Pantograph clearance

It's going to depend on the locomotive.  A scale proportioned electric will need more clearance than a Lionel PW EP5.  If I remember correctly, even the Lionel PW rectifier needed more clearance than the EP5 with the pan up.

Rusty

I believe you can go the lionels site; the manuels often have sketches.    The scale GG1 has a clearance page for customers---have not looked for others...

They are showing 6.25" from railhead to pan, which is about what we figure we'll be doing on the mountain division of the CL&W.  And a little less where it ducks into tunnels, but not enough to snap the pan down.

Of course, if you guess wrong, the pantographs do easily pop off when they strike the face of the tunnel portal and will not be damaged.  (Voice of experience here.  ALWAYS measure twice.)

Curt

You can always add some light test fishing line to or thin wire to "fix" the maximum height of the pantograph so it can't fully extend.

Fred

Lionel JLC GG-1's require 7" above the railhead.

6.5" or less and you lose a pantograph.

Trust me.

Eliot

I do this with 2 layout. Those things are really high!

Some of the 3rd Rail pantographs are especially high.  Watch out for them.

Not on the JLC GG1's.  They are held on with four tiny screws to the shell.  If you bang them into something, it's not going to end well.

For layouts without wire each loco will not be the same.   When running most electric locomotives under wire, the top of the center rail to the contact wire should be 5 1/8 inches to work properly.

I use a template for a height of 6-1/2 inches from the railhead. I took this measurement as providing sufficient clearance for an MTH Bi-Polar, which is the tallest electric I own. This is for a layout without overhead wire.

Thanks, guys, for the info & suggestions.  I shall try to allow 7.5"....7 if necessary.

Do the pans extend to 7.5" ?

This past weekend I picked up a scale MTH GG-1 with the operating pantographs. To be sure it would make it through the tunnels and bridges on my club layout I first lined it up with the Double Stack car that my club has used as our standard clearance car. the pantographs were about an 8th of an inch lower than the top of the car when up. 

I did an initial test run around the layout, very slowly pushing the double stack. I figured if anything would get in the way let the freight car hit it first. Both the car and locomotive made a successful trip and now i am looking forward to running pantographs up all the time.

Kerrigan made a good point.  That is known as a pantograph skid.  If you have a low tunnel opening, you set the skid so the pan hits it and depresses while inside.  By doing this you should have no problem going into the tunnel.

Using catenary, the same is done by graduating the wire to a lower height.

If you used a quality flex track like Atlas HO you really wouldn't have to take it off the ties. I'd make mounting a lot easier inside the tunnel.

David

From an appearance standpoint, IMO running an electric with the pantographs fully extended with no overhead catenary looks a bit strange.

Ordinarily, the pantograph would meet the catenary well before full extension and limit the height.

Fred's idea of limiting the motion with fishing line or similar is a good one that will improve appearance when there is no catenary. Of course, it also reduces the clearances needed.

Jim