On Thu, 20 Jan 2005 14:02:17 GMT, the renowned "Tom Gardner"
wrote:

I have a situation that I need help with. I have a big bunch (3k) of
brushes that need better tuft retention for a special application. The
brushes are 7" long x 3-1/2" wide and have 50 holes/tufts in them. Each
hole is 1/2" deep x 9/32" dia. and each tuft is 3 flat wires bent 180 deg,
and stapled into the hole with a 18 ga., 1/4" crown x 1/2" leg staple. I am
thinking of injecting glue of some kind into the hole with the wire. These
brushes are already made. If I can inject glue or epoxy into the holes, the
material will have to be able to withstand the brushing action and not
crumble or pop out. I wonder if carpenter's glue would work. I'm looking
for leads for some type of powered dispenser too. My budget needs to be
under a buck apiece including labor.

Apparently, the action of the brush in this application is way different
than normal. They use the brushes in a linear motion that is parallel to
the staples. They use the sides of the flat wire to break spoo up rather
than the face of the flat wire to "sweep" like a normal use. This action
has a tendency to rock the staples out even though the tuft retention is
over 40 pounds pull-out strength. (Where's that Unabtaniun when I need it!)

There are air powered metering dispensers that can be mated with
automation to deliver the glue to each hole. I've been seeing them at
trade shows (the first part) for many, many years- there are now knock
offs. They can also be used to make no-tooling gaskets just by laying
down goop in an arbitrary pattern on a surface. And for making a kind
of keyboard. Popular with Asian manufacturers.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
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