snip
> See the video for more details.
>
> The video is quite impressive. Anyone have thoughts on this before I go
> out tomorrow & buy some inserts?
>
> Mark Rocky Mtn High
>
> Timeserts or heli coils are the only correct way to fix this.
> Heli coils are the easiest to get, but you have to be careful installing
> them. Installed correctly, they are fine for this application. There are
> millions upon millions of aluminum aircraft parts flying around with
heli
> coils in them, as they are used in many new aircraft parts to prevent
> this
> problem to start with.
> The keenserts require a larger tap and will probably not fit due to is a
> limited amount of material in the bolt bosses in the front covers of the
> engine.
> I would stay away from anything other than these inserts types for any
> thread repairs that you want to trust.
> Larry
>
> The URL for Time Serts is www.timesert.com <http://www.timesert.com/>
<http://www.timesert.com <http://www.timesert.com/>> I
> found out about these inserts when working for Kawasaki. Time Serts were
> the only thread repair insert that they approved. A bit harder to get
> than helicoils, but once you have used them once you will never want to
> use a heli-coil again. I don't work for these guys, the reason I'm such
> a strong supporter is the number of threads I have repaired using them.
> I still have several lengths of 6 x 1.0 metric Time Serts in my tool box
> from 20 years ago. Please take the time to look at the web site it
> explains well the difference that make these inserts best. The
> absolutely best thing I can say about these things is that on several of
> the race bikes we built, that we knew would be apart regularly, we Time
> Serted the bolt holes in several of the critical areas to be sure they
> wouldn't fail before we even put the engines together!
> Bill Jepson

Bill, I would agree with you. From what I have seen the 'time-serts'
seem to be the best solution.
It is a solid ferrule, not an individual thread wire. This makes the
most sense.
The outside thread pitch matches the pitch of the repaired thread. The
flange on top prevents the repaired thread from sinking into the bore or
coming out. A little lock tight added would make that one just like a
new thread and very robust.

Thanks for pointing that one out.

Rolf Pfeiffer

Rolf,
A key point ont the Time Sert is that 1-1/2 threads aren't finished.
The last operation is to use a roll tap to stake the sert into the hole.
Believe me I_ LOVE_ locktite but don't use it on Time serts, it isn't
needed and the sert holds the parent metal better without it. The
demo that sold us at Kawasaki was the spark plug repair version.
They brought in a block of 6061AL and tapped it while we watched.
They then took a 4' breaker bar and stripped the hole. They then
handed the kit to the closest guy in the room, and told him to follow
the directions. He did it and the thread looked great. He then handed
the guy a new spark plug and the same 4' breaker bar. The said to try
and strip out the insert. The plug broke off at the body! They took the
block of aluminum out of the vise and turned the plug back out using
the side wire. Then they broke off another plug to show it wasn't a
fluke. Obviously this wouldn't be likely with a solid bolt, but the
tearouts
test to more than double the original shear strength in aluminum.
Bill Jepson



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