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doubleboost:
At least you are ok :D :D :D :D
You can always see the mistakes after they happen
I had a small truck flywheel come out of a chuck at work years ago the ring gear climbed up the wall :bugeye: :bugeye:, scares me to death thinking about it now.
Engine is looking great :) :) :)
John

sbwhart:
Hi Pleased you lived to tell the tail its always worth relating such incident as others can also learn from them.

I had a similar things happen with a fly wheel but this time it flew of an engine, I decided to experiment by adding a ball bearing to the rocker engine I built, the fly wheel is only small about 2" Dia and i stuck the bearing on with loctite, well the bearing worked a treat it ran like the clapers, then the fly wheel flew off (is that why they call them fly wheels :scratch:) ) did a couple a laps of the shop and crashed against the door, it could quite easily have taken by eye out.

Your engine is looking a treat I like the aditional drive pully, nice work.

:clap: :clap: :clap:

Stew

klank:
John, Stew - thankyou both for the kind words and encouragement.

Just when you think you are doing well - you can get a bite on the bum! Sobering to realise what potential for injury/damage there is in what we do!

What you said is much appreciated.

Peter

klank:
Finally - I got round to the valve chest components.

Here is the valve chest casting as supplied. :-

I rather liked the slightly "raised" pad on the side where the steam inlet piping will go and decided to keep it and make it a little more prominent.
After some basic machining in the 4 jaw and mill I ended up with this - ready for drilling/counter drilling for the valve rod gland. :-

Here is the set up for drilling the 1/4" (blind) hole (for the gland bush), having marked out and popped the mark for the valve spindle - clocking it with a wobbler - SB recommended using washers to protect the larger faces of the valve chest and allow the jaws to grip over the centre recess.
The hole was finished with a D bit :-

No material appeared to be supplied for the valve spindle gland itself, so I turned one from a length of bronze bar and filed the flange to match the shape of the larger shoulder on the end of the valve chest.
The 1/8" hole for the valve spindle was drilled/reamed in the 4 jaw with the gland fitted and secured to the chest with two studs and washers.
The "packing" in the 1/4" gland hole is a neoprene O ring (supplied).
Sorry about the camera shake! :-

The really time consuming/fiddly bit next - making the cover, marking out for the stud holes, drilling/tapping everything and cutting/finishing the studs.

According to the plan, the valve chest cover is a gun-metal casting, but nowadays, a length of brass flat is supplied.
The original plan shows a shallow (1/16") pocket/recess machined into the inside face of the cover, lining up with the area of the valve chest swept by the slide valve.
I was told by GLR that this pocket is no longer necessary - just "make the lid out of the brass flat!"
If anyone reading this who knows about these things - is the shallow pocket important? I don't know - it was obviously put there originally. Does it make the running of the valve more efficient under steam?
I suppose the flat brass "lid" outer surface lends itself to some "embellishment" - HH, in his later build of Tina, etched his initials into the surface - looks very nice! There is a good article on etching in the current issue of MEW.

The original plan calls for 8 x 7BA studs - which SB thinks a little too basic and unprototypical.
After much measuring and head scratching, I marked out for 14 x 8BA studs - but at this time, only drilled for 13 of them.
I am not certain yet what type of union to drill/tap for in the steam inlet pad, and I don't know how much "meat" I will have to play with for the centre stud hole in the upper side of the valve chest. I don't want to end up drilling into a steam passageway.
I ensured my hole spacings would not intrude into the angled internal steam ports in the cylinder.
The really fiddly bit was finishing to length all of the studs from 8BA allthread. I really should get around to making a screw/stud cutting - to - length - jig - useful for all of the myriad of studs needed in an engine!
Anyway - here is the cylinder with valve chest and cover temporarily mounted, minus one stud hole! :-

The valve and steam chests DO line up properly - there is a shadow on the edge of the left hand side of the steam chest where there is a slight casting flaw on the face/edge of the port face of the cylinder!

Maybe I'll have a go at the valve eccentric and strap tomorrow.

Rob.Wilson:
:drool: Hi Peter :bow: :bow: :bow: :bow: doing a grand job :clap: :clap: :clap:

You sure have made good head way since i last looked in :bugeye:

Rob

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