Armor removal and armor screws

[Peter Walsh]

I understand the issues now with the nuts being captive or inaccessible you only have the head of the screw to work on.
The most effective tool I encountered for undoing screws on aircraft (sometimes by the hundred) was a rivet gun with tip adaptor and handle. The principle was that the shock load was applied completely independent of any radial force unlike an impact driver. Of course the screws in that case were 3/16" or 1/4" diameter.
To translate the principle to what you are attempting would require a jack-hammer or pavement breaker fitted with an appropriate tip and a handle to apply rotational force to it.
Maybe just fantasy but who knows what people have laying about the place.

David

In the workshop where I work we use a snap-on el brutus screw removal tool which is similar to this tool:

http://www.aetools.co.uk/product-ape...ractor-300.php

It is a smaller version a locally made tool referred to as a "gutbuster" that we used in the RAAF on the F111 aircraft for removing stubborn panel screws. It works on leverage to hold the screwdriver tip down while you turn it with a rachet or speedbrace. It has an anchor point at one end and a handle at the other end. In the middle is a 3/8" male/female square drive for the tip holder and rachet that can slide along the lever to reach the screwhead you are trying to undo. The closer the tip is to the anchor point, the more leverage you have. The lever and handle were up to 3 feet long. We broke a lot of tips and some even ended up with a nice twist like decorative wrought iron.

You have to remove a screw or bolt (not necessarily the same size/type as you are trying to remove) close to the screw you want to remove and use that screw or bolt to secure the anchor point of the gutbuster to the assembly you are working on. The anchor point had a round metal plate with holes of different sizes to take screws/bolts of various sizes. The gutbuster was a two person job where el brutus can be used by one person easily. In the workshop, we used to chew out up to half of the screws trying to remove them before we started using el brutus. If any, we only chew out the first screw for the first anchor point now. Absolute magic.

As a last resort you could probably make a version of the gutbuster and use heat and penetrant.