OK, I need some help with this item! I’ve been working on some yellow box Atlas and Rocco SD9 engines. Several of the truck’s gear tower plastic spines, which hold them in place on the chassis, are broken. It’s difficult to get the trucks off, let alone put them back on. I can’t do it without breaking more of the plastic spines.
What’s the secret? Or did I even make sense?
Not really. No, just kidding. Is this HO or N? And I didn’t think Atlas made an SD9. They did make Atlas/Roco SD24 and SD35 models. Some of the instruction sheets for these may be found here: http://www.atlasrr.com/hoparts.htm
http://www.atlasrr.com/pdf/HO%20EMD%20SD24-35%20LOCO%20A.pdf
http://www.atlasrr.com/pdf/HO%20EMD%20SD24-35%20LOCO%20b.pdf
http://www.atlasrr.com/pdf/HO%20SD24%20&%20SD35%20TRUCK%20A.pdf
Any of these look like what you have?
Maxman,
You’re right, they aren’t SD-9’s! [:I] The last PDF file is the exact match for the trucks. The problem I’m having is not the assembly, but getting them back on the chassis without breaking the spines. They are a nightmare!
Thanks for posting the great info! [tup]
I’m still not sure what you mean by spines. Are you talking about those two arms that look like they run horizontally in the area of the clamp? I don’t have the model in front of me, but what will happen if you don’t install the clamp until after you have the truck assembly in place?
I think you could call them tabs, hooks, or ribs, but they are a pain because you have to bend them enough for the truck to clear the kingpin. I think the trick is to bend them only until the truck comes off the pin and no more. At least Athearn molded theirs as part of the worm cover, which makes dropping the trucks a lot easier.
Yep, that’s what I’m talking about. Unfortunately, I can’t get an assembled truck back in the chassis without seriously risking breaking the horizontal arms. I can get an unassembled truck in place and the press it back together, but then I can’t get the top clip in place. The clip allows the chassis nub to ride and pivot on the truck. It’s a separate piece. [banghead]
I see what you mean now. Did you actually break any of those arms, or are you just concerned that you will?
Two of the four engines had already broken. Forcing the arms could break the replacements. The plastic is not as malleable as an Athearn model. I assumed there was some secret push and twist motion, magical word, or rare pixie dust which would induce the trucks to assume their rightful position.
I think your best chance of success would be to try to push the assembly on with as little twisting motion as possible. So far as magical words go, well, this is a family-oriented forum.
I knew exactly what you meant by the post, but don’t remember that ever being an issue with the units I’ve worked on. I seem to recall they just slid over (applying most force horizontally rather than vertically) and snapped on. Which direction do you have the tabs pointing? I believe they should be pointing toward the center. In the past, has some plastic eating lubricant been applied to them that has made them brittle?
Which direction are the arms pointing? When assembled they are usually horizontal just to the left or right of where they need to be. Sideways pressure must be applied to get them over the higher center area of the chassis bar. Likewise, they have to bend upward at the same time in order for the bottom of the truck to clear and then pop into the metal nub underneath.
I think I’ll post some pictures this afternoon.
Thanks for that link. I found the parts and assembly sheets for my two 70’s era Atlas/Roco GP40’s.
You’re welcome. Those models also may be found here: http://hoseeker.org/assemblyexplosionAtlas/Assembly%20Explosions%20Atlas%20EMD%20GP-38%2040%20pg1.jpg
Here’s a repair I did on a Roco FA with a broken truck retainer. I cut the end of a short section of brass square tubing open so that it fit over the remains of the retainer, then glued it in place with CA and baking soda. It’s best to roughen the plastic up with sandpaper first for a better grip.
I’m working on an SD35 now that already has one arm broken off of each truck due to earlier removals.
The engine is fine as the arms just keep the trucks from dropping off the loco when it gets lifted off the track.
As long as the truck is pivoting on the kingpin, it’ll work just fine
I’d kind of like to get replacement parts, but it’s not essential
With only one arm on each truck, they’re much easier to remove and replace
