Piper SENECA II Service Manual page 794

TABLE XIV-VI. MATERIAL AND SUPPLIES FOR COLD REPAIR (cont)
Part No.
The following materials may be obtained from local supply:
Methylethylketone (MEK) can be used instead of Toluol, however MEK
causes very rapid drying and provides only 10 seconds working time
compared with 40 seconds for Toluol.
c. LOOSE SURFACE PLY IN DEAD AREA (NON-INFLATABLE AREA). Peel and trim the loose
surface ply to the point where the adhesion of surface ply to the deicer is good.
1. Scrub (roughen) area in which surface ply is removed with steel wool. Scrubbing motion must
be parallel to cut edge of surface ply to prevent loosening it. Scrub with steel wool and Toluol
directly over all edges, but parallel to edges or surface ply to taper them down to the tan rubber
ply.
2. Cut a piece of surface ply material, Part No. 74-451-23, to cover the damaged area and extend
at least one inch beyond in all directions.
3. Mask off the damaged boot area 1/2 inch larger in length and width than the size of surface ply
patch. Apply one coat of cement, Part No. 74-451-11, to damaged area and one coat to patch.
Allow cement to set until tacky. Roll the surface ply to the deicer with 2 inch rubber roller, Part
No. 74-451-74. Roll edges with stitcher-roller, Part No. 74-451-73. Apply just enough tension
on the surface ply when rolling to prevent wrinkling and be careful to prevent trapping air. If
air blisters appear after surface ply is applied, remove them with a hypodermic needle.
4. Clean excess cement from deicer with solvent.
d. LOOSE SURFACE PLY IN TUBE AREA. Loose surface ply in tube area is usually an indication of
the deicer starting to flex fail. This type of failure is more easily detected in the form of a blister
under the surface ply when deicer is pressurized. If this type of damage (or void) is detected while
still a small blister (about 1/4 or 3/8 inch diameter) and patched immediately, the service life of the
deicer will be appreciably extended. Apply repair patch as outlined in Paragraph a.
e. DAMAGE TO FABRIC BACK PLY OF DEICER DURING REMOVAL. If cement has pulled
loose from the wing skin and adhered to the back surface of the deicer, remove it with steel wool
and MEK. In those spots where the coating has pulled off the fabric, leaving bare fabric exposed,
apply at least two additional coats of cement, Part No. 74-451-24. Allow each coat to dry
thoroughly.
01/01/09
PIPER SENECA II SERVICE MANUAL
Quantity
As required
6 ft. long
As required
As required
3C1
Rolls
1
1
XIV - ACCESSORIES AND UTILITIES
Description
Toluol
Clean, lint-free cloths
(preferably cheese
cloth)
1 in. masking tape
Sharp knife
measuring tape
Fine sharpening stone
Steel wool pads
Hypodermic needles (22
gauge or smaller)