3-1/2" Gaugers - Smokebox Access

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Comstock-Friend
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3-1/2" Gaugers - Smokebox Access

Post by Comstock-Friend »

Working on my Coventry B&O D30 0-6-0. In practice, does anybody on run day go in the actual smokebox door or just remove the entire smokebox front? I can't see any real work being done through the smaller door, and not sure I want to mess with 12 door dogs. 32 bolts on the front, are 8 real ones enough to hold it on. Coventry offers no guidance here...

John
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Re: 3-1/2" Gaugers - Smokebox Access

Post by FKreider »

Every 3/4" live steamer I've ever seen has the whole smokebox front come off or hinge open. The actual door and door dogs are typically dummies and/or sometimes the whole smokebox front is a single casting with the details cast right in (this is how Bill Van Brocklin did his smokebox fronts.)

A lot of us hold the smokebox front on with two bolts - one at 3 & 9 o'clock

Edit: I am talking about North American prototypes - most 3/4" British engines do use the actual door and have it hinge open but its much more practical to do so with those engines.
Last edited by FKreider on Thu Feb 18, 2021 8:53 pm, edited 1 time in total.
-Frank K.
KarlKobel
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Re: 3-1/2" Gaugers - Smokebox Access

Post by KarlKobel »

It's the same for 7 1/2 gauge, 1/8 scale. north American prototypes as well.
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Bill Shields
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Re: 3-1/2" Gaugers - Smokebox Access

Post by Bill Shields »

heck..i take the entire front off of my 1-1/2" steamer...and it does have a working door.

my current 1" project has a 'dummy door' bolted to a solid front..that comes off with a thumb latch under the headlight -> you can get it off in 10 seconds if you are blind -> 2 seconds if you know what you are doig..copied from George Thomas. there are 12 dogs there, and the door will open...to a flat chunk of brass behind with no access.

HOWEVER Frank K is correct -> there are a LOT of small steamers in the UK that are built with functional hinged doors and their particular 'wind up' two handled draw bar latch..that are regularly serviced just that way....I have a Tich under the bench. LBSC was a great one for doing this and there are a LOT of locos around based on his design(s).
Last edited by Bill Shields on Thu Feb 18, 2021 5:59 pm, edited 1 time in total.
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LVRR2095
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Re: 3-1/2" Gaugers - Smokebox Access

Post by LVRR2095 »

Coventry’s design used a largish flange on the smoke box front that was just a push fit into the smoke box. There were no screws or bolts and all the ones you see are dummies.
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Re: 3-1/2" Gaugers - Smokebox Access

Post by Bill Shields »

LVRR2095 wrote: Thu Feb 18, 2021 5:59 pm Coventry’s design used a largish flange on the smoke box front that was just a push fit into the smoke box. There were no screws or bolts and all the ones you see are dummies.
he and George Thomas went to different schools together.
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elm53
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Re: 3-1/2" Gaugers - Smokebox Access

Post by elm53 »

I have seen all sorts of securement. Simple is best. As Keith Taylor mentioned a good snug push fit works fine . My 0-4-0 has that set up.my consolidation has two 2/56 screws at 3 and 9 o'clock. An unfinished pacific has scale hinges that allow the whole smoke box front to open . Whichever you decide to use , make sure the entire front comes off and allows as much access as possible to the smokrbox.
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Re: 3-1/2" Gaugers - Smokebox Access

Post by Comstock-Friend »

LVRR2095 wrote: Thu Feb 18, 2021 5:59 pm Coventry’s design used a largish flange on the smoke box front that was just a push fit into the smoke box. There were no screws or bolts and all the ones you see are dummies.
On Coventry's D30, the boiler to smokebox joint and the smokebox to smokebox face joints are 16 each slotted round head 3-48 screws. I have a boiler for it that Henry allegedly made and the front flange does have the 16 tapped holes (these were supposed to have been drilled from the smokebox so not sure the boiler was built solo or from another build).

I'd like to try the slip in style with dummy rivets. Any chance these blow out in operation?

John
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Re: 3-1/2" Gaugers - Smokebox Access

Post by B&OBob »

My 2.5" gauge B&O B-18 Tenwheeler uses a threaded stud on back of the round herald disc in the center of the smokebox cover to hold the cover in place. The "captive screw" engages a removable cross bar spanning the front of the smokebox. This arrangement permits rapid removal and replacement of the cover without small loose parts. A good fit between cover and inside of smokebox ensures a vacuum-tight front end. This method has been used successfully on locomotives from Gauge-1 to 1" scale. And, it is pure LBSC!

My father's 1" 2-4-0 has no screws at all to fasten the smokebox cover: Outside the top-front of the smokebox, there is a flat spring rivetted to the s/b, with a short round stud on the other end of the spring. The stud passes through a hole in the top of smokebox and into a matching hole in the top of the cover. The bottom of the cover has a short stud that drops into a second hole in the bottom rim of the smokebox. To remove the cover, lift flat spring with fingernail, and the cover can be pulled straight back and out.

B&OBob
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