Jd cylinder boring

[46CHF]

Looking for fixturing ideas for boring and honing j and jd cylinders any pics or ideas greatly appreciated

[Eric]

Here some ideas

https://youtu.be/cDfueUhbGqs

https://youtu.be/72y25629Wsg

[Steve Swan]

Here some ideas

https://youtu.be/cDfueUhbGqs

https://youtu.be/72y25629Wsg

Eric, i'm glad you were able to find those links, particularly the top one, i tried unsuccessfully to find that video as that is a fellow by name of Dale Spooner, i have no personal experience with him, but here is his contact info.

Dale Spooner

MOTION MACHINE INC.
560 Memorial Dr.
Danville, VA 24541

(434)799-2604

[T. Cotten]

There are SO many ways to skin a cat, 46CHF!

Obviously, a lot depends upon what machinery you already have, and other resources handy, but I have two suggestions:

Its a lot easier with a fixture that can be shimmed to accomodate various applications (hard to do with a weld...),

And the base flange fasteners should be torqued to the same ft-lbs as when installed to the cases, because in general, large over-bores distort significantly from fastener stress.

....Cotten
PS: I wish I had the time to search out the second link's honing tutorial, as it is commonly impossible to properly over-stroke the bore with the head in the way. (Lycomings were my only experience, and I had to carve some Sunnen stones!)

[Eric]

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[gharper]

Nice creative setup using the machinery that you have!

[chuckthebeatertruck]

The only thing to add is that your master surface is the flange.

The videos and photos show registering to current bore, which may or may not be square to flange.

minor point, the lathes being used In many internet videos are marginal for this work. It can be done, but it is generally easier to achieve a high surface finish with a much bigger, more rigid machine.

[sswaney]

"The only thing to add is that your master surface is the flange"
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[T. Cotten]

"The only thing to add is that your master surface is the flange"

Yes, SSwaney!

Once again Folks; Beware the flange distorts larger over-bores when torqued.

Models with long spigots distort the most; The ideal fixture would support the spigot and accept the flange fasteners the same as the motor cases.

....Cotten

[gharper]

If you're using a lathe, setup, such as Eric did, take a light cut on the base flange as well, then the bore is square with the base flange. Maybe indicate off the base flange first to see if you'r close....