{"id":1901,"date":"2010-01-27T14:21:14","date_gmt":"2010-01-27T22:21:14","guid":{"rendered":"http:\/\/rocketsnw.com\/?page_id=1901"},"modified":"2010-01-29T21:38:16","modified_gmt":"2010-01-30T05:38:16","slug":"curing-epoxy","status":"publish","type":"page","link":"https:\/\/northwestrocketry.com\/?page_id=1901","title":{"rendered":"Curing Epoxy"},"content":{"rendered":"

Article: 1901
\nBy Robert Krausert, January 2010<\/p>\n

Ever interested in techniques for curing epoxy? Here is a discussion that was captured from the RocketNW list server, and might help you when trying find methods to cure epoxy.<\/p>\n

Scott Barfield Asked:
\n<\/strong>Any of you guys ever built a tube curing oven? I am looking for info on temp control circuits.<\/p>\n

Sam Grado Responded:<\/strong>
\nLook for used laboratory equipment, specifically clinical lab equipment. I have used a lab incubator as a curing oven for 5 years. They offer excellent temp control & monitoring and are about the size of a large mini-fridge. They usually come with a clear door (poly or tempered glass). I bought mine for $125.00.<\/p>\n

Greg Clark Responded:
\n<\/strong>I used a temperature switch that I got at the local appliance repair shop.\u00a0 I think they’re used to turn on and off the heat in things like clothes dryers.<\/p>\n

Like this: http:\/\/www.thermodisc.com\/productdetail.asp?ProductID=17<\/a><\/p>\n

Or you could build this!!!<\/p>\n

http:\/\/www.sparkfun.com\/commerce\/product_info.php?products_id=81<\/a><\/p>\n

Marty Weiser Responded:<\/strong>
\nI just adjust the heat source and any venting to get the temperature I want in mine.\u00a0 1″ foil faced foam panels that are held together enough to not fall apart and a 300W light bulb gives about 150F in a 2′ x 2’x 4′ oven. Taping the seams and weighting the lid would increase that a fair bit as would using 2″ thick foam.\u00a0 But it would be harder to break down and store.<\/p>\n

Bob Yanecek Responded:<\/strong>
\nI used 1″ foil covered foam to make an oven 2′ X 2′ X 6′ then added a ‘milk house’ style heater that has a built in (but uncalibrated) thermostat. While temperature comes up fast, it takes me about 10-15 minutes of fiddling to adjust the thermostat to achieve any particular stable temperature (max is about 180 deg F).<\/p>\n

Greg Deputy Responded:
\n<\/span><\/strong>My favorite setup was the guy’s who took a standard electric oven, then added a fan and a foam box on the front.\u00a0 Automatic thermostat, as well as timer.\u00a0 If you have the space and a 220v outlet, you can find old electric ovens for free or close.<\/p>\n

Andrew MacMillen Responded:<\/strong>
\nI did pretty much the same, but over the top, and longer for hybrids \ud83d\ude09 I thought I’d shared this back when, but don’t see it.<\/p>\n

http:\/\/www.macmillen.com\/rocketry\/cure_oven\/<\/a><\/p>\n

Greg Deputy Asked:<\/span><\/strong>
\nIs 170 hot enough?\u00a0 The epoxy I have wants a post cure to 250, but maybe I just have something weird…<\/p>\n

Andrew MacMillen Responded:<\/span><\/strong>
\nI use System Three T88 general purpose epoxy. I cure it at at 90F, which will cure in 3 hours but I usually stop at 2. Once my air frame section section is done, I post-cure at 120 for 1 hour to finish all the cross-linking, and maybe some inter-layer bonding. T88 has a max service temp of 160F, so I stay well below that to prevent de-linking.<\/p>\n

System Three & West Systems are both marine oriented, so are lower temp than Aeropoxy. It’s ‘glass’ temp is around 200F, so even it shouldn’t go over 150F where it looses 90% of it’s strength. I think some of that may be recovered when cooled.<\/p>\n

High temp special epoxies like the one ShadowAero used to carry, prepreg cloth, etc are a whole different story.<\/p>\n

Andrew MacMillen Added:<\/span><\/strong>
\nOne other note: elevated temps don’t allow as much penetration. That’s not so critical if you’re laminating over peeled cardboard or making standalone composite tubes. But it is a factor for bond strength at centering rings, fin roots, couplers, etc. where 75-80F for the initial cure might be better.<\/p>\n","protected":false},"excerpt":{"rendered":"

Article: 1901 By Robert Krausert, January 2010 Ever interested in techniques for curing epoxy? Here is a discussion that was captured from the RocketNW list server, and might help you when trying find methods to cure epoxy. Scott Barfield Asked: Any of you guys ever built a tube curing oven? I am looking for info […]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":1903,"menu_order":0,"comment_status":"open","ping_status":"open","template":"","meta":{"ngg_post_thumbnail":0},"_links":{"self":[{"href":"https:\/\/northwestrocketry.com\/index.php?rest_route=\/wp\/v2\/pages\/1901"}],"collection":[{"href":"https:\/\/northwestrocketry.com\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/northwestrocketry.com\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/northwestrocketry.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/northwestrocketry.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1901"}],"version-history":[{"count":5,"href":"https:\/\/northwestrocketry.com\/index.php?rest_route=\/wp\/v2\/pages\/1901\/revisions"}],"predecessor-version":[{"id":1915,"href":"https:\/\/northwestrocketry.com\/index.php?rest_route=\/wp\/v2\/pages\/1901\/revisions\/1915"}],"up":[{"embeddable":true,"href":"https:\/\/northwestrocketry.com\/index.php?rest_route=\/wp\/v2\/pages\/1903"}],"wp:attachment":[{"href":"https:\/\/northwestrocketry.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1901"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}