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Athearn RDCs

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Athearn RDCs
Posted by John-NYBW on Thursday, March 4, 2021 9:55 AM

Many years ago I bought a pair of these at a flea market intending to use them on my old DC layout. It was a powered combine and an unpowered coach. As it turned out, I dismantled that layout and moved to my present home about 20 years ago before ever putting these into use. I had almost forgotten about them until I cleaned house and started selling off all the old museum pieces. I decided I could put these to use on my present DCC layout just by adding a decoder to the powered unit. What I discovered when I opened it up was it appears to be a rubber band drive. The rubber bands were not included and if they were, they probably would have dried out by now anyway. I'm trying to figure out what kind and size of rubber band to use. A long time ago we had one of those Athearn rubber band drive switchers and as I recall it used the wide rubber bands. I have a couple locos, including a Walthers doodlebug, which uses a small thin black band and I bought a package of similar ones on Amazon (1000 to a pack) as a replacement for one that had gone bad. Also, should I attach a rubber band to each axle (4 in all) or just one at each end. Any other advice for these is also appreciated.

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Posted by NVSRR on Thursday, March 4, 2021 10:31 AM

I have two of those.    All four axles have rubber bands on them.    
shane

A pessimist sees a dark tunnel

An optimist sees the light at the end of the tunnel

A realist sees a frieght train

An engineer sees three idiots standing on the tracks stairing blankly in space

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Posted by Lakeshore Sub on Thursday, March 4, 2021 10:36 AM

Hi John.

You would put a rubber band on each axle that has a spot for it.  The rubber bands also have to all be twisted onto the drive shaft in the same direction or they will fight against each other.

Had an F7 with the rubber band drive that ran well but you will find that most starts and stop are somewhat abrupt compared to motor/gear combinations.

Scott Sonntag

 

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Posted by John-NYBW on Thursday, March 4, 2021 11:04 AM

Lakeshore Sub

Hi John.

You would put a rubber band on each axle that has a spot for it.  The rubber bands also have to all be twisted onto the drive shaft in the same direction or they will fight against each other.

Had an F7 with the rubber band drive that ran well but you will find that most starts and stop are somewhat abrupt compared to motor/gear combinations.

Scott Sonntag

 

 

That's the way I remember that rubber band drive Athearn switcher. It ran like a slot car but when you shut off the throttle, it stopped right now. Same with the starts. It would go from 0 to 60, scale mph of course.

I did a little more research and see that they sell bands specifically for the Athearn RDC, Hustler, etc. They look like the same ones I got in that package of 1000. I'm going to see if they work. It looks like you have to disassemble the truck to put the bands on the axles. It doesn't look like they just pop out. Is that the case?

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Posted by ATLANTIC CENTRAL on Thursday, March 4, 2021 11:08 AM

Yes, the trucks are held together with screws, easy to disassemble and reassemble.

I have six of them I converted to gear drive with a kit that was available years ago.

I can post some photos when I get home.

Sheldon

    

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Posted by John-NYBW on Thursday, March 4, 2021 11:37 AM

There's a washer for the screw that holds the truck to the frame and when I removed the screw, that washer crumbled. Looks like it was made of plastic that became brittle over the years. I'll have to find a suitable replacement. Looks like the KD washers might be a good substitute if I can find any in the small parts cabinet. After taking it apart. 

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Posted by SeeYou190 on Thursday, March 4, 2021 11:38 AM

I have three of the Athearn RDC cars.

One coach will have a full interior, and I have a Northwest Short Line underfloor power truck for that model.

The other two will operate as a "set" with the red combine power unit in front. This one will have a power truck from an Athearn switcher in the front position and a Mabuchi motor in the baggage section.

The Ernst gear drive kit that Sheldon mentioned is a great solution, but they go for over $50.00 if you can find one, and they occupy the interior if that is important to you.

-Kevin

Living the dream.

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Posted by MisterBeasley on Thursday, March 4, 2021 12:20 PM

You might get better performance if you look up the Vhigh CV and greatly reduce it.  This will give you better control of speed, reduce jackrabbit starts and keep the cars from going to warp speed.

My old trains of that era had similar Athearn motors.  You might want to consider replacing those, too.

If those "washers" you've described are like the ones in my old Athearns, they are necessary to keep the left and right sides of the trucks electrically isolated.  They are a plastic tube with one end enlarged.  It's not a standard item.  A Kadee washer might work but you would need a nylon screw to maintain isolation.

It takes an iron man to play with a toy iron horse. 

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Posted by xdford on Thursday, March 4, 2021 3:48 PM

I used an Athearn switcher truck as a replacement for the drive and put a can motor to drive it.  The bracket was easily made and with the newer trucks you could cut the sideframes from the Budd and mount them on the power truck. One power truck is powerfull enough for three or four cars on my admittedly level layout. The 40" wheels are not noticeable from the side.  I did substitute smaller wheels but clearances for turnout rails were a bit tight!  The Canon motor makes it an excellent runner

PM me if you would like a photo!

Cheers from Australia

Trevor

Cheer

 

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Posted by John-NYBW on Thursday, March 4, 2021 4:07 PM

MisterBeasley

You might get better performance if you look up the Vhigh CV and greatly reduce it.  This will give you better control of speed, reduce jackrabbit starts and keep the cars from going to warp speed.

My old trains of that era had similar Athearn motors.  You might want to consider replacing those, too.

If those "washers" you've described are like the ones in my old Athearns, they are necessary to keep the left and right sides of the trucks electrically isolated.  They are a plastic tube with one end enlarged.  It's not a standard item.  A Kadee washer might work but you would need a nylon screw to maintain isolation.

 

I carefully removed the mounting screw from the other truck and it is indeed a plastic washer, roughly 1/16" thick. I also noticed the screw head was slightly larger than the first one I removed so one of the these is apparently a substitute. Maybe thats why the other washer broke apart when I removed the screw. If it had been over tightend with a smaller screw head, it might have cracked that washer/sleeve. 

The screws themselves touch metal on the frame so apparently what you call a sleeve and I am calling a washer insulated that screw from the truck but not the frame. Before doing anything with the trucks I was able to get the motor to run on my DCC layout using address 0000. Now that I see what the washer is doing, I don't think the KD washer will suffice for insulation. I might have to fabricate one with the end of a styrene tube. I just need to figure out what size I need. Maybe I'll get luck and find one in the styrene drawer. 

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Posted by Darth Santa Fe on Thursday, March 4, 2021 5:45 PM

Athearn still makes the rubber bands for these if you want the official parts.  Here's a pretty good deal: https://www.ebay.com/itm/Athearn-HO-Parts-Lot-of-24-Drive-Bands-Rubber-Bands-for-Hi-F-Locomotives-Hustler/164112303492

I've heard hairbands and certain sizes of O rings also work well.  I ended up using the Ernst gear kit on mine though, mostly because the rubber bands combined with the tube axles were a larger diameter than the wheels themselves and would ride up on the grade crossing/rerailer on my layout!

_________________________________________________________________

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Posted by ATLANTIC CENTRAL on Thursday, March 4, 2021 6:36 PM

Athearn RDC with Ernst gearing and replacement motor:

 

 

 

Sheldon

    

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Posted by mbinsewi on Thursday, March 4, 2021 9:17 PM

Cool.  Who makes the powered truck? 

I mean, I have a box of athearn powered trucks from GP's and Sd's, but what did you use?

Mike.

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Posted by ATLANTIC CENTRAL on Thursday, March 4, 2021 9:49 PM

mbinsewi

Cool.  Who makes the powered truck? 

I mean, I have a box of athearn powered trucks from GP's and Sd's, but what did you use?

Mike.

 

Are you asking me? That is a kit made by a company called Ernst, it is no longer made, but they do show up NOS from time to time at train shows or on Ebay.

It uses the original Athearn rubber band drive truck and wheels (or replacement wheels from NWSL), it just replaces the big drum axles with gears and has the gear tower parts.

The motors I used were from another company no longer in business, it was a drop in replacment for most all Athearn products. It has a mount that goes right into the Athearn rubber motor mounts.

Here is one with an RDC to convert:

https://www.ebay.com/itm/Athearn-2175-RDC-3-with-Ernst-Super-Gear-Set-Undecorated-NOS-HO-Blue-Box/265069985604?hash=item3db766ff44:g:QZEAAOSwu51gOqPL

Sheldon

    

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Posted by mbinsewi on Friday, March 5, 2021 8:30 AM

Thanks Sheldon, yup, asking you.

I remember the Helix Humper motors.

Thanks for the info.

Mike.

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Posted by John-NYBW on Friday, March 5, 2021 11:23 AM

Darth Santa Fe

Athearn still makes the rubber bands for these if you want the official parts.  Here's a pretty good deal: https://www.ebay.com/itm/Athearn-HO-Parts-Lot-of-24-Drive-Bands-Rubber-Bands-for-Hi-F-Locomotives-Hustler/164112303492

I've heard hairbands and certain sizes of O rings also work well.  I ended up using the Ernst gear kit on mine though, mostly because the rubber bands combined with the tube axles were a larger diameter than the wheels themselves and would ride up on the grade crossing/rerailer on my layout!

 

The hairbands are what I ordered in a package of 1000 from Amazon. Just eyeballing it from the online pictures, they look like they are the same as the Athearn bands and much cheaper per item.

I don't think I'll go for a conversion, even if I could find a kit. These RDCs were just sitting in storage for decades and I thought they might make an interesting addition to the layout without having to spend a lot of time or money. Right now the problem is one of the insulating parts broke apart when I disassembled the trucks and I have to fabricate a replacement, probably from tube styrene. Then it's just a matter of adding a cheap decoder and I've got a new two car train for the layout. 

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