Installation and Tooling Selection
Panel Preparation
The following installation procedure pertains to most Delron potted-in type fasteners. Panels are prepared as
illustrated in figures 1 and 2. Drill diameters for various types are shown in the tables below.
Installation Drill Diameters
400 Series
| Size | Type H-HE | S-SE | SF-HF |
| 440 | .375 | .344 | – |
| 632 | .437 | .406 | .500 |
| 832 | .500 | .469 | .562 |
| 1032 | .500 | .469 | .562 |
| 428 | .562 | .531 | .687 |
| 524 | .687 | .656 | .812 |
| 624 | .812 | .781 | .937 |
D1800 (NAS 1800) Series
| Size | D1832, D1833, D1834 | D1835 | D1836 |
| 06 | .561-.566 | – | .452-.457 |
| 08 | .561-.566 | .686-.691 | .452-.457 |
| 3 | .561-.566 | .686-.691 | .452-.457 |
| 4 | .686-.691 | .749-.755 | .499-.504 |
| 5 | .686-.691 | .811-.817 | – |
| 6 | .842-.847 | .874-.880 | – |
Bonding Procedure
Most blind applications for potted-in fasteners can use the “Pre-pot” technique. This involves filling the cavity nearly
full, giving consideration to the displacement factor of an installed fastener. Sufficient potting material must be used
to bond securely yet avoid overflow (Figure 3). Fastener insertion is very simple using the Series 400 SF and 400S-SE
which provide self-retention (Figure 4). Other head styles use tabs to position and hold the fastener in a flush,
perpendicular position. Slots or holes in the tabs and insert head, allow additional potting material to be injected
into the panel cavity (Figures 5 and 6).
Potting Material
Potting materials suitable for sandwich panel inserts are manufactured by companies such as American Cyanamid, Hexcel,
HysolTM , BASF, Ciba-Geigy, etc. Information on type, setting time, and usage may be secure from them.
Installation Sequence
