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  • Alco RS11 modeling project - dynamic brake details

  • Discussion of products from the American Locomotive Company. A web site with current Alco 251 information can be found here: Fairbanks-Morse/Alco 251.
Discussion of products from the American Locomotive Company. A web site with current Alco 251 information can be found here: Fairbanks-Morse/Alco 251.

Moderator: Alcoman

 #386193  by lupilup
 
Hello to all Alco fans!

As a model railroader from Germany I recently fell in love with the Alco RS11. I'm modeling in 1:29 scale and there is no RS11 on the market. So I decided to scratchbuild one. The powered AAR type B road trucks are offered as replacement parts from Aristocraft (used on their RS3, U25B and Alco FA1). I found many photos on the internet and some scale drawings from side shots but I wasn't able to find blueprints. My special question to you is if someone can show me detail shots from the dynamic brakes. I couldn't recognize if there should be grids over the outlets. I looked on photos of the RSD12, RSD15, C424 and C425 that may have similar ones but couldn't find photos that showed the roof details close enough. Blueprints would also be very appreciated.

Rolf

 #386216  by Paul
 
I am going to work on an Rs-32 on Saturday, 4-14-07. I will be pulling the fans off the dynamic brake grid blower motor. The hatch is on the ground so I can get as many pictures and measurements as you wish. You will need to convert them to metric. I hope this will help.

 #386218  by lupilup
 
Paul, thank you very much :-D ! Converting the measurements to metric is no problem. Detail pics would be very helpfull.

 #386347  by tgibson
 
Hi,

Here is an RS-11 roof shot - there are parallel grates over the DB openings:

Image

Hope this helps,

 #386515  by lupilup
 
Tom, thank you! That is a first help. I already had found this picture but could not figure out what is there exactly over the openings.

Further questions: Are those openings square holes? Are the resistors of the brake cooled only by air? Where is the air inlet?

Rolf
Last edited by lupilup on Sat Apr 14, 2007 7:43 am, edited 1 time in total.

 #386734  by Typewriters
 
Image


Note lower, side view showing internals of dynamic brake resistor and blower assembly. Air taken in at center, and can go thru either blower fan thru the resistor grids; directed by baffles up through square exhaust vents as shown in roof view and in photo previously posted.

-Will Davis

 #386879  by lupilup
 
Will, thank you very much! Those drawings will be a very big help for me building my model. :-D

 #387820  by Paul
 
As promised, and I hope these help:
Image
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Now, anybody know here I can borrow a puller, GE part number 675399G4 & G2 so I can remove the fan and bearings from a 5GY19PA3 blower motor?

 #387825  by lupilup
 
Paul, this helps very much. With the drawings from Will, the description from Tom and your detailed photos there won't be any question left and I won't have problems building the dynamic brake unit for my model.

Thanky you all!

Rolf

 #387831  by Paul
 
By the way, the set back for the exhaust vents are 2.5 inches from the end and 5.75 inches from the sides. They are 15X31.5 inches.The air intake (center) vent openings are 34.5 X 2.75 inches. Total length of the hatch is 134.5 X 48 inches. The hight of the air hatch at the centerline on the roof is 2.5 inches

 #388290  by tgibson
 
Hi,

BTW, the expanded metal over the top openings were added sometime after delivery (to keep people from stepping on the grates).

Also, I think the air intakes on the sides at the middle of the unit were also added later.

Hope this helps,

 #390060  by Typewriters
 
I think we have some different housings shown in the various pictures and drawings.

A close look at the operating manual for RS-11 and RSD-12 locomotives reveals that the dynamic brake housings are different; note on the drawings I've linked that the housing, between the air outlets, has two panels. The RSD-12 housing is longer and has three panels. Neither has any sort of air intake above the roofline at the center. The detail internal view of the dynamic brake housings clearly reveals a larger number of resistor grids inside the (longer) housing on the (six-axle) RSD-12 as compared with the (four-axle) RS-11.

The operating manual for Century series locomotives (in this case C-420) shows what appears to be a dynamic brake housing identical to that pictured removed from the RS-32; namely, three sections with side intakes above the roofline.

I do rather think, then, that the color photos (which are excellent by the way and the first I've ever seen anywhere) showing the complete housing removed do not apply to the RS-11, at least early (publishing date of the manual I scanned the drawing from is Feb. 1956) and probably apply to RS-32 and later (and probably RS-36.)

-Will Davis