Brake System Design

Discuss park gauge trains and large scale miniature railways having track gauges from 8" to 24" gauge and designed at scales of 2" to the foot or greater - whether modeled for personal use, or purpose built for amusement park operation or private railroading.

Moderators: Glenn Brooks, Harold_V

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Topics may include: antique park gauge train restoration, preservation, and history; building new grand scale equipment from scratch; large scale miniature railway construction, maintenance, and safe operation; fallen flags; track, gauge, and equipment standards; grand scale vendor offerings; and, compiling an on-line motive power roster.
rkcarguy
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Re: Brake System Design

Post by rkcarguy »

I don't think using actual brake lining material is a bad idea. I am using the friction material from McMaster-Carr on my build, they have 4 different kinds with various feet/per min, PSI, and temperature ratings. I don't think you can go wrong with real brake show material if that is what you've got.

https://www.mcmaster.com/friction-material/

I have added brake drums to my axles so I have more braking area and longer pad life, that is also not on a tapered surface.
From what I have seen of others work here, many just make their pads square and let them wear into the taper of the wheels.
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Steggy
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Re: Brake System Design

Post by Steggy »

rkcarguy wrote: Mon Dec 21, 2020 5:51 pmI have added brake drums to my axles so I have more braking area and longer pad life, that is also not on a tapered surface. From what I have seen of others work here, many just make their pads square and let them wear into the taper of the wheels.
And then there are disc brakes... :D
truck_ass_1end01.jpg
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rkcarguy
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Re: Brake System Design

Post by rkcarguy »

BigDumbDinosaur wrote: Mon Dec 21, 2020 8:36 pm
rkcarguy wrote: Mon Dec 21, 2020 5:51 pmI have added brake drums to my axles so I have more braking area and longer pad life, that is also not on a tapered surface. From what I have seen of others work here, many just make their pads square and let them wear into the taper of the wheels.
And then there are disc brakes... :D

truck_ass_1end01.jpg

Yes, my locomotive is also going to be getting disc brakes. I've drooled over yours many times BDD. :D The rolling stock will have drum brakes (well sort of, the pads actually contact the outside of the drum) on each axle, made from 4" XS pipe trued up on the lathe at the same time I turn my wheel sets. Because I'm looking at 2.5-3% grades and 4,000#'s or more total train weight, I felt overkill was needed on the brakes.
Glenn Brooks
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Re: Brake System Design

Post by Glenn Brooks »

BDD, wow, amazing set of trucks. Any chance we can see more info on your brakes! Maybe a couple of closeups. Looks like you made them. Can you fill us in on the components?

Love to (attempt) to do something like you show.

Glenn
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Motive power : 1902 A.S.Campbell 4-4-0 American - 12 5/8" gauge, 1955 Ottaway 4-4-0 American 12" gauge

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Steggy
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Re: Brake System Design

Post by Steggy »

Glenn Brooks wrote: Wed Dec 23, 2020 12:40 amBDD, wow, amazing set of trucks.
Thanks for the compliment, although they aren't finished. They will be going under my F7 to replace the Snippe-built (and later heavily modified by me) trucks it was sitting on all this time.
Any chance we can see more info on your brakes! Maybe a couple of closeups. Looks like you made them. Can you fill us in on the components?

Love to (attempt) to do something like you show.
When the trucks are finished I will do a write-up on them and will provide details on the brakes, which were made from a combination of off-the-shelf parts and custom-made pieces, e.g., the caliper brackets.
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Music isn’t at all difficult.  All you gotta do is play the right notes at the right time!  :D
rkcarguy
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Re: Brake System Design

Post by rkcarguy »

http://www.chaski.org/homemachinist/vie ... &start=600

About halfway down the page is my first wheelsets with brake drums for my freight cars. I went with separate drums because I'm looking at up to 3% grades and up to a 4-ton gross weight on my train, so I wanted some serious brakes.

The shoes are not mounted in the pictures of the trucks, but the way they work is I am using springs between the shoes, and then will run cables between the upper arms (think of bicycle brakes but backwards) of the shoes using a frame mounted air cylinder and lever arm to pull the cables from both trucks and RELEASE the brakes. This gets the air cylinder out of the truck itself, allows a single larger cylinder to be used, and is safer than air-on brakes. I lose air pressure, the brakes are set by the springs and I'm stopped.
The brake shoes are laser cut steel, with a pad surface I'll need to form and weld (see drawing) the 1/8" thick plate to match the concave area of the shoe bracket. Friction material can then be riveted and glued to the shoe.
brakeshoe.jpg
freightbrake.jpg
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