Lighting Trains

[gavino200]

10 minutes ago, EdF said:

Couldn't you add caps to the Dani method?  The ones on digitrax sound decoders aren't that big.

 

Yes, that's what I'm planning to do. I'm just curious about these things. The Dani method is untested in my hands. I think it'll work for me but you never know. Dani is a very talented chap.

[cteno4]

Keep the cap voltage twice what the max voltage what you are feeding it to be safe. Voltage on the cap is basically the max voltage you can charge it with. But this does make the size get bigger as you need 2x more cap (ie volume) for a 2x greater voltage cap.

 

tantaliums are nice as they can be compact in smd form and less prone to melting down or “popping” (ie exploding, you hear a pop and find part of the cap has exploded out) than electrolytic. But tantilums are more expensive, especially as you increase the capacitance.

 

one of the forum members does great stay alives for locos and cameras by packing all the extra space with high cap tantaliums.

 

cheers

 

jeff

[gavino200]

3 minutes ago, cteno4 said:

Keep the cap voltage twice what the max voltage what you are feeding it to be safe. Voltage on the cap is basically the max voltage you can charge it with. But this does make the size get bigger as you need 2x more cap (ie volume) for a 2x greater voltage cap.

 

Thank you. Any advice on the capacitance number? Number of uF units?

 

3 minutes ago, cteno4 said:

 

tantaliums are nice as they can be compact in smd form and less prone to melting down or “popping” (ie exploding, you hear a pop and find part of the cap has exploded out) than electrolytic. But tantilums are more expensive, especially as you increase the capacitance.

 

Great. I'll stick with them. 

 

3 minutes ago, cteno4 said:

 

one of the forum members does great stay alives for locos and cameras by packing all the extra space with high cap tantaliums.

 

 

Interesting. Is this with DCC or DC? "All the extra space" sounded dramatic for a second. But I guess that's likely about one capacitor if you're lucky.

[Kiha66]

Like so many things in this hobby, turns out ken has already done a good write up on such a circuit.  His idea of adding the second diode bridge so the keep alive doesn't require modifying the kato light board is a good simplification that seems obvious in hindsight. 

http://www.sumidacrossing.org/ModelTrains/ModelTrainDCC/CarInteriorLighting/CarLtCapCircuit/

[gavino200]

46 minutes ago, Kiha66 said:

Like so many things in this hobby, turns out ken has already done a good write up on such a circuit.  His idea of adding the second diode bridge so the keep alive doesn't require modifying the kato light board is a good simplification that seems obvious in hindsight. 

http://www.sumidacrossing.org/ModelTrains/ModelTrainDCC/CarInteriorLighting/CarLtCapCircuit/

 

Thanks Kiha. After reading Ken's page I'm still a bit fuzzy. Ken is mostly concerned with physical size, price, and voltage. His thoughts on Capacitance is fairly vague. He talks about using a 560uF 10 mm cylindrical cap, and then says he went to a 360uF 8mm cylindrical cap to cut down on price. He then states that Tantalum SMDs were available in 220uF but that he went with a 100uF because of price considerations. He says the 100uF is ok, but isn't more specific.

 

I have questions about the following:

Do you get current for a longer time - a longer "stay alive"with more uF? ie is higher uF better?

Is there a value of uF that is too high? Will high uF give too high a current for the LED?

 

Also, I currently have 100 units of 220mF SMD Tantulum 40 V caps. It's not a big deal if I don't use these. Is there a problem if the voltage is "too high"?

 

Also, should a different capacitor be used for Lighing vs. Motor decoder use? 

 

My issues are:

1 Size - so I'll use an SMD - size then shouldn't be an issue

2 Function - I want it to work as well as possible. ie smooth current.

 

Regarding price. I don't see the point in spending hundreds of dollars on a train and then pinching pennies on components. So I'll shop around but it won't be a main issue.

[Sheffie]

Yes, the uF rating is a measure of the energy stored, so doubling that will double the time that current will flow, if the current stays the same... but will it?

 

There’s a chance that a different capacitor type would have a lower internal resistance, which could result in higher current flow and potentially burnout in the LEDs. I don’t know enough about train lights to answer that.

 

But the voltage won’t go up with a different capacitor, so that won’t be a problem. It will never be higher than the supply voltage 

[chadbag]

3 minutes ago, Sheffie said:

 

There’s a chance that a different capacitor type would have a lower internal resistance, which could result in higher current flow and potentially burnout in the LEDs. I don’t know enough about train lights to answer that.

 

Yes, but the internal resistance of capacitors is generally in the low range and the other resistances involved are an order of magnitude higher or more than the internal resistance, so any small differences there should be negligible???

[Sheffie]

Yeah, I think you’re right. I didn’t know about the relative resistance values. 

 

At the end of the day, more uF is better, and that’s about it. 

[cteno4]

Resistor should be between the cap and leds and this then is not an issue as the resistor will limit the current properly. 

 

jeff

[gavino200]

So far I only have experience lighting Kato trains. I have some idea how the lighting for Tomix cars work. But I opened up a couple of European cars tonight to see what's involved. 

 

Not wanting to reinvent the wheel, does anyone have any idea how Fleischmann lighting works?

 

Graham Farish cars don't look like they're designed for lighting at all.

 

Fleischmann 

 

 

Graham Farish

 

 

 

[chadbag]

Which Fleischmann wagon is that?  I suspect I have the same one to open and look around.  

[gavino200]

1 minute ago, chadbag said:

Which Fleischmann wagon is that?  I suspect I have the same one to open and look around.  

 

It's an epoch VI IC wagon. I just grabbed it at random to take a look. I'll look tomorrow at the model number, and maybe open a few more to see if they're all the same. There's a little perforation in the plastic about three compartments from the right where you can see some metal shining through. I think that must be the key. But I've no glue how it's supposed to work.

[chadbag]

Yeah I saw it was an IC wagon.  If you can get me the part number I will check my stash so I am looking at the same one.   Fleischmann wagons often have a sticker on the bottom that has the part number on it as well.

 

On the Graham Farish see if it has contacts in the bogies of some sort that pick up power form the wheels.  That will tell you if it is made for internal lighting or not.

Edited February 8, 2019 by chadbag

[Beaver]

6 hours ago, gavino200 said:

Graham Farish cars don't look like they're designed for lighting at all.

 

I would expect that is indeed the case. UK models rarely have any working lights etc since there is (in my experience) very little demand for them.

[nscaler711]

Have any of you guys tried using COB LEDs for lighting cars yet? They seem like theyd be perfect for our use.

 

[gavino200]

10 hours ago, chadbag said:

Yeah I saw it was an IC wagon.  If you can get me the part number I will check my stash so I am looking at the same one.  

 

It's model number 861803

[gavino200]

1 hour ago, nscaler711 said:

Have any of you guys tried using COB LEDs for lighting cars yet? They seem like theyd be perfect for our use.

 

 

I haven't heard of those. Can you tell me more about them?

[chadbag]

1 hour ago, gavino200 said:

 

It's model number 861803

 

So I took mine apart.  Above the bogies on each end you can see some metal beneath some plastic tabs.  I believe that is where the lighting attaches.  If you take the bogies off, you see two metal plates for power pickup.  But the actual power swipe thing is not installed either (the thing that rubs the axles to get the power from the axles) so there is no power transmission from the wheels to that underlying metal plate that is built in.  So you will need to install a contact plate on the bogies (see pic for the sort of thing I mean).  And some way for the power to go from that plate to the pickup point under the body.  (I suspect you are meant to bend the contact plate up to wipe the underside of the pickup point).

 

If you take the bogies off, be careful to put them on correctly when you put them back on.  The insulated wheels should be on opposite sides on opposite ends of the car, so you get power from each track.

 

Given the lack of any "dead space" (no windows) on the body, it will be hard to put wiring (and in my case a decoder) in without being able to see it through the windows.

 

ETA:  The particular contact wipes shown here are not particularly suited for the Fleischmann, but it is this sort of thing.  I just tried to test fit one to see how it worked and the center hole is too small and there is no good way for it to contact the body contact point.  I'm going to try and find some thin metal at the hobby stire and design my own.  Looking at the truck it will go on top of the truck and have two wide arms that come down to the axels out near the wheels.

 

 

Edited February 8, 2019 by chadbag

[chadbag]

So for the particular Fleischmann car Gavin showed, this is the factory lighting kit:

 

https://www.fleischmann.de/en/product/227085-944701-0-0-0-0-0-003007001-1/products.html

 

And here the instructions on installing it.  You can see what they have for "springs" for electrical contact by looking at the images.

 

https://www.fleischmann.de/doc/an/2/de/BA_944701_202820.pdf

 

 

[gavino200]

6 hours ago, chadbag said:

this is the factory lighting kit:

 

I've been thinking a bit about this today while I was working. I agree the kit is quite fancy. However two issues with that. First, they're really quite expensive. Second, I've been unimpressed with some fancy Fleischmann items before - namely the Fleischmann function and motor decoders that don't work with a Digitrax system. I'm a bit shy on Fleischmann electronics at this stage.

 

However, it looks like Fleischmann essentially force us to use their product by not equipping the carriage trucks with pickup strips, and also not selling the pickup strip separately.

 

It looks like it would be fairly doable to pass wires at floor level from the pickup location to the end of the carriage where the pickups are located in Kato trains. From there they can be routed upward. Likely you'd have to drill two tiny holes in the seating on each side. But this is moot as you need to acquire the truck pickups somehow.

 

Unless there's some way to acquire the truck pickups, it looks like I'll be buying eight of these kits. 

 

I'll have to look inside my Epoch IV IC coaches to see if it's the same. 

 

 

 

[gavino200]

10 hours ago, nscaler711 said:

Have any of you guys tried using COB LEDs for lighting cars yet? They seem like theyd be perfect for our use.

 

 

From a rudimentary search it looks like the main advantage of COB LEDs is super brightness. I find that for train lighting, it's actually more of a challenge to tone down the brightness to a level that looks somewhat realistic.

 

But if you know of a good application of these devices, I'd love to hear about it.

[gavino200]

15 hours ago, Space Beaver said:

 since there is (in my experience) very little demand for them.

 

You may be right. But it seems a bit odd to me. Why wouldn't British people want lights in their trains? Everyone else seems to like them.

[chadbag]

I am going to fabricate my own pickup strips for wagons like the 861803.  I've ordered some thin steel, brass, and copper from eBay.  When it comes I'll see what I can come up with.  I am not buying $20-$30 lighting kits.  $7-$8 for KATO ones is more than enough.

 

Here is a Fleischmann 861103 image.  Notice how these bogies are attached with a screw?  This is the sort of truck the Digikeijs pickup strips I showed above were made for.  The strip rubs the axle, and brings the power to the screw that holds the trucks.  You should be able to get to the screw from inside the wagon and pick up the power there.  Unfortunately I have not yet managed to get the shell off to take a look inside.

 

 

[gavino200]

7 minutes ago, chadbag said:

Unfortunately I have not yet managed to get the shell off to take a look inside.

 

 

Do you own one of these?

 

https://www.amazon.com/Professional-Non-Abrasive-Spudgers-Anti-Static-Tweezers/dp/B00PHNMEMC

[gavino200]

8 minutes ago, chadbag said:

I am going to fabricate my own pickup strips for wagons like the 861803.

 

I'll join in with this endeavor.