Rail Co

MOD: 7938

26 posts in this topic

Hello, I have made a Custom 9V Motor. My motor has been put on to my 7938 Passenger Train. It is using a PF motor with the metal wheels.post-27393-133269345103.jpg

This is the close up of the bogie.

This is how the power gets into the actual train. I am using little brass pieces with soldered wire onto it.

Thanks, Rail Co

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Doesn't it stutter or did you include enough capacitors ?!

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I have not tried to use capacitors, but it does stutter when the wheels are not clean. Any ideas for keeping the wheels clean?

Thanks, Rail Co

Edited by Rail Co

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I don't think the problem is the wheels. More likely that the track isn't clean enough everywhere.

There are several ways to clean the track. If you search for 'clean track' online there are a vast amount of solutions.

Another good idea would be to include a supercap, to prevent stutter.

Now please tell me where did you get those wheels and can i buy some too?

I would very much like to add some to my train.

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where are the metal wheels from?, i thought these would be fantastic to 9v-ify an emerald night, and keep the pf lge motor...

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If one has a mill one can make them quite well. Some colleague of mine (mech. engineer) also did it for me. B.t.w. making it able to slip through is important to avoid torque problems in curves.

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Well these I actually made, but I got the idea from a guy on Youtube with the name of mirekEnd. Here is the video I got it from:

I am sorry i do not know where to buy these :cry_sad:

Thanks, Rail Co

EDIT:With the problem of stuttering i also have a regular 9V motor and it works perfectly fine?

Edited by Rail Co

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Fantastic project Rail Co.!!! :wub:

This solution allows new constructive possibilities!

To increase the conductivity you can increase the number of wheels that picks the power from the rails perhaps adding a rear car.

Those metallic wheels are great!

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Well I have no friends with a mill. Couldn't I buy some wheels from someone here who can make some?

Reading the replies here it seems there would be more people who would like to buy them.

Anyone?

Edited by Jeroen vW

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Thanks to all who have said such kind words. :grin: If anyone has any other suggestions and comments feel free to share them!

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It would be great have an axle splitted by non-conductive material to fit the metal wheels on the same axis

That is a very good idea but I would not know how to do this.

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I thought of two possible solutions:

1) a plastic axle coated with metal hose (the problem is the final diameter of the axle covered)

2) cut off 3mm from the middle of the metal axle and rejoin it with a small plastic hose (like the ink pipe of BIC pen)

All the best

LT12V :classic:

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This is just what I was looking for. It would be nice to have the individual train control and motor power of Power Functions with the low weight (from lack of battery) and unlimited use of 9v.

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Well, the capacitors did not work...sadly :cry_sad:. Any other suggestions?

If any please let me know. I think it is the wheels though.

Thanks,Rail Co

Edited by Rail Co

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Well, the capacitors did not work...sadly :cry_sad:. Any other suggestions?

If any please let me know. I think it is the wheels though.

The problem is that only 2 wheels pick up the power. Since the track is not smooth, sometimes only 3 wheels touch the rails, like a 4 legged table on a rough surface. Usually this contact problem is avoided by using all wheel pickups, like the 9V train motor. This does require split axles or isolator rings between the axles and the wheels. This complicates pickup but gives the best results and this is what lego used for it's 9V system. For you the best would be the same solution that most home made car lighting systems use in the model railway world. That is using 2 bogies with 4 wheels with each bogie picking up only one side. This means that any 3 wheel combinations out of 4 will give 1 good contact with the selected rail and with 2 bogies this means 2 good contacts regardless of track conditions. This also works for turnouts, but pickup safety there could be improved with larger wheelbase bogies (2 or 3 studs between wheels).

just my 2 cents: Viktor

ps: i could use a few of those metal wheels myself...

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I did something similar a few years back for the lights on a observation car.

test wheel lgaugewhpkup7.jpg

Power pickup lgaugewhpkup6.jpg

I had a few wheels done up in steel by a machinist friend later. But it turns out that Lionel wheels are already a near perfect profile. I bought some at a train convention. Bought an old cabose for $3. And removed a bit of material from the front and back on my belt sander to make them overall thinner.

I wasn't interested in making a 9v motor at the time, as they were still avalible, but the metalwheels could be drilled out, and glue in a technic axle socket, then add a pair of brass leaf spring contacts to a PF train motor.

The problem is that only 2 wheels pick up the power. Since the track is not smooth, sometimes only 3 wheels touch the rails, like a 4 legged table on a rough surface. Usually this contact problem is avoided by using all wheel pickups, like the 9V train motor. This does require split axles or isolator rings between the axles and the wheels. This complicates pickup but gives the best results and this is what lego used for it's 9V system. For you the best would be the same solution that most home made car lighting systems use in the model railway world. That is using 2 bogies with 4 wheels with each bogie picking up only one side. This means that any 3 wheel combinations out of 4 will give 1 good contact with the selected rail and with 2 bogies this means 2 good contacts regardless of track conditions. This also works for turnouts, but pickup safety there could be improved with larger wheelbase bogies (2 or 3 studs between wheels).

just my 2 cents: Viktor

ps: i could use a few of those metal wheels myself...

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Hello again, yes I do think it is a problem with the wheels no conducting properly. Sadly I only have 3 wheels at the moment :cry_sad:.

Anyways I think I may put some sort of spring in to push the wheels as far as the will go to get them pressed against the track at all times

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You could add a supercap. These are high capacity capacitors. They are sort of like a battery, but much faster charging.

Precisely what you need.

Use the powerpickup suggestion from Impact.

You should also add more wheels. And if you make some more, please make a lot more, so all the afols here can buy some from you.

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Hello Just an update, The problem IS that one of the wheels does not go on the track all the way. So I am guessing that I will have to make a split axle sadly I cannot make more wheels right now :thumbdown: . I do not know when i can make more and it is a tedious process. Thanks guys!

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a gold cap (special capacitor) is a good idea for this purpose.

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As i am not good with electronic,

1. How would i go about installing this as i have 2 wires conected from the wheels throught the bogie into the train then cliped in by lego parts (so i do not solder it and can use the wire for another purpose later) which conects to the motor.

2. How small are thes because the have to fit in the train along with a weight for good traction of the metal wheels.

3. How much do these cost?

4. Making sure. A Capacitor is a device that stores electric charge yes?

Hey Sorry to bring this topic back up (again), but JopieK, could you send me a link to a store (preferably in the U.S) that sells gold capicitors or a capacitor that is 1. going to fit in the loco nicely. 2. keep enough charge that it will not die out!

Thanks again

-RailCo

P.S. Sorry for bringing this back up but I am really trying to get this to work properly and I am really close!

Edited by JopieK

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there is a good site about this: www.floodland I'm not sure where to buy it in the US but I get most of my components from Mouser.com (US based) or an alternative would be Farnell/Element14.

I have some experience with this and I used metallic wheels (custom made by a mechanical engineering colleague, now and then handy if you work at an engineering university). I found that it was difficult to maintain a stable contact with the rail: that is why one would use 'gold cap' capacitors.

B.t.w. please don't add two posts from yourself directly under each other, but use the Edit button for it instead (I merged the two posts)!

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Hi,

using capacitors to store electric energy is a good idea in general. The only problem with it is, that you need to consider the capacitor's polarity (for both, goldcaps and electrolytic types). On the LEGO 9V system, polarity is switched in oder to reverse the train, so you need an electronic circuit to load the capacitor and to maintain the train's current direction in case of lost contact to the rails - switching the capacitor's output polarity when required. Just soldering a capacitor in parallel to the motor won't have the desired effect but damage the capacitor (and most likely, the motor will still stutter).

When you use onboard controllers (like those used for DCC-controlled trains) you can easily use decoders with support for storage capacitors (e.g. ZIMO and ESU provide some types with this feature).

Regards,

Xris

Edited by Xris

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