Turning Flywheels & Crankshafts

[putputman]

This procedure takes some time & effort to begin with but it sure makes life easier for any follow on projects. Consider it if you plan to build many models.

I made a plate with a series of tapped holes and fastened it to my faceplate. This plate comes in handy for many operations. I then inserted three 1/4-20 hex head bolts with a jam nut for a spacer. These were positioned so they would support the flywheel in three places. I then faced them off so they run true with the face plate.

I clamped the flywheel in three places over the bolts. Indicate the O.D. of the flywheel and O.D. of the hub and compromise between the two. Now I am able to face off one side of the flywheel and hub, turn the O.D on both the flywheel & hub, chamfer the inside lip of the flywheel, and bore the I.D. all in one set up.

Next I remove the hex bolts and clamp the flywheel directly to the faceplate and indicate the O.D. Then machine the surfaces on that side of the flywheel.

I also use the face plate fixture for turning crankshafts. I made a universal holding fixture that mounts to the face plate.

For each differant crank shaft throw or diameter I make or modify a holding fixture. This allows me to hold the crank shaft securely right next to the offset throw and do the turning.

 

[Brass_Machine]

Very very cool!

So how are the tapped holes on the plate done? What I mean is there a pattern you used?

I think I will be making this one.

Eric

 

[putputman]

Hi Eric,

I really didn't have any plan when I made the hole pattern. I used a hunk of steel that I had on hand. Eight of the larger tapped holes (3/8-16) match the face plate so I could fasten it. The rest were just set on a 15 degree pattern. The radius of the bolt circle kinda just happened. I use 1/4-20 tapped holes as they fit my hold down clamps.

They were put in using a DRO on the mill rather than a rotary table.

You probably can't put in too many holes. You will eventually use them all. I'm sure any way you do it will work out and you will get plenty of use out of it.

 

[T70MkIII]

I think I will be making this one.

Ditto - thanks for the great idea, Arv. I want to do a dual plane V8 crankshaft and haven't decided on whether to do a 1 piece or segmented (as the plans call for). I'm leaning towards the former, but I haven't done a crank before.

 

[Bernd]

Now that is a very neat fixture. That's about all I can say. The picture speaks a 1000 words. :bow:

Bernd

 

[artrans]

wow hats off buddy :bow: :bow: :bow: great idea now I have spend two weeks making one of those.You ever see the movie money pit everything takes two weeks . then a year later still not done :big: And if I try to draw it up first in cad which is kicking my a&& big time I will never do it. BUT I want to ??? ???