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Bob Smith Industries |
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Go To Stocking Items | Go to Product Descriptions
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Using Cyanoacrylate Adhesives |
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Cyanoacrylates (CA) have become the adhesive of choice for
most hobby and household applications. High quality CA's, when used properly,
form bonds that in many cases are stronger than the material that is being
adhered.
CA's are reactive monomers that chemically link (polymerize) when pressed
into a thin film. The very thin layer of water moisture present on most
surfaces acts as an alkali, or weak base, which is the catalyst that results
in bonding; however, the presence of detectable amounts of water usually
degrades the performance of CA's.
With all CA's, the closer the parts fit together, the stronger the bond.
Always hold the bonding surfaces together as tightly as possible. Any rough
spots on the mating surfaces should be smoothed out. Although CA's will
hold objects together with considerable strength within seconds, the full
strength of the bond is not reached for several hours. Allow for this before
subjecting parts to maximum stress. Also, CA's are generally a little less
brittle and have a higher strength when they are allowed to cure on their
own.
Heat and moisture will decrease the shelf life of CA's. Unopened bottles
can be stored in a freezer or refrigerator, but allow them to reach room
temperature before using. Keep your bottles in a cool place that won't be
exposed to direct sunlight and store away from bottles of accelerators.
For the initial opening of the top, loosen the top first to relieve internal
pressure, then hold the bottle against a near vertical surface and cut off
the top 1/32" with a knife or razor blade without squeezing the bottle.
To prevent clogging, do not let the tip of the nozzle touch a surface that
has been sprayed with an accelerator. Before replacing the cap, sit the
bottle down hard to knock the remaining CA back into the bottle before squeezing
it in an upright position to blow air through the nozzle, then wipe the
tip clean. |
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Here's a run down of the Bob Smith line of CA's and their application: |
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INSTA-CURE has water thin viscosity that
wicks deep into joints by capillary action and cures in a matter of a few
seconds. Surfaces to be bonded must be tight fitting and should be held
together while you apply the CA around the edges of the seam. At the moment
CA's cure they give off a vapor that can irritate the nose and eyes, so
be prepared. Thin CA's work very well on balsa since they penetrate into
the wood and form more than just a surface bond.
INSTA-CURE+ is a higher viscosity CA for loose fitting
joints in which the adhesive must bridge gaps. Normally, the thicker CA
is applied to one surface and then the parts are held tightly together for
about 5 to 15 seconds. For large surface area, including those with close
fitting joints such as laminations, INSTA-CURE+ should also be used To prevent
premature curing, don't spread the glue into a thin film. Lay down a serpentine
bead with about 1" separations onto one surface, then assemble the parts,
letting the pressure spread the CA out.
MAXI-CURE extra thick CA is the best CA for most plastics,
including polycarbonates like GE Lexan. MAXI-CURE is the best choice for
plastic model assembly. When used with INSTA-SET, it works better than any
putty for modifying or filling voids. It can be carved with a knife or razor
blade and sanded and feathered to form a finish indistinguishable from the
plastic. MAXI-CURE bonds fiberglass, hardwood, metal and rubber better than
any other hobby adhesive.
INSTA-SET is a catalyst which acts as an accelerator that
allows CA's to quickly cure in thick layers. When a light mist of INSTA-SET
is sprayed on a surface to be bonded, it dries almost instantly, but remains
active for several minutes. Apply INSTA-CURE+ to the opposite surface and
the glue will set within a few seconds after the parts are held together.
To allow more time for the parts to be positioned correctly, wait to spray
the INSTA-SET around the glue joints after joining. This will instantly
hold the parts in place while the rest of the CA cures normally. A bead
of INSTA-CURE+ can be placed over a joint for reinforcement, then sprayed
with INSTA-SET. While INSTA-SET is compatible with opaque plastic and foam,
it may attack some plastics.
UN-CURE debonder will soften cured CA. If parts are bonded
incorrectly or your fingers are stuck together, a few drops of UN-CURE will
dissolve the CA in about a minute. If CA gets on any clothing, use UN-CURE
as a pre-soak before washing. Usually the fabric will come out as good as
new, although colors may be affected.
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Products Stocked
 | Insta-Cure Super Thin CA
 | 101 - 1/2 oz. $2.79 |
| 102 - 1 oz. $4.53
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| Insta-Cure+ Gap Filling CA
| 106 - 1/2 oz. $2.79
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| 107 - 1 oz. $4.53
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| Maxi-Cure Extra Thick CA
| 111 - 1/2 oz. $3.08
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| 112 - 1 oz. $4.98
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| Rubber Toughened AC - Stays Flexible
| 118 - 1 oz. $7.25
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| Insta-Set CA Accelerator
| 151 - 2 fl. oz. $4.53
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| Un-Cure CA Debonder
| 161 - 1 oz. $2.79
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We also have 5-minute epoxy.
These high quality CA's have a 24 month shelf life and come in a no-clog
bottle.
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