Set screws or threaded rod

When fastening a steam chest to a locomotive cylinder block would you use hex. hd. set screws or threaded rod and nuts.

Eric Studs and nuts

Roy

Wait until Jason sees this.!

He will consider it nothing short of blasphemy that you should even consider hex screws let alone mention them over studs and nuts. And also the correct profile of nuts.!

Nick

Who Me? At least you were thinking of hex head not slotted or socket

As said the prefered method is to take some rod, thread the ends and then use nuts and washers. There is also a practical reason for doing it this way, when you come to set the valve timing you can leave the valve chest cover off to see whats going on while the chest is still supported by the studs, can't do that with screws.

J

Actually a lot of steam chests/covers on locos are held on with csk head slotted screws. Often there is not enough clearance between the valve chest cover and the running board to get nuts in. Sometimes the steam chest is also secured to the block by a couple of csk screws through the steam chest only and between the normal fixings. That way the chest is still secured when the cover is removed for valve timing etc. A chassis I'm working on at the moment has that feature.

As suggested though, studs and nuts are the best way really. I've had a few locos where someone has been a bit over enthusiastic tightening bolts and stripped the threads in the block

John

would eric's Northumbrian loco have had square nuts originally in fullsize? (circa 1830)

cheers,

julian

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Thus making proper studs.

I know little of Steam practice [either full-size, or miniature] but it seems that normal "good engineering" principles would apply.

MichaelG.

(i stand to be corrected but Stephenson's Rocket of 1829 vintage as preserved has no hex nuts - they are all square nuts)

Julian beat me to it, if your prototype is old enough, square head bolts, and studs with square nuts. someone else can start the argument as to which way up the nut should be.(don't go there),

Ian S C

Please go there! I am making a Bolton & Watt bell crank engine.

JA

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JA ... For reference here is "there"

Enjoy

MichaelG.

MichaelG

Many thanks.

JA

Sorry folks (I can hear the cries of despair already) I'm not going for authenticity at the moment I just want a loco that works so hex nuts it will be and probably stainless. However, one of my future projects will be am Armstrong muzzle loaded gun and that WILL have square nuts.

Are we talking stainless for the studs ? or doesn't it matter?