Epoxy




Epoxy

Kite Squid likes to buy Epoxy in the double barrel type syringe as the two parts dispense relatively equally so you donít have to measure the two parts and is available in most Wal-Mart type stores for about $2 which is a lot less expensive than purchasing at hobby shops.

Bill Bigge prefers to buy his Epoxy in large plastic bottles due to lower cost for volume and that is what he is used to.

Notes on epoxies:

Epoxies consist of a resin component and a reactive hardener component, both of which must be combined in the designed ratio for the resin to properly crosslink. The curing reaction of Epoxy is exothermic; meaning it will generate heat. The amount of heat generated will depend on a number of factors, but we must stress that you do not alter the amount of hardener to speed up or slow down the rate of cure, if you do, your Epoxy may never set. The rate by which Epoxy will cure is influenced by the masses involved, the rate of heat transition away from the Epoxy and by the ambient temperature. By mass, we are referring to the volume of material in the pot or mixing container. In other words, the more you mix the sooner the Epoxy will gel and the shorter will be the pot life. In hot weather it will be shorter also.

You may be able to mix in small batches or pour into a shallow tray or onto aluminum foil or plate to allow heat to dissipate to extend the pot life of the Epoxy. The resin may be heated or cooled before mixing to decrease or increase pot life respectively. Do this by placing the sealed container (of resin or hardener) into a bath of cool or heated tap water, as the case may be.

Once applied in a thin film, the curing rate is affected by ambient temperature. For each 18–20 degrees F. difference in ambient temperature, you can expect to halve or double the set time of the Epoxy. The pot life and cure times of the Epoxy system you use should be on the packaging or from the manufacturer. Some epoxies cure VERY slowly below a certain temperature and some not at all. Check the packaging….

Measuring and mixing Epoxy is critical to consistent success. The Epoxy must be mixed in the ratio directed by the manufacturer. (By volume or weight). Mix thoroughly for a full minute scraping the mixing tool and mixing surface making sure to get a thorough mix.

The shelf life of most epoxies is unlimited in closed containers. Some haziness and crystallization will occur if stored below 50 degrees F. for prolonged periods. This has no harmful effect on most Epoxy and may be alleviated by placing the closed container in hot tap water until the crystals dissolve.

Also you may decrease the viscosity of epoxies by warming the containers slightly before dispensing the epoxy. Be careful as this also can shorten the cure time. Do NOT heat in a microwave oven, just heat with hot tap water. Do not heat mixed epoxies.

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