I have some questions regarding the P2K locos I have:
How low of a radius can a P2K SD7/9, GP7/9, and GP30 take? I know I can go down to 18, but will it go down to 15? I ask because I’m planning a shelf layout, and wonder if I could use theses small of a radius in a hidden loop (like in a tunnel for instance)to just run trains in circles.
Will a frame from a P2K GP7-20 work for a P2K GP30? I have the 9 and the 30, but never tried it, and they are packed up for a while.
Does anyone have a frame that will work for a P2K GP30 (or a GP7-20 if they fit) that they don’t use? (I’ve heard of people replacing the ones from the GP30s with Athearn or Kato Drives; figured someone here might have done that and have the original laying around somewhere)
I know for a fact that the GP30 will take 18" radius curves and #4 turnouts like a duck takes to water. A friend of mine has what I think is a P2K GP7/9 and it takes tight curves as well.
The GP’s, with their 4 wheel trucks, should take the 15", aas long as the trucks can swivel that far without hitting frame/steps/etc. The SD’s have 6 wheel trucks and sometomes want to pick #6 switches, so I wouldn’t try them on less than 18 or 20" radius. As TA462 suggested, try them on a piece of flex track.[:)]
The P2K GP7/9/30 all have the same wheel base, the fuel tank is different on the GP30. They will run on 18" radius curves, but you may have problems when coupled to long freight cars. I suspect you might be able to get down to 15" radius, but only pulling 40’ freight cars.
The P2K SD7/9 will get around a 18" radius curve, but they WILL have problems with some freight cars, and coupling on a curve is that sharp does not work. I had a ‘house’ track with an 18" radius curve and the SD7’s keept pulling cars off the track when switching. My feeling is 15" radius is just asking for trouble.
As far as testing. use a yardstick to make a cheap compass and layout a 15" radius curve centerline. Use an old section of flex track to test with(yes it is the centerline of the track). Or buy some 15" radius snap track to test with.
Your PK2 SD 7/9 will not work on a small radius, particullarly through turnouts becuse the trucks are too long.
I don’t understand why you wnat to change out your PK2 locomotive frames. I ahve one PK2 GP9 and seven PK2 GP30. They all run fine. There was a problem with some cracked wheel sets but Walthers replaced them and they run fine after the replacemets were installed.
If you need such a small radius, maybe you should consider an NW2 or SW7/9/12. If you are operating GP locomotives on a shelf layout, they can operate in both directions without turning, so I don’t understand your need for a loop, unless you want some type of continuous running.
The reason I asked about a frame, is because I’m getting a shell from someone, figure I’d save money asking if anyone had one rather than asking walthers.
The reason for the minimun radius is I’m trying to design a shelf layou, but want to be able to just run trains every now and then. (I can go out 3.5’ from the wall, but my arm’s reach is only 3 feet; I could use a ladder I have maying around to fix that.)
My father wants it free-standing, he doesn’t want any holes in the wall when it’s gone, so the question is what to do about turning the train around without stopping.
Maybe I should make a thread on that, since I’m stumped on the new layou design.
Since you are doing a shelf layout, have you thought about around the walls? Maybe a “U” shape and then a movable section that you could put in to complete the circle for just running trains. Before I moved to my present home I lived in several apartments and rental homes. I had the same problem, could not attach anything to the walls. I use modular “dominos” as suggested by David Barrows. My dominoes are 18" to 24" wide and 48" to 72" long. They are made from 1" x 4" framing with 1/2" plywood tops. The dominoes sit on 48" legs. They run the perimiter of the room and stand high enough that you can have usable furniture under them. The entire layout is free standing. I bolt the domino sections together with 1/4" carriage bolts and wing nuts. The layout was constructed with small sections that could be replaced, shrunk or expanded whithout major construction changes to the layout. The majority of these dominoes have survived and are in service in my new basement layout.
I am using sharp european radius, my min. is approx. 16,6". P2K SD9 does negotiate it, but barely. Anything less, I am not sure. But, my max. length of car are 50’ boxcars, so I did not have problems with uncouplings or derailments.
Out of curiosity I bent up a 15" radius curve for you just to see what the loco’s and rolling stock will do. A Proto GP7, GP9 and a GP30 will go around it with no problems. While coupled to a couple 50’ box cars there was still no issues but the cars didn’t look right. With a 60’ box car there were binding issues that will lead to derailing issues for sure. I would suggest you stay away from a 15" curve if by the sounds of it you want to make a complete loop.
I’m currently building the first stage of a new layout, this first part is an L-shaped shelf layout approximately 10’ by 12’. I’m using 12" wide shelfs, and in the corner I was able to fit in a 31" radius curve using Kato HO track. It just barely fits, but it does fit. So even if you don’t want to use that broad a radius, you could easily use say 26"-28" radius curves. Then you could run passenger cars or whatever you wanted. BTW I’m using no.6 turnouts too, they work great on a long narrow space like a shelf.
If you’re talking about like a reverse loop for a loop-to-loop run, I’d try to at least get 18" radius curves. If you can widen out to 4’ you can use 22" curves which will run most anything except passenger cars or long freight cars with body mounted couplers. If your shelfs are say 24" wide, maybe you could make a couple of free-standing 2’ by 6’ sections that you could but up against the shelf to allow continuous running when you want, but otherwise just do switching.