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How to attach a rod to a grass trimmer crankshaft?

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I sloppily removed the clutch contraption, apparently without functional damage to the grass trimmer.

I need to attach a 1/4 inch aluminum rod to that threaded bolt sticking out from the crankshaft. Looks like it uses an uncommon

5/16"-20 bolt.

Any common or easy to get small plastic or metal parts threaded

5/16"-20?

A workaround (see the picture)...

I suppose some plastic or aluminum could be stuck over the bolt and glued onto the base. And then the trimmer could be started and used like a lathe to cut a hole for the 1/4 inch aluminum rod that it will drive. That assumes the base is sturdy enough to twist the rod. If so, maybe the bolt could be cut off to reduce the depth of the additional material.

Apparently the shiny metal piece stuck on the black plastic is used for timing the engine. With the opposite side of that metal piece being there for a counterbalance. That's my guess.

Thanks.

Reply to
John Doe
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Reply to
rangerssuck

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It's almost certainly an M8 thread. The standard M8 pitch is 1.25mm.

5/16 = 7.94mm 20 TPI = 1.27 mm
Reply to
Ned Simmons

1.25mm.

Right, I'm just looking at the wrong standards, thanks.

Reply to
John Doe

On Wed, 5 Dec 2012 19:24:06 +0000 (UTC), John Doe wrote as underneath my scribble :

So the strimmer RPM measurements I took trouble to make for you in another news group were useful? Not a word of thanks, that behaviour doesnt encourage people to help others, just a thaught in manners.

Reply to
Charlie+

Why doesn't this no-archive nym-shifting author provide the name of the group and the subject, so everyone can inspect my UseNet protocol...

Reply to
John Doe

On Thu, 6 Dec 2012 21:40:40 +0000 (UTC), John Doe wrote as underneath :

What a loon - see your own thread of 5 posts per: From: John Doe Newsgroups: rec.models.rc.air Subject: Can you guess 21.2 CC two-stroke RPM? Date: Mon, 15 Oct 2012

Reply to
Charlie+

In the trial of my UseNet etiquette, I heretofore do by provide the following evidence in support on my own behalf. Referring to the aforementioned fateful thread in which the no-archive nym-shifting troll alleges my violation of UseNet etiquette.

The plaintiff proclaimeth:

I, also known as "the defendant", replyeth thusly: If it's two-stroke, and no trouble, Yes, thanks.

I trust the Court Of UseNet Etiquette to find no fault in the preceding colloquy. I hereby rest my case.

Reply to
John Doe

On Fri, 7 Dec 2012 08:49:33 +0000 (UTC), John Doe wrote yet more drivel

Yawn and a global PLONK - apply filters and - your' gone

Reply to
Charlie+

The nym-shifting no-archive troll doth proclaimeth...

"I'm running off to play with my imaginary kill file friend!"

Reply to
John Doe

Inexpensive 1/2 inch socket

M8 1.25 nut (fits near perfectly into the socket)

5/16" bolt head

Stick the bolt head (bolt part) into a $1000 metal lathe (or a $60 drill press) and tap for the 1/4 inch aluminum rod. Cut off any excess bolt part that still hanging on. Thread it.

Thread the end of the 1/4 inch aluminum rod. Stick it through the socket. Screw the bolt head onto it. Pull it back into the socket opposite the business end.

Screw the M8 nut onto the grass trimmer crankshaft bolt. Stick the socket head over it and glue it. The only radial pressure will be very slight.

Reply to
John Doe

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