Bridgeport Interact 4 Series 2 to Acorn6 build

[suntravel]

If you do not have a machine level, I would use a dial indicator in the spindle for aligning....

Uwe

[richardb15]

I have a 0.01degree digital machine level, I just didn't take a photo using it. To do the final setup I can use the KP1 probe too, lots of options.

[suntravel]

Not CNC related, but since you are into rebuilding old engines, I just made a flow testing thing for carb jets to reproduce parts for old carbs like Amal ect...

Uwe

[richardb15]

I see your rig, what is the white box, a flow meter, or flow & pressure? Myself and my wife make lots of carbs, jets etc for very early machines where it is not possible to obtain parts so we have to make them. If your setup there is a flow meter the varying fuel level, therefore pressure head, will make readings tricky. Actually the way carb jets were sized way back when was to run a set volume through them in a rig similar to yours and time it. I'm sure you know air temp is critical for consistency as fuel changes density quite a lot with temp. You can keep a consistent head by using a float chamber from a carb, or just time a set volume.

How are you making the jet holes? Only drilling them is not so good usually, oval, non parallel jet holes even by 0.01mm makes poor atomisation. We use very finely tapered jet reamers.

We don't own any motorbikes new enough to use Amal carbs, Amac or earlier for us! Our next project doesn't even have a carb as originally built, it just draws air off the top of the fuel tank and whatever vapour is in there, what could possibly go wrong.

[suntravel]

The white box is just a 60s timer for the magnetic valve, so I measure the flow for 60s 1m level and compare to original jets.

I have carbide drills in 0.05mm steps, if they do not hit the value, I figure out the right size with reamers also and regrind a drill for this size.

CNC drilling with carbide gives me less than 0.5% flow deviation in a series of 50 or more.

The reamers are old tools I used for racing with data recording and a lambda sensor to fine tune carbs, today with injection you can do this with a laptop

Uwe