Helicoil use
Helicoil use
(OP)
I am designing a console to be use in an airplane. The frame of the console is being built using 6061 T6 1"x1" square tube with a .125 thick wall. I have to attach closeout panels and was going to use helicoil inserts. Is there another insert that is common to use or should I stick with the helicoil?





RE: Helicoil use
Regards,
Mike
RE: Helicoil use
Regards,
Rusty
RE: Helicoil use
http://www.southco.com/landingpages/dzus/
Ted
RE: Helicoil use
It might be a little tricky in tubing, but PEM nuts are very good.
RE: Helicoil use
Helicoils tend to come out with the screw in my experience.
RE: Helicoil use
Steve R.
RE: Helicoil use
That has never happened to me.
Way back a long time ago, I tapped a 1/4-20UNC hole in a piece of scrap aluminium, then I tapped it again and installed a 10-32UNF helicoil insert. I do not know if I achieved full strength, but I could apply lots of torque to my screw.
Are you using the self locking helicoils? I did this on a project, again quite a few years ago, and everyone hated me for it. I have learned my lesson.
RE: Helicoil use
I don't mean that they pull out, but rather come out with the screw when it is removed...
RE: Helicoil use
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Helicoil use
RE: Helicoil use
Most of my stuff winds up on aircraft, and I do not use self locking stuff. I specify screw torques. I specify lubricating threadlocker whenever I can. I am as confident about my clamping forces as I can be by specifying screw torques.
I have looked into specifying tighening angles, but this requires the systematic scrapping of screws, and I have to persuade everyone else to go along with it.
With self locking fasteners, I have no idea what my final clamping forces are, even if my thread inserts do not fail.
RE: Helicoil use
I assumed that elsewhere on the airframe vibration was also a concern, though I suppose that the consequences of failure might not be so terrifically bad if, say, the access panel on a console shakes loose (unless you're in fighter jet world).
RE: Helicoil use
As to pinging mechanics, we had a lot of ex ordanance guys working there and I don't recall them moaning about helicoils that much.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Helicoil use
As to the OP, helical wire thread inserts would be one method, as would key-locked inserts. Rivnuts are definitely a good solution for this particular joint type.
RE: Helicoil use
It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.
RE: Helicoil use
I think I will go with rivnuts.
RE: Helicoil use
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Helicoil use
RE: Helicoil use
Even so, it sounds like the best solution. Can you trim the excess 1/8 plate behind the panel where it is not needed for strength near the screws?
RE: Helicoil use
The device creates a boss the can be form threaded.
They sell the thread forming tools too.
RE: Helicoil use
RE: Helicoil use
More time in the hanger = More expensive repair.
RE: Helicoil use
And since you don't know the configuration any more than I do Its really hard to comment on the idea. I'm more trying to push past the problem and make sure the question is the right one.
RE: Helicoil use
you Could use an anchor nut strip. it might be a real Fuss to get single a/nuts into a 1" sq tube, but i'm sure you could ... you might start by telling the mechanics that they can't do it !
A suggestion ... now (having designed the structure as tube) isn't the time to ask "how are we going to do ...?". it's a design detail that should've been understood at the time of the tube decision. yes, tube looks nice, but a channel would have given you access.