Get well soon Marcus, Cheers Bill.
E: Engine Camshaft
- Thread starter robin stafford
- Start date
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Deleted member 3831
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Camshaft manufacture today is vastly improved over what was possible in the Stevenage era.
Today's CNC programmed cam grinders can grind profiles to a precision that was never possible with the old Berco and Van Norman type machines, which ground profiles from a larger than life size master. And this kind of accuracy is demanded by manufacturers who are involved in high tech racing, where valve control at elevated engine speeds is vital.
Some will say that beyond a certain degree of accuracy an engine cannot respond, but tests have proved otherwise, and have shown that even greater accuracy in terms of angular resolution is increasingly necessary. This is where the sub division of degrees is vital.
In checking a profile to ensure it absolutely matches the design, it is not sufficient just to note the cam lift per degree of rotation, but the need can be to determine the actual arc of a degree, and often in extreme cases, even further to seconds of arc.
So much for near enough being good enough!
What does this have to do with Vincent cams ?
Good question! The answer is that where new cams are to be ground by any of the leading shops who have the Landis, Schaudt or other CNC machines, the accuracy of the finished profiles will be exactly to the design, although of course this does not imply that the design is good to start with. You may never need to be concerned about the detail accuracy of the profile, but it would be there nevertheless.
To grind a profile by directly copying from an existing lobe is to copy all the errors, often making them worse, in the long run a most unsatisfactory method of working.
Has the VOC ever had a batch of cams professionally ground?
I would be interested to learn which profiles, and who the work was entrusted to if such has ever been done.
Just imagine what Phil Irving could have done had he had at his disposal all the design and manufacturing aids that exist today. Something a little better than a Mk2 I'll wager!
Today's CNC programmed cam grinders can grind profiles to a precision that was never possible with the old Berco and Van Norman type machines, which ground profiles from a larger than life size master. And this kind of accuracy is demanded by manufacturers who are involved in high tech racing, where valve control at elevated engine speeds is vital.
Some will say that beyond a certain degree of accuracy an engine cannot respond, but tests have proved otherwise, and have shown that even greater accuracy in terms of angular resolution is increasingly necessary. This is where the sub division of degrees is vital.
In checking a profile to ensure it absolutely matches the design, it is not sufficient just to note the cam lift per degree of rotation, but the need can be to determine the actual arc of a degree, and often in extreme cases, even further to seconds of arc.
So much for near enough being good enough!
What does this have to do with Vincent cams ?
Good question! The answer is that where new cams are to be ground by any of the leading shops who have the Landis, Schaudt or other CNC machines, the accuracy of the finished profiles will be exactly to the design, although of course this does not imply that the design is good to start with. You may never need to be concerned about the detail accuracy of the profile, but it would be there nevertheless.
To grind a profile by directly copying from an existing lobe is to copy all the errors, often making them worse, in the long run a most unsatisfactory method of working.
Has the VOC ever had a batch of cams professionally ground?
I would be interested to learn which profiles, and who the work was entrusted to if such has ever been done.
Just imagine what Phil Irving could have done had he had at his disposal all the design and manufacturing aids that exist today. Something a little better than a Mk2 I'll wager!
