Hello all, I tried double heading a pair of bachmann engines this weekend with some difficulty. I have a bachmann gp40 and a sd40-2 both of which are all wheel drive. I do not use dcc, and I use bachmann ez track. I tried both ways but found having the faster train out front worked best for me. The problem I had was that when going through a switch when the first engine would encounter the curve of the switch, it would slow it down just enough that the second engine would push the lead engine and cause the rear of the lead engine to derail. Is there something I can do to correct or help this without switching to dcc to compensate for engine speed differences. Any help or advice would be great. If anything else is needed to help with this problem, let me know.
I frequently double, triple and quadruple my Bachmann engines using regular DC. I do not have a Bachmann SD40-2 but do have a GP40 that runs well with the other engines in my fleet. I use mostly #6 Atlas switches and have had no problems with the consists going through them. If the switch is less than a #6 the radius may be to tight for the equipment. I would check wheels, and switch with an NMRA gauge. Also follow the train as the lead unit may be derailing at another location and then getting caught up in the switch which may explain the loss of power and tendency for the trailing unit to shove the lead unit off the track.
Was it me, I would treat this as a “derails on turnout” problem rather than a double heading problem. Use your NMRA gauge to check the track gauge and the wing rail positions on the turnout[s]. Make sure the flangeways for the frog and the wingrails are deep enough to prevent the flanges touching bottom. File off any sharp bits on the points. Make sure the points throw all the way over and stay pressed up against the stock rails. Make sure you don’t have a kink where your flextrack (or SnapTrack) joins the turnout. Make sure that you are getting power to points and point rails. File off any roughness at rail joints.
Check the gauge on all wheels. Make sure the coupler gladhands are not hitting point rails. Make sure nothing else like truck covers is flying low and hitting on rails. Make sure both trucks swivel freely in both directions. Check to make sure that all eight wheels are picking up juice.
Double heading DC locomotives works unless the locomotives are vastly different in speed. Conventional wisdom is to place the faster locomotive in front, so it is pulling all the time. Locomotives should not slow down much going thru a turnout, unless something else is wrong.
I will check all of this. As long as I am not double heading, both engines will pull cars both ways through the switches time after time with no problem. I do have a gauge and will check them all. I have checked the swivel on the bottom of both engines and all appears to be right. Both engines are very low hours. Thanks for all of you all’s help
That’s a tight turnout for a bigger loco to negotiate so it doesn’t surprise me that the SD40-2 slows down going through it. I have two six axle Atlas locos (H24-66 and U30C) lashed together that do the same thing except they don’t derail due to their weight. Another two, an Atlas SD24 and a Bachmann GP38-2 handle it well also, but in that case the GP38 is the lighter of the two and is in the lead.
As pointed out in prior post the #4 is pushing the envelope a bit for an SD40-2 locomotive in your lash up. I should have asked before, how many #4 turnouts are on your layout and are you having trouble with just one or several? How did the inspection with the NMRA gauge go?
Daniel: Welcome to the world of model railroading.
You are finding what a lot of us have learned and that the largest radius turn or switch is always the best way to go if you are going to have 6 axle engines.
Maybe in a yard where only 4 axle switchers will go, #4 may be ok. Better for future use if using the Bachmann track is get only #6.
WHich versions of those Bachmann locos are they? re the couplers mounted to the body or to the trucks? If htey are mounted to the trucks, what’s probbaly happening is the one behind is pushing on the one in front which is skewing the truck sideways, makign it that much more likely to pick the point or climb the frog and derail. Does it go through by itself, or still derail?
Now you have an excuse to design and build a newer bigger better layout. Kato makes a better track than Bachmann, and gives you a way better variaty of turnouts.
Just a possibility but dirty wheels and track could cause the lead locomotive to stall going througth the switch and then be pushed by the second locomotive, causing it to derail. Try cleaning both the track and wheels with rubbing alcohol and see what happens.
Good suggestion. I hardly give dirty track a second thought anymore. I re-GLEAMed my layout after rebuilding it to the track plan I’m using now and haven’t had to as much as put a cloth to the rails since. If you don’t mind using a little elbow grease the GLEAM method is the way to go.