Epoxy ratio

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Well-Known Member
Sep 7, 2004
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what is the best resin to hardening agent for epoxy to use in mid power rockets?
Use what the epoxy manufacter recommends.

Or are you looking for an epoxy brand?
i was looking at uscomposites.com and they have different ratios of epoxy resin to hardener to resin and i want to know what works best for midpower rockets. i would also like to know whether or not i should use a filler and if i should what kind?
Generally 5 minute epoxy from Home Depot or Lowes will do fine for all your MPR needs.

Laminating composites is a different story though.
Personally, I would go with USComposites epoxy or West Systems. For one thing, they are a lot stronger. Second of all, the are a good deal for how much you get. Third of all, the pumps(not included) make it really easy to mix. Finally, you can add things like microbaloons that make it really easy to sand for fillets. For midpower, i think you would be fine with the 3:1 medium dry time. That would be plenty strong.
your saying just the 3:1 by itself wi
th no add ins for mpr right?
You dont need any additives, but microbaloons make it a lot easier to sand. They do not really add any strength though
wood glue is plenty strong for wood/cardboard parts and lighter
5 min epoxy might be good for making big fillets
but if you have a choice 15 minute epoxy would be a stronger glue for the same price as 5 min.
investing in west system/us composits for model and midpower rockets is quite an investment compared to a $3.00 bottle of wood glue.and a $5.00 set of hobby epoxy.

plus it saves you the money to buy more kits and motors.
what are you currently using for glues?
mostly wood glue and epoxy but im out of epoxy and almost out of wood glue. so i was wondering what i should get next