Aluminium cylinder block?

[mzetati]

I'm having ideas about using aluminium instead of cast-iron for the cylinder block of a steam engine: not that I'm much fond of al. for that, but I have not been much lucky into sourcing cast-iron ever (to the point that when I placed an order for a large lump of it in U.K., a few months ago, I got back an e-mail saying 'all items ready for shipping, sorry to tell You cast iron out-of-stock'....)

Back to the point: my idea was about making the body in al. with oversized cylinder bores and then plugging them with bronze rod (if I could find some bronze tubing I could save some money and work).
Press fitting Would be my favorite option. Expected finished cylinder sizes around 1"1/4 dia x 2" stroke.

Would it work ?
What would be the minimum wall thickness on the cylinder liners?
What interference?

TIA
Marcello

 

[b.lindsey]

Will this engine be run on steam or air?

Bill

 

[jct842]

cast iron water pipe turned and bored? I have a henry ford engine under construction using water pipe. john

 

[mzetati]

> Will this engine be run on steam or air?

It will be collecting dust on some shelf.
Still, I want to build it as if it were to be run on steam.

Marcello

 

[firebird]

Hi Marcello

Have a look at the beam engine I have recently completed

http://www.homemodelenginemachinist.com/index.php?topic=10002.0

I used an aluminium brake cylinder for the cylinder with a brass piston.



I have steamed the engine a few times now, it runs ok.

Cheers

Rich

 

[mzetati]

> Rich
> Have a look at the beam engine I have recently completed

WOW!
First question that came to mind, as soon as I saw the first picture, was why did You put all that work into machining such an uncommon flywheel.
Anser came out as obvious when looking at picture three.
Great work!

As for the cylinder block, I already have that lump of unknown (but poor) aluminium alloy, and the bronze: the idea of press fitting them together intrigues me, unless there were big NO-NOs against it.

Marcello

 

[krv3000]

HI well i have made a engine with just a aluminium cylinder block with out a liner fitted run well on air and steam I made the piston out for brass but made 3 piston rings out of Teflon for the xpashon of the aluminium when under steam my engine that im on with at the moment the cylinder is made out of steel see pics regards kvr

 

[Ken I]

Marcello, Just for reference the Porche 928 V8 used a high silicon aluminium alloy for the block - the bores were treated with a "Nicosil" process (a Porche patent) and the pistons / rings ran directly on this - this motor was considered bulletproof.

I would imagine hard anodising would also work well as a cylinder bore.

Using brass and aluminium together in a "wet" environment generates major corrosion problems with the aluminium due to the large potential difference between brass and aluminium.

Ken

 

[mzetati]

> Using brass and aluminium together in a "wet" environment generates major corrosion problems with the aluminium due to the large potential difference between brass and aluminium.

That's not good news, Ken (
So, that will be another air runner, whether I'm lining the cylinders or not.
"next" one will be made into bronze.
Thank You
Marcello