Tamco

Tamco

Saturday, September 26, 2009

LIFTING

LIFTING

(Wrinkling, Raising, Alligatoring, Shriveling, Swelling)

The existing paint film shrivels, wrinkles or swells during new finish application or drying.

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CAUSE

(A) Solvents in a newly applied product attack the previous finish causing wrinkling, raising, or puckering of the paint film due to:

(1) Recoating enamels or urethanes that are not fully cured;

(2) Exceeding maximum flash or recoat times during application;

(3) Recoating a basecoat/clearcoat finish, where existing clearcoat has insufficient film build.



REPAIR

(1) Remove lifted areas and refinish.



PREVENTION

Check questionable finishes by rubbing a small inconspicuous area with a shop towel saturated with lacquer thinner. Finishes susceptible to lifting will soften, swell or shrivel as lacquer thinner is applied. If any of these reactions occur, the following recommendations should be considered.

(A) Do not exceed a product's maximum recoat time during or after application.

(B) Allow enamels or urethanes to thoroughly cure before recoating or attempting a repair.

(C) Avoid applying undercoats or topcoats excessively wet.

(D) Avoid the use of lacquer products over an air dried enamel finish.

(E) When insoluble material (enamel/urethane) has been applied over a soluble material (lacquer):

(1) avoid sanding through and exposing areas of the soluble material.

(2) apply two component primer surfacer and/or sealer as a barrier between the new and the old finish. When applying two component undercoats over soluble finishes, the complete panel must be coated.

(F) Use water borne undercoats to repair extremely sensitive finishes.

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