Wot can it be?

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Good job Tel. I see your moving right along at a good pace.

Today I started back up on mine, after being side tracked with my chuck mounting project and major clean up.

I'm about to start drilling holes in the column. after taking a look at the air passages I got stuck on the 'BB section' drawing in the upper right corner on page 249.

The plugged passage runs all the way through. This doesn't make any sense to me, thinking the engine couldn't possibly run with the upper intake and exhaust ports inter connected.

I was planning on tapping the passages 3-48 for set screw plugs since the 5/64" drilled passages are close to the correct size for tapping. I normally plug with removable set screws. This allows me to go back and make sure the passages are clear, and will also allow me to drill through (BB section) if necessary.

If this isn't a mistake, then is this needed because of the 90 degree offset of the crank throw? ???

-MB
 
Nah MB - that BB section is definitely a mistake, the AA section shows how it should be correctly. In the event, I had no suitable 5/64" drill and went to 2mm, tapped the openings 6BA and put in tight screws that were then cut off and filed flush. I like your idea of removable screws - that could save a lot of problems.

Drilling the passages was pretty straight forward. The only concern I had was with that compound angled lubrication hole. In the end I scribed a light line in the correct position on one face and set that vertical in the vise, then slewed the head of the X2 over 20° - with the vise jaws parallel to the Y axis. Ran in with a 1.2mm drill, then opened out with a 1.4mm - about as big as I dared to go. Seems to have worked out OK - oil squirted in the end comes out the trunnion hole and no where else.

The only other change, so far, is that I thought that space was a bit tight for opening out the trunnion hole for a bush. so I used a bit of K&S 1/4" brass tube to bush the existing hole - means that I'll have to hold the trunnions down to 5.6mm, but that shouldn't make a lot of difference.

It's an interesting build.
 
tel said:
There's probably 15 finished engines here and 1 loco. Time and weather permitting I might try and dig a few out over the weekend and put up a bit of a gallery for ya.

stickpoke

I'd like to see them...especially the loco.
 
Youse blokes are easy pleased - here's an old shot
simplex.jpg


and here's a coal hopper I built for it

lch.jpg
 


Nice loco. Looks like the "Simplex" from Model engineer,1967 or so, I think. Is it?

I have the whole build article on it and have been studying it but the cost of copper tube for the boiler has me just dreaming about it. 4 in well over $100 US.

I've even been thinking of ways to fab up the cast parts from bar stock. Oh well dreams are nice. :big: :big: I'm not good enough to tackle something like this ----YET.

Ron
 
Yes Ron, that's a Simplex - my first loco was a Tich in 3 1/2". Simplex took 5 years of my spare time, between 1985 & 1990
 


I may start on it and make it a long term project like you did. Do what I can when I can.

Ron
 
That's the best way with a loco or other big project - just focus on it bit at a time rather than the whole thing.
 
Nice looking loco and coal car tel. Thanks for posting them.
I'm almost sorry I asked! :big:
I am definitely building a loco...someday.
 
There's a bit of a story goes with that coal wagon. On the originals, the planking is held to the hopper frames with plain round head bolts. Now, being keen to do the right thing I made up a little hand jig and proceeded to make some 300 7BA bolts out of 3/32" rivets - usually doing a few while watching TV - almost an automatic process - until Mrs Tel remarked on the tiny metal shavings that were mysteriously appearing in the lounge room. Any'ow, to cut a long story short, I finished making all of them eventually, and installed them true to prototype, with the heads on the inside of the hopper, then proceeded to fill the dang thing with fine coal, and the heads have never been seen since!
 
Haven't reported on this for a little while, mainly 'cos workshop time has been limited and progress has been in dribs and drab, however, I got a session in on it today and we are beginning to get somewhere.
 
Tel good work! dunno if i missed it, but did you fabricate the crankshaft, or do it nail biting way out of one lump
Regards Max
 
Tel,

I missed this, nice work! Looks like you have a nice powerful osciallator there. What is the pivoty bit on the column that goes around the cylinders?

Cheers,

Nick
 
Thanks blokes.

Max, the crankshaft was fabricated, as per Elmer's instructions (well, almost as per). It was one of the easier crankshafts to do, with that big 'flywheel' section in the middle.

Nick, the 'pivoty' bit is actually fixed in position, it is really only there to carry the tensioning screws that bear on the balls/springs that hold the cylinders up against the port faces. There are a number of ways of doing this, but that is the Gospel according to Elmer, so I went with it.

Looks pretty grubby there, covered in oily fingerprints - it was straight from a running in session on the lathe
 
Oh right that's a novel way of doing it, looks a good way too. Thanks.
 
Well, it runneth - in both directions. Just some tweaking and cosmetic work to go. The sharp eyed will notice that I"ve made a rather radical departure with the reverser - was never really happy with the one in the drawing and, thinking ahead to r/c control when it finds its way into a hull.

 

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