Troubleshooting
tips
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Problem: Film coming off
when removing top mylar for development
Cause &
Trearment:
Moisture is not being removed from film after water
lamination. Use a blown heater or hairdryer to remove
moisture from film and improve adhesion. If you are not able
to get plate surface up to 180ºF then dry the plate for
much longer time than recommended. Humidity in shop may also
be too high, humidity should be 60% or lower. Plates can be
dried overnight without heat in proper humidity.
Problem: White, cloudy
spots forming under film after lamination
Cause &
Trearment:
Usual cause is contaminants. Powdered cleansers not rinsed
fully are also to blame. If problem persists, eliminate
powdered clenser and switch to a good metal polish, followed
by a high strength degreaser such as Right Stuff. Do not use
cleaners with orange oil or D-limonene. DO NOT SAND YOUR
PLATES. Sanding plates makes microscopic valleys and ridges
that can trap cleaners and prevent Puretch from adhering
because it may not let Puretch reach the valleys. This
method only works for thicker films and is not recommended
for Puretch. Sanding plates creates too much plate tone and
can also negatively affect resolution fidelity because
surface is roughened.
Problem: Not able to etch
small dots in hilghights
Cause &
Trearment:
Exposure too long. Shorten exposure and use a Stouffer
to determine exposure times. Do not adjust development time,
always keep this standard and adjust exposure instead.
Flourescents can cause this too, always use a point light;
one clear bulb light source from one point.
Problem: Film breaking
down during development
Cause &
Trearment:
Exposure too short, use a Stouffer to determine correct
exposure, do not adjust development time, always keep this
standard and adjust exposure.
Problem: Plate not biting
evenly
Cause &
Trearment:
Plate may be overexposed. See Stouffer info above. It
is also helpful to wet plate surface with Puretch developer
or soft water prior to placing in etch. The developer is a
slightly base solution and lets the etchant flow quickly
into the metal similar to how a spit bite medium works.
Plate may not have been hadled carefully after development,
do not touch plate surface with fingers after drying. Plate
may be oxidising from slow drying. A good way to dry plates
after rinsing is to blot surface with a clean piece of
newsprint, then air dry or hair dry. Etch that day if
possible to prevent oxidation of exposed copper.
Problem: Film not
adhering at edges of plate
Cause &
Trearment:
Do not bevel plates before lamination. A slight burr
from shear may cause an air pocket at edge, carefully knock
this off with a scraper or file without over beveling. Clean
back of plates around edges to keep grease, etc from
creeping in at edges. Always trim film from front side of
plate with very sharp blade. Do not prop plates on edge for
drying, this can cause delamming at that edge, dry flat
instead.
Problem: Small holes in
film and etch
Cause &
Trearment:
Dust and dirt particles in lamination or exposing unit.
Always work in a clean, dust free lamination room and close
off or filter air vents. Use compressed air on plate prior
to spray and lamination.
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