Need a new engine?/Mechanical porn

[Sketchy_Racer]

Could be.

either way, it has to be a accurate finish.

another thought is that i could quite possibly be a competition motor, where absolute accuracy and lightness(not achieveable by casting) is desired. In which that case, yes it would be a plated bore

[sAsLEX]

We charge out our CNC's at work at $160 p/h

= $19,040 of just machine time, let alone other time.

Very expensive engine block yes!

And yours aren't that flash/5 axis at rough guess?

[pete376403]

Iron liners or chrome bores are not always required for aluminium blocks - eg the Porsche Cayenne uses a high silicon alloy which allows the piston/rings to run directly in alloy bores
http://www.rheinmetall.de/index.php?lang=3&fid=1499
"...the engine blocks for the Cayenne are manufactured from the special alloy Alusil. This material has one decisive advantage over conventional aluminum alloys: it provides the necessary wear-resistance on the cylinder bore surfaces – for monolithic engine blocks like for the Cayenne 4.5 l V8 engine. In other words, additional cylinder liners or coatings are not needed"

[Sketchy_Racer]

And yours aren't that flash/5 axis at rough guess?

Nope, ours are just plain 3 Axis ones...


http://www.okumaaustralia.com.au/pro...B-56VA%20&%20B

there we go.. thats the sucker.

[Sketchy_Racer]

Iron liners or chrome bores are not always required for aluminium blocks - eg the Porsche Cayenne uses a high silicon alloy which allows the piston/rings to run directly in alloy bores
http://www.rheinmetall.de/index.php?lang=3&fid=1499
"...the engine blocks for the Cayenne are manufactured from the special alloy Alusil. This material has one decisive advantage over conventional aluminum alloys: it provides the necessary wear-resistance on the cylinder bore surfaces – for monolithic engine blocks like for the Cayenne 4.5 l V8 engine. In other words, additional cylinder liners or coatings are not needed"

So if 1 piston ring snagges, or anything in one cylinder goes wrong, the whole block is rooted...

the price people pay for performance these days huh

[deanohit]

Cool vid mate. these blocks are often used as a compititon motor as the billet alloy is alot stronger and lighter than cast alloy. Some of the top jet sprinters in nz were using these billet blocks last year. Heard that one complete engine made with a billet block cost upward of $100,000. Lot a money for alot a motor.

[McDuck]

Cool vid mate. these blocks are often used as a compititon motor as the billet alloy is alot stronger and lighter than cast alloy. Some of the top jet sprinters in nz were using these billet blocks last year. Heard that one complete engine made with a billet block cost upward of $100,000. Lot a money for alot a motor.

But it is budgetable for a winning machine?

[MGST]

Cool vid mate. these blocks are often used as a compititon motor as the billet alloy is alot stronger and lighter than cast alloy. Some of the top jet sprinters in nz were using these billet blocks last year. Heard that one complete engine made with a billet block cost upward of $100,000. Lot a money for alot a motor.

Yeah Peter Caughy ( sp) has a 540 inch billet big block. Nice if you've got the money aye?

[Titanium]

There is a hole in the bottom once they start the finer stuff and they tip the piece to remove them at times as well, and they spray all the "big mind blank here" liquid about the place to help remove the swarf.





Prototyping would be the only time, or one offs, that I would see this being done.

The Bugatti Veyron W16 has a CNC machined block, head etc. (as do many supercars)



It is typically used in extreme high performance applications where exact tolerances are a must. Also in mass production where a CNC will deliver EXACTLY the same item time after time, you just do not get that with a casting.

But you do pay big dollars for it!

A sold block of aluminum will give a strong finished product than a cast piece of muck metal.

In New Zealand, there was a motorbike engine machined completely from a single piece of billet aluminum in 1 operation (heads, cases, barrels, pistons) just to show what could be done with a 5 (or more axis) machining center.

In the Holden / FORD performance circle here in OZ the big ticket items are CNC machined heads and intake manifolds.

All castings suffer from porosity and therefor are inherently week.

[Titanium]

Iron liners or chrome bores are not always required for aluminium blocks - eg the Porsche Cayenne uses a high silicon alloy which allows the piston/rings to run directly in alloy bores
http://www.rheinmetall.de/index.php?lang=3&fid=1499
"...the engine blocks for the Cayenne are manufactured from the special alloy Alusil. This material has one decisive advantage over conventional aluminum alloys: it provides the necessary wear-resistance on the cylinder bore surfaces – for monolithic engine blocks like for the Cayenne 4.5 l V8 engine. In other words, additional cylinder liners or coatings are not needed"

Jet skis and some 2 stroke bikes have been using nikasil coated aluminum bores for years. It has less friction resistence and allows a cheaper piston ring to be used. The engines are typically free reving.

The new nissan GTR has plasma lined aluminum bores which require a new coating every 12 months!

[sAsLEX]

The new nissan GTR has plasma lined aluminum bores

T r i c k y !

a plasma is typically an ionized gas

[rwh]

A sold block of aluminum will give a strong finished product than a cast piece of muck metal.
...
All castings suffer from porosity and therefor are inherently week.

So how is the billet produced in the first place? Is it something other than a big casting?

Also, you can presumably cast something better than 'muck metal'?

Richard

[YellowDog]

Incredible.

I always presumed they were 90% moulded and the finishing was not so severe.

[Titanium]

So how is the billet produced in the first place? Is it something other than a big casting?

The answer is both yes and no. It may very well be a LARGE extrusion where a cast blank is reheated, normalised and extruded. Possibly from a large round length 5.8 mtrs long 451 mm in dia in to a square form aka round peg in to a square hole.

Also, you can presumably cast something better than 'muck metal'?

Richard

Yes you can.

[P38]

I'm a Toolmaker by Trade.

Easy to see why I fly a desk now instead of a machining center.