Bonding Procedure; Mixing The Adhesive - HBM EP 250 Instructions D'emploi

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Bonding procedure

4.1 Mixing the adhesive

The two components (resin and powder) of the EP 250 adhesive are packed
in a double bag, separated only by a plastic clip. For mixing the adhesive re-
move that clip first.
If the powder component of the adhesive should contain coarse particles it
might be difficult to mix it properly with the resin. Mixing of the adhesive
should rather be carried out as described below:
Unfold double bag then seize the two bags near to one end of the clip with fin-
ger and thumb and pull them apart, until the plastic rod drops from the clip.
Place the unfolded double bag on a plane support and press the resin onto
the powder component completely with the edge of the clip. If the resin cannot
be pressed completely from the bag the adhesive is no longer useable. Now
the two components shall be mixed completely be kneading. Having done this
the bag is opened at one end and the content is filled completely into a cup
which is supplied with the package.
Now stir the adhesive with one of the wooden sticks (included in supply) until
a uniform mixture is obtained, indicated by a uniform color of the mixture.
Slight warming in your hands will facilitate the process. Stir the adhesive care-
fully to minimize the number of air bubbles produced which can only escape
slowly due to the viscous nature of the adhesive.
Prior to using the adhesive for bonding strain gages spread a small amount
on the cleaned object slide and crush any powder clots that might still be pre-
sent and mix them carefully with the resin. Now the adhesive is ready for bon-
ding strain gages.
One double bag is sufficient for about 20 strain gages. The pot life is about 24
hours at room temperature. This can be increased by deep freezing at −35 °C
[ −31 °F] or lower to several months. To store the adhesive use a vessel which
seals it from the air. The vessel should be warmed to room temperature prior
to opening in order to avoid condensation of a water film on the surface of the
adhesive.
HBM
EP 250
A1659-1.0 en/de/fr