From billets to flywheels.

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Braaap
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From billets to flywheels.

Post by Braaap »

Let the fun begin

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Expat
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Re: From billets to flywheels.

Post by Expat »

Cuh, it's like being at work. ;)

So, when will they be finished? 8-)
Keep shiny side up.

These are my principles, if you don’t like them, I have others. (Groucho Marx)
Braaap
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Location: New Zealand

Re: From billets to flywheels.

Post by Braaap »

Cupla weeks should sort them. I need to decide what to machine first... and make a fixture to simplify the copying process.
I'm thinking... face and bore the mainshaft hole. Machine half of the O.D.
Etc...
Fit the mainshaft hole on an offset pin to machine the big end and balance holes...
Braaap
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Re: From billets to flywheels.

Post by Braaap »

Progress tonight....
HEAVILY cropped pic to get the file size under 1 Mb.

One side faced. O.D. half machined. Mainshaft hole drilled.
Tomorrow when it's cold i'l bore the mainshaft hole
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Expat
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Re: From billets to flywheels.

Post by Expat »

How's your chuck run? Will you want to machine soft jaws to maintain concentricity or is that a bridge too far?
Keep shiny side up.

These are my principles, if you don’t like them, I have others. (Groucho Marx)
Braaap
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Location: New Zealand

Re: From billets to flywheels.

Post by Braaap »

The whole job is being done in the 4 jaw chuck.

If u want it close... use a 3 jaw chuck. If u want it bang-on... use a 4 jaw 😊

Once the mainshaft hole is bored (with a recess for the head), i will machine the other wheel to the same stage.
Then hold them by the finished part of the O.D. to machine the other side and finish the O.D.

Then devise a fixture that has a peg offset by 42.75mm (half of 85.5mm stroke)...
Mount the wheels on the peg, (expanding bush?), and machine the big end holes. Balance weights will be needed, so my small lathe bores a round hole.
Any tiny error will be the same on both wheels...

What could go wrong?
Dixter
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Re: From billets to flywheels.

Post by Dixter »

Interesting process. Two questions, what did you decide on the interference for the mainshaft, and big end pin? Do you have access to a milling machine.

Ciao,
Dick
Dick Casey
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Re: From billets to flywheels.

Post by Expat »

Braaap wrote:The whole job is being done in the 4 jaw chuck.

If u want it close... use a 3 jaw chuck. If u want it bang-on... use a 4 jaw 😊

Once the mainshaft hole is bored (with a recess for the head), i will machine the other wheel to the same stage.
Then hold them by the finished part of the O.D. to machine the other side and finish the O.D.

Then devise a fixture that has a peg offset by 42.75mm (half of 85.5mm stroke)...
Mount the wheels on the peg, (expanding bush?), and machine the big end holes. Balance weights will be needed, so my small lathe bores a round hole.
Any tiny error will be the same on both wheels...

What could go wrong?

Sounds good but can't you mount on a mill, clock the hole then pitch over the 42.75?

Maybe I'm missing summat?
Keep shiny side up.

These are my principles, if you don’t like them, I have others. (Groucho Marx)
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Expat
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Re: From billets to flywheels.

Post by Expat »

Dixter wrote:Interesting process. Two questions, what did you decide on the interference for the mainshaft, and big end pin? Do you have access to a milling machine.

Ciao,
Dick

I'm guessing 0.0005 to 0.001.
Keep shiny side up.

These are my principles, if you don’t like them, I have others. (Groucho Marx)
Braaap
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Location: New Zealand

Re: From billets to flywheels.

Post by Braaap »

I had the luxery of measuring some Wolf flywheels... and i have these factory ones. The interference fit on all the mainshaft bores is: One and a half to two thousands of an inch. My first hole is maybe half a thou tighter.

The thing with "moving over from the center" in the mill is: u need an absolutely square machine to do them statically.
Spinning the wheel onto a stationary tool (in a lathe ) allows checking for runout before beginning the hole. Also any clocking error when picking up the center would misalign the mainshafts?
My flywheels may not be EXACTLY 85.5 stroke. But they will be th same

Yes i do have a small mill drill
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