Kenterra Foot Bolts

Posted By: Jim Young Cp Faaop on October 17, 2016


Over the last few years I Have had several Kenterra foot bolts loosen from
the proximal attachment. It was an easy fix to reloctite and torque, but I
was having this issue frequently enough that I made a decision to
preemptively Change the blue loc-tite to red and that resolved the issue. But the
response from Freedom after reporting this problem was thae following:
An initial evaluation has been conducted. A few points:
* We do not recommend changing the torque to a higher value. The
value has been checked and increasing will likely lead to fatigue failure of
the bolt or female threaded components.
* We have had Qty: 1 primary return from the bolt coming loose in
our quality records.
* The Loctite we are using was selected primarily for its oil
tolerance capabilities which we have a need for with the hydraulic oil present
during the manufacturing process. It also aids with serviceability.
* Changing to a Red with less oil tolerance may be a higher risk
than the Blue with more oil tolerance. A change would also need to be
validated before we could implement it or formally recommend it.
* There is very little rotational force on that specific bolt. Very
interesting that his loosened.
I suspect that most of us are fixing the problem without reporting it. How
many of you out there have had a similar issue, and how many times?

SGT. James O. Young Jr., USAF (ret.), B.Sc., LP, CP, FAAOP
AMPUTEE PROSTHETIC CLINIC
Macon Tifton Albany
888FAKELEG
888fakeleg.com

The message above was posted to OANDP-L, the e-mail discussion list for orthotics and prosthetics.