Pickups

I have used the suggestions from the below link. Helps a lot with DCC.

http://www.pacificcoastairlinerr.com/1879/bachmann_4-4-0/sound/

Store his link as an HTML in your PC. Once in a while his pages go away for a while. That way you will always have the page.

Rich

Dirty metal is the biggest

I have a similar model

And in fact rebuilding it is on my list of things to do one of these days.  I am looking forward to the progress on this one, as I have no doubt it will be up to your usual standards.

Will you be trying to keep it as close to original as possible, or will you rebuild it as needed for better operation?  If the latter, I highly recommend ditching the wire on the drawbar, and ideally removing the tender frame from the circuit entirely.  Also, although I know that you are not into DCC, you might consider adding a 9-pin connector and dummy plug in the tender, so that at some future date (if not now) the young man can upgrade if he choses.

Tender Modifications

I tackled the tender first. Bill, the modeler whose model this is, asked to have a new set of trucks installed. He believes they are Tichy trucks. He's not certain. They are all metal including the truck frame. These will replace the trucks on the tender. The ones that are on there now are a combination of metal and palstic.

In order to work on the chassis I needed to remove the plastic shell from the metal chassis. There is a tab by the drawbar screw that needs to get pried out in order to remove the shell. I don't like this set up. Since you'll want to remove the shell to get at the decoder that will be installed later. I feel this is an area that would eventually break. I'm going to modify that also. That'll be the last step.

 Once I got the shell removed I tried out the new trucks. Bill mentioned that the coupler was a bit low. Not to bad, but I'm going to make it better.

There's a lot of info in this next picture. The new trucks can not be screwed on with the screws that hold the Manuta trucks on. They have a built in washer at the top that is to large in diameter to fit inside the newer trucks mounting hole. One solution that might work would be to file down the head of the screw, Tedious at best.

Using my lathe I made a set of bushings with a 2-56 thread. They fit into the truck mounting hole. When the screw is tightened down it bottoms out on the bushing allowing a small amount of play for the truck to swivel and follow uneven track.

Here's a tip. When I buy screws for projects like this I always get the longest length that is they have in the size I need. Reason, I can always shorten a screw to the size I need instead of trying to find one of the right length. That's what the small piece of brass is for. I drilled and tapped for a 2-56 screw. I can now screw the screw  into the plate and cut it to length and file the burrs off. It's much easier to hold the plate than the screw to do this kind of mod on them. My source of fasteners is from http://www.microfasteners.com/  No affiliation, just a satisfied customer. Also it's not my only source.

Next I set up my mill and milled out the mounting hole in the tender. I went down approximately .250". The truck mounting plugs were then turned down to fit in the hole.

The bushings are ready for a test fit.

A check with the coupler height gage showed that the bushings need to have the shoulder trimmed back some to get the coupler to the right height.

A coupled of careful trim cuts and the correct height is maintained.

That ends this portion of the modification. Next will be the design and build of wheel wipers.

Bernd

To answer your questions Ken

"My usual standards", Yiiikes Ken. You're putting stress on me now.  But of course I will.

The engine will not get changed in appearance. It will only be an up-grade on the drive train. Bill has already installed a can motor in the engine. He did a fine job of it too. When blocked up and power is applied it runs very smoothly and quite. I plan on a video or two of it running during this mod.

Bill sent a long a Lenz decoder he wants me to install. I'm a little hesitant since I've never done this before. Perhaps I'll have the courage to do that by the time I get all the mechanical work done.

Bernd

Tender Truck Wheel Wipers

The next pictures will show the build up of truck wheel wipers and mounting.

The wipers are made up of a strip of .006" thick phosphor-bronze sheet. I used a pair of scissors to cut strips approximately 1/16' to 1/8". Try to keep them as narrow as possible. I cut out small squares of brass with a clearance hole (#50 drill) drilled to clear an 0-80 screw and a piece of black wire from computer ribbon cable make up the wiper.

On the left is a finished truck with a set of wipers fastened to the truck with 0-80 shortened screws. On the right are two more wipers and two spacer washers that go under the brass square to set the wiper high enough so it won't rub on the wheel axle.

This shows the long, 3/4", 0-80 screws I use for fastening the wiper to the truck. Again a small fixture is made to hold the screw for cutting to length and filing the burrs off. A hole is drilled in the top of the truck beam and  tapped 0-80. The wiper is attached and then the screw is marked for a cut off length and the wipers are marked where to shorten them.

I bent the wipers to mark where to cut them, do the same for the long screw.

Four holes were drilled into the tender chassis to run the wires through. Here the first truck is being readied to fasten to the bolster.

And here it is all complete with wires installed through their holes. You'll note that I ran the two wires at the front of the tender, where the draw-bar screw is on the same side as opposed to the rear truck wires. That was done because it's close to the front portion of where the coal doors are. The trucks swivel freely, although with a bit or resistance do to having to twist the wires ever so slightly. Nothing that will interfere when the tender is being pulled by the engine.

Next up will be the build up of the engine wheel wipers and there mounting on the frame.

Bernd

Well done

Adding wipers to all of the tender wheels is probably the #1 thing you can do to improve the way a steam loco runs.  I've added quite a few, in a variety of styles, and that's probably one of the neatest looking jobs I've seen.  My philosophy is usually "If it works, who cares how it looks."

Tender Wheel Wipers

Thanks Ken. They could have come out a bit better. Next ones will be built in a jig so they will look alike. Working on the engine wipers now.

Bernd

Engine Wheel Wipers

I didn't think I'd get this far today.

I made a retainer plate from a piece of PC circuit board, drill the holes out and fastened it to the engine bottom. This will make installing the wipers much easier.

I drew up four wipers on my cad system. Printed them out and glued them to a piece of .006" thick phosphor bronze sheet. They were then cut out with scissors.

The wipers were bent to shape and soldered on. The front wipers have been soldered on already.

Both front and back wipers installed.

Two holes were drilled so wire could be run into the firebox for hook up later.

That's it for the installation of the wipers. Next on the agenda is to temporarily wire it all together and take a test run with straight DC to see if there was an improvement. I'll make a short video of that occasion.

To be done yet is the installation of an LED headlight and a Lenz decoder and all the associated wiring.

Bernd

Video of First Run

Watch as the steamer makes it's first run at slow speed through a commercial switch with a dead frog. It does slow down, but that's because of a tight spot in the frog area. As you watch you'll hear the chant of an Alco T-6 idling in the background.

This is how smooth a 4 wheeled switcher, now with 12 wheel pick can run. The can motor also helps a tremendous amount. Enjoy.

Bernd

Excellent Workmanship

Excellent work to make a very smooth-running switcher!  Truly appreciate your how-to instructions, great detail.  I have a few locomotives that need your improvement methods.  Are the inside surfaces of your tender wheels painted and you need to remove the paint (just not yet shown) or is it a conductive coating?

Great work, very helpful.

Chuck J.

An Alternate for Better Performance

Bernd,

Sometime along the way, try experimenting with dual or triple phosphor bronze wires replacing the flat phosphor bronze wiper. You may find a bit better performance as at least one of the wipers is likely to maintain contact as they go over metal irregularities in the wheel or once it starts to collect dirt. High-end electrical devices that require electromechanical contacts will use this technique (bifurcated or trifurcated contacts). It makes a difference in pick-up performance for me-- better, but not wildly better, for just about the same effort. The only thing better that I have found, are spring loaded "pogo pin" contacts, which are often just too long for many model applications.

Another thing I've tried to minimize contact bounce, is to polish the metal surface over which the contact will run. All these efforts are to minimize contact bounce (yes that's what it's called) which has the added benefit of reducing current arcing, and metal pitting from the arcing over time.

By the way, nicely done-- as now expected!    Have Fun!

Best Regards,

Geoff Bunza

The Wheels

Chuck,

Thank you for the comment. Much appreciated.

The wheel set is actually a combination. Bill told me that the truck frame could be a Tichy or Kadee product and is Delerin plastic, not metal, as I had first thought. The metal wheels were scrounged from a Bachmann anniversary boxcar. They are blackened and are conductive. No need to remove anything.

Bernd

Better Performance

Geoff,

Always good to hear from you and always grateful for the info you pass along. I remember seeing something of which you speak. I can't recall where though. Probably some high end device I took apart that wasn't functioning anymore.

Those would be very tiny then to rub against the wheel, right? Sounds like something that could etched. Mmmmm. Ideas are flowing.

Thank very much. (you just increased my stress level )

Bernd

Nice work Bernd!

Nice work Bernd!  I also see several ideas for better pickup on diesel locomotives. One would think that with at least 8 wheels picking up power from the track, that contact would not be an issue, but it still is.  Short of replacing wheels for better ones I have been adding additional wipers to my engines.  My question is, what is your source for the product and what size should I consider in thickness?

Source and Thickness

Nelson,

Thank you for the nice words.

I'm assuming you are talking about the phosphor-bronze sheet? I've had that for some time. I need to look for a new supply of it. The thickness of the sheet I'm using is .006" thick. I would use thinner if it is available, such as .003" thick. I will look and see if I can source some. I have several metal suppliers I've used in the past that may carry it. I'll post the info once I have it.

Bernd

Found some

Nelson,

This is one place I get some of my raw stock for projects. They have .005" thick on a roll 6" wide and 50" long for $14.24. That would be enough to last several life times. Here's a direct link to their page.

http://www.mcmaster.com/#shim-stock/=pl7nny

I have done business with them many times and I'm a satisfied customer.

I did a Google under "phosphor bronze sheet" and came up with several suppliers. K & S is sold by some major on line hobby shops such as Tower Hobbies, Rider's Hobby Shop & Hobbylinc.com

 Hope this has helped.

Bernd

An Observation

While running the engine backwards very slowly I noticed an oscillation in the motor shaft. It was oscillating back and forth. There looked to be about .030" or more movement back and forth.

Here's a picture of how much travel the motor shaft does.

This will give some oscillation through the whole drive train giving a small bit of jerky ness while under motion. The only way to cure that would be to open the motor and install washers on the shaft and that's not going to happen with this motor since there's no way of opening it without destroying the motor. Just another point to consider when trouble shooting drives.

Bernd

U-shaped washer?

Would it be possible/practical to make a "U" shaped thrust washer which takes up some of that slack, and sits into the middle of the drive somewhere?  Alternately, could you add a thrust washer/surface (or a ball bearing, perhaps) pressing against the end of the worm?

What is that chunk of brass above the worm?  Working on something special there, Bernd?

That chunk of brass

Not actually. It's to hold the cylinder assembly on the frame while handling the chassis. The weight that is inside the front of the boiler when it sits over the cylinder block has a threaded hole that holds everything together. Trouble is the screw is to long to use with just that weight to hold down the cylinder block. If you don't fasten it down the valve gear falls off and that is one sob to get back in position again.

All of your suggestions would take a bit of time to do and tweak. Something I don't want to get into with this engine. If you'd have seen it run when I first got it you'd say this is a 110% improvement. It really doesn't effect the engine to a great extend. You might see a jerky action if the engine was going down grade with a cut of cars. I just happened to notice this while I was watching up close, other wise I may have never seen it. I thought it would be a tip to pass along for those wondering why their engine was still a little bit jerky after an up-grade such as this.

I'm thinking I may take my 2-6-2 Prairie Manuta I have and doing the same up grade in it, minus the DCC. I'd probably install R/C.

Bernd

LED Headlight Installation

Bill wanted a Miniatronics 3mm YELOGLO warm white LED install. So here's what I did.

This is the weight that's in the front of the engine and it has the light bulb in it. I haven't figured out what the square block was for over the bulb. The smoke box cover had the cast in headlight and a plastic lens.

That little square block was just siting on top of the bulb. Talk about antique lighting.

On the bottom you can see where the screw goes into to hold the front end on. Also provided is a nice wire run around the screw hole.

The bulb pops out easy. The plastic lens took a little more effort.

The LED is being prepared for installation where the bulb was. The red arrow points to the area I needed to remove some material so it would fit into the headlight. I also had to file the inside of the headlight to get a snug fit for the LED. The leads were cut and a slight bend was put in them so they would fit down the hole where the light bulb was. Heat shrink tubing was placed over the solder joint.

You're looking at the top of the weight. The LED has been firmly pushed into where the plastic lens used to be. The wires are fed down through the hole where the bulb was.

The wires were run through the wire channel and held in place with a couple of dabs of hot glue. It helps to keep the wires in place for assembly.

I soldered a 8.2K 5% (gray-red-red-gold) resistor on the plus side of the LED. Then another dab of hot glue to hold the resistor and wires up out of the way. A dual home made plug was added for easy removal of the shell for maintenance purpose.

Some will question the size of the resistor. Since the manual doesn't state a voltage output for the bulbs I assumed at least 12 volts. I used a 14 volt power supply to find the correct resistor to give a more dimmer light.

That's it till next time I install the decoder in the tender.

Bernd

The block looks like a light

The block looks like a light direction control thingy. 

Concentrates the light forward.

Not that you need it now!

Electrical Problem

I discovered that that can motor was not insulated from the frame. I thought that with the plastic tabs that hold the motor brushes that the motor was insulated from the frame. The picture shows where the wires get soldered to.

Also the screw that holds the motor on would be an electrical connection to the motor mount. I made one out of black Acetal, a very tough and slippery plastic. They use this as a substitute for ice skating on. The original metal screw is on the left. The one made from Acetal is on the right. The screw is a 2-56.

Then I used a piece of .010" thick styrene for an insulation barrier on the bottom of the motor mount.

I glued it on with ACC and cut off the excess material and mounted the motor back on the chassis.

I checked with a meter and I had no continuity between the motor casing and the chassis.

I'm working on mounting the decoder in the tender and working out how to run the wires. First I need to order some material to make miniature plugs.

Bernd

Gear mesh, and plugs

Did the additional .010" make any practical difference in the gear mesh?  If so, would adjusting the motor backward by a few thou solve the problem?

If you are looking for plugs, you could do worse than the TCS 6-pin connectors.  That's what I've decided to standardize on for all steam locos with decoders in the tender and motors in the boiler.  I can send dimensions, photos, etc., as needed.