CP-173 American Blowdown(s)

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David_W
Posts: 148
Joined: Sat Jan 04, 2003 1:15 pm
Location: Henderson, NC USA

CP-173 American Blowdown(s)

Post by David_W »

For someone who has a RSC American or is familiar with it… The boiler plans for the CP-173 show the blowdown pads (openings) centered on the front and back of the firebox, not on the sides. Do you use them both or just the front one? How do you pipe this? Do you use a short nipple to a blowdown valve and then an elbow out of the blowdown valve pointing- down? to the side? Do I need a “left” or a “right” blowdown valve(s)? How do you operate it (them)?
Dick? Jesse? Bruce? Thanks for any help!
UnkaJesse
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Joined: Sat Jan 04, 2003 10:29 pm
Location: Tennessee, Obion County, Town of Troy

Re: CP-173 American Blowdown(s)

Post by UnkaJesse »

David, Sorry about the delay, but I just now found your post about the RRSC blowdowns. On the plans I had, there was no provision for a blowdown at all!!! I finally figured out that there just might be enough room between the firebox and front axle so I designed me a sort of rotary blowdown valve that I operate from the outside with an extension lever. No elbows or anything, but it blows straight down when open. One is not near enough blowdowns to suit me, but it was the best I could figure out at the time. There just ain't no place to put a valve. I suppose I will have to trust to that Terlyn 5000 to keep things loosened up.

Unka Jesse
"The same hammer that breaks the glass, forges the steel" Russian proverb
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Dick_Morris
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Joined: Sat Jan 04, 2003 2:09 pm
Location: Anchorage, AK

Re: CP-173 American Blowdown(s)

Post by Dick_Morris »

My boiler is steel and I followed the outline of the copper RRSC boiler and the outline drawing that came with the set of prints.It only has a pad at the front - I don't have the prints in front of me, but I suspect that's what they said to do.

My craftsman horizontal band saw came with a flood lubricant kit which had a small ball valve - it looks like it's 1/16 pipe thread (5/16 MTP) and only 1-1/2" long. I ordered an extra to use on the locomotive. The handle was removed, cut down, and a length of 1/8" welding rod was silver soldered onto it. To use, I slip the end of the handle through the wheel spokes and give it a quarter turn.

It looks like there is a street "L" coming out of the boiler. The valve is vertical. On the outlet of the valve goes into a nipple, Ell, and a short piece of tubing. It's aimed to hit just above the rail head. (On the opposite site of the locomotive from the operator.) <VBG>

Not the best arrangement, but it seens to work OK. It's not too difficult to stop for a minute to blow down, but it's easier if you can do it on a trestle or steaming bay.

Since I've seen a couple of local boilers cut apart, I have a suspicion that I should pay better attention to cleaning out the boiler. Before I put more time on it, I need to make an adapter for the pressure washer and see what I can break loose.
Kevin_S
Posts: 454
Joined: Sun Jan 05, 2003 1:22 pm
Location: Sacramento, CA

Re: CP-173 American Blowdown(s)

Post by Kevin_S »

David, on my cp173 I found a blow down valve that just barley fit between the eccentrics, althought like Unka Jesse I can only blow down with an extension lever. I put a baffle plate over mine so the blast is directed downward. I have seen them with a handle ran up to the running board, it operates on the push pull system. on another I have seen them plumbed up to where the crosshead should be on the left side with the blow down mounted on the frame.

-Kevin S.
David_W
Posts: 148
Joined: Sat Jan 04, 2003 1:15 pm
Location: Henderson, NC USA

Thanks guys!

Post by David_W »

Thanks for your replies. Now I know I wasn't nuts or missing something big time, blowdown(s) on this thing are just tough! I don't mind "winging it" when there's no clearcut or obvious answer.
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