Atlas 2rail 33k tank car couplers..which ones to use?

If you take the next larger inch drill bit and make the holes bigger, you can get the screws thru the KD plastic box and into the stock Atlas holes. I try and enlarge and oblong the holes towards the middle of the box, If I remember correctly?

 I would use the modern 74x long shank center set couplers myself. It helps longer cars go in and out of my yard switches and S curves better.

http://kadee.com/htmbord/page746.htm

I just compared the two couplers(spares from prior surgery)..holes off by about .010"

Will the existing screws holding the Atlas couplers work with the 746's once i stretch the holes?

I'm going by memory here, and that's dangerous.

The tank cars I have done needed new screws. I think the Atlas has short screws that go thru just the one thickness of the plastic box? I can't remember.

 I have a couple of cars with broken stock couplers. I'll tear into one and see. It may not be until tomorrow. I'm cutting holes in cabinets for G scale! (another post).

If you use 2mm screws, the Kadee box will mount on the Atlas holes. The catch is that the Kadee coupler will sit high as the top of the Atlas draft box is thicker and the front of the draft box sticks out from the end sill of the car (the front of the Atlas box is also thicker). On level track, that isn't much of a problem, though. The Atlas cars actually look like they sit a bit high (the 2-rail cars are the same ride height as the 3-rail cars).

There's a Kadee 700 series that is "over-set" (coupler head sits lower than the center of the shank) which would be at about the right height, but it looks weird. It's what I call the last resort before altering the car frame.

Studying the Atlas trucks, if you remove the cross-bar, you can shave down the "tube" in the bolster of the truck to drop the ride height of the car. The truck also equalizes slightly which improves operation on slightly uneven track.

Nice idea Matt. I hate to use offset couplers. In G scale, they will fail on a heavy train dipping at the end and uncoupling. It would be much better to just use a shim than the offset. Lowering the car would be ideal to help all issues.

 I wonder if the new series 2 rail trucks are the same height? Probably are when I think, as I type this. Duh.

I don't see a long overset on Kadees website. Can i use a 746 with a spacer? My LHS carries almost all scale Kadee couplers so i will grab some medium "overs" as well. I have one radius that could cause bind.

  Now that i think about it if all 9 of my 33k'ers have 746's i would have to modify just the 2 ends..i need a beer

Oopps..just saw Joes post on spacers

Hibar..i have the 2mm tap but the machine screws at LHS may be scarce.

You will have to go on the web for these,however they are very reasonable [compared to LHS] and you can get various lengths,head style[slotted,phillips etc] and metric small drill sets, bottom taps also can be helpful.Micro Mark here in NJ is a good source for this stuff for hobbyists but just googling the 2mm screws will get you the best deals.Just Saying!

Willygee;

Are you interested in couplers that work & look 100% like the Prototype that can be uncoupled with cut levers or a top operated magnet that will release the pin holding the knuckle closed? If so,Protocraft has just come out with a new E coupler that works this way. I'm not sure how they'll fit an Atlas car am trying to find out more about that along the way here. Price is $59.99 for 5pr which includes draft boxes.

Hope this helps.

Al Hummel

The long-shank couplers are actually a higher risk if there's plastic involved. Had to replace the couplers on some Atlas 89-foot flats as the Atlas shank was plastic and would shift up or down under heavy load. Replaced them with Kadee's which are metal and used metal draft boxes. Was able to use the Atlas spacer plate with new holes drilled to properly position the Kadee box.

Well, this might save me some. I already put them on a few cars though.

Long trains in G scale seem to make the laws of physics appear. If something can fail, it will.

 I haven't had much problems in O scale in my basement yet. I bought too many engines so the cars I have, don't tax them very much in big consists.

 I have noticed that the older Atlas couplers will either come uncoupled, or break. I haven't replaced very many of them yet. I put up with it for a few years now. With pushers on a train, nothing fails.