12VCompressor for a Brake Car

This forum is dedicated to the Live Steam Hobbyist Community.

Moderators: Harold_V, WJH, cbrew

User avatar
Greg_Lewis
Posts: 1980
Joined: Wed Jan 15, 2003 2:44 pm
Location: Fresno, CA

Re: 12VCompressor for a Brake Car

Post by Greg_Lewis » Sun Apr 14, 2019 9:46 pm

The Tom Bee unit looks like it is using a plastic tank. If it is, I would not keep the tank. While there have been many online discussions about plastic pipe for air, and many people have successfully used it, some years ago I decided to skip the conjecture and personal opinions and called an engineer at a plastic pipe factory and he said they do not recommend it. He said it can become brittle with age. I personally had a piece of plastic pipe used for air lines shatter after some years of use when I dropped it on the floor. I would not have wanted that pipe to take a hit when under pressure. Considering the comments of the engineer and my experience, I no longer use plastic pipe for compressed air.

BTW, the HF compressor looks quite similar to the Tom Bee compressor.
Greg Lewis, Prop.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 30 years of turning perfectly good metal into bits of useless scrap.

User avatar
cbrew
Posts: 2897
Joined: Sat Jan 04, 2003 12:17 pm
Location: Vancouver Wa

Re: 12VCompressor for a Brake Car

Post by cbrew » Mon Apr 15, 2019 9:14 am

Morning, I am running the Viair 444c for both locomotives.
its the best i have used yet. its not cheap (just under 200 bucks) but when compared to the price of the train set its there to control, its very cheap.
I started using a motor cycle battery, it did ok, moved up to a garden tractor battery, its life span was a little better. I am currently running the largest sealed battery i can find and it will last a day at Train mountain, but it still does not have a lot of head room is the compress is fighting a small leak some where. the steam locomotive currently has three 2"x6" copper tanks, the charge time is about 60 to 90 seconds with this pump. and recovery is about 45 seconds. for the cars, I have switched all the tanks over to alum paint ball tanks i found on amazon. they are larger and it take a while to charge a 7 car passenger tank, but once charged, the recovery is back down to 30 to 45 seconds as i am only needing to charge brake line and the release side of .75" cylinders. as for noise, the viair 444c with the soft rubber feet and the 11 gauge steel tender. its really not bad. I am planning on adding a group 24 RV battery to the tool car and running a 10 gauge power feed up to the tender so i can switch off the small battery when running the long trains. nothing worse then running out of compressor time :)
If it is not live steam. its not worth it.

User avatar
NP317
Posts: 2575
Joined: Tue Jun 24, 2014 2:57 pm
Location: Northern Oregon

Re: 12VCompressor for a Brake Car

Post by NP317 » Mon Apr 15, 2019 9:59 am

Having double-headed with Chris's long train, I can attest to the functionality of his air brake design.
It is capable of quickly stopping his train, and works well when slowing the mass.
Good design and application.
~RN
TM 7-18 #2 small.jpg

B&OBob
Posts: 354
Joined: Sun Jul 22, 2007 8:27 pm
Location: Blue Bell, PA

Re: 12VCompressor for a Brake Car

Post by B&OBob » Mon Apr 15, 2019 11:25 am

Nothing is perfect. The pressure switch and high current relay (especially if "automotive" quality) are subject to failure, possibly allowing the compressor to run indefinitely. While compressor maximum output pressure is self-limiting to some extent, it's worthwhile to incorporate a safety valve in the compressor delivery line "just in csae."
B&OBob

User avatar
cbrew
Posts: 2897
Joined: Sat Jan 04, 2003 12:17 pm
Location: Vancouver Wa

Re: 12VCompressor for a Brake Car

Post by cbrew » Mon Apr 15, 2019 11:33 am

B&OBob wrote:
Mon Apr 15, 2019 11:25 am
Nothing is perfect. The pressure switch and high current relay (especially if "automotive" quality) are subject to failure, possibly allowing the compressor to run indefinitely. While compressor maximum output pressure is self-limiting to some extent, it's worthwhile to incorporate a safety valve in the compressor delivery line "just in csae."
B&OBob
fully concur,
i also use a proper compressor double pole switch with an unloader. switch really cuts down start up current
If it is not live steam. its not worth it.

rkcarguy
Posts: 1504
Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Re: 12VCompressor for a Brake Car

Post by rkcarguy » Mon Apr 15, 2019 12:45 pm

There was a man that was critically injured and did not survive when some plastic air plumbing exploded. Even the polycarbonate bowls on moisture traps and oilers have warnings that they may shatter and should be replaced periodically.
For compressors, I have the larger HF 12 volt compressor, and have used it with the air nozzle for blowing chips out of things during the construction of my locomotive and inflating water toys for my kids. The reviews on both HF models indicate they are a crap shoot, I'd probably buy the Viair if I had to do it again, or when the HF one kicks the bucket.

User avatar
cbrew
Posts: 2897
Joined: Sat Jan 04, 2003 12:17 pm
Location: Vancouver Wa

Re: 12VCompressor for a Brake Car

Post by cbrew » Mon Apr 15, 2019 12:49 pm

rkcarguy wrote:
Mon Apr 15, 2019 12:45 pm
There was a man that was critically injured and did not survive when some plastic air plumbing exploded. Even the polycarbonate bowls on moisture traps and oilers have warnings that they may shatter and should be replaced periodically.
For compressors, I have the larger HF 12 volt compressor, and have used it with the air nozzle for blowing chips out of things during the construction of my locomotive and inflating water toys for my kids. The reviews on both HF models indicate they are a crap shoot, I'd probably buy the Viair if I had to do it again, or when the HF one kicks the bucket.
I believe i had the larger HF pump you speak of, it run good for a couple seasons then it started blowing fuses. that is when i stepped up the viair 444c
If it is not live steam. its not worth it.

rkcarguy
Posts: 1504
Joined: Tue Aug 22, 2017 10:33 am
Location: Wa State

Re: 12VCompressor for a Brake Car

Post by rkcarguy » Mon Apr 15, 2019 4:41 pm

cbrew wrote:
Mon Apr 15, 2019 12:49 pm
rkcarguy wrote:
Mon Apr 15, 2019 12:45 pm
There was a man that was critically injured and did not survive when some plastic air plumbing exploded. Even the polycarbonate bowls on moisture traps and oilers have warnings that they may shatter and should be replaced periodically.
For compressors, I have the larger HF 12 volt compressor, and have used it with the air nozzle for blowing chips out of things during the construction of my locomotive and inflating water toys for my kids. The reviews on both HF models indicate they are a crap shoot, I'd probably buy the Viair if I had to do it again, or when the HF one kicks the bucket.
I believe i had the larger HF pump you speak of, it run good for a couple seasons then it started blowing fuses. that is when i stepped up the viair 444c
Reviews say that the windings on the armature aren't epoxied, the thermal switch fails, and that the unit generally runs hot and kicks out before most people can inflate 4 tires. One user noted that his was rattling and then refused to work(blew fuses) and the magnets had come loose inside the electric motor can. China at it's finest. I'm not sure how well mine is going to work once it's in service.

User avatar
Greg_Lewis
Posts: 1980
Joined: Wed Jan 15, 2003 2:44 pm
Location: Fresno, CA

Re: 12VCompressor for a Brake Car

Post by Greg_Lewis » Mon Apr 15, 2019 4:43 pm

Chris:
Are you running straight or differential air? From your description it sounds like differential.
Last edited by Greg_Lewis on Mon Apr 15, 2019 4:45 pm, edited 1 time in total.
Greg Lewis, Prop.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 30 years of turning perfectly good metal into bits of useless scrap.

User avatar
cbrew
Posts: 2897
Joined: Sat Jan 04, 2003 12:17 pm
Location: Vancouver Wa

Re: 12VCompressor for a Brake Car

Post by cbrew » Mon Apr 15, 2019 4:44 pm

Greg_Lewis wrote:
Mon Apr 15, 2019 4:43 pm
Chris:
Are you running straight or differential air?
auto (differential).
If it is not live steam. its not worth it.

User avatar
John_S
Posts: 709
Joined: Wed Apr 06, 2011 8:21 pm
Location: Cumming, GA

Re: 12VCompressor for a Brake Car

Post by John_S » Tue Apr 16, 2019 7:31 pm

Wayne Davis wrote:
Sun Apr 14, 2019 9:33 pm
Our club uses the Tom Bee compressor unit on our club cars with great results. It powers breaks for four cars.

Wayne

https://tombeeonline.com/collections/to ... essor-unit
I bought his system a few years ago for my boxcar/toolcar/brake air supply car and I went through three of those cheapo compressors before buying a good Viair compressor. I have it mounted on a big block of foam in the boxcar and use a (look out!) 2" PVC tank about 24" long. 40lbs output to the tender prototype brakes plus two cars with Tom's brakes can stop me in a hurry.

User avatar
Pipescs
Posts: 1936
Joined: Wed Feb 03, 2010 10:16 pm
Location: Lester Alabama

Re: 12VCompressor for a Brake Car

Post by Pipescs » Tue Apr 16, 2019 9:22 pm

Thanks for the input to date.

I should mention that this is for the LE American which pulls me a brake car and a caboose with a total weight of 525 pounds with me on it. A long run so far has been two hours and at that point I could barely walk after getting off it.
DSC_5336.jpg
like most LE Americans there is enough steam for the whistle the brakes or the throttle. But only one at a time. Braking to date has been reverse when needed coming down a hill.
IMG_3334.jpg


Looking thru your advice I have decided to order a Viair Pump.

I have a 17 AH Gel Cell to start out with but there is room for something bigger. There is also a 12 Volt charger that is inside the car that I will keep.

In an earlier attempt I machined the valves on old paint ball tanks to take low pressure air lines so I will use a couple of aluminum paint ball tanks for a reservoir to start with.

Is there an adjustable pressure switch that I can use to set the tank pressure around 60 psi?
Charlie Pipes
USMC Retired

Current Projects:

2.5 Baldwin 2-4-2/2-4-4/0-4-4 Conversion (What ever)
Little Engines American Restoration
Bobber Caboose

Post Reply