Overload

Irab · Posted: Sat Feb 20, 2010 10:09 pm Post subject: Overload

I have an Atlas 'snap switch', that my locomotives are stalling on. They are shorting out the system when they stop with one truck or the other on the frog area. Is is possible, I guess it probably is, that the plastic covering on some part of the frog has worn letting the wheel contact the branch + and the through -?? I can gently shove the loco over toward the through and it will start moving. The longer locos do ok.

I'll just cut it out in the next few days and install another one.

dkrickman · Posted: Sat Feb 20, 2010 10:14 pm Post subject: Re: Overload

Isn't the entire frog on a snap switch plastic? IF it's metal, do engines stall out on it when going through either route, or only one? If it's only one route, you can identify which rail is shorted that way - if both, replacement probably becomes the best option.

Irab · Posted: Sat Feb 20, 2010 11:43 pm Post subject: Re: Overload

Yes, the frog is plastic. It looks like it's not as much plastic as some of the others. I even borrowed some fingernail polish to see if that would insulate it, but to no avail. It is about a little too far to see well enough to work on, but the loco wheels sure seem to have a lot of slop in that area, and if I push just a little toward the through route, it will start moving again. Which reminds me, I super glued a .010 piece of plastic in the frog, but I think I put it on the wrong side. I also think replacement is in order......but we'll see.

Barney

fred_m · Posted: Sun Feb 21, 2010 1:43 pm Post subject: Re: Overload

Don't mean to pester, but old atlas metal frogs were black and looked a lot like plastic. If it has a hole in the frog casting it's metal. If it's plastic look for a loose point on the throw bar that's allowing the back wheel to short across because of the turnout pulling it sideways.

ray_m · Posted: Sun Feb 21, 2010 2:40 pm Post subject: Re: Overload

I have this problem with the Atlas snap switches when I run some locos with wider tread wheels. I haven't figured out a cure yet.
I had thought of filing down the ends of the running rails where they come together at the frog, then filling the area with epoxy and filing it to shape.

Irab · Posted: Sun Feb 21, 2010 5:48 pm Post subject: Re: Overload

All of the locos that I tried were Athearn. All short wheel base locos. The Atlas loco l tried was a longer wheel base and possibly narrower wheel tread, as Ray indicates.
I'll check out the turnout more closely tomorrow and look at the throw bar again. I bought those snap switches in the 80's. That's last century, isn't it???
Raining here today, but hey, the temp is above freezing for a change. Just about 50.
Thanks .
Barney

Irab · Posted: Sun Feb 21, 2010 5:52 pm Post subject: Re: Overload

And by the way, pestering is good.....

thanks,

Barney

gregoblv · Posted: Sun Feb 21, 2010 8:20 pm Post subject: Re: Overload

We have the same problem in 'N'ormal scale with Pico switchs and wide wheels. B'mann older metal wheels have wider tread than normal and bridge the gap between the rails. I was thinking of doing the same thing, Ray.

Irab · Posted: Mon Feb 22, 2010 10:01 pm Post subject: Re: Overload

I cut the 'snap switch' out today and replaced it with another Atlas, mk 4, I think it is. The locos operate smooth as silk at just a scale few mph, Right through with no headlight blink.
I have several other snap switches that don't seem to have the same qualities as the one I removed. Oh well. Now to replace some of the ballast, after I shake it out of the 'dust buster'.....

Wettfeat · Telegraph Operator Joined: Feb 23, 2010 Posts: 12

The same thing happens to my Bachmann Shay on Atlas switches. I know exactly what causes this but I do not know why it only happens to short wheel based locomotives. (I have a Dash-8 and it runs fine over them) What happens is the metal wheel from the locomotive will make contact with BOTH of the closure rails on the switch and will cause a short circuit. If there is some way to alternate which closure rail is powered depending on which way the switch is thrown as to not have both closure rails powered that would fix the problem.

Irab · Posted: Tue Feb 23, 2010 8:46 pm Post subject: Re: Overload

I removed the offending Atlas 'snap switch' yesterday and today I checked it out. It was waaaay out of spec. According to my 'micrometer eyeball', the whole switch was near to and more than 1/16th of an inch too wide,according the the track NMRA gage. At least that is the situation here.

Wettfeat · Telegraph Operator Joined: Feb 23, 2010 Posts: 12

Haha that would also be a problem.