DDT

[orangeman]

I bought a Bachmann DDT switcher by mistake. Can someone please tell me what DDT means. And can it be converted to DCC?  thanks.

[rich1998]

What is a DDT switcher? More info please.

Lex

[orangeman]

HO SCALE TRAINS ENGINE SANTA FE DDT SWITCHER LOCOMOTIVE     

HO SCALE TRAINS ENGINE SANTA FE DDT SWITCHER LOCOMOTIVE
Model #M96670

HO scale Burlington Northern DDT Plymouth Industrial switcher by Model Power. Don't let the size fool you, there little switchers pack a punch! Includes knuckle couplers, working headlamp and manufacturers warranty.

I'd put a picture here but can't figure out how to do it.

[rich1998]

I have put a small decoder in a older Pymouth loco. Red wire to one rail pickup, black wire to the other rail pickup. Orange and grey wires to motor terminals. White and yellow wires to one headlight bulb lead, the blue wire to the other headlight lead.
Standard NMRA wiring practice.
I had to disconnect the motor terminals from the side frames.

Lex

[pdlethbridge]

in reply to orangeman's question about DDT, please visit this link at 'railroading in the northeast'
http://www.northeast.railfan.net/diesel123.html

[CNE Runner]

Orangeman - I thought you made up that Plymouth DDT as I had never heard of this model. Please accept my apologies. The Plymouth Locomotive Works made a seemingly endless series of small, industrial switchers (beginning in 1927); so keeping track of all the models is difficult. You can see a picture of the prototype DDT at http://www.northeast.railfan.net/images/plymouth4.jpg and you can probably see that Model Power did a reasonably good job of copying this engine.

I have the Bachmann MDT (which is misnamed because it is a WDT) and have had good success with this little hauler. I lubricated the gear train, put graphite powder on the axle-to-frame contact points, and keep the wheels squeaky clean. Keep in mind the WDT is a 3-axle locomotive and picks up power from all 3 axles.

Your Model Power DDT is a 2 axle model and may give you some problems with electrical power pickup. The way around this is to use turnouts with live frogs (a.k.a. Peco Electrofrog versions). The reason for this is the shorter distance between the wheels necessitates almost continuous electrical contact...Electrofrog units come the closest to providing that option.

Trust me on the advice I give above. On the Monks' Island Railway I foolishly installed a Peco Insufrog double-slip turnout and a Insufrog crossing (all other turnouts are Electrofrog). Guess where any stalling occurs? Right....on the Insufrog units. At this late date all I can say is; "Never again!"

If you experience any stalling, and don't want to change turnouts, the Bachmann WDT (or as advertised MDT) is a fairly good runner - and not as prone to stalling. I have to admit I do like the look of that DDT.

Regards,
Ray

'P' it looks like you beat me to the punch on that website reference.

[Joe323]

Forgive my Ignorance What does DDT WDT NDT etc stand for?

[pdlethbridge]

I think that would be a model designator, like SD, GP, BL, What each letter stands for I'm not sure as each loco company had its own way of designating their engines. GP stood for general purpose and BL was branch line. SD, I don't know. 
Ray, is there some way to put a capacitor in to hold some power for the engine over the dead spots, like the units on the sunami sound decoders. They call it a keep alive cap.

[CNE Runner]

Joe - I haven't a clue what (or if) the letters stood for anything other than model designations. Bachmann bills their little Plymouth switcher as a MDT which was a 2 axle model whilst the WDT was Plymouth's only 3 axle engine. Oh well, it would probably cost too much to change all the advertising...and those hundreds of boxes (besides I am just thrilled that Bachmann and Model Power keep producing small industrial diesel/gasoline switchers).

Pdlethbridge: Boy, don't I wish something like your capacitor idea could be retrofitted...'would solve a multitude of problems wouldn't it? I communicate with another micro/mini layout affectionado in Germany. He runs a couple of old Penn Line Davenports and swears by Peco Electrofrog track units as well as keeping everything 'surgically' clean (his words).

The Bachmann MDT/WDT can be made into a decent runner; but could use some better gearing (as in lower). It is almost impossible to keep the darn thing moving at ultra slow speeds (as when coupling). I think Lexon had an MDT/WDT converted to DCC.

Ray

[mf5117]

we did my mdt plymoth .dc to dcc  no problems at all .dont forget to insulate the motor from the frame . even gotta beacon light on him . i have never asked but would it be classified as a 40 tonner or no .just wondering ....

[mf5117]

and we used a 1006 tcs m1 n scale decoder

[on30gn15]

i have never asked but would it be classified as a 40 tonner or no .just wondering ....

Hey there;
Looking at pages 133 and 134 in Jay Reed's book Critters Dinkys and Centercabs it says

"WDT's were very similar to concurrent MDT's except for having 6-wheels and being 22" longer"

Captions under two photos of WDT on p.134 give

(40 ton)

On page 98 it gives some explanation of Plymouth's "alphabet soup" identification system.
And notes that there were 6-wheel WL with mechanical transmission while WDT had a hydraulic torque converter transmission.

[Jim Banner]

PD, according to one steam affectionado of my acquaintance, SD stands for "Stinkin' Diesel."  But others have told me it stands for "Special Duty."  I believe the 'special duty' may be that the weight is spread over six axles instead of four, allowing them to operate on lighter rail than the equivalent GP.

Jim

[rich1998]

I think that would be a model designator, like SD, GP, BL, What each letter stands for I'm not sure as each loco company had its own way of designating their engines. GP stood for general purpose and BL was branch line. SD, I don't know. 
Ray, is there some way to put a capacitor in to hold some power for the engine over the dead spots, like the units on the sunami sound decoders. They call it a keep alive cap.

Keep alive info. You need some room.

http://www.members.optusnet.com.au/mainnorth/alive.htm

You need to put a proper size capacitor on the output of the full wave bridge rectifier that every decoder has. Also, need the diode and 100 ohm resistor for the stay alive to work properly. All the info is in the link.
Try this with a N scale decoder. Get out your magnifying glass.

Lex

[CNE Runner]

On30Gn15 - Thanks for the information. I was under the impression that all Plymouths were hydrostatic equipped. I can just see the runner pushing in the clutch and shifting his WL into road gear (I would vote for a lit skull head shift knob). I learned another new fact.

Mf5117 - I will keep the DCC conversion information on file...just in case I decide to go DCC on my micro/mini layouts. Frankly, with only one locomotive it doesn't justify the expense - but you never know.

Lex, I am assuming you were referring to DCC? I wonder if some sort of a capacitor could be used with DC. If that were possible...where the heck would you find the room in a MDT/WDT?

Ray