DeFelsko PosiTest AT-A Manuel D'instructions page 6

The decision of when to cut around a dolly is dependent on the
standard, specification, or contractual agreement to which the test
is to comply. The primary purpose for cutting through the coating is
to isolate a specific diameter test area. When the decision to cut
into the coating has been made, it is recommended to cut all the
way through to the substrate. As a minimum, it is suggested to
carefully cut away excess glue from the dolly application process.
This typically prevents a larger area of coating from being pulled
away from the substrate, resulting in a higher pull-off pressure.
Cutting Instructions
1. Cut through the coating around the edges of the dolly with
the included cutting tool, removing any excess glue.
2. Clear away any debris from the cutting process.
NOTES:
- Cutting may induce coating surface flaws such as
microcracking that may alter test results.
- For coatings with strong lateral bonding, it is recommended to
cut completely through the coating down to the substrate.
Drilling Template
When testing very thick coatings, the optional drilling template
may be preferred.
Prepare the Instrument
1. Push the actuator handle completely down into the actuator
assembly. Place the actuator over the dolly head and
attach the quick coupling to the dolly by reaching through the
holes in the actuator and lifting the coupling. Release the
quick coupling when the dolly head is completely engaged.
2. Press the
3. Verify Pull Parameters (pg. 10) are set to the preferred dolly
size, pull rate, pull limit and hold time. Change if necessary.
NOTE:
The 50 x 50 mm square dolly size is used for testing tile
adhesion and should NOT be used when testing with 50mm
round dollies.
Test Area Isolation
Pull-off Test
button to power-up the instrument if necessary.
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