Little and large - building 2 vertical steam engines.

[gary.a.ayres]

Great progress Peter. Interesting process. Not long now till it's running...

[Gas_mantle]

I've now pretty much finished the eccentric strap so that only leaves the eccentric rod to make before being able to carry out a trial run 

Profiling the outer edge of the strap will involve the dreaded turny table so I decided to make a clamping fixture first



With a close fitting spigot and a M6 threaded hole to allow for securing the part I'm hoping this will do the job.



Holes are drilled at 5BA clearance.



A bit of milling reduces the amount of waste to remove later.



Centring on the table with a co-ax indicator



Although only an M6 bolt holds the part down it is prevented from moving by the spigot so it is more secure than it looks and I'm only making small cuts with a 4mm mill.



The lower half is taking shape



Hmmm, it's not perfect - I somehow managed to round the top half at a slightly larger radius but it isn't a complete disaster.





Fortunately it fits over the sheave nicely but I think a bit of running in may be needed. In the following photos it will close up tightly but is difficult to turn so I've got the temporary fixing a bit loose. My hope is that after a while I'll be able to close up the gap fully.





So that largely finishes the eccentric assembly, its never going to win any awards  but on the positive side it does operate smoothly without sloppiness so I'm reasonably satisfied 

[crueby]

Nicely done!




If your rotary table has a hole in the center, you can turn a shoulder on the back of holders like that to match the size of the hole and make it self centering.




 

[b.lindsey]

 Just catching up on this thread Peter. Lovely work and hope to see it running soon.

Bill

[Gas_mantle]

Thanks for the support guys, it's good to know people are still following along 

I'm hoping I'll have it chuffing away in a video tomorrow 

[Gas_mantle]

Only a few photos to but I'm pleased to say I'm now in a position start running the no4 and work towards gaskets, painting, cladding etc.

I had expected to need to add a 'dog leg' in the eccentric rod to achieve alignment with the valve rod but after following earlier advice on making a flat rod with a forked top it became unnecessary (cheers Jason    )

Here I am cutting a small recess and drilling for 7BA clearance  in the eccentric strap.



I added a round bearing ring to the valve rod then set about machining the eccentric rod to fit



The overall shape is largely done here with one side of the fork left to mill down to size.



Although not quite finished in this photo I couldn't resist installing it first to see how things fit together and operate. It needs the top rounding and perhaps a small taper to soften up the appearence a bit but it does operate smoothly.



Well, with all the moving parts in situ it seems a shame not give it a try  ………

<a href="https://www.youtube.com/watch?v=-XAH6_GCdJU" target="_blank">http://www.youtube.com/watch?v=-XAH6_GCdJU</a>

Next job will be to make a boxbed base and an outrigger bearing to support a small pulley.

[Jasonb]

very Nice

[Gas_mantle]

Thanks Jason, I'm quite pleased with it 

I may put the flywheel back in the lathe for a quick spin, at the moment the inner rim casting edge makes it look as though the whole thing has a wobble but the machined surfaces are running true.

[pgp001]

Nice one Peter 

Phil

[Gas_mantle]

Thanks Phil,

I may get it running on the hot stuff today 

[Gas_mantle]

With gaskets and packing added I couldn't resist cooking some water 

<a href="https://www.youtube.com/watch?v=cFsKG-3geHE" target="_blank">http://www.youtube.com/watch?v=cFsKG-3geHE</a>

Since reassembly it appears to have developed a bit of a knock at BDC, I think the piston rod just needs a turn on the screw thread adjustment so it shouldn't be a problem to rectify.

Next job is to make a pulley and outrigger bearing then mount it on the cast iron slab, it will make a great doorstop if nothing else 

[Jasonb]

Not much wrong with that and the little 3" boiler seems to keep up quite well unless you rev it fast.

Have you tried loading up the flywheel with your hand to see what potential it has to drive things, should also give a bit more of a bark when it's under load.

[Gas_mantle]

Thanks Jason, with about 60psi I dont think I could stop the flywheel, it would certainly take some effort if I could, depending what use I put the engine to it will run at perhaps 1000+ rpm so with reduction belt drive it ought to deliver usable torque.

I'd expect the power output to be higher once I have a bigger boiler that is capable of delivering more steam to cope with engine loading.

I have a few old motors laid around so I've just bought a cheapo multimeter with a view to seeing if I can make myself a bit of electricity using the engine.

[Ye-Ole Steam Dude]

Great job and really looks nice under steam.

Have a great day,
Thomas

[zeeprogrammer]

Nice! 

You've got to be feeling pretty good!