Atlas SD50 Conversion.

[oakcreekco]

Just an "if", but if you were going to modify a Kato Dash9 mechanism to accept an Atlas SD50 body, would you be happy enough with the SD40/45 sideframes??????

Any and all opinions, comments, tips, suggestions would be appreciated. Looking at DRGW which were built pretty close to the CR units.

Initial "evaluation" looks like the Dash9 truck spacing is very close. SD40-2 trucks won't work in a -9 frame, and SD40-2 truck spacing is too short, along with the SD40/45's spacing.

Yes, could be some work, and some frame "milling" will be needed to pull this off.

You can call me crazy, and that's fine. Just looking for some input.

[Ed Kapuscinski]

Let me know how it goes, because the Flexicoils are JUST what I'd need.

[Robbman]

Will the SD40-2 siderames fit on the C44-9W gear towers? Both would have to be older runs, and it's been like 6 years since I looked at them, biut I could have sworn there was some interchangability there...

[Ryan87]

here's an idea...

Why not just sand down the detail on the HTC sideframes and glue Flexcoil sideframes on...
the off axle is not that noticeable... 

[Robbman]

He's not going for a Conrail SD50...

[oakcreekco]

Robbman, the SD40-2 trucks (early runs) are completely different gear towers and sideframe designs compared to the SD40/45/-9's. Dang it anyways.

I suppose one could try and "stretch" a SD40-2 mechanism, but that would be a lot of work. Initial "eyeballing" looked like the -9 would be the best bet for the frame. A tempting thought for an IM Tunnel Motor conversion.

[Chris333]

Is all this because of the Atlas SD50 trucks? I don't pay much attention, but I though there was a fix for these to keep the center wheel from bouncing.

[oakcreekco]

Yep. There's a "fix", but more of a temporary band-aid IMO. These trucks and frames aren't "Atlas at its' best".

I've spent way too much time "fooling around" with these, and I've had enough.

[Ryan87]

He's not going for a Conrail SD50...

Oops.. the first post mentioned using the SD40/45 sideframes my bad (dang twice today  )

Big problem I would see is the Kato frame would be too wide for an atlas shell...

[ednadolski]

I though there was a fix for these to keep the center wheel from bouncing.

What is the fix?  (I see this on the SD60 too.)

thanks,
Ed

[Chris333]

Sorry for bringing it up without knowing...

I thought there was a several page thread on Atlas recently, but I can't find it. I don't own any of the SD50/60's, but I hear about the problems all the time.

Anyone else know how to fix 'em?

[u18b]

Chris,

The thread is still available.  It is encyclopedic and would be interesting to some- even if pretty long.  It's heavy on loco design theory.

http://forum.atlasrr.com/forum/topic.asp?ARCHIVE=true&TOPIC_ID=42265


The good stuff you want starts on page 14.
http://forum.atlasrr.com/forum/topic.asp?ARCHIVE=true&TOPIC_ID=42265&whichpage=14


There is a link to an extra goodie at the end of page 15.

Ron

[Chris333]

Figures, I was searching "wheel hop" not "axle hop".  :-\

[Mark5]

Figures, I was searching "wheel hop" not "axle hop".  :-\

So the axles hop eh? Video please!

[u18b]

This is all a euphemism.

The trucks don't "hop".  The axles don't "hop".  The center axle simply lifts off the rail about 1 millimeter and then drops back down again.  You can only see it on a poor running "tap dancer" that is running very slowly.

You would have to have a camera with a very VERY close lens in order to even see this.

The link above document it and how to fix it.