Cement Application; Installation Of Deicer And Required Materials - Piper Navajo Chieftain PA-31-350 Service Manual

NAVAJO CHIEFTAIN SERVICE MANUAL
14-48. CEMENT APPLICATION.
a.
Using a silver pencil, mark a centerline on the glossy side of the deicer.
b.
Moisten a clean cloth with MEK or acetone and clean the unglazed surface of the deicer, changing
cloth frequently to avoid contamination of the clean area.
c. Thoroughly mix the 1300L cement. Apply one even brush coat of cement to the unglazed back
surface of the deicer. Cement one inch of the deicer lead strap. Allow to air dry for a minimum of one hour
at 40°F or above, when the relative humidity is less than 75%. If the humidity is 75% to 90%, allow two
hours drying time. Do not apply cement if the relative humidity is higher than 90%. After allowing the
proper amount of drying time, apply a second even brush coat of 1300L cement.
NOTE
If curling of the deicer edges is a problem, apply masking tape to
the edges of the glazed side before applying cement to the
unglazed side. Remove the tape before starting to install the
deicer.
d. Apply an even brush coat of 1300L cement on the cleaned surface of the propeller blade.
immediately after the second coat of cement has been applied to the deicer. This timing is important for
the cement on both surfaces to reach the tack stage at the same time.
14-49. INSTALLATION OF DEICER AND REQUIRED MATERIALS. It is imperative that the following
instructions be followed exactly to insure maximum adhesion to the propeller blades.
a.
When the cement coats are tacky dry on both propeller surface and deicer surface, proceed as
follows:
I.
Position the deicer on the propeller leading edge, using centerlines starting from the hub. ( Refer
to Figure 14-17.) Make sure that the strap will fall in the position previously marked. Working towards the tip.
tack the deicer centerline to the leading edge of the propeller blade. Use tackifying solvent as necessary. If the
deicer is allowed to get off course, pull up with a quick motion and remove deicer. Recement per paragraph 14-
48. c and d if necessary before proceeding. Roll firmly along the centerline with a rubber roller. as show n in
Figure 14-17.
2.
Roll the tapered edges, especially the inboard edge, of the deicer with a narrow steel stitcher
roller.
CAUTION
To avoid damage to resistance wires, do not use metal stitcher on
body of deicer.
3.
Apply one even brush coat of sealer around the edges of the installed deicer.
4. Remove the masking tape from the blade immediately after applying the sealer.
5. Allow 12 hours cement curing time before turning up propeller. Allow 24 hours curing time
before operating the deicers. Handle the propeller carefully to prevent damage to the deicers.
b. Propeller deicers, one for each propeller blade, are supplied in B. F. Goodrich propeller deicing
system kits. Replacement deicers may be ordered from the B. F. Goodrich Company.
Reissued: 9/23/80
ACCESSORIES AND UTILITIES
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