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NickG:
Peter, I've always liked the look of those GLR engines. Will be nice to watch this come together, a proper working steam plant. :thumbup:

klank:
Thank you Nick.

Work in the shop today was somewhat interrupted - s.w.m.b.o. insisted I watched "The Wedding". To be fair, what a joyous day for so many people. Worth watching and wish the couple well.

TIP
Going slightly off topic here, I use the 4 way tool post as supplied with the lathe for the cheapo brazed tip tools - they fit perfectly to exact height.
For most other work, I use a poor man's quick change toolpost (one day I will get a "proper" one - but this does o.k.).
Due to its design (the tool holder hangs over one side away from the tool post itself), the pressure on the tool in the holder, tends to impart a bit of extra "twist" to the tool/ holder, around the post, unless the handle is really done up tight.
I have not seen this tip posted, so will give it here :- for two or three squid, Arc. Euro sell needle roller races, with a pair of thrust washers (top and bottom) to help correct this situation.
I have found fitting one of these sets a real bonus - the cheapo q.c.t.p. now sits exactly where I want it without straining the guts out of the handle. It also works just as well on the 4 way.
A very well worth investment for such a tiny outlay.
I had better add - I have no connection at all with Arc. Euro, except to say they are a very friendly and most helpful firm to deal with.
I have tried to show the race, minus top washer here :-

And in use, here :-

Now, back to the Flywheel.

Rather than just drill'n'ream, I decided to follow Stan Bray's advice and bore the hole first, just in case the drill goes walkabout.
I centre drilled the hub and ran a pilot drill 9/32" dia through.
This is a tad over the dia. of my smallest boring bar (1/4" dia).
With the boring bar tool tip on centre it is then a case of taking small cuts through the bore to bring it to a tiny bit less than the crankshaft dia. (1/2").

Going off topic slightly, there was a most excellent thread recently (I cannot find it right now) on making a "Y axis" read out for a lathe using a long travel dial gauge. (For us lesser citizens who cannot afford DRO set ups - here's wishing!)
Sourceing a long travel plunger dial gauge, without paying through the nose for it was difficult, but once again, Arc Euro came to the rescue. They do one at quite a modest price compaired to flea bay etc.
I now use this set up for really "important" stuff - I find it much more reassuring to see the dial clock hand move with confidence it is right, rather than try to remember the handwheel collar numbers. (I get too confused at the wrong moment using handwheel collars - let alone making sure backlash is dialled out!).
Anyway, for this operation, I set it up for the boring work.

Now its just a question of following through with a 1/2" reamer at slowest possible revs. (The crankshaft is 1/2" dia).

With heart in mouth (cos there aint no going back), I took the flywheel out of the 4 jaw not forgetting to write down all of the appropriate dimensions I have got to. Essential to make the other side a "mirror" of what has been done. Its very difficult to try and measure rim thickness or some such, on the side facing the chuck if you don't - yes I have done that too often.

I then re fitted the flywheel to the 4 jaw with the other untouched side outmost, using a soft faced mallet to get the finished rim hard up against the inside faces of the 4 jaw. A quick look with the lathe running will tell if the machined face is running true - fortunately, mine was.
You don't have to get it dead centred as all to be done now is face the outside of the boss/hub, and bring it to length.

I then turned up a stub mandrel from a length of 20mm mild steel bar. Allow sufficient to hold in your 3 jaw - or I used a collet.
Once this operation is started, the mandrel must NOT be moved form its location - make sure it is held in TIGHT!
All to do with keeping everything concentric at this setting. (Trying to avoid a wobbly flywheel).

Turn down sufficient length, slightly less than the thickness of the flywheel to exactly 1/2" dia. - the thickness of the crankshaft - or better still, keep offering up the flywheel as the turning down proceeds. You need a very good, slop free fit. Leave a good accurate shoulder inboard.
I turned down the end, allowing for the thickness of the flywheel, plus a bit, to 10mm dia, and I threaded this M10 using a tail stock die holder.
The flywheel can now be gripped with a washer and pair of nuts on the mandrel, leaving all of the untouched face plus the rim to be machined without further re-setting.
Here's the stub mandrel.

Just an observation, machining cast iron without suds/coolant makes the casting extremely HOT!!
I suppose coolant/suds could be used, but the clearing up afterwards is disgustingly messy - thick black gooey sloppy muck everywhere. (Done it once - not again unless I have to).

I am very conscious that all of this is very basic to many, but as I said earlier, I am trying to write this for a beginner.
If anything is wrong or dangerous - please shout, 'cos I am learning too - but be kind!

Best wishes,

Peter

saw:
Good work :thumbup: :thumbup:

sbwhart:
Well shown Peter :clap: :clap: :clap:

Stew

klank:
Thanks Benni and Stew.
I'll try and keep going tomorrow.

Did anyone notice my first (deliberate - ha ha) mistake?
I could have, maybe should have, cut the slot for the flywheel keyway fixing, after boring/reaming, whilst still set up true in the 4 jaw.
Oh well, I shall attend to that later.

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