Sequential fork control drum

[Brian.G]

F1 Ra106 sequential transmission fork control drum,













The notches, allowing insertion with forks installed.









Possibly the most beautiful Motorsport part Ive ever held in my hand.

Measures just 200mm long, and 35mm in diameter. (Approx)

Brian Garvey

[bettonracing]

Thanks for posting the pics (with included reference!).

I'm a little surprised the holes aren't cast into the body, given the part's complexity & the resulting sharp edges of post-processing, but I guess considering they didn't have significant "gearbox problems" drilling must work.

Regards,

H. Kurt Betton

[Brian.G]

Indeed.

Although holes have high surface finish and are de-burred both externally, and internally.

BG

[Formula None]

Beautiful part. Thanks for sharing.

[forty-two]

I know this statement makes me a sad man, but that's exactly the sort of "art" I like looking at. Given the choice between that and a Picasso, I'd choose the part every time!

[Tim.Wright]

Pure porn. how much does it weigh?

Tim

[Brian.G]

Pure porn. how much does it weigh?

Tim

@Forty-two, too true, and agree fully! Mona Lisa my ass!

Tim, my engine part scales is in for calibration, wont have it back for a week, Ill check then. Its not unbelievably light or anything,but it is light.

It also rings like its forged and not cast.

[ringo]

It appears to be forged, judging by the surface.

[johnny99]

Hello Brian, how are you. Where did you get hold of that

John

[Brian.G]

Hello Brian, how are you. Where did you get hold of that

John

John, Ill email you the place. I dont know if posting links to traders is allowed on here, so wont chance it.

[riff_raff]

It appears to be forged, judging by the surface.

Ringo,

It's not forged or cast. It's machined from bar. Likely a chrome-moly steel such as 4340 (or EN40 for those of you in the UK).

First, its OD and ID are rough turned/bored on a lathe. Then the cam grooves, detents, and radial lightening holes are machined on a 4 or 5 axis CNC mill. Then the internal spline is cut with a shaper machine. And finally, the bearing journals are finish ground. It may also have undergone some sort of surface treatment/coating for wear reduction.

Regards,
riff_raff

[tok-tokkie]

To me it looks more like a lost wax casting with a little finish machining. The wax model grown by rapid prototyping machine.

[riff_raff]

Nope. It's machined all over. You can clearly see the lathe turning marks and the surface mismatches from the ball end mill passes.

riff_raff

[Formula None]

Riff, the machining marks on the outside are clear as you point out. What about the ID in the middle being larger than at the ends, are you sure it was also done on a lathe? It seems like quite a reach for the cutting tool, getting inside there.

[PlatinumZealot]

Couldn't it be forged into a preform then machined (similar to a piston) riff raff? it looks forge-ish to me too. I know it's machined but wouldn't you make this from a roll forged bar?

To Brian.G, You have the other parts?