Epoxy?

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rocketman

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The instructions for the Loc Aura strongly recommend using epoxy- I've never used it before and want to ask the following:

Where should I get it (in the UK)?
Do you think that this would work?[/SIZE][/URL]
How do I use it?
About how much should I expect to pay for it?
How much should I buy?

Thanks in advance,

Tom:happydeer:
 
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Gillard

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Hi - i'm in the UK there are lots of suppliers, but if you are using it for general construction of the rocket, fins etc then i use araldite, most instructions recommend using 30 mins but i have used the rapid - 5 mins stuff on my highpower builds and have never had a problem, and there's less chance of a fin slipping (unless you are using a clamp etc.)
you can get it from everywhere, B & Q, wilkinsons, nearly all hardware shops and ebay.
if you are using the rapid, then make sure that everything has been dryfit tested first as rapid epoxy is unforgiving if a centering fin is a bit stiff in a tube.
hope this helps
 

rocketman

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Hi - i'm in the UK there are lots of suppliers, but if you are using it for general construction of the rocket, fins etc then i use araldite, most instructions recommend using 30 mins but i have used the rapid - 5 mins stuff on my highpower builds and have never had a problem, and there's less chance of a fin slipping (unless you are using a clamp etc.)
you can get it from everywhere, B & Q, wilkinsons, nearly all hardware shops and ebay.
if you are using the rapid, then make sure that everything has been dryfit tested first as rapid epoxy is unforgiving if a centering fin is a bit stiff in a tube.
hope this helps
Please can you post some links to epoxy that you would recommend (sorry, I'm terrified I'll end up with the wrong stuff!)
Thanks,
Tom
 

Zeus-cat

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Over here in the colonies all epoxy is labeled in big letter 5 Minute or 30 Minute or whatever. Even Mr. Magoo could pick out the right stuff the lettering is so large (see the attached photo).

I would add that temperature of the epoxy can be important too; at least witht the 5 minute variety. If it is cold it is very stiff and can be hard to mix. If it is very warm it can be very runny. In the winter it will tend to be on the cool side so it may be a bit stiff. The temperature also effects curing time. When it is cold it also can be closer to 2 minute epoxy. When it is hot out it can be like 10 minute epoxy.

Epoxy comes in two containers and you usually use equal amounts of the epoxy and the hardener. Do not get the kind that comes in two tubes with a single plunger. It is a royal pain to get out equal amounts with those things. Plus the risk of contaminating one tube with the other is high. Get the kind that comes in two seperate tubes. You just squeeze out equal amounts next to each other and mix it up. Whatever you mix it with and mix it on should be disposable as you will not get the unused epoxy off of them.

Epoxy.jpg
 

blackjack2564

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For a first time user I would recommend epoxy in the 10-12-15 minute range.

Depending on the brand availability those are the cure times you may have as your choice.

Using is simple. Mix 50/50 quantities from each bottle in a small container and mix thoroughly....1 minute should suffice. apply where needed.

5 minute cures very fast and you do not have much working time before it begins to set. Easy to waste a lot when new at this. Longer cure time lets you work at a less strenuous pace for a beginner.

Keep some denatured or rubbing alcohol handy for clean up and spills.

Ideal working temp is 65-80 degrees F. Cooler it can take much longer and warmer it will cure very fast.

Also when mixing it is better to have a larger surface area container or the epoxy can build up heat in the container and cure VERY fast if using large amounts. [better shallow and wide rather than small and deep]

Containers such as this 2oz cup are perfect for most applications. Lids off of all sorts of containers are commonly used.

Old Popsicle sticks, plastic fork handles, scrap wood dowels etc. can be used to mix. It is very important to mix your epoxy THOROUGHLY before using to assure proper cure.

BeforeandAfter003.JPG
 

loopy

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Isn't the LOC Aura paper tubes and plywood fins/rings? I'd use Titebond, personally. Rough up the surfaces a bit so it can soak in, and use Titebond II or III. All of my LOC rockets are built with wood glue, with the exception of the fin fillets where I used epoxy to make nice looking fillets. Using wood glue is PLENTY strong enough for this rocket. The body tube will delaminate before the wood glue bond is broken. My Expediter lawndarted from 2500 feet. All my fins were still rock solid on that thing, even though the rest of the rocket was completely destroyed. One fin was cracked in half from the impact, but the wood glue held firm. Much easier to use, cheaper, and just as strong on these materials.
 

Stymye

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a >>good<<< brand of 5 minute epoxy like Devcon runs in the 2000-2500psi range tensile strength. The hobby stuff is full of filler to allow for a 1:1 ratio so I would surmise it's not as strong as Devcon or Araldite


titebond I = 3,600psi

titebond II = 3,750psi

titebond III = 4,000psi

the numbers speak for themselves as far as whats the stronger glue ...especially for wood and paper construction.

if I were to invest in hobby epoxy I would go for atleast a 15-30 minute since it's the same price and right next to the 5 minute stuff.

all that said, 5 minute hobby epoxy is still strong for balsa wood
 
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ck101

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Professor downstairs to wait for answers
 

dave carver

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Professor downstairs to wait for answers

...is this what Google Translation would give me? I'm very pleased to see a member from China join our little group but these interpitations are amusing at least and possibly easily mis-interpited and given a wrong meaning.

I've got nothing against anyones country as long as they contribute to the information base I'm all for it. One of the dealers has a few Chinese plastic rockets, Long March and others, that are on my to-buy list.

I hope our communications get better and better as time goes on, who knows what we can learn from each other:)
 

rokitflite

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For 90% of the work I do (that requires epoxy) I use the Bob Smith 15 minute epoxy.
 

RimfireJim

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The temperature also effects curing time. When it is cold it also can be closer to 2 minute epoxy. When it is hot out it can be like 10 minute epoxy.
I think you mean the other way around. Higher temperatures accelerate curing of epoxy.

Do not get the kind that comes in two tubes with a single plunger. It is a royal pain to get out equal amounts with those things. Plus the risk of contaminating one tube with the other is high. Get the kind that comes in two seperate tubes.
Different strokes for different folks. Personally, I prefer the single plunger method for dispensing little dabs of epoxy. I think it is easier to get equal amounts. I store the syringe with the tip pointing upward so that any air bubble is at the tip - otherwise, if it is in the fluid it will compress and interfere with equal dispensing. Sometimes I have to add a little bias to one side or the other of the syringe but that doesn't bother me. The cap is keyed so that it goes back on only one way and I've never had a cross-contamination problem. I can see how two separate bottles would work better for mixing up larger batches, though.

Aren't forums great? You're guaranteed to get conflicting opinions! :D
 
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