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Trying to identify a detail product, but also the name for the detail Locos and rolling stock
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Prolific poster 2,979 posts YoHo Prolific poster 2,979 posts
YoHo

So, I have a bit of a science project on my work bench (and before anyone just tells me to buy the New Athearn Genesis, or a Proto2K on ebay, the goal here is to do the project, that's where the fun lies. Purchasing one is not the answer, I will hand slap anyone who suggests it.

 

Anyway, I have a pair of AHM GP18s on the work bench. I'm planning to do some bare minimum Visual upgrades to them including pilot/steps, Fans and handrailings and potentially grabs. My goal is to keep my detailing costs to around $20 give or take.

My understanding is that on the early versions of the GP18, the 48" fans are similar to the fans on the SD24. While later versions have the flared fans found on the GP20.

Further, my understanding is that those early fans are NOT the same as the 48" dynamic brake fan on the GP7/9. Though I think late model GP9s did use the same fans.

My question is:

What is the name of this fan style? Not pan as that's the GP7/9 fan, not flare as that's the GP20, Flat top is the 2nd gen fan type. So what is this called? and who makes one? Atlas does not have that particular part available for the SD24/26. I've seen an AHM GP18 model with the proper fans, so I know they exist.

I may have to search shapeways, but I'm at a loss as to what to search for.

 
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blindog10 Prolific poster 3,324 posts
blindog10

Yes, "pan top"

GP7s and early GP9s used "cap top" fans.  Late GP9s and SD9s, early GP18s and most SD18s, and all but the last four SD24s used "pan top" fans (flatter than cap tops but still have a bit of a hump).  Late GP18s used early "flat top" fans like those used on GP30s.  Only early GP20s and those last four SD24s were built with "flared" fans.  

Late GP18s and GP20s also had GP30-style sidesills.

So yes, if you can get them, the Atlas SD24 fans are what you're looking for, since the AHM is an early GP18.  Details West makes them but they are not see-thru.  The fans from the Proto:2000 Phase 3 GP9 are correct pan tops.  Or if you get a set of the original P2k GP18 fans you can cut the raised shroud off revealing a pan top fan.  I did this several times.

Scott Chatfield 
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YoHo Prolific poster 2,979 posts
YoHo

Thank you for clarifying the

Thank you for clarifying the different types. This helps a lot.
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blindog10 Prolific poster 3,324 posts
blindog10

Addendum

There is an important difference between the cap top and pan top fans.  The grill of a cap top is made of 36 vanes (slats) standing on edge.  Pan tops and later flat tops have grills made of wire.

And depending on which unit they're applied to, the number of fan blades varies.  GP18s had 6-blade fan hubs over the radiators.  I think the SD24s had 8-blade hubs.  In all cases, the dynamic fans had 12-blade hubs.  (The AHM GP18 doesn't have dynamics.)

Remember,  EMD stands for Every Model Different. 

Scott Chatfield 
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