Undercover cnc porting?

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Undercover cnc porting?

Post by Carnut1 » Sun Dec 09, 2018 1:46 pm

Resized_20181209_130516_1557.jpeg
The question came up to a cnc guy about cheating on a spec cnc head at pri. Cnc guy states no problem, port them and cnc over the porting. Ok, So I tried doing some cnc cover up by hand. Is it possible this would fool anyone? Thanks, Charlie,
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Re: Undercover cnc porting?

Post by Carnut1 » Sun Dec 09, 2018 1:49 pm

Resized_20181209_131509_5377.jpeg
Intake ssr. I was also thinking about using this texture for future designs that might see cnc reproduction. Thoughts?
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Re: Undercover cnc porting?

Post by Carnut1 » Sun Dec 09, 2018 1:49 pm

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Re: Undercover cnc porting?

Post by Carnut1 » Sun Dec 09, 2018 1:50 pm

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Re: Undercover cnc porting?

Post by Dave Koehler » Sun Dec 09, 2018 3:25 pm

Nope, won't fool anyone. If you need the as cast look you will need to blast it with some rocks.
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Re: Undercover cnc porting?

Post by Carnut1 » Sun Dec 09, 2018 3:33 pm

Dave Koehler wrote:
Sun Dec 09, 2018 3:25 pm
Nope, won't fool anyone. If you need the as cast look you will need to blast it with some rocks.
I was shooting for a cnc look! Haha.
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Re: Undercover cnc porting?

Post by Carnut1 » Sun Dec 09, 2018 3:35 pm

I thought I was clear, I did this finish by hand. That was a cast head. Thanks, Charlie
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Re: Undercover cnc porting?

Post by Carnut1 » Sun Dec 09, 2018 3:36 pm

Resized_20181209_125522_2082.jpeg
By hand fake cnc finish.
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Re: Undercover cnc porting?

Post by Morgo » Sun Dec 09, 2018 4:09 pm

Ehh.. there is a class where some CNC-ported head is required? And you try to fool inspectors with hand ported imitation?
If they measure the port dimensions why bother? The port may look very CNC but if the dimensions don't match.. game over.
And by the look;no,those ports don't go as CNC done.
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Re: Undercover cnc porting?

Post by shoedoos » Sun Dec 09, 2018 4:11 pm

If I were the inspector, first thing I would think is "he's run a sand roll over the cnc work.....why would he do that? There must be more to this......"

You wouldn't get a pass from me without some serious explaining....

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Re: Undercover cnc porting?

Post by PRH » Sun Dec 09, 2018 4:36 pm

From what I’ve seen, this usually involves some spec head where certain areas of the ports(port openings and bowls usually) come cnc’d from the manufacturer.

The goal is to modify the port to some degree and then have the cnc’d areas redone to restore the ootb appearance.
Somewhat handy with a die grinder.

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Re: Undercover cnc porting?

Post by RCJ » Sun Dec 09, 2018 4:46 pm

I have gotten worst thru tech, but no I wouldn't let that go as cnc

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Re: Undercover cnc porting?

Post by Carnut1 » Sun Dec 09, 2018 4:58 pm

Morgo wrote:
Sun Dec 09, 2018 4:09 pm
Ehh.. there is a class where some CNC-ported head is required? And you try to fool inspectors with hand ported imitation?
If they measure the port dimensions why bother? The port may look very CNC but if the dimensions don't match.. game over.
And by the look;no,those ports don't go as CNC done.
No, new burr that leaves this finish. I thought it looked like cnc. I am not trying to fool anyone... at the moment.
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Re: Undercover cnc porting?

Post by pcnsd » Sun Dec 09, 2018 5:14 pm

Charlie,
The problem I see is that it does not have the defined tool path direction changes of a machine cut. Machine port work stands out to anyone that has seen it before.
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Re: Undercover cnc porting?

Post by Carnut1 » Sun Dec 09, 2018 5:28 pm

That fake cnc texture was interesting on the flowbench.
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