Recoil inserts in a blind hole
Recoil inserts in a blind hole
(OP)
Hello Everyone,
I have an tapped alluminium part. Should the threads damage we were to use recoil to repair the thread. I have figured out most. I am using 6-32 size insert in some blind holes and thru holes. I am happy with the blind holes but the thru holes are 0.195inches long. But recoil catalogue specifies for a proper fit the hole needs to be 0.279inches. The insert is only 0.138in long (im only using a 1D). I feel it will be ok to install a insert here. If any one else thinks otherwise, please explain.
PS: The metal is already built.
Thanks,
V.
I have an tapped alluminium part. Should the threads damage we were to use recoil to repair the thread. I have figured out most. I am using 6-32 size insert in some blind holes and thru holes. I am happy with the blind holes but the thru holes are 0.195inches long. But recoil catalogue specifies for a proper fit the hole needs to be 0.279inches. The insert is only 0.138in long (im only using a 1D). I feel it will be ok to install a insert here. If any one else thinks otherwise, please explain.
PS: The metal is already built.
Thanks,
V.





RE: Recoil inserts in a blind hole
According to this link a 6-32 x1D only needs a hole length of 0.138.
http://www.recoilinserts.com/Item-Listing-Bulk-Ins...
so I would think your okay
RE: Recoil inserts in a blind hole
RE: Recoil inserts in a blind hole
yes sorry you are correct, I'm looking in this catalogue but can't find where it says 0.195in hole depth.
http://www.alcoa.com/fastening_systems/commercial/...
RE: Recoil inserts in a blind hole
RE: Recoil inserts in a blind hole
Okay I've found it, reading it I think you do need the extra depth to be able to take the tang off the insert but also if you look on page 7 the insert shown is not flush with the top of the tapped hole its two or three threads in, so I think its to do with how the insert is installed.
Why not check with the supplier?
RE: Recoil inserts in a blind hole
RE: Recoil inserts in a blind hole
From a strength point of view it probably doesn't matter because the 0.138" length is the critical part, however if not having that extra length creates problems with the installation, which in turn effects the .138" engaged length then it will matter.
Ask the rep for a written statement that it will be okay and see what the reaction is.
RE: Recoil inserts in a blind hole
Look on page 62 of the catalogue it says:-
Minimum Material Thickness
The recommended minimum material thickness for through-hole applications is equal to the nominal length of the insert plus
one pitch. This allows for proper countersinking and installation of the insert at 3/4 to 1-1/2 pitches below the surface of the
component. In design critical applications, the minimum thickness may be reduced by eliminating the countersink and installing
the insert to 1/4 to 1/2 pitch below the surface
So I think your hole is deep enough.
RE: Recoil inserts in a blind hole
If its the case 1/4 pitch + nom length = 0.040+0.138 = 0.178inch and yes I am safe.
Thanks heaps
RE: Recoil inserts in a blind hole
There are more subtle concerns.
As pointed out by others the insert should always be installed slightly below the surface (and deeper if the fastener needs a counterbore).
The blind hole needs sufficient depth for tapping.