Twin Cylinder Steam Engine

[Darren]

The grind test def says steel...everything I've tried so far seems to be steel....

Grinds nice though, the lathe and mill might not leave a good finish but grinding does....in fact it's superb...

I'll post a pick later, gonna try the shaper now and see how that gets on with it....


I want a surface grinder !!!! Anyone got one they want out of the way.....well, if you don't ask.....

I can see a pattern here....I seem to like working with hard materials.
Mother always said I was difficult, developed it at a young age aparently

[kvom]

I seem to like working with hard materials.

 

Wait until you have to tap those 20+ holes

[bogstandard]

Anything is possible Kirk, if you have enough cash to throw at it.

I personally would prefer to flog myself with something a bit less hard than cast steel.

Darren, there is a good use for it if you can drill and tap it.

Use it for making tipped tool holders. At least you know it is tough. You've proved that.

John

[Darren]

Quick note, the shaper is doing really well, leaves a nice finish....

All I need to know now is if I can tap it, I have tapped hard stuff before 

Pic's coming later got to go the shaper is running....

[Darren]

Well here it is, bear in mind I'm only playing to see what I can do with it. Therefor a couple of blemishes remain....



Facing you is the shapers finish, not perfect but better than the lathe or miller by miles...

Top surface is a quick wipe with a diamond file, and I do mean quick as it didn't take long...
I still think a surface grinder could be a better solution but this will do me for now. It could prob be polised with the buffer and I imagine it would come out like chrome.

Way off track for this thread as I still can't use it for the engine, but while I had it in my hand I couldn't resist seeing what could be done.

It's bloomin hard though, must be able to use it for something....tipped tool holders, nice idea....I fancy a teeny tiny vice.
Yes I know I can buy one cheap enough, but I'd like to have a go at it all the same....

[Darren]

I've been asked by PM what tools I use with my shaper. I thought an answer here may help a wider audience....

OK, I just like to talk a lot....

In this case for the cast steel I used a tungsten tipped lathe tool. It worked just fine and cut very smoothly as you can see.

For other materials I also generally have used lathe tools. For the hardened shaft I made my quick change tool post dovetails I used a HSS with 8% cobolt ground to the shape that was required.

For softer materials such as steel, brass and allloy, I find ordinary HSS lathe tools quite satisfactory.

Hope this helps....

[kvom]

FWIW, I totaled up the number of tapped holes in my block (your number may vary):

Top caps - 10 (I used a pentagonal arrangement for bling.  Fewer will work)
Bottom glands - 8
Bottom plate - 6
Side mounts - 8

So 32 tapped holes plus 4 untapped plus 2 cylinders - lots of drilling and tapping (did I ever mention I hate tapping?) 

One of these days I'll need to total all of the screws that go into this thing.   

[Darren]

Wow....

Is it that many.....brass it is then.....

Thanks for the wake up call.....

[bogstandard]

Gents,

When I made it, it was either use lots of fixings or more complicated machining and joining techniques.

The screws won.

Lots of little easy bits screwed together to make one complicated bit. The crankshaft being a good example.

The cylinder assembly is in fact no more bolt ridden than any other model steam engine plans out there that use this type of valve gear, except for the top plate. The upright supports are usually machined into the cylinder assembly rather than using a plate to support the cylinders. All done to keep costs and machining down.


Bogs

[Darren]

I had a good look at those sash weights tonight with a vision of using one for the cylinder block.



Alas most of them are cast steel, I think one or two may be cast iron but they are too small.....

I had a go at milling one of the steel ones and it machines fine, but it's the small drilling and trappings that give me concern.
So back to brass then, should be a lot safer. I'll save the sash weights for another project sometime.

I wonder why virtually all the sash weight I find are made of steel....?

[shred]

FWIW, I totaled up the number of tapped holes in my block (your number may vary):


One of these days I'll need to total all of the screws that go into this thing.   

I totted up the screws I used one day.. More than fifty IIRC.