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arnoldb:
Thanks Andrew :beer: - Oh - I take a break every evening to have a Windhoek :ddb: - though it's now getting to that time of the year where the normal Windhoek Lager gets replaced with an Urbock :D - Just gotta love the Namibian Breweries; both summer and winter beers of top quality :)

Today I started off on the valve - but before I started, I fashioned up a Rube Goldberg style air supply from the compressor. There was lots of small milling going to go on, and I didn't buy the new compressor for nothing! A block of bronze (the plans call for brass, but bronze would be just dandy) - and I started milling it to size; no mark-out or anything; this was going to be done by the mill dials only:

The 6mm end mill I used to trim the block down is definitely in need of replacement :lol: - it left a lot of steps on the sides. I used a 2mm end mill to mill the central slot, and the "other side" of the valve; the air flow was set to go over the workpiece, and this pulled the chips right out of the slots while milling:

After milling the cross-slot, I used a slitting saw to slice off the valve from the parent stock:

After a quick de-burr, I flipped the valve over and milled the port face with a 1.5mm slot mill; this is where the air supply really came into it's own. Not much pressure; just 10 psi, but it cleared the chips out of that hole making it a breeze to finish:

After some quick flat-lapping with 800 emery on the glass plate:

And cleaning up on the sides, and ends, the valve was finished:

Then I started on the valve nut - once again no mark-out and just using the mill dials to size it on 3 sides and drill the tapping hole:

Tapped it M2 with my bad-looking handle and tap guide; Elmer specifies the tapping here as "Close", so instead of tapping all the way through with the last tap in the set, I stopped it when I felt it just starting offering less resistance to tapping torque before going all the way through:

Just for exercise, I used the junior hacksaw to saw off the nut:

And then filed it down to size on the sawn-off side.

After a light rub-down on emery, the nut came out to satisfaction:

The valve and nut fits just dandy in the steam chest, with about 0.1mm of free play on the valve to the nut :ddb::

Then I turned up two crank screws from some 5mm hex brass rod:

To my horror, I just noticed some burrs left on them :palm:

Things are finally getting to a point now; I laid out all the bits to check what's still missing:

The to-do list - surprisingly long still!!!
1. Obviously, the flywheel - I hope to get cracking on that tomorrow.
2. There's a couple of parts that still need cleanup to remove burrs and toolmarks. The column actually still needs quite a bit of work now that I look at it.
3. The cylinder block needs to be tapped M2 in 12 mounting holes - Yes, I'll be doing studs 'n nuts again, and I can't do the studs before a final cleanup of the block.
4. Make said nuts from brass/bronze... there's a lot of tapping and filing work in my future :lol: Fortunately I have quite a bit of M2 threaded bronze rod left.
5. A lick of paint - yes, this time some parts will get painted!
6. A final once-over with a buff on some parts and a bit of polymer car polish on those.
7. Wooden base - and all the work associated with that ::)
8. Final assembly - hopefully it will run :coffee:

Regards, Arnold

Rob.Wilson:
Hi Arnold

Looks like you will have a runner soon at the rate your going ,, :clap: :clap: :clap: :clap: :clap: nice going mate :thumbup:

Rob

saw:
It's unfair, it goes to easy for you :(
You wrote that you are going to use car polish, for what?? Will the part got more "bling"?
Nice built Arnold :bugeye:

DaveH:
Looking good, :D

At the speed you are going at will be soon up and running :D

Can't wait :thumbup:

:beer:
DaveH

arnoldb:
Rob, thanks mate :beer: - it needs to get done now; my leave is nearly over and I want to get "cracking" on another project that has some gear - and boiler making involved :D Oh, and I need to build a bridge as well :lol:

Thanks Benni :beer: - I promise you that even though it looks easy it's still a lot of hard work - more than 60 hours on this project, with only about a fifth of it machining, the rest just thinking through things, setting up, checking and double checking measurements and calculations and so on. But it's a LOT of FUN :D.
The car polish I'll use on all the bits I want to keep shiny in the case of polished bits, and to prevent oxidisation (or "patina" as it's sometimes called) on bits with a brushed finish. Just makes maintaining the models easier, as my collection is growing and I like them to look good - even if my first ones were not the best of examples. The polish also helps to prevent rust on the steel and iron bits; I encourage visitors to handle the models, and there's nothing like sweaty fingerprints to make bits rust.

Thanks Dave :beer: - I hope to have it running by the weekend.

Today the flywheel received attention...

I started off with a bit of 55mm cast iron I had lying about; slightly too large and a lot will be wasted, but that's what I had on hand:

My chuck's inside jaws can't open up large enough to safely hold it, so I had to use the outside jaws. With the stock on the short side, I had to figure out a way to get in there to turn it, and also checked for adequate clearances all round so that I wouldn't run anything into the chuck jaws:

Turned down to size; not the greatest finish, as I used the toolbit shown in the previous photo "for the wrong job" :loco: :

The normal toolbit I have for trepanning out flywheels was a bit big for this one, so I had to grind up a new narrower one. Turned out OK, but I had a tiny bit of chatter in the rounded corners:

Then I just center drilled, drilled and reamed the flywheel to fit the crankshaft:

Then I flipped the flywheel in the chuck and cleaned down the other side and trepanned it. I spent some time thinking about milling spokes in the flywheel, but decided against it, and just went for drilled holes. To be a bit "otherwise" I went for seven instead of the traditional six - that meant calculating the odd angles and practising dialling those in on the rotary table:

I couldn't drill the holes all the way through, for fear of running into the chuck jaws, so I drilled them till I could just feel the drill bit want to run through.

Then finished the holes on the drill press with the cross-vise. The drill press is much less rigid than the mill, so the drill bit follows the pre-drilled holes easier and hence much neater:

As a final step, I drilled and tapped a hole at an angle in the hub to take an M3 grub screw. Elmer's plans show the grub screw through the outer rim, but I don't like that too much, hence the digression from the plans. That completed machining on the flywheel:

:beer:, Arnold

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