Epoxy need air to dry???

[Rocket Guy 1317]

I was just wondering does epoxy need air to dry? If it doesn't then I might as well glue on the recentering to my new rocket.

 

[m85476585]

No. In fact, many kinds of epoxy can cure under water.
Epoxy works by a chemical reaction. It's things that work by evaporation (like Elmer's) that need air.

 

[Stymye]

no ,epoxy hardens by chemical reaction rather than evaporation like wood glue does.

 

[SwingWing]

Yep, like they say above, no air needed. Also epoxy will weigh the same cured as it does in liquid form. (assuming you didn't foolishly thin it with solvent)

 

[by basher]

Does the heat produced aid the reaction (setting), or is simply a byproduct?

 

[Bill]

Originally posted by by basher
Does the heat produced aid the reaction (setting), or is simply a byproduct?

Both. The higher the temperature (within reason), the faster the cure and the shorter the working time.


Bill

 

[SwingWing]

Originally posted by by basher
Does the heat produced aid the reaction (setting), or is simply a byproduct?

Yes. particularly when epoxy is in a mass, such as in a cup. Heat produced will cause it to cure faster, causing more heat, causing....
It can get hot enough to produce smoke from a paper cup. It seems do this more when it is loaded with fillers, such as cabosil.
Look at a epoxy user guide for "exothermic reaction"

 

[cmmeyers]

I have a question....if you are using epoxy to secure some sort of weight in a nose cone (bb's for instance), will the generated heat melt a plastic nosecone? I'm about to do this for the first time to an Estes Phoenix nosecone.

 

[Rocketmaniac]

Originally posted by cmmeyers
will the generated heat melt a plastic nosecone?

If you add lots of epoxy, it can deform a nosecone, specially the ones that are thinner.

I have done the following to help reduce this heat. Fill a bucket or deep bowl with ice. Add water to make a very cold mixture. Put the nosecone in the bucket nose first and add the epoxy. Keep the nosecone in the buck until the epoxy dries. (I left it in there for quite a long time just to be sure)

 

[Rocket Guy 1317]

Okay thanks for the help. I'll try to post pictures of it later.

 

[noursh2002]

Does this mean that no matter how deep the mold is the epoxy will take the same hours to cure if the mold is not deep??

 

[hball55]

I have a question....if you are using epoxy to secure some sort of weight in a nose cone (bb's for instance), will the generated heat melt a plastic nosecone? I'm about to do this for the first time to an Estes Phoenix nosecone.

I would recommend a two-part expanding foam (closed cell) to secure weight in a nosecone. If you use epoxy, be sure to use sandpaper to rough up the nosecone first, otherwise you might have the epoxy and weight come loose and drop to the base of the nosecone; if in flight, that could prove disastrous.

As for an Estes plastic nosecone, clay should be good enough.

 

[Bill S]

I have a question....if you are using epoxy to secure some sort of weight in a nose cone (bb's for instance), will the generated heat melt a plastic nosecone? I'm about to do this for the first time to an Estes Phoenix nosecone.

I had this concern once too, and wasn't sure if it would be an issue or not. I solved it by putting the nosecone in a glass of water (note that the nosecone wasn't yet painted) and added the noseweight/epoxy to the nosecone, then put it in the water. No problems at all.

 

[Steve Shannon]

Does this mean that no matter how deep the mold is the epoxy will take the same hours to cure if the mold is not deep??

Your question contradicts itself. A deep mold will frequently result in epoxy cooking off, heating much more than usual to the point of melting molds and plastic mixing containers.
I just recently learned of extremely slow cure epoxies that are intended to be poured into a deep mold. They can take seven days to cure.

 

[mjennings]

I've seen a large quantity of 5 min epoxy light the paper mixing cup it was in on fire.

 

[kyle]

I would recommend a two-part expanding foam (closed cell) to secure weight in a nosecone. If you use epoxy, be sure to use sandpaper to rough up the nosecone first, otherwise you might have the epoxy and weight come loose and drop to the base of the nosecone; if in flight, that could prove disastrous.

As for an Estes plastic nosecone, clay should be good enough.

16 years later, I bet he's figured something out by now.

 

[hball55]

16 years later, I bet he's figured something out by now.

ROFL, I didn’t even look at the date of the post. I thought this was a new thread.

Just looked, he hasn’t been in here since 2009, and is probably out of the hobby.

 

[Sandy H.]

ROFL, I didn’t even look at the date of the post. I thought this was a new thread.

Just looked, he hasn’t been in here since 2009, and is probably out of the hobby.

Or he didn't mix the epoxy right and is still waiting on it to cure. . .

Sandy.

 

[BABAR]

Hope his epoxy has cured by now. I mean there is slow and there is sloooooooooooowwww.

 

[BABAR]

Or he didn't mix the epoxy right and is still waiting on it to cure. . .

Sandy.

Darn crossing posts. 16 years and I bump into 15 seconds!

 

[fyrwrxz]

Good advice never gets old. Unless you're a Doctor and the patient is already dead....

 

[Ez2cDave]

16 years later, I bet he's figured something out by now.

Not necessarily . . . LOL !

Dave F.