Rapido Dash 8-40CM Dofasco Trucks - use for MK5000C?

[ryan_wilkerson]

With all the 3D printing going on, I've been thinking about the feasibility of a Morris Knudsen MK5000C locomotive. Researching the trucks it looks like the Dofasco trucks on the new Rapido Dash 8-40CM are a match. I haven't looked further into the chassis length to see if it's close to the MK5000C spacing, it's probably different. If there's a Kato or Atlas mechanism that would fit the trucks (no idea if the design is compatible), it would be interesting to test them.
Does Rapido sell trucks separately?

Photo of SP 502 by James Belmont
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[screeh]

A MK5000C would be a fun project!

Have you considered the Dofasco truck conversion kit available from Briggs Models?
http://www.briggsmodels.ca/order.php#!/N-Scale-Dofasco-truck-conversion-kit/p/94872904/category=0

[ryan_wilkerson]

Definitely a unique locomotive from the mid 1990s!
I didn't know about the Briggs truck conversion, thank you.

The length of the MK5000C is 71 ft 2 in.
The length of an EMD SD50 is 71 ft 2 in.

So the Briggs conversion uses the Atlas C630 trucks.
Truck spacing is probably a long shot... C630 trucks on an SD50? Both are Atlas parts so hopefully they physically fit.

A MK5000C would be a fun project!

Have you considered the Dofasco truck conversion kit available from Briggs Models?
http://www.briggsmodels.ca/order.php#!/N-Scale-Dofasco-truck-conversion-kit/p/94872904/category=0

[craigolio1]

Briggs did the 8-40cm as well. The kit came with new gearboxes and side frames, designed to be used in a Kato early SD40-2 chassis.  I believe they are still available.  You should contact him and see if the trucks could be sold separately.

[ryan_wilkerson]

Good to have that option as well. I just started thinking about this so I'll need to do more research to see what mechanism might work.

[Wolf N Works]

I have been wanting to do this for some time just never found any drawings with measurements so I could try

[ryan_wilkerson]

I’ll do some research next week to see if there are any drawings available!
Ryan

[craigolio1]

Just sides won’t do if you plan to print these. They have a shorter wheelbase than other available trucks. The Briggs trucks include the gear box which is designed to use the Kato gears. That said it’s made to mate with the SD40-2 chassis and I don’t know if that chassis will work with this loco.

[jjb62556]

I used the gears from a Atlas C630 to convert my trucks.

[ryan_wilkerson]

The shell itself will be tough enough so I'm not looking to print trucks, I want something already available. Same with the mechanism.
Thanks for the info on the Briggs trucks using the Kato gears to work with the SD40-2. Will need to continue research on dimensions.

Just sides won’t do if you plan to print these. They have a shorter wheelbase than other available trucks. The Briggs trucks include the gear box which is designed to use the Kato gears. That said it’s made to mate with the SD40-2 chassis and I don’t know if that chassis will work with this loco.

[jjb62556]

Briggs Dofasco truck instruction sheet says to use the gears out of the C628/630 trucks not Kato SD40-2. just look them up on his site.

[JanesCustomTrain]

Briggs Dofasco truck instruction sheet says to use the gears out of the C628/630 trucks not Kato SD40-2. just look them up on his site.

There are two different Dofasco trucks from Briggs. The ones for the Atlas C630 chassis and the ones included in the Dash 8-40CM kit for the Kato SD40-2 chassis.

Jane

[craigolio1]

There are two different Dofasco trucks from Briggs. The ones for the Atlas C630 chassis and the ones included in the Dash 8-40CM kit for the Kato SD40-2 chassis.

Jane

Correct. The only trucks listed on the site are the Doffasco trucks for the M630/W. They use the gears from the donor chassis used on those models.

The 8-40CM Doffasco trucks came in the kit and are not available as a separate item on the site. Unfortunately there are no N scale models that have the correct wheel spacing at this time, hence the need for a new truck in the kit.

[Vince P]

Considering these MK5000 engines are upgraded SD50's produced my MK when they were around.

[ryan_wilkerson]

The MK5000C were designed as new units even though the longhood has some resemblance to the EMD SD50. Later in their life they were retofitted with diesel engines found in EMD 50 series locomotives. Here's the info from Wiki:

"In 2001 the Utah Railway tested and later acquired all 6 units from Wabtec, the owner of MotivePower Industries. However, after one year of operation, all units were out of service due to problems with the main bearings on the Caterpillar 3612 diesel engine and Kato main alternator. The units were returned to Wabtec and had the CAT 3612 and Kato main alternator removed and replaced with an EMD AR11 main alternator. At the same time, the engine blocks were replaced by EMD 3500 Horsepower 16-645F3B diesel engines from 5 retired Union Pacific EMD SD50 and 1 retired Union Pacific EMD GP50 locomotives. The 6 units were reclassed with the designation MK50-3 and are now back in service with the Utah Railway."
From https://en.wikipedia.org/wiki/MK5000C

-Ryan

Considering these MK5000 engines are upgraded SD50's produced my MK when they were around.