Kato F shell on Intermountain F Chassis?

[Tad_T]

First of all, I am not wanting to start a discussion on Kato F’s vs. Intermountain F’s.

The situation is that I have an Intermountain F7A, an F7B and an F3A I got these on clearance when the LHS went under. They are NIB and have only ever been test run on my test track.

These Intermountains are not in road names that I can use. I have extra Kato shells, an F7A, an F3A, and two F7B’s, in a road name that I can use. All of these are already on hand. Since I already have the Kato shells, I am not interested in doing a paint job. I want to mount the Kato shells on the Intermountain chassis.

I have looked for Intermountain shells and they don’t come up often and when they do they are not ones that I am looking for.

I’ve searched and found plenty of information on mounting Intermountain shells on Kato chassis, but not the other way around. I even found magazine articles about machining Kato frames to enable mounting of Intermountain shells

The Kato shell will not fully seat on the Intermountain chassis. It appears that this may be because of the coupler mounts on the Intermountain chassis as has been discussed in the threads on correcting the height on the Intermountain units.

I know that someone has to have done this. I would appreciate any insights from someone who has done this before I start experimenting.

The Intermountains all run well and I like them. I also have an ABBA set of Kato F7’s and an ABBBA set of Kato F3’s. I like them.

I even have an ABBA set of Bachmann Spectrum F’s that are okay, not as good as the Kato or Inermountains, but they are okay. I got the Bmann’s on clearance, too.

If anyone is interested in trading some Kato or Intermountain Santa Fe red & silver war bonnet F’s for a set of NP freight F7A & B and/or a BAR F3, I’d do that. All of these are DC and are the older chassis that take the decoders with shoes.

I don’t mind doing the work to make the shells fit the chassis, but I don’t need reinvent the wheel if someone already knows the best way to go about it.

[mark.hinds]

I have extensive experience in lowering my IM (Intermountain) F-units, but only some of this seems to be applicable to your case.  (Note that although Kato F-units are the correct scale height, the IM ones are too high). 

However, I just test-fit a Kato shell to an IM mechanism.  So if you want a scale-height F-unit, using a Kato shell on an IM mechanism, you would appear to need to do the following:

1)  Remove the front coupler and then the shell from the IM F-unit.  The shell can be removed from the Kato F-unit without removing the coupler. 
2)  Remove the 3 window-glass assemblies inside the Kato shell, so they don't interfere. 
3)  Gradually remove the various spacing fins protruding from the inside top of the Kato shell until the roofline of the shell sits at a scale height of 14 feet above the railhead.  http://www.nprha.org/Diesel%20Diagrams/Forms/Thumbnails.aspx#InplviewHash765015e9-c63e-4284-b03c-fc91800bb2bd=Paged%3DTRUE-p_SortBehavior%3D0-p_FileLeafRef%3DEMD%2520F%252d3%2520Freight%25206000B%252d6005C%2520Mx%252045%252ejpg-p_ID%3D76-PageFirstRow%3D31
4)  Lower the plastic IM fuel tank assembly to the correct height above the rails by cutting off the attachment lugs, putting sheet plastic spacers inside the assembly, and figuring out a way to re-attach it to the shell.  I drilled and tapped a screw on one side of the frame. 
5)  Figure out how to get the now loosely-fitting Kato shell to fit snugly to the IM frame, possibly using trimmed-down window-glass assemblies, and/or sheet plastic. 
6)  Trim down any remaining window-glass assemblies so they can be inserted into the window frames without interfering with the rest of the above. 

MH

[Tad_T]

I have extensive experience in lowering my IM (Intermountain) F-units, but only some of this seems to be applicable to your case.  (Note that although Kato F-units are the correct scale height, the IM ones are too high). 

However, I just test-fit a Kato shell to an IM mechanism.  So if you want a scale-height F-unit, using a Kato shell on an IM mechanism, you would appear to need to do the following:

1)  Remove the front coupler and then the shell from the IM F-unit.  The shell can be removed from the Kato F-unit without removing the coupler. 
2)  Remove the 3 window-glass assemblies inside the Kato shell, so they don't interfere. 
3)  Gradually remove the various spacing fins protruding from the inside top of the Kato shell until the roofline of the shell sits at a scale height of 14 feet above the railhead.  http://www.nprha.org/Diesel%20Diagrams/Forms/Thumbnails.aspx#InplviewHash765015e9-c63e-4284-b03c-fc91800bb2bd=Paged%3DTRUE-p_SortBehavior%3D0-p_FileLeafRef%3DEMD%2520F%252d3%2520Freight%25206000B%252d6005C%2520Mx%252045%252ejpg-p_ID%3D76-PageFirstRow%3D31
4)  Lower the plastic IM fuel tank assembly to the correct height above the rails by cutting off the attachment lugs, putting sheet plastic spacers inside the assembly, and figuring out a way to re-attach it to the shell.  I drilled and tapped a screw on one side of the frame. 
5)  Figure out how to get the now loosely-fitting Kato shell to fit snugly to the IM frame, possibly using trimmed-down window-glass assemblies, and/or sheet plastic. 
6)  Trim down any remaining window-glass assemblies so they can be inserted into the window frames without interfering with the rest of the above. 

MH

Mark,

Thanks for looking into it and your comments.

I had looked at those fins in the top of the Kato shells, but forgot to mention them in my post.  I thought that they might have to be worked on, too. Getting them all even might be difficult. I’ll have to see.

It might just be easier to take them out and then make the proper height spacers from some styrene or something.

Thanks again.

[mark.hinds]

Thinking about it further, maybe it might be better to solve the loose-fitting shell issue first (gradually file down the window insert panels?).  Then gradually remove the fins to lower it.  That way getting all the fins exactly right would matter less, as all you'd need is the front and rear at the correct 14-foot height. 

BTW, in case you haven't seen this elsewhere, I find this jig to be useful for height adjustments.  Construction details should be clear from the image, but make sure the rails extend to the end to make them accessible when using a scale ruler to position the clearance bar: 

[Tad_T]

Thinking about it further, maybe it might be better to solve the loose-fitting shell issue first (gradually file down the window insert panels?).  Then gradually remove the fins to lower it.  That way getting all the fins exactly right would matter less, as all you'd need is the front and rear at the correct 14-foot height. 

BTW, in case you haven't seen this elsewhere, I find this jig to be useful for height adjustments.  Construction details should be clear from the image, but make sure the rails extend to the end to make them accessible when using a scale ruler to position the clearance bar: 

That’s a neat doodad. I had seen that on one of your other posts, but I had forgotten about it.

I have the stuff to rig something like that up.

Thanks.