MDC/ROUNDHOUSE locomotive rebuilds

[Schraddel]

Glen,
about performance of traditional open frame motors and their eligibility for DCC, i recommend to replace them with suitable can motors.
Mark Schutzer has written and published several tutorials about. To which i agree to 100% as a result of my own expieriences. Some of this old open frames can pull about 1.3 Amps when just running outside the loco with no load applied. At least you have to sqeeze a G-Scale decoder into which is able to handle the load.
The cause is the magnetical weakness of the magnetic forces of the permanent magnets developing in the course of time. These motor draw then a lots of amperes, but have very poor performance output. As compensation they can get pretty hot when running longer than 2 minutes. Not the equivalent of the amps they guzzle.
<!-- m --><a class="postlink" href="http://markschutzer.com/Brass_Clinics/InstallingDecoders2013.pdf">http://markschutzer.com/Brass_Clinics/I ... rs2013.pdf</a><!-- m -->
<!-- m --><a class="postlink" href="http://markschutzer.com/">http://markschutzer.com/</a><!-- m -->
He deals with brass, but with the MDC Locos it is just the same about the technical and electrical problems. The only difference is, that the MDC loco are not out of brass sheet, but of solid die cast.

My 2 cents

Greetings Lutz

[cnrglen]

Hi Lutz, thanks for following along. Prior to the install my DCC guy took the 4-6-0 and did a check on it for it's suitability for installing a DCC decoder with the open frame motor. His conclusion was that it pulled a bit less than 1 ampere and he could not stall it under load. It has similar performance to an Athearn gold can motor. This fellow has a fair amount of install experience as he worked as an installer in a hobby shop for a number of years.

[doctorwayne]

Hmm....I was sure that I replied to this thread around 5:00AM this morning - must've been dreaming.

You can lower the current draw and improve the performance of open frame motors simply by replacing the stock magnets with rare earth magnets.
I did so with this brass switcher...



With the new magnets (and quite a bit of added weight), this little sweetheart has become a real monster. The starting voltage has dropped and even though my layout is DC, it crawls just fine when needed and pulls like an ox.
Micro Mark offers such magnets, but, in Canada at least, you may be able to get them at Lee Valley, Princess Auto, or Canadian Tire.
The procedure is to stack as many as will fit in the space where the original magnets were, then make-up any remaining gap with steel plate - a cut-up sheet steel weight from a freight car works well. Even though the stack of new magnets is of less area than the originals, you will be amazed at the improvement in performance.

I looked for my thread showing the procedure but couldn't find it - probably in with another, completely unrelated topic.
I did, however, find this remark which I made, which shows that these aren't your ordinary run-of-the-mill magnets:

"As for magnets, I just tested a rare earth magnet which easily picked up a 22 ounce mini-anvil. The magnet is 1" long and 3/16" in diameter. The same magnet will raise a steel bar 1"x1.5"x8" from a lying-flat position to standing-on-end, but won't quite lift it. Weight of the bar is 51 ounces."

Wayne

[cnrglen]

Thanks for your input Wayne,
Unfortunately this project has taken a tragic turn. On Saturday I met my friend for coffee and gave him the engine and decoders. An hour later he was in Michaels Craft store and had a cardiac arrest. He couldn't be revived and passed away. I may try to do the install myself but I'm not sure.

[cnrglen]

I went to coffee this morning with the rest of my local MRR club and got the engine back. I also have another modeller (whose sideline is electronic repairs) taking another look at adding the decoder. In the meantime I've built this for another modeller:

It's another old-timer 2-8-0 but I just built this one box stock. It took about 2 days to build it and work out any kinks or binds in the drivetrain. It was used when I got it but in pieces. It looks like someone had tried to assemble it and given up. It runs quite well considering it's 5 pole open frame motor.

Of course I couldn't resist comparing it to my modified unit.

Lowering to boiler height and changing the cab makes it look like a very different engine.

I haven't gotten to go-ahead to weather the SP unit yet. But I probably will do a bit, just to kill that plastic shine.

[cnrglen]

I got my engine back from getting the decoder installed:

We decided to go with a DZ-123 decoder for it's small size. As it turns out the motor only draws about 500ma and with no binds in the mechanism the current draw is well within the decoder's specs.

The only thing my decoder install guy said was the current coming through the drawbar was intermittent so I'll have to tighten up the connection somehow.

While I was shopping for some decent tender trucks I found this at a hobby shop.

At first I thought I could use the whole tender but it is a high-sided tender, probably a pennsy prototype so I'm not sure of it. The trucks though were pretty much what I was looking for.

On the other hand the Athearn Genesis tender looks more the part and is the same length as the Bowser. I may just use the athearn tender with the bowser underframe and trucks.

[doctorwayne]

If I'm not mistaken, Glen, those are Kiesel trucks, and were designed by W.F. Kiesel Jr., a mechanical engineer working for either Baldwin or the Pennsy. He also designed the tender, so using either the trucks or tender will tie it to the PRR...not necessarily a bad thing.

Wayne

[cnrglen]

Thanks Wayne. I know that they aren't the totally proper trucks for my N-4-a but they'll at least look the part. I think the actual trucks are Andrews with leaf springs so I at least got the leaf spring part.

[cnrglen]

I finished the engine detailing this evening.

I added the bell (Bachmann), handrails, number board (Cal scale), and headlight. I've left the whistle off to keep to brass colored while painting. The bell will be removed for painting as well.

I took the cab off so I could slide the handrails through the stantions from that side. That and it will come off for painting anyway.

I found that I couldn't get the handrails exactly prototypical in the front. They are supposed to come down to the pilot deck but that's not really possible when you have to remove the boiler from time to time. and I don't think I could make them look right anyway. I think I'll just clip the wire at the bottom of the stantions and be done with it.
I ended up using the MDC headlight setup but I sanded the numberboards off the side of the headlight for a more CNR look.
Next, the Tender!

[Schraddel]

... I found that I couldn't get the handrails exactly prototypical in the front. They are supposed to come down to the pilot deck but that's not really possible when you have to remove the boiler from time to time. and I don't think I could make them look right anyway. I think I'll just clip the wire at the bottom of the stantions and be done with it. ...

Glen,
drill two small bores into the pilot deck. The diameter a little bit larger than the wire you used to make the handrails. Into this bores the lower ends, make them a little longer than needed, will be threaded in; no glueing here. So the lower ends of the handrails are guided and fixed, but removing of the boilershell is easy possible; prototypical apperance not excluded ...


This is also such an case of handrails going down to the pilot deck.

Just my 2 €ents

Cheers Lutz

[doctorwayne]

I use the same procedure as Lutz, and the boilers are easily removed whenever necessary. You do need to place the removed boiler in a manner so that the extended portion of the handrails doesn't get damaged while you're working on the rest of the locomotive. I find that an Athearn Blue Box, or even a small block of wood works well to keep them from getting distorted: simply set the boiler crosswise on the box or wood with the front end handrails hanging free.
As you can see, many of my locomotives have such handrails:















It does help to prevent accidental bending of the front handrail extensions and also eases re-assembly of boiler and mechanism if you use sturdy wire rather than soft brass. I prefer .015" or .020" music wire, but phosphor bronze or half-hard brass wire will also work well.

Wayne

[nachoman]

Agree with Wayne here - use stiff music wire, drill holes in pilot to accommodate wire ends, fashion some kind of cradle to hold the boiler when it is removed, and it becomes a non-issue. I've got enough other piping and claptrap that hangs below my boilers that I have to be careful anyway when the boiler is removed.

You are doing a fantastic job on these

[cnrglen]

Okay, I did a bit of re-engineering:

I used the suggested procedure and I think it looks better now. I wasn't able to use the stand-offs on the boiler front but I might make marker light mounts out of those then.

I still have to solder the cross brace on the front and I noticed that I could use some filler where the steps attach to the boiler walkways.

[cnrglen]

I added the cross brace to the handrails:

It was a bit tricky. The solder wouldn't work with me unless I added some flux paste and I had to hold the one side down with some scotch tape while I tacked the first end down. But I do think it looks better than it did before. I also added some filler putty to the underside of the stairs.


Just in case any were wondering how I held the engine while soldering....

[cnrglen]

The engine is put away for a bit now while I concentrate on it's tender. I have made some good progress on that front:

I'm using an Athearn Genesis tender shell that I picked up cheap on Ebay. I like it's shape and level of detail. I know that the CN engines in the pictured had extensions on the coal bunker but I think I'll leave this one the way it is. I do like the looks of those Bowser trucks though.

I used the Bowser chassis mounted on some .040 styrene sheet. I had to shave the bolster down on the frame to lower it a bit so the coupler would sit at a good level. After that I then had to cut the mounting tabs off the frame so the trucks would swivel properly.

One thing I am going to change is the power pick up from the tender. As this is DCC and it needs a constant power pick-up I don't trust the drawbar to do that. So I'm going to wire a micro plug onto the brass strip on the tender instead.