Hodgepodge Hiawatha F-7 Build

[Jim Starbuck]

@Jim Starbuck could I ask you to measure the axle centers on each?  The C57 with 72" drivers might not have room for 80" drivers, but the C62 looks like there's some extra room for those flanges.

Here are the measurements to add to the collective information base.

C57:
Driver spacing is .50” give or take a few thousandths.
Driver diameter is .4435  scales to 71”

C62:
Driver spacing is .550” give or take a few thousandths.
Driver diameter is .466”  scales to 74.5”

FEF driver diameter is .4885  scales to 78”

Feel free to check my math on these.
The spacing dimensions are a close ballpark because I haven’t disassembled the engines where I could get a hard measurement on the chassis.

[peteski]

Jim, is the driver diameter taken at the tread, or at the flange?  Flange diameter will be needed for deciding on the driver spacing.

[Jim Starbuck]

Jim, is the driver diameter taken at the tread, or at the flange?  Flange diameter will be needed for deciding on the driver spacing.

Yep. You’re right.
I measured at the tread.
I’ll be right back.

Edit:
I don’t have the drivers out of the C57 or C62 and could not get a good overall diameter measurement of the flanges because of the brake shoes and siderods.
I did get a flange height measurement however.
C57 flange height is .020”
C62 flange height is .023”
Should be able to double those and add to my original numbers.
The FEF drivers measure .530” to the outside of the flange.

If it matters my C62 is an older version with the open frame motor. There was talk earlier of a someone seeing a later release (2018) which may have finer flanges.

[Mark W]

Thanks Jim!  So it sounds like the C62 is what I want to experiment with to get the largest drivers. 
But will that just be a rabbit hole when it comes to rigging up the drive rods?   

Well, only one way to find out!  Time to find a C62 of my own!

[peteski]

Thanks Jim!  So it sounds like the C62 is what I want to experiment with to get the largest drivers. 
But will that just be a rabbit hole when it comes to rigging up the drive rods?   

Well, only one way to find out!  Time to find a C62 of my own!

If you don't change the driver spacing, the original connecting rods should work correctly (regardless of the driver's diameter).

[Mark W]

If you don't change the driver spacing, the original connecting rods should work correctly (regardless of the driver's diameter).

https://i.imgur.com/T5vO9sI.gif

And here I was already thinking if the rods with the FEF drivers didn't line up, I would probably have to fabricate a custom set.  It might have never occurred to me to use the rods from the C62 with the FEF drivers!   

[peteski]

LOL, sometimes one can't see the forest for the trees running gear for the connecting rods, then someone else comes around and creates an AHA! moment.

[ncbqguy]

Sorry if I am repeating this....
The GHQ F7 shell was designed to fit on the Con-Cor NYC J3a or the Kato C62...original version.  I forget the driver diameters but they were undersized even with the increased thickness tires on the Con-Cor China versions.
Kato Non-Bullet Train equipment was traditionally scaled at 1/150 to scale the JNR equipment to better match N Scale track to meter gauge.   
For some reason the C62 with the over engineered cordless motor mech was retooled to 1/160 which made the drivers too small for most North American Hudsons and many Pacifics. 
Micro-Ace C62 might be a better starting point as it has the old Kato-style mechanism but updated and is scaled at 1/150.
Charlie Vlk

[ChristianJDavis1]

Sorry if I am repeating this....
The GHQ F7 shell was designed to fit on the Con-Cor NYC J3a or the Kato C62...original version.  I forget the driver diameters but they were undersized even with the increased thickness tires on the Con-Cor China versions.
Kato Non-Bullet Train equipment was traditionally scaled at 1/150 to scale the JNR equipment to better match N Scale track to meter gauge.   
For some reason the C62 with the over engineered cordless motor mech was retooled to 1/160 which made the drivers too small for most North American Hudsons and many Pacifics. 
Micro-Ace C62 might be a better starting point as it has the old Kato-style mechanism but updated and is scaled at 1/150.
Charlie Vlk

I believe the new Kato C62 is actually 1:150, while the old one was oversized to accommodate the old-style motor. It being oversized may explain why the wheels were closer to 1:160 American stock. I don't see why Kato in this day and age would retool their C62 to be 1:160.

[Mark W]

Package delivery today! 

I've been saving up for C62 since, well May it looks like.  Last week a guy on Facebook was selling one for parts for 40 bucks.   Runs good, just missing the trailing truck and tender, the exact parts I don't need anyway!

So it arrived today, but the thing is noticeably smaller than I expected.  Now, the seller actually sold it as a C57 based on the @spookshow site.  However I was confident it is a C62 based on the boiler features and mechanism.  But now I measure the axle centers at .50" and wheel treads at .449, similar to what @Jim Starbuck measured for his C57.   

So, I've decided I have no clue what I got.  Anyone have any better clues?

I can only say, having just 0.50" axle spacing, I don't think this mechanism is useful for this project, so I'll resume the hunt for the proper mech with 0.55" axle spacing.



https://i.imgur.com/ttgapSk.jpg


https://i.imgur.com/ueeTevr.jpg


https://i.imgur.com/T1HFokE.jpg


https://i.imgur.com/diudwfe.jpg

[ChristianJDavis1]

I believe that is indeed a C62 mechanism based on the pilot wheels, which are solid, as opposed to the C57, which has spoked. The C62's were rebuilt into hudsons from D52 Mikados, so maybe their running gear was built to similar specifications as the C57? I believe the C57's were the last big "purpose-built" passenger engines before the C59's. The C60, C61, and C62 classes were all built from the C59, D51, and D52 classes.

[ChristianJDavis1]

That being said, I wonder if the old, oversized hudson (C62) has a larger wheelbase.

[Sokramiketes]

If you add the trailing truck, line up the shell by putting the steam pipe directly in the middle of the pilot wheels, does it look like the proper cab overhang in the back (based on the GHQ side elevation drawing?)

[Mark W]

Well my Bachmann Hudson finally arrived, and this project is back on track! 


https://i.imgur.com/C1LNGYG.jpg

Rather than carving into the manufactured cylinders to fit the F-7 shell, I plan to just 3D print a new set of cylinders and avoid the risk of breaking anything. 

The NYC shell is metal, and the F-7 shells are now resin instead of metal, so I'll loose a little weight in the conversion.  Even with the metal shell, the tireless Hudson is not that strong of a puller, but the only thing this will ever pull are Fox Valley Models Hiawatha cars; I imagine Bullfrog Snot should take care of it just fine.

[draskouasshat]

Id just bite the bullet and use a cut down gs4 or fef mech. They have the proper box pok wheels and are closer to the 84" the prototype had.