How to close gap between passenger cars?

What diameter is your sharpest curve?  That will determine how close your cars can be.  If you have broad diameter curves, say, 0-120, you could run them prototypically close.  As the curves sharpen, the distance between the cars needs to increase.

One way would be to drill out the rivet holding the knuckle coupler and replace it with kadee couplers on the bar. By mounting it talgo style you will still be able to run fairly tight  curves though not as tight as you can now. Trying to retain the coupler but moving it closer to the truck would require modification of many of components.

Pete

Don,

Pete is 100% correct. If you still want to go ahead with it. If you can gain a look into the other magazine archives. Around this time last year they had a major "how to" article. I was amazed at how much work it involved.

If you plan to install diaphragms, you might not need or want to close the gap any further. If you do you might not have enough space for the diaphragms. Might want to get some diaphragms first and experiment. I also wanted to shorten the gap between some  Lionel aluminum cars but when I retrofitted diaphragms the gap was just enough for them.

I run an articulated coch with a full-width diaphragm.  It has roughly 1/8" more spacing than the scaled down real thing, and barely makes it around what you call O-148.

Glacier runner I did a brief tutorial in 3 rail scale forum on how to convert lionel to close coupled kadee equipped passenger cars. If you have questions email me. If you go to 3 rail scale it is on 2nd or 3rd page.

Ron

My MTH cars have a hard rubber diaphragm on each end. If there was a way to replace one of them with a very soft diaphragm, you could put magnets in a hard one & a soft one to have them connect. The hard diaphragm would keep the soft one from dropping into the coupler and the soft one would flex to follow the curves. When you are ready to put the cars away, just pop the magnets apart.

Does anyone already make this set up? 

Neat Idea!

I've modified the couplers on all of my Lionel streamliners as well as some other cars.  It does require modification of the coupler shank, but it is a pretty straightforward job.  I've attached a pdf of an article I posted several years ago about the procedure.  

I have 1 1/4 inch between the cars. I am going to buy the diaphragms first--who stocks the correct size?On these older cars will I have to glue the diaphragm to the one side? I am running on 042 curves now, but once my layout is done the sharpest curve will be 054! Lots of great ideals--thanks for all the help!! Don

At O54, I don't think you can have touching diaphragms.  At O108 (R54) you could.  I think you'll find the space is right once you add the diaphragms.  I have some MTH cars that I wouldn't want to move closer than stock when I run them on O54 as they'd hit and pull the car off of the track.

I agree, 054 is too tight to shorten the couplers by much. a lot of work for not much effect. Diaphragms are your best bet. They come up for sale on ebay from time to time.

I am able to negotiate 042 with diaphragms touching. These have plastic buffer plates though and are able to slide across each other. Might be a problem with rubber to rubber contact.

Pete

The soft diaphragm I picture would be almost latex balloon thin/flexible. The rubber wouldn't rub, they would stick together, and that soft flexible diaphragm would flex as needed, we are only talking 0.5" in most cases.

When this idea gets used, and it is mas produced and I am still a poor fella in NE Ohio...I will still be a poor fella in NE Ohio....

What we need is diaphragms that have a slightly rounded surface to them where the 2 diaphragms rub together.  I tried regular Kadee couplers on my 21" cars (fixed to underframe) and the edges of the striker plates caught on each other on 072 curves.  I had to use the new, longer Kadees.

This is how I mounted a kadee coupler to a Lionel passenger car. I did this to one end of a car to allow coupling to an engine that had been converted to close the gap. I have not decided yet if I will modify all the cars like this or maybe use Peter A's method. I can live with lobster claws but the gap, not so much.

While not a passenger cars, these B units have been close coupled using kadees. The kadees are mounted to the truck rather than the body which allows for negotiating tight radiuses and still very close coupling.

back to back 042 curves. Not possible with body mount couplers.

Pete