Elbow Engine

[sbwhart]

Elbow Engine

          

OK the project begins, but in truth it started a few weeks ago when John showed me his engine, from that moment  .

Since then I’ve bean exercising my little grey cell    , had a good search through that other site for comments and ideas, and got a set of drawings, had a long discussion with John had a real close look at his engine. Went away did a bit more thinking, made loads of notes, made loads of sketches, got involved with a thread on that other site to try and glean some ideas and comments out of them, collected together bits of material that looked like an Elbow Engine.


Drawing of engine http://john-tom.com/MyPlans/Steam%20Engines/ElbowEngine.pdf

Animation shows how they work. http://80.177.213.1/images/anim.gif

My stash af elbow material



And know I’m ready to cut metal:-

Roughing out flywheel rim.



With a bit of luck, help and encouragement from you guys      I’m going to try and refine the design so that it will be possible for most people to make a running engine and keep their sanity.          

And have a bit of fun along the way. 
 
This will require experimentation, so I’m going to make bits for more than one engine, if one idea doesn’t work I can try something else with the rest of the bits.

The nastiness with this engine comes from:-
 
Mr Square,            Mrs Friction,           and Miss Alignment.

These are the things to try:-

1:- Fit roller bearings in the rotating cylinder.

2:- Fit PTFE O rings on the pistons to act as piston rings.

3:- Refine the piston bending jig, to ensure a dead square bend.

4:- Develop a machining method that will get Mr Square and Miss Alignment behaving themselves.

5:- As a bit of a long shot develop some sort of flexible elbow coupling i.e. spring or rubber.

6:- Try some magic Pixy dust as a lubricant. (Zinc Stearate).

Some of these ideas may sound a bit crazy but one thing I’ve learnt even when an experiment fails you can learn something that can lead to an improvement or a solution.

There’s no such thing as an idea that isn’t worth trying.

So you guys in the collective  please throw in your two pennyworths, good and bad comments will be equally appreciated,

and lets have plenty of humour. 

Cheers
 
Stew



 

[bogstandard]

Stew,

I can knock a few bits off your short list, to save you some  .

1) I had already looked at fitting thin wall ball races, and came to the conclusion it wouldn't be any great benefit. BUT, I did look at fitting a thrust race at either end, based upon bicycle principles, loose balls running in grooved channels, and came to the conclusion that if ever I built a 7 or 9 cylinder one (14 or 18 cylinder count), that would be incorporated. But it would mean machining running clearances of around 0.002" or under, just so the cylinder could rotate and still remain almost airtight.

2) Someone has already tried it, and it caused more problems than benefits.

3) Forget it, you only have to fart near the elbows and they will go out of square. Just bend them to a rough right angle, and fine tweak as you go along.

4) This is good.

5) Forget it, these engines work by pushing the opposing cylinder around, and have to stay in perfect synchronisation, any flex at all will just lock it up solid.

6) Try it, it can only do one of two things, better or worse.

So, I have just got rid of 66.666% of your design ideas, so everything should now go a lot easier for you

I think we are already taking bets on how far you can throw it, any other bets we can take up as well?

I was expecting you to call today, and I had rooted out an elbow for you to play around with, practicing getting it square.

Bogs

[sbwhart]

Hi John

Thanks for your imput  I'd already floated the ideas on that other site, with no fead back at all !!!!!!!.

I thought that some of these ideas would have bean tried before so went fishing for comments.

Bending the elbows:- what I was thinking of was a block of brass to act as a heat sink, machine a slot and a step at right angles with a pin at point of bend:- heat the elbow and band it by eye, clamp it in the block and heat the bend again and let it cool slowly to normalize out the stresses.

The material I've got for the fly wheel is a bit small it will end up about 20mm under size do you think this will be a bad thing. I'm planning for appearance to have a brass/ally composit fly wheel.

I was comming round today after lunch but my boss high jacked me to go round our daughters. I'll see you tomorrow afternoon.

Just for interest for the Guys could you add the U tube video you have of your engine running.

Cheers
 
Stew

[Brass_Machine]

'Magic Bog Water' ??

Eric

[bogstandard]

Complete with stroboscopic effects.

Bogs

[Darren]

'Magic Bog Water' ??

Eric

Yes I was wondering about that?

I have been experimenting with vinegar over the last few days. I'll start a new thread on it with a couple of pic's tomorrow.
Is the magic Bog water anything similar John?

[Stilldrillin]

Elbow Engine

          
So you guys in the collective  please throw in your two pennyworths, good and bad comments will be equally appreciated,

and lets have plenty of humour. 

Cheers
 
Stew

Good luck with the project Stew......   


Humour....... 

Elbow.....

Funny bone......

Humerus..... 




Hmmm..... Sorry...... I`ll get me coat..... 

David.



 

[SPiN Racing]

I was looking at John's clips the other day and came across that elbow engine.. and I have to say.. I sat there with my mouth open all 10 times I watched it. 


It is likely the coolest, crazy bizarre thing I have ever seen. I get it.... but WOW.

I cant wait to see another one undertaken.

I feel like a cave man seeing a I-Phone or something...

[sbwhart]

Fly wheel:-

I like the idea of a composite fly wheel with a brass rim and an ally hub. At the scrap yard I found a chunk of brass that looked about the right size to make two hubs, and whilst there I spotted a pile of scrap pistons, that looked just right for the hub.

Rim

The chunk of brass was trued up with a DTI in the big 6” four jaw chuck and the bore cleaned up, and a small stepped turned in it to locate the hub, the diameter was cleaned up and the rim parted off, it was then trued up again and the parted face cleaned up.





At this point I realised that there was not enough metal to make two rims  OK I’ll have to look for something else for the second rim.

Hub



First job was to run a ruler over the piston to check if there was enough meat to do what I wanted, there was, so it was roughly trued up in the big four jaw, faced up and the diameter turned up oversize to the rim. It was then parted off in: this was done in stages using the tool to open out the grooves to give clearance at the sides to stop the tool getting fouled with swarf because it was such a deep part off.





The pistons machined more like free machining mild steel forming nice chips, a small squirt of bog water improving the surface finish.



That all for now got some domestic duties to attend to next posting in a couple of days.

Cheers
 
Stew

   

[NickG]

Stew,

Congratulations, the hardest bit is always starting the project for me! 

Great post.

Nick

[sbwhart]

 

Found these little beuties whilst on a walk along a disuesed railway track, don't know what I'll do with them but I'm shure they will have a use.



OK back on topic John gave me a pully from a old Myford lathe to make the rim for another fly wheel out off, at first I thought he'd bowled me a googly (swerve ball) the skin was real tough stuff I think it was cast steel but when I got through the skin it machined lovely



To part the rim off I used my big beast tip parting tool my machine moaned and groaned a bit, but I'm used to her ways, know when to ignore here and when to take notice:-

I treat the wife the same way. 



The parting tool is too big for my tool post so I improvice with a clamping set it work very well.



Need to turn another hub up from a another piston than I'll be ready to mill the spokes out on the circular table I'm looking forward to that 

Cheers

Stew

[bogstandard]

Stew,

Would I give you something you couldn't machine. Remember, you only live around the corner, and I saw a few steel pipes when I came round to visit. I ain't fast enough to run away any more.

Nice flywheel rim, and a good fix for pseudo toolpost.

I have some flywheels to make in a couple of days.

John

[Darren]

Hey Stew,

Have you seen how much scrap John collects, leaving pipes out in plain view is just plain teasing him 

[Bernd]

Nice tool holder you came up with there Stew.

Something I'll have to remember. 

Bernd

[bogstandard]

Stew,

A bit , but general interest.

Your pic of the rail spikes reminded me of the time we did a model boat display on the cooling pits for the foundry at Crewe railway works.

As I was walking around the shunting yards, I picked up one of those spikes.

Of course it was an open day and we had all the railway anoraks there. When a large gang of them had gathered to watch us display, I started an impromptu auction and got 10 squid for it, for our favourite charity, the R.N.L.I.

I should have looked around for a few more.

John

[sbwhart]

Of course it was an open day and we had all the railway anoraks there. When a large gang of them had gathered to watch us display, I started an impromptu auction and got 10 squid for it, for our favourite charity, the R.N.L.I.

I should have looked around for a few more.

He He. On that basis I picked up 40 squids worth, there was a load more but my pockets were a bit full:- how much do you recon they'd go for if we spun a yarn that they came from the original Rainhill track 

Cheers

Stew

[Xldevil]

a small squirt of bog water improving the surface finish.

Hello.
Now that I´m no native speaker and because I couldn´t find a good translation for "bog water".
What is it ?
Thanks,Ralph

[sbwhart]

Hi Ralph

Its extracted from fish oil otherwise known as WD40.

But keep it quite I'm trying to keep it secret 

Cheers

Stew

[sbwhart]

Fly Wheel Hub

To clean up the back face a 10 mm Dia mandrel was turned up and the disc mounted on it and the face cleaned up with a bit of “Bog Water” (WD 40) whilst on the mandrel both sides of the disc were given a polish with some scotch bright.



Now for the rotary table work: - My small Vertex table can be used with index plates, but I chose not to use the plate.

The wheel was drawn up on CAD and the off sets coordinates and angle marked on the drawing, as I’m making two wheels of slightly different sizes each size fly wheel was drawn up.





As I don’t have a chuck to fit my table, I modified the arbour used to skim up the back to fit in my table. The table has a M2 taper in the centre, the mandrel was trued up in the lathe and the cross slide moved to 1.5 deg and a short step turned on the mandrel to fit the table, and a M5 hole drilled an tapped to take a cap screw through the bottom of the table.  A rough circle of wood was used as a sacrificial plate; the holes in the wood were on free offer when the wood was bought.



A centre was put into the mill and wound hard into the centre in the end of the mandrel and the Table and the X and Y datum’s zeroed.



Working round clockwise the corner holes were drilled 6.5 dia

With an 8mm dia slot drill the straight sides were machined in one cut:- taking care to feed the cutter the correct way.

Followed by the curve sides.





The hub will be shrunk into the rim   

That was fun   

Cheers
 
Stew

[Stilldrillin]

Nicely done Stew! 

Thanks for showing..... 

David.

[Divided he ad]

Juno what..... I'm getting fed up of people making that look so damn easy! 

One of these days I'm going to try it out and find I can do it!!!   




Good job Stew    Looks like your making a b-line for the fun bit..... Elbows!   




 



Ralph.

[bogstandard]

Having seen it first hand this afternoon, the piccies don't do it justice.

Nice one Stew.

Bogs

[Bernd]

Pretty darn nice work there Stew. 

Must have given you a good feeling when done. 

Bernd

[NickG]

Stew,

That looks fantastic.  How are you going to shrink it in?

Cheers,

Nick

[sbwhart]

Thanks Chaps

I really enjoyed doing it apart from those T bolts it was the first time I'd used my new mill and it was a joy to use, very pleased with it.

Cheers

Stew