Ha! Interesting that this popped back up. I had thought I had posted a followup.
Best result by far.... thanks to gmpullman...I picked up some of the caboose trucks with very nicely designed pickups and they really worked well. They work so well that I am going to pick up a couple more sets and continue with a couple more of my project.
My whole problem was that the axles on boxcars are so sloppy in the trucks compared to locos that even my very carefully constructed wipers were nothing like the great pickups on the caboose trucks from modeltrains.
Yes, you're picking up power on all 4 axles, but unless you have some really oddball wheelsets there, you are picking up from one rail on one truck, and the other rail from the other truck, so effectively only 2 wheels per side. The style of wiper that Mike showed trucly does pick up power from all 8 wheels on the car. It's too easy for just 2 wheels in the wheelbase of a typical freight car truck to both hit a dead spot at the same time. You'd have to insulate the pickups from each other, and run two wires from each truck, but it might be slightly more reliable to have each wheelset in the truck pick up from the opposite rail. I think Mike's style of wipers would be easier to implement though.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Thank you this is great.
Thanks. Yes, that is the system of wiring I used with those wipers. Each has a soldered lead up to the interior so the pick up is from all four axles and splitting the wipers allowed me to pick up from each track on each truck.
I found now that the problem is just one of too much play in the wheel sets and a typical (cheap) plastic freight truck as compared to a loco. I got good results by taping the flat steel weights from 6 freight cars on the top of the test car for experiement. The contact is almost flawless in this test. I thought about this when I noticed I could the Soundbug to work properly when I simply pushed down on the car at any time.
However, such a weighted car is not practical and I will be trying some of those nice caboose trucks with pickups soon.
Speaking of bridge rectifiers and caps, I see I had previously bought a selection of rectifiers ranging from 1.4 amp to 5 amp. However I am not sure that the rectifiers and caps can be successfully added to a soundbug.....although it has circuit connections to a typical 8 pin connector originally intended to mate with the Digitrax decoder in the designed use. I will have to do the research again on where to put rectifiers and caps in a decoder wiring setup.
In many cases, I make my own wipers out of Tichy phosphorbronze .010" diameter wire. If the truck is metal, I attach a small piece of PC tie to hold and insulate the wiper, as on the PSC HOn3 RPO/baggage truck.
When the truck is plastic, the wiper is attached by feeding the wiper lead through a hole in the bolster. The wiper is soldered to the lead and the whole assembly is fixed in place with epoxy. This is a truck from a Walthers trrop kitchen car is set-up to pick-up both sides.
The suggestion to include a capacitor to cut flicker is a good one. If you are using a bridge recitifier to get DC to power LEDs, just need to solder the leads to a cap across the + and - leads AFTER they come out of the rectifier and before the limiting resistor, while observing the proper match in polarity of the cap. Here's the install on that PSC HOn3 RPO.
Note that this is for a 12 volt lighting install, using a 3-LED segment cut from LED strips.
The cap requires DC power, so you'll need the bridge recitifier to install the cap. I get flicker-free operation with a cap as small as 47 uF. Here's a sketch of this simple circuit.
Mike Lehman
Urbana, IL
Thanks, fellows.
Yes I will try polishing up all the surfaces. That might do the trick.
And those caboose axles look like a good help. I will look at some fo those either online or down at the hobby shop.
Cisco,
I picked up a couple pair of these just to experiment with:
http://www.modeltrainstuff.com/Athearn-Genesis-HO-Caboose-Truck-w-Early-Generator-p/ath-g4592.htm
They have bronze inserts in the sideframe that the needle point axel ends contact so you get eight points of contact like some locomotives have that you mentioned in your post. You could probably trim off the generator moulding for use on a boxcar. They have rotating end cap roller bearings. Hard to see in the photo but they are sharp looking trucks!
A bit pricey but I feel they are worth the extra cost to get all 8 wheels picking up power. I hope Athearn makes a solid bearing type truck soon with the contacts for my older rolling stock. This is the best system for pick up you can get IMHO
Bowser makes a nice wiper kit for their trucks but they only pick up from four wheels total.
Good Luck, Ed
The wipers look fine as long as they're making good contact with the axles. The problem may be with the blackening which often acts as an insulator. Try polishing with a wire wheel at all the contact points, (the axles and the wheel treads).
Jay
C-415 Build: https://imageshack.com/a/tShC/1
Other builds: https://imageshack.com/my/albums
Try these. http://www.sbs4dcc.com/nscalewheelwipers.html
Thanks, Gentlemen.
No, the wipers each have wires and all are connected. In the case of the photos each truck is picking up from one track....both axles. This was a later test. Before that, each truck was picking up from the two rails....each axle (all 4) picking up from the track.
The decoder comes with a stay alive capacitor installed.
No, I think I will change the style of wipers.
I think you should try and find out how to instal a 'keep alive' capacitor on the decoder. You should be able to use a large one since the system is in a boxcar.
Also, try a little WD-40 on the wipers.
Elmer.
The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.
(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.
In your photos, the arrangement you have is only picking up power from two wheels per bogie, You probably need to pick up from four wheels per bogie - as in this example; (Scroll down to the Atlas UP caboose near the bottom of the page,)
https://www.google.co.uk/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&docid=Hpqrd-mRPKVh2M&tbnid=_EXJiTCQODw8YM:&ved=0CAUQjRw&url=http%3A%2F%2Fforum.atlasrr.com%2Fforum%2Ftopic.asp%3FTOPIC_ID%3D36521&ei=3MJ_U4TXG4nJ0AWIi4GACA&psig=AFQjCNHLAPsOzff2Z93rnUzp_E_KFjESEg&ust=1400968217584596
Trevor
Ahh, I thought I was being so clever. Experimenting with a Soundbug in a box car and powering it with track wipers.
All seemed well. Speakers and decoder work fine. Problem seems the wipers. I am using these ones from Richmond Controls. I even created a split effect so each truck would pick up power from both tracks. Well, performance is intermittent.....especially problematical over switches.
Now I had thought I had these pretty well configured like a locomotive, and even though the locos have flywheels to help them cruise along, these should have worked better.
Any suggestions on best wiper techniques to use? As you can see, these are adequately in contact with the pickup axles. There is no cross contact between wipers at all. Track is clean. Locos run fine in towing this. In these photos I have rearranged the wiring and axles to pickup from only one track per truck as a test, but this was no better.) Perhaps the weight was too light, but they are weighted more than most steam tenders on the layout.
I supppose the best arrangement would be to adapt some socket and hub pickup from the actual axle end like a loco. Maybe I can makeup some kind of pickup from loco leftovers.
Even this one that looks crooked is only contacting the correct wheel.