Oversize Insert and Twinsert Kits. Oversize insert kits and Twinsert kits are described In the following
(1) Twinsert kits Packed in sturdy boxes, these kits contain everything needed to salvage abused or
damaged standard thread insert tapped threads in any size shown In table 2-16. Each kit contains a
quantity of 1-1/2 diameter Twinserts and specially shortened mating screw thread or screw lock Inserts
to complete the Twinsert assembly Exception screw lock Twinsert assemblies in sizes 4, 5, 6, and
8 are provided In two diameter lengths only. Each kit also contains a Twinsert bottom style tap and a
Twinsert insert tool.
(2) Oversize kits. Each oversize kit contains a second increment oversize bottom tap and a quantity of
first and second increment oversize screw thread or screw lock inserts, as specified Inserts furnished In
kits are 1-1/2 diameters long.
Spacers. Spacers contained In this section are inserted Into lightweight sandwich-type panels and are used as
fastening points Their use provides a strong lightweight spacer for bolt or rivet fasteners for the Installation of accessories
and equipment where conventional attachments would crush or deform the panel.
Spacer Identification. The spacer shown In figure 2-67 Is a two-piece spacer consisting of a plug and a sleeve
fabricated from aluminum. The commercial method of numbering the types and sizes of sleeves and plugs is
shown In figure 2-68.
Spacer Installation. The selection of the proper type of spacer can be made from figure 2-69, which also
shows the proper drill size required Drill the hole through the entire panel thickness The sleeve Is Installed
through the bottom of the panel, and the plug through the top surface. Final setting of the assembly can be
accomplished by the use of a pneumatic or hydraulic squeezer, or by a hand arbor press For small panels,
final setting can be done with a rawhide mallet with the panel backed up with a heavy block For panels already
installed, a bolt and nut can be used to squeeze the spacer into final setting.
Figure 2-66. Twinsert Installation