Build Your Own GP20; 2017

What's the best way to section the short hood?

You might want to graft on the short hood from the MTH GP20 shell.

Yep, that is what I do.

I would. Except that the Railking hood is a scale foot too wide and at least a foot too short. 

Yikes. And with the odd shape, shaving out of the center isn't that practical. And I think the short hood on the Lionel GP20 is even wider, though it might be the right length.

 

Now I have to re-examine my plans on correcting a pair of MTH ATSF SD24's (ATSF took delivery of them with GP20 cabs and short hoods).

Stupid question.  But why did you not use a Lionel GP20 It is also scale or at least suppose to be.  I plan on doing something similar. Matting a MTH SD24 with a Lionel GP20. The intent is to create a low nose ATSF SD24.

Not a stupid question.

I measured, and I was off a little. The MTH short hood is only 5" too wide. Not bad.

But, it's two feet too short.

To make it the same length, the MTH can is two feet too long compared to the legacy cab.

Yes. The Lionel short hood is closer, but my original plan was to detail the MTH unit, right up until I put it next to the Lionel. So, now it's cut down the high short hood...

       
       


Picture...

I see two options and remember that all depends of the placement of the forward Can motor if your going to keep it. 

 

1. Section the GP20 shell Cab forward and graft ( add 2ft at the graft point).

 

2. After sectioning the Cab forward. Section it again where hood meets cab and then add 2 scale Ft using styrene to the short hood and reattach to the Cab.  

 Matt,

 I remember you talking about this a while ago. It might work using the MTH GP 20 Cab and hood forward. Same issue placement versus the can motor. Since I now have a SD24 Shell I can hack up instead of screwing up my ATSF SD24 shell, Once the kids are back at school( next week thank god). I have time to start the project.

This is going to be a good thread and I will be watching.

The plan of attack on this was to take the short-hood motor from the powered unit and place it under the long hood on the non-powered unit, install counterweights under the short hoods to balance them, and wire them together since they run as a pair anyway. The other thought was to re-engineer the chassis to re-position the motors, which has been part of the delay on working the project (between all the other stuff that flies into the queue). A third thought was to convert the powered unit to an SD24B (ATSF bought a couple from UP), but research indicated they immediately converted them into slugs. Going to be interesting.

Matt

 

I am assuming with that said you haven't started yet. Since I have 3 pieces of the puzzle to work with no loss ( MTH SD24 Shell, GP 20 Shell and SD24 frame from dummy unit) to work with. I will actually be able to do a test fit. Any way I don't want to high jack Mario's thread but it sounds like their are similar issues at play.  

Here's some pictures for you to reference...

 

I was so excited to see that the Railking nose had a separately applied grab iron on the nose, and would have made my conversion easy, just adding the three more grab irons.

 

In the picture, the blue and red lines are the same size in the top and bottom; the shells were stacked.

 

oh well...

 

Thanks,

Mario

 

 

No hijack... It is going to play out quite similarly.

Glad to hear that many of us are working on the same things, roughly.

I look forward to seeing the concurrent projects evolve. Only one way to do it and that's dive in!

Thanks,
Mario

What about the MPC GP20 nose? That MTH GP20 resembles no GP20 I've ever seen, MPC misses the boat with that stamped metal frame / handrail combo.

I couldn't tell you. I sold my Lionel GP20 when I went scale.

It looks right. 

The MTH handrails are light years ahead of the Lionel PW style stamped frame/handrail combo.

I have a Lionel GP20 shell I picked up somewhere. As I recall, the hood was too wide. I had really wanted it for the cab and had planned on grafting it to the MTH hood and onto the SD24 long hood. I'll take another look at it.

I pulled the Lionel GP20 out of my parts bin. It looks like I will have to add about 5mm to the length of the long hood end of the SD24( Separate the Cab and High hood) Same thing with the GP20. 5mm between the long hood and the GP20 cab and low nose. Width appears to be a match.  I think this will work.