Bachmann Digital Commander and Kadee

[atari]

I have two Bachmann trainsets: The Bachmann Digital Commander (http://www.bachmanntrains.com/home-usa/products.php?act=viewProd&productId=1532) and the Bachmann Iron King (http://www.amazon.com/Bachmann-Iron-Scale-Electric-Train/dp/B0046MMI3A).

When we connect the diesels as a consist, they disconnect themselves on on the decline of our bridge set. I've read enough on this site to know Kadee couplers will be recommended.

My first question is which couplers do we need for the diesels.

My second question is, will the Kadee couplers that we install on the diesels work with the rest of the cars original couplers or do we need to change the couplers on all of the cars and which ones would we need?

I really like the idea of pulling a lot of cars (12-15) if that makes a difference.

Thanks,

[ACY]

148's are the best drop in replacement for Bachmann, they are available in bulk. If you think 12-15 cars is long, last month at my local club I was pulling around 200 NMRA weighted cars with 8 Atlas H15/16-44s, unfortunately I had to sell 2 of them because I was low on cash for rent. Got my paycheck the week after my rent was due 

[OldTimer]

I suspect that the uncoupling problem is due to abrupt vertical curves on your bridge set.  No coupler is going to compensate for uneven track.  Another possibility is that the engines are running down hill at uneven speeds and creating enough slack and misalignment that the couplers can work loose.  Having said that, Kadee has an extensive web site.  Look here:

http://www.kadee.com/index.shtml

On the site you'll find a conversion chart to help you pick the right model of Kadee coupler for your application.  While you're at it, buy a coupler height gauge (Kadee part # 205).  Hope this helps.
OldTimer

[mabloodhound]

I believe the Kadee #148 whisker couplers will drop right in and should be compatible with the Bachmann couplers.   Check the Kadee web site and their list of compatibles.  
The whisker is the newer replacement for the #5, but easier to install.

[Stephen D. Richards]

atari,
   #148 Kadee's are a perfect replacement for EZ Mates.  However, on a 15 to twenty car train, I think maybe Oldtimer is correct!  It may be that your locos/rolling stock are "bending" on the change in grade and uncoupling themselves.  If that is the case use a good coupler height gauge on your locos and rolling stock and then watch the rail very carefully where the locos uncouple.  you may have to lengthen and change the grade a bit to keep them coupled.  Hope that helps,    Stephen