super glue=cement?

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rabidsheeep

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i just got my kits delivered, and im just wondering if super glue is considered "cement" or should i go get some special CA... or just reenforce it with white glue...

thanks

--sheeepster
 

rstaff3

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Depends what application/material and/or what link of cement was specified. The term cement usually in my experience refers to plastic cement. I have had good luck substituting CA for it, but don't have enough experience to say in general. If it's for plastic, I'd say get what they say and be sure.

More details might help.
 

rabidsheeep

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aerotehc mustang engine mount on the first page...

just got the mustang and aaruexaxasxexux (not gonna try :) ) so i wanna take my time and build them right...
 

Stymye

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..Aerotech suggests medium Cya..you could use epoxy of course...don't use the model cement too brittle..

you may have read this already but...sand those rings if they are too tight..or they can crimp the mm tube

good choice too ,very good kits, durable
 

dr wogz

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CA glue is 'super glue', otherwise known as Cyano-accrylate. It comes in a few viscosities: thin, medium, and thick. Thin dries / cures almost instantly, while the thick may take a minute to set-up.

You can aslo get a 'kicker' whic is usually a spray to 'instantly' cure teh CA glue.

But they are brittle. Ans the larger the gap, the weaker it'll be.

Keeping the CA bottle in the fridge will prolong it's shelf-life.

Epoxy is stronger, only in that is is not brittle, and somewehat plyable. Longer cure epoxy is stronger then 'quick cure' (5 minute) epoxy.

I would use teh CA to tack the fins in place, then use epoxy for the fillet. (or use white glue, or 'aliphatic resin' (yellow carpenter's glue) for the fillet)
 

firemanup

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My suggestion is following the directions and Med CA only on the build..

I know someone who went with epoxy and had problems because of it on an Initiator.. It adds un-needed weight and the kits are designed for building with the CA.

I've built 6 or 7 AT kits now and have had no problems with the CA holding fine on all of them. I think part of the reason for the CA is that the bond it provides is only JUST weaker than the fins..

Several people have had recovery problems with AT kits, tangled parachute or whatever, had them crash and the only problem is that a fin pops off, because of the fin lock system they can pop it right back in and fly it again instantly.

If you use epoxy and the bond is too strong instead of having just a fin pop, the fin breaks, now you're out of luck until you get a replacement fin from AT which could take weeks.

Mucho easier to just pop it back in..

My .02
 

Stymye

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need to clear up a few things there,

kicker will weaken cya's and make it brittle ...great for static plastic models ,not for rockets ,not sure why kicker is needed anyway,unless your in a heck of a hurry
I have 4 aerotech kits..built with med cya,,still going strong

also keeping cya in the fridge is a well distributed wifes tale ..moisture cures cya
(unless there is a specific brand that states that)

I used to keep mine in the fridge ...and I noticed that it actually diminished the shelf life ..compared to annother bottle I kept in a drawer..further investigation on the internet led me to that conclusion...

not being argumentive,,just posting from my personel experience.
 

DynaSoar

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Originally posted by rabidsheeep
i just got my kits delivered, and im just wondering if super glue is considered "cement" or should i go get some special CA... or just reenforce it with white glue...

thanks

--sheeepster
On the first page of instructions, right below the specs and pre-construction warnings and tips, it says:

"BUILDING INSTRUCTIONS (Use cyanoacrylate cement throughout)"

So, yes, by cement they mean CyA.

Some people use epoxy to glue the motor mount in place, because that gives them time to make sure it's placed properly before the glue sets. However, you're not supposed to glue the MMT in until after you've glued the fins on, so it's guaranteed to be straight anyway.

You *can* make epoxy to glob up on a long stick, and fillet the top of the motor mount inside the body once it's in place by placing it with the stick. Likewise, it's easier with epoxy to reach inside between the body and motor tube and add fillets to the joints. But according to AT, these aren't necessary.
 

dr wogz

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Your fridge is essencially a large dehumidifier anyways...
And Loc-tite brand do reccomend you "store unopened bottles in a cool dry place"

But to be honest, I've always used up a bottle before it 'expires'

And yes, soaking / loading on the kicker will weaken it. When it gets all white and 'snowy' you've used too much..

We use CA almost exclusivley in R/C plane contruction, as well as the odd bit of epoxy. Many planes, many manoeuvers, and all (most!) are still flying.. usually the wood breaks before the glue joint..
 

Stymye

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I bought 2 bottles of Flash brand medium..I put one un-opened in the fridge and forgot about it untill mabey 8 weeks later..

when I took it out ,1/3 of the bottle was gone I cut the tip and used some and noticed right away that it had become much thicker..after 2 weeks the remainder had solidified... once the bottle had warmed up I think condensation formed inside and caused it to harden.. example:take a beer out and set it on the counter it will be wet from condensation before long..

I am aware that loc-tite black recomends to be stored in the fridge..

like you said DR.W there must be a difference
 

karatekicker271

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I used CA on my mustang. I didn't use any epoxy, and fillets or anything and the only reason I dont have it anymore is because my dad lost it (I wasn't at the club at the time) it was a windy day, and he shot it up on a G-35...
 

shreadvector

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Just remember:

DO NOT "CYA" with CA.

Especially if you are about to sit down.

Another helpful hint from The Committee.

Originally posted by rabidsheeep
i just got my kits delivered, and im just wondering if super glue is considered "cement" or should i go get some special CA... or just reenforce it with white glue...

thanks

--sheeepster
 
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