that when the wheel enters or exits a frog the wheel will be on centre under the wire and not decide to run along the edge of the frog and dewire. This profile will also theoretically double the contact area on the wire as both "sides" of the trolley wheel groove will be in contact with the wire. I have done some experiments with what happens with the current pick up with wheel and wire using an oscilloscope.... No wonder the R/C receiver was dropping out the graph looks like a saw blade with about 10 - 20 "brown outs" every 300mm......So to get an idea its like running the tip of a finger over a blunt tooth saw blade... So I'll have to dig out my supply of 5V 1 farad super capacitors and connect them across the Receiver battery circuit....
I have also discovered some R/C switches suitable to turn the headlights on and off for about $3.50 so I've ordered one to see what its capable of, It would be nice to be able to use the AUX channel to do this.
For reasons yet to be understood the trams that have not run for a few years don't seem to respond to the R/C commands, they may have lost their "plonk" and have to be rebound to the transmitter. The transmitter has to be reprogrammed anyway....

But its all looking good, I'll replant the tree when I've finished cleaning up the overhead.

These are the switches, they are 2 channel from one channel so should be able to switch headlights end to end.
https://www.ebay.com.au/…/Two-Channels-Contro…/162691785301…
 
Last edited by a moderator:
Just been thinking a little about your Car Barn. On such a modest line 3 full length roads might take up a lot of space (and building time) Have you thought perhaps of 1 road at the rear being sufficient to hold 1 car and the other two just being a few inches long giving the impression of a much larger Barn than is actually the case. The two shorter Roads could have pictures of the inside of a real Barn pasted in with whatever car or empty as you choose thus giving a rather nice illusion. I have done something similar with my Gernrode Engine Shed.
 
I have it done now.... I have room at the terminus ( for want of a better word) for 4 cars to wait... So I could keep 8 cars on the layout but it would be like one of those number games with one vacant spot Lol.... I'm pushing the domestic boundaries as it is. It was supposed to be a simple shelf to store trams but I have pushed that boundary beyond its Youngs Modulus. ...
 
No72 said:
All the overhead has been strung and now awaits the Dremel and rotary abrasive rubber to remove excess solder and any little dags that tend to dewire the trolley wheel. The Horse tram trailer made an excellent rolling hand steady for soldering the wire to the ears, without it I needed an extra hand to hold the soldering iron steady, something I have to discuss with my surgeon. I have done a little more work with trolley wheels actually and I shall make new ones with a 3mm ball bearing in the centre and a nickel silver "wheel" pressed onto the bearing to help them stay clean. The profile will also be changed from the wide "U" shape I was using to a deep "V" shape that will hold the wire and wheel central so that when the wheel enters or exits a frog the wheel will be on centre under the wire and not decide to run along the edge of the frog and dewire. This profile will also theoretically double the contact area on the wire as both "sides" of the trolley wheel groove will be in contact with the wire. I have done some experiments with what happens with the current pick up with wheel and wire using an oscilloscope.... No wonder the R/C receiver was dropping out the graph looks like a saw blade with about 10 - 20 "brown outs" every 300mm......So to get an idea its like running the tip of a finger over a blunt tooth saw blade... So I'll have to dig out my supply of 5V 1 farad super capacitors and connect them across the Receiver battery circuit....
I have also discovered some R/C switches suitable to turn the headlights on and off for about $3.50 so I've ordered one to see what its capable of, It would be nice to be able to use the AUX channel to do this.
For reasons yet to be understood the trams that have not run for a few years don't seem to respond to the R/C commands, they may have lost their "plonk" and have to be rebound to the transmitter. The transmitter has to be reprogrammed anyway....

But its all looking good, I'll replant the tree when I've finished cleaning up the overhead.

These are the switches, they are 2 channel from one channel so should be able to switch headlights end to end.
https://www.ebay.com.au/…/Two-Channels-Contro…/162691785301…
Click to expand...

Looking good! There's something about watching overhead and trolley poles that is satisfying, must be a tramway thing...

I had a similar experience with trolley wheels, with brass wheel on copper wire. The contact can certainly be erratic, especially when the wire is dirty. All of my trams have two 47000uf capacitors in parallel to keep the voltage to the radio steady, it seems to do the job. Running is fine, but if you stop on a patch of dirt the capacitors discharge and the radio drops out. A workaround was to wire the lighting circuit to bypass the capacitors, so if you see the saloon lights flicker off you know the tram is insulated (just like real life!) and can move forward a bit.

I have a mixture of wheels and fixed heads, I found the most critical dimension for tracking through frogs was the width of the wheel. Too wide and it hits the edge of the frog on entry, too narrow and it doesn't pick up the wire again on exit. It's interesting to hear about other people's experiences with this, I've learned through trial and error that there's quite a science to trolley poles and wires, and setting them up to work well!
 
Melbournesparks said:
Looking good! There's something about watching overhead and trolley poles that is satisfying, must be a tramway thing...

I had a similar experience with trolley wheels, with brass wheel on copper wire. The contact can certainly be erratic, especially when the wire is dirty. All of my trams have two 47000uf capacitors in parallel to keep the voltage to the radio steady, it seems to do the job. Running is fine, but if you stop on a patch of dirt the capacitors discharge and the radio drops out. A workaround was to wire the lighting circuit to bypass the capacitors, so if you see the saloon lights flicker off you know the tram is insulated (just like real life!) and can move forward a bit.

I have a mixture of wheels and fixed heads, I found the most critical dimension for tracking through frogs was the width of the wheel. Too wide and it hits the edge of the frog on entry, too narrow and it doesn't pick up the wire again on exit. It's interesting to hear about other people's experiences with this, I've learned through trial and error that there's quite a science to trolley poles and wires, and setting them up to work well!
Click to expand...
Yeah... the wheel on wire thing turns me on... In the real world I'm totally indifferent to trams without at least a trolley pole. In G scale you can actually hear the wheel singing on the wire... I use a 1F x 5v supercap to keep the radio alive.. https://www.ebay.com.au/itm/2PCS-1F...581794?hash=item239f3f4f62:g:QaoAAOSwWhVa2b80
 
DSCF2031 (Medium).JPG DSCF2225 (Medium).JPG Soooooo after all the excitement I'm having a clean up ready to start sorting the trams out, re plonking them, new lighting resistors etc etc and I have got some surplus stuff. Among it are some overhead frogs, they have all got 2.5mm wide grooves, anyone interested? I also have street gas lights too. And heaps of signalling stuff. Open to offers... Buyer pays actual postage costs.
 
Last edited by a moderator:
DSCF2231 (Medium).JPG I've had a fiddle around with the lighting resistors and now I dont get blinded. Now the calculator told me to use 240Ohm but in reality I used 820Ohm. I dont like the colours on either of them, much prefer green and brown or chocolate and gold but I'm told I have to choose resistors by value and not if I like the colours of them.... So with another few hours work Car No2 will be able to go back into limited service. I've lost the jumper lead too, have to make up a new one so 1 & 2 can run as a coupled set, compare the pair.
 
Last edited by a moderator:
Now put your specs on and have a look at this. this is the bearing to go in the, as yet to be made, trolley wheels, smaller than a match head. And no, before you ask I have no idea how they got the balls into something so tiny... But hey they are kind of cute. $3.50 for 10 on eBay, $7.85 each at the local bearing shop and business wonders why people shop on line....
 

Attachments

  • DSCF2233.JPG
    DSCF2233.JPG
    115.5 KB · Views: 0
No72 said:
Now put your specs on and have a look at this. this is the bearing to go in the, as yet to be made, trolley wheels, smaller than a match head. And no, before you ask I have no idea how they got the balls into something so tiny... But hey they are kind of cute. $3.50 for 10 on eBay, $7.85 each at the local bearing shop and business wonders why people shop on line....
Click to expand...

Miniature engineering marvel.
 
You must log in or register to reply here.
Back
Top