Epoxy

[F_O_G]

is it ok to use elmers white glue in place of epoxy?

[ScaleNut]

yes , atleast on model rockets

[pyrovette20]

Why would you want to. I epoxy everything.

[Shreadvector]

Epoxy adds weight because it does not contain water that evaporates.

Heavy rockets can be unbalanced/unstable rockets.

Yellow wood glue is perfect for cardbaord, wood and paper. It will not stick to plastic and metal, but epoxy will.

[barone]

is it ok to use elmers white glue in place of epoxy?
Depends upon what you are bonding. Elmer's white glue isn't very good for plastic to plastic or plastic to wood or plastic to anything. If a plan is specifying epoxy for a construction bond, there is probably a reason for not using the white glue. What is the specific application?

[tfischer]

Another tidbit is that white glue and yellow glue are essentially the same thing, as far as adhesion is concerned. The difference is that white glue has a much longer "open" or "workability' time then yellow glue. I'm a woodworker, and most woodworkers prefer white glue due to the fact that things can be positioned, etc. rather than immediatly sticking. The final bond is the same strength.

With rockets, many people seem to prefer the yellow glue so that the fin (or whatever) will lock into place much sooner without having to be held forever.

-Tim

[ghrocketman]

Depends on the rocket power level whether white glue or Titebond will be enough.
As a rule I use Epoxy for fins and engine mounts for ANYTHING that will see "E" power and above.
Most likely overkill, but good insurance for mid-power rockets using engines from E through G.
Needless to say, for hi-power (H and above) epoxy is a must.

For run of the mill A to D power it just adds weight.

[Mach1]

is it ok to use elmers white glue in place of epoxy?

I'd use yellow carpenter's glue in place of the white glue. White glue will work, but the yellow is stronger. The bond of the yellow glue is much stronger than common model rocket materials anyhow.

Most of the time, (unless I have a special situation) the only time I use epoxy in model rockets is to secure the motor mount. A motor mount can be secured in with yellow glue just fine, but you will end up with a "pucker" ring on the outside of the body tube. The yellow glue shrinks when it dries causing the ring to appear.

[ScaleNut]

Another tidbit is that white glue and yellow glue are essentially the same thing, as far as adhesion is concerned. The difference is that white glue has a much longer "open" or "workability' time then yellow glue. I'm a woodworker, and most woodworkers prefer white glue due to the fact that things can be positioned, etc. rather than immediatly sticking. The final bond is the same strength.

With rockets, many people seem to prefer the yellow glue so that the fin (or whatever) will lock into place much sooner without having to be held forever.

-Tim

white glue is Polyvinyl acetate

wood glue is Aliphatic Resin

as far as the bond strength titebomnd III runs around 4000 psi and has a longer open time, it's stronger than gorilla glues !
white glue doesn't even enter the ballpark, however for balsawood it's plenty strong.

here's a prety good essay on glues from a woodworker site
http://www.woodcentral.com/russ/russ6.shtml

[tfischer]

white glue is Polyvinyl acetate

wood glue is Aliphatic Resin



There's a lot of conflicting information on this on the web, evidently. Some sites say "yellow glue is PVA". Others say it's "Aliphatic Resin". Still others say it's both...

I'm not a glue expert, but my quoted post above was how I understood things to be, at least until now that I'm bewildered... :confused: :eek:

I do know many woodwookers prefer white glue (PVA) due to it's long open time, and use it for things like gluing up table tops...

-Tim

[barone]

Tim....I wouldn't worry about it too much. I still haven't seen a post where the application was to be used that stated to use epoxy but he wanted to use glue... :rolleyes:

[tbzep]

Even "Elmers School Glue" is strong enough as long as you prepare the surface for it. Choose whatever glue you want based on its setting characteristics and start building.

I've always had balsa and/or paper breakage with the glue bond holding strong, regardless of white or wood glue. I've even witnessed HPR rockets built with wood glue that held together just fine...proving that the "person who's name shall not be mentioned" was right on at least one subject. :eek:

[F_O_G]

I got a rocket from http://www.artapplewhite.com/free.html and it says to fill the nose cone with 5-minute epoxy. I dont have epoxy and the white glue is what is available

[ghrocketman]

He probably wants the nose cone filled with epoxy because it needs nose weight of the epoxy to be stable.
You absolutely CANNOT use white/titebond glue to do this for two reasons:
1) it does not weigh anywhere near what the same mass of epoxy weighs.
2) white/titebond glue contains about 50% water by weight which evaporates leaving one with even less weight.

For this kit you must fill the nose cone with epoxy; if not available locally you will ned to order it and have it shipped to you.

[Royatl]

There's a lot of conflicting information on this on the web, evidently. Some sites say "yellow glue is PVA". Others say it's "Aliphatic Resin". Still others say it's both...

I'm not a glue expert, but my quoted post above was how I understood things to be, at least until now that I'm bewildered... :confused: :eek:

I do know many woodwookers prefer white glue (PVA) due to it's long open time, and use it for things like gluing up table tops...

-Tim

It *IS* both.

both are polyvinyl acetate emulsions (see the MSDS for each). The resins used in each are different for different properties (tackiness, set up time, weatherproofing). Even between the various yellow glues there are different resins, especially for the "weatherproof" ones.

[barone]

I got a rocket from http://www.artapplewhite.com/free.html and it says to fill the nose cone with 5-minute epoxy. I dont have epoxy and the white glue is what is available
Yep...alot of discussion about different glues but all miss the point of the original question. In this instance, you DO NOT want to use white glue or yellow glue. The epoxy in the nose cone is to add weight to the forward end of the model. There must be a stability issue with the model. Adding the weight at the nose moves the CG (center of gravity) forward to a point where it's in front of the CP (center of pressure) which in turn provides for a stable flight (assuming everything else is ok). If you don't have or can't get the epoxy, ask Art how much weight you are talking about and add the weight using modeling clay.

[Solomoriah]

I'm just about certain he's building a 13mm Six. I used 5 min. epoxy in all the ones I built or helped build, and in all cases the epoxy soaked through the 110# paper we were using, even though I've read online that 5 min. epoxy doesn't do that. Hah. The last one we built, we coated the inside with several coats of acrylic varnish before putting the epoxy in, but even that model has discoloration of the cone from the epoxy leaking through.

Flies great, but deployment is always an issue for us. Haven't had a non-lawndart landing yet (but the epoxy weight and strength means you get a nice hole in the ground :eek: ).

[F_O_G]

The instructions say not to use modeling clay in place of the epoxy and I am using cardstock.

[barone]

The instructions say not to use modeling clay in place of the epoxy and I am using cardstock.
Yep...you definitely don't want to use the clay with card stock..... :rolleyes:

[Solomoriah]

Oh, don't get me wrong... for that model (if, indeed, you are building a Six), you really have no choice but epoxy.

[F_O_G]

Oh, don't get me wrong... for that model (if, indeed, you are building a Six), you really have no choice but epoxy.

I am building a six (and I am NOT a he). I guess I'll just have to start over.

:) Does anybody have epoxy they can lend me? :)

[ghrocketman]

Lending Epoxy ay ????? :rolleyes:
That seems an awful lot like lending a facial tissue to me..... :D

[barone]

I am building a six (and I am NOT a he). I guess I'll just have to start over.

:) Does anybody have epoxy they can lend me? :)
I'm sure you have a Walmart near by. Look in the section near paints. Usually in the same row as the spray paints. You can pick it up for under $5. Can't remember what I paid (yea, I'm one of those OLD BARS :eek: ) but I think it was actually under $3.

[Royatl]

I'm sure you have a Walmart near by. Look in the section near paints. Usually in the same row as the spray paints. You can pick it up for under $5. Can't remember what I paid (yea, I'm one of those OLD BARS :eek: ) but I think it was actually under $3.


We don't know where she is in Montana so she might not be *that* near a WalMart.
Even so, epoxy should be obtainable in any local hardware store (but she could still be miles from her "local" store)

And she may be too young to just hop in the car and go get some.

[F_O_G]

We don't know where she is in Montana so she might not be *that* near a WalMart.
Even so, epoxy should be obtainable in any local hardware store (but she could still be miles from her "local" store)

And she may be too young to just hop in the car and go get some

Ha Ha

Montana is not that remote. Yes, there is a Wal*Mart here and it is only, like, maybe one mile away at the most.

I can drive, and yes, it is a car and not a tractor or a cow :D (although there are more here than there are people).

[barone]

I'm sure you have a Walmart near by. Look in the section near paints. Usually in the same row as the spray paints. You can pick it up for under $5. Can't remember what I paid (yea, I'm one of those OLD BARS :eek: ) but I think it was actually under $3.
Ha...quoting my own quote.... :D

Well, where I used to get it in Walmart has been changed since they've decided to re-arrange the entire store. It's now in the ailse with paint supplies and chaulk. Still in the paint section, just in a different ailse. Got to go down just about every ailse to find what you're looking for anymore. :(

[barone]

Ha Ha

Montana is not that remote. Yes, there is a Wal*Mart here and it is only, like, maybe one mile away at the most.

I can drive, and yes, it is a car and not a tractor or a cow :D (although there are more here than there are people).
Yeah...but in Montana don't they let you drive when you turn 12? ;) Cows in Montana? I always herd they had sheep there. :rolleyes:

[F_O_G]

Yeah...but in Montana don't they let you drive when you turn 12? Cows in Montana? I always herd they had sheep there.

Thats only on certain rez's where they don't really care. Where I'm at you have to be 14 1/2, take a driver's ed course, have a permit for at least a half a year, then have a restricted permit for a year (where you can only drive with one non-family person in the car) and then you can get your liscense.

And why are you talking about sheep? I only see those in the fairs.

Aren't there a bunch of rednecks in Tenessee?

And I think the epoxy is in the craft department, next to the paint department.

[barone]

And why are you talking about sheep? I only see those in the fairs.
Oh, you know those old TV shows where the cattlemen are all upset because the sheep herders are taking over the grazing lands..... :rolleyes:
Aren't there a bunch of rednecks in Tenessee?
Rednecks in Tennessee? You must be confusing this state with Kentucky....... :D
And I think the epoxy is in the craft department, next to the paint department.
Oh, so your craft department got moved towards paints? Now that makes sense. Men can shop in paints while the women shop in crafts and they are still within ear shot..... :eek:

[F_O_G]

Oh, you know those old TV shows where the cattlemen are all upset because the sheep herders are taking over the grazing lands.....

Are you talking about westerns? I strongly dislike westerns or country music or any thing that has something to do with cows.


Rednecks in Tennessee? You must be confusing this state with Kentucky.......

No, I am pretty sure I met a redneck from Tennessee who said there where other rednecks there.

Oh, so your craft department got moved towards paints? Now that makes sense. Men can shop in paints while the women shop in crafts and they are still within ear shot.....

Actually, our crafts section was always next to the paints, besides, it work better that way because you get something from crafts and just walk across the isle to pick out what color you want to paint it.

Aren't we getting a little off track from the main idea of this thread? First were talking about epoxy and now we're talking about Wal*Mart, Montana, Tennessee, and driving age.

Oh yeah, our Wal*Mart discontinued all the Rocket stuff :eek: !

[barone]

Oh yeah....epoxy......did you find it?

[Gus]

Oh yeah, our Wal*Mart discontinued all the Rocket stuff :eek: !
Well what's the point of living in "Big Sky Country" if you don't have rockets? ;)

Apparently your local WalMart manager has been sniffing the epoxy.

[F_O_G]

Well, I haven't had a chance to look for epoxy, and I probably would not be surprised if the Wal*mart manager was sniffing it. What does it look like anyway? Is it that one weird glue thats in the shiny tube-like bottle?

[barone]

Well, I haven't had a chance to look for epoxy, and I probably would not be surprised if the Wal*mart manager was sniffing it. What does it look like anyway? Is it that one weird glue thats in the shiny tube-like bottle?
Epoxy normally comes in a blister pack (hangs on a peg), Plunger type with two tubes attached. One tube has the resin and the other the hardner. It's designed so that as you push the plunger, equal amounts of resin and harnder are dispensed. Pay particular attention to the labels and get the correct type. There are 60 second, 5 minute, 30 minute, 1 hour, 2 hour varieties. That is basically the time it takes to set up (working time). Don't get the 60 second type......it sets too fast. by the time you've finished mixing, it's hard. :eek:

[Royatl]

Well, I haven't had a chance to look for epoxy, and I probably would not be surprised if the Wal*mart manager was sniffing it. What does it look like anyway? Is it that one weird glue thats in the shiny tube-like bottle?

Two tubes or squeeze bottles, different colors... one is usually marked "resin", the other marked "hardener".

In some cases it may come on a blister pack in a two-sided plunger, such that when you push in on the plunger, an equal amount of each side will be dispensed.

Dispense it on to soft plastic. Avoid paper or wood. Glass and metal are ok, but it will be difficult to remove the hardened excess.

In either case, once you have two equal amounts dispensed, you need to mix the two together well and quickly. Once they are completely mixed you will have a certain amount of time to work with it before it starts to harden, so only mix up the amount you need at that particular moment.

You'll probably waste a bit of it before you get the hang of it.

I would also recommend using latex or nitrile gloves handling it, as some people can develop a sensitivity to it, though occasional barehanded use is unlikely to hurt.

It does not get tacky (it's actually kinda oily), so you need some way of holding parts in place while it hardens.

[tbzep]

Devcon is the brand that most WalMarts carry. It's usually in a double syringe blister pack like this photo, but I've also seen it in a black cardboard box.

http://www.plastickitswholesale.co.uk/images/Products/GS31.jpg

[barone]

Devcon is the brand that most WalMarts carry. It's usually in a double syringe blister pack like this photo, but I've also seen it in a black cardboard box.

http://www.plastickitswholesale.co.uk/images/Products/GS31.jpg
Aaaahhhhh! A picture is worth a thousand words! ;)

[tbzep]

Aaaahhhhh! A picture is worth a thousand words! ;)

I do what I can. :p

BTW, here's the boxed version. I haven't seen it at my Walmart, but I've seen it in a few other places. I usually buy larger bottles of epoxy online so I haven't actually looked for any epoxy lately.

http://www.helsinkispeyclave.com/shop/images/Devcon5MinEpoxyIsokuva.jpg

[Gus]

Roy,

I'm curious why you say not to mix on paper? I mix small amounts on 3 X 5 cards and medium to larger amounts on paper plates. Somebody here in the forum mentioned using a post-it-type pad and he then just tosses the top sheet after each use, which also sounds convenient.

Other tips, keep paper towels and a bottle of rubbing alcohol handy in case you drip some epoxy where you don't want it. While the epoxy is still liquid it will clean up easily with rubbing alcohol.

Popsicle sticks, toothpicks, and bamboo skewers all come in really handy for applying epoxy.

In general, the curing time of the epoxy also equates to its strength. The longer it takes to cure the harder it will be. For most model rockets 5 minute epoxy is plenty strong enough. For high power centering rings and motor mounts 30 minutes and up is recommended by most.

[tbzep]

Two possible reasons: 1. It will soak through thin paper if it's long curing epoxy. 2. Fast curing epoxy gets nice and hot. It could burn you if you mix it on your bare leg, or could damage something else with the heat.....like that annoying cat. :D

I sometimes mix epoxy on a Cool Whip or margarine lid when I'm going to be mixing several batches. I also use paper, small dixie cups, cardboard, and glass. IOT, I use whatever I have handy. ;)

[Royatl]

Roy,

I'm curious why you say not to mix on paper? I mix small amounts on 3 X 5 cards and medium to larger amounts on paper plates. Somebody here in the forum mentioned using a post-it-type pad and he then just tosses the top sheet after each use, which also sounds convenient.



I say to avoid using it, not to *never* use it. Using small amounts on porous material invites some odd behavior, owing to some of the unmixed components being soaked into the paper (or wood). Getting a good mixture is much easier on a smooth non-porous surface; even better if the non-porous surface is flexible (so you can just pop the hardened epoxy off).

Also, a large amount of fast epoxy can get hot enough to burn a paper cup, or melt a plastic one! So avoid mixing epoxy in cups unless you're going to use the entire amount quickly.

[F_O_G]

Five pages later and I now understand the importance of epoxy, although it does look like something that would be in a doctors office.

[Royatl]

In fact your dentist is probably very knowledgable about certain types of epoxy as a lot of modern dentistry depends on epoxy compounds to make temporary fillings and such. My dentist often tells me about new molding techniques when I go in for an appointment.

[F_O_G]

So I'm guessing that epoxy is just as useful a duct tape.

[barone]

So I'm guessing that epoxy is just as useful a duct tape.
Well, duct tape will give you more drag on your rocket.... :D

[Gus]

The Discovery Channel did a whole episode of Modern Marvels on the subject of adhesives, and their impact on our lives. Really fascinating to see how dependant we've become on the amazing glues we've created.

[F_O_G]

Well, duct tape will give you more drag on your rocket....

My classmates said that stickers make the rocket go faster, and I'm guessing they are wrong. But that would be cool, a duct tape rocket :rolleyes: .

[barone]

My classmates said that stickers make the rocket go faster, and I'm guessing they are wrong. But that would be cool, a duct tape rocket :rolleyes: .
I've actually seen a model put together with duct tape. Actually, he used 2-liter soda bottles for the body (ducted taped together) :eek:

[ghrocketman]

Any classmate that would think stickers will make rockets go faster are the same kind of RETARDS that think slapping a big red R on a car will magically give it an extra 100 horsepower and super speed.
Total morons !

[slipstick]

I just built a 1/2A heli-roc (Apogee Kit) and used 15 minute epoxy from Hobby-town to glue on the balsa blades to the plastic hinges. I was surprised when the rocket fell over on the table and the glue joint (several hours old by that time) just came apart. The 1/16" balsa didn't break, it just came apart, the epoxy staying with the balsa. I doubt now whether the bird will survive a landing (the meets Nov 11).

I'm wondering how to reinforce the joint, maybe by laminating a thin piece of balsa on top of the hinge, sandwiching it between balsa.

Does Cynoacrylate attack epoxy resins?

[barone]

I just built a 1/2A heli-roc (Apogee Kit) and used 15 minute epoxy from Hobby-town to glue on the balsa blades to the plastic hinges. I was surprised when the rocket fell over on the table and the glue joint (several hours old by that time) just came apart. The 1/16" balsa didn't break, it just came apart, the epoxy staying with the balsa. I doubt now whether the bird will survive a landing (the meets Nov 11).

I'm wondering how to reinforce the joint, maybe by laminating a thin piece of balsa on top of the hinge, sandwiching it between balsa.

Does Cynoacrylate attack epoxy resins?
Does the plastic hinges have holes in them (where it meets the balsa)? Usually, the epoxy will act like rivets in the holes. I usually add a layer on the outside also, sorta like the sandwich effect you mention. I've never had a problem.

[F_O_G]

I just built a 1/2A heli-roc (Apogee Kit) and used 15 minute epoxy from Hobby-town to glue on the balsa blades to the plastic hinges. I was surprised when the rocket fell over on the table and the glue joint (several hours old by that time) just came apart. The 1/16" balsa didn't break, it just came apart, the epoxy staying with the balsa. I doubt now whether the bird will survive a landing (the meets Nov 11).

I'm wondering how to reinforce the joint, maybe by laminating a thin piece of balsa on top of the hinge, sandwiching it between balsa.

Does Cynoacrylate attack epoxy resins?

Use duct tape :D ! Just kidding, don't listen to me, go ask one of those old BARs.

[slipstick]

Does the plastic hinges have holes in them (where it meets the balsa)? Usually, the epoxy will act like rivets in the holes. I usually add a layer on the outside also, sorta like the sandwich effect you mention. I've never had a problem.

Yes there were holes and the epoxy extruded through to the otherside making little button heads. I tried putting on the rubber bands but the tension broke the joint off the others as well. I'm going to medium CA now.

[Royatl]

Yes there were holes and the epoxy extruded through to the otherside miking little button heads. I tried putting on the rubber bands but the tension broke the joint off the others as well. I'm going to medium CA now.

The ones I've built used CA and a few winds of very thin thread to serve as a mechanical bond.

[Gus]

I used CA Gel on the part of the hinge that connects to the blade. Has held up fine.

[moonzero2]

Duct Tape went to the moon.

[F_O_G]

What is CA?

[Ltvscout]

What is CA?
Short for Cyanoacrylate. Commonly known as crazy glue.

[F_O_G]

How do you pronounce that?

[Shreadvector]

"Soo-purr gloo"

:D


How do you pronounce that?

[tbzep]

"Soo-purr gloo"

:D

:p You took the easy way out. ;)

The big word is pronounced, sigh an oh ack ril ate

(ok......soo purr gloo) :D

[barone]

:p You took the easy way out. ;)

The big word is pronounced, sigh an oh ack ril ate

(ok......soo purr gloo) :D


Yeah...I like that....but sahy-uh-noh-ak-ruh-leyt is still soo-per gloo to me :rolleyes:

http://dictionary.reference.com/browse/cyanoacrylate

[F_O_G]

I did not get to go out of town but I did find epoxy at Wal*mart, just had to look in the hardware section instead of the glue.

[BatPlane]

Rocketeers,

I'm putting together a simple rocket using 5 minute loctite epoxy from Lowe's on engine mounts, fins, just about everything. http://images.lowes.com/product/converted/007934/007934081501md.jpg

The stuff seems oily when it hardens. Anybody else use this stuff? I'm trying to use equal amounts when I mix it but I did notice one "batch" didn't really harden. I'm guessing the resin to hardner ratio favored the resin too much. (user error!)

Any input, fellas? Is the paint gonna peel? Sorry to beat the subject to death. I'm trying to find the optimum glues and paints for these beauties.....something fun about mixing epoxy, spraying primer, sanding. etc....I think I'm addicted to building them!!!

[Solomoriah]

Incomplete hardening may indicate you didn't mix it thoroughly enough.

I've had problems with 5 min. epoxy being "oily" before... never seen the 30 min. or longer variety that way.

[BatPlane]

Incomplete hardening may indicate you didn't mix it thoroughly enough.

I've had problems with 5 min. epoxy being "oily" before... never seen the 30 min. or longer variety that way.

Well, the more models I build & more mistakes I make, the more I learn, I guess. I like the fact that the epoxy is so ridiculously strong. I hope it's sandable. I intend to sand with 600 grit paper and wipe down with alcohol before painting.

Use 30minute epoxy, mix more thoroughly....got it.

[barone]

Well, the more models I build & more mistakes I make, the more I learn, I guess. I like the fact that the epoxy is so ridiculously strong. I hope it's sandable. I intend to sand with 600 grit paper and wipe down with alcohol before painting.

Use 30minute epoxy, mix more thoroughly....got it.
Well, he wasn't really recommending 30 minute epoxy...at least I don't think so. 30 minute epoxy is good on everything though except maybe the fins. That's a long time to wait holding the fin in position. But, if you want to use it for the fins also, I'd suggest tacking the fins in place with CA and then applying the epoxy as a fillet.

[LeeR]

Well, the more models I build & more mistakes I make, the more I learn, I guess. I like the fact that the epoxy is so ridiculously strong. I hope it's sandable. I intend to sand with 600 grit paper and wipe down with alcohol before painting.

Use 30minute epoxy, mix more thoroughly....got it.

I prefer good old carpenters glue or white glue for bonding fins onto the body tube. If you want a tough fillet, then mix epoxy (15 minute or longer variety), thin a little with lacquer thinner or isopropyl alcohol (not rubbing alcohol!). Apply fillet, then rub the fillet with wetted finger (in a glove!) using the lacquer thinner or alcohol. This produces a thin, well-formed fillet, that does not need ANY sanding if done correctly.

I do not trust 5 minute epoxy -- I've never been happy with the results.

For gloves, I buy the 100 pack of the blue nitrile gloves at Harbor Freight. I've found them on sale for $5-6 for the box of 100. I also use these when applying wood stains, for polishing shoes -- lots of uses.

[sandman]

Incomplete hardening may indicate you didn't mix it thoroughly enough.

I've had problems with 5 min. epoxy being "oily" before... never seen the 30 min. or longer variety that way.

The "oily" is called amine blush and it's occurs when epoxy cures. It's normal but it must be removed before you paint!

The amine blush is really a kind of wax produced as a byproduct when the epoxy cures.

The faster the epoxy cures the sooner the amine blush comes out. On a large surface you really notice it.

Either sand it off or use soap and water. Really you have to remove it or you will have paint trouble.

I've probably gone through a few hundred gallons of West epoxy and I know about amine blush! I have to scrub it off before I can varnish.

I use to build wooden boats covered with fiberglass and West epoxy.

[Solomoriah]

I always use yellow glue to attach fins; for larger models, or those with short fin roots, I use epoxy for fillets. Just don't use enough that it can sag, and you're in business.

[BatPlane]

If you want a tough fillet, then mix epoxy (15 minute or longer variety), thin a little with lacquer thinner or isopropyl alcohol (not rubbing alcohol!). Apply fillet, then rub the fillet with wetted finger (in a glove!) using the lacquer thinner or alcohol. This produces a thin, well-formed fillet, that does not need ANY sanding if done correctly.

I do not trust 5 minute epoxy -- I've never been happy with the results.




The "oily" is called amine blush and it's occurs when epoxy cures. It's normal but it must be removed before you paint!


A whole lotta good info., boys! Much abliged! I did use alcohol to wipe everything down before painting the rocket & noticed the bottle said "isopropyl rubbing alcohol". Well, it seemed to work as the paint is adhering OK.

The epoxy seems like something I'm just going to have to get experience at using. It sure looks strong. Having a fin come off is annoying and this seems to be the remedy. I just don't see anything coming off if it's epoxied on!

Will send photos of the "epoxy rocket" when it's completed!! (gotta build it before the wife finds out I'm building rockets instead of painting the kitchen.)

[barone]

A whole lotta good info., boys! Much abliged! I did use alcohol to wipe everything down before painting the rocket & noticed the bottle said "isopropyl rubbing alcohol". Well, it seemed to work as the paint is adhering OK.

The epoxy seems like something I'm just going to have to get experience at using. It sure looks strong. Having a fin come off is annoying and this seems to be the remedy. I just don't see anything coming off if it's epoxied on!

Will send photos of the "epoxy rocket" when it's completed!! (gotta build it before the wife finds out I'm building rockets instead of painting the kitchen.)
Yep, them fins won't come off easily. But, what you will find, is that the body tube will unwrap :rolleyes:

[LeeR]

A whole lotta good info., boys! Much abliged! I did use alcohol to wipe everything down before painting the rocket & noticed the bottle said "isopropyl rubbing alcohol". Well, it seemed to work as the paint is adhering OK.

Hmmm -- I definitely got something wrong here. I think I meant denatured --basically you want alcohol that is not diluted with water. I use denatured alcohol to thin shellac. I'll have to try it with epoxy again just to make sure.

Rubbing alcohol has water in it, and that is OK for cleanup, but you want to avoid it when diluting epoxy.

I do know lacquer thinner works, and many cans say "For Thinning Epoxy". I've used it for years to thin epoxy, usually about 15-20% thinner to make it really spreadable.

Anyway, happy experimenting!

[F_O_G]

Its amazing that this post is still going on.

[barone]

Its amazing that this post is still going on.
What's amazing is that it's still going on and you probably haven't got your epoxy yet..... :eek:

[BatPlane]

]

Rubbing alcohol has water in it, and that is OK for cleanup, but you want to avoid it when diluting epoxy.

Anyway, happy experimenting!

Before I read all this, I actually did use epoxy fillets and with an isopropyl alcohol wet finger did smooth it out. I didn't use it to dilute, just smooth everything out. It seemed to work really well and kind of dissolved the wet epoxy a bit. Just painted the rocket....looks awesome! I did use isopropyl alcohol to clean off the dust after sanding. All AOK. I'm not worried about it. Hey, it IS just a cardboard rocket after all!!! (which will end up in a tree eventually :mad: )

Let's see, lesson learned: use denatured alcohol...got it!

Thought I'd keep this thread going :)

BTW: a friend gave me a serious high-performance rocket kit, a DG&A "Mini Sonik-Blast"

DG&A Rocket (http://www.rocketryplanet.com/content/view/935/99/)

I read about epoxy in the instructions & never considered it for these smaller Estes model projects. I may build the Sonik-Blast but doubt if I'll ever get around to flying that missle once it's built!...I'm a little too lazy to get FAA clearance for it!! :rolleyes:

[barone]

.... I may build the Sonik-Blast but doubt if I'll ever get around to flying that missle once it's built!...I'm a little too lazy to get FAA clearance for it!! :rolleyes:
Check around for a local NAR section. A lot of times they'll have launches that include the FAA waiver..... ;)

[BatPlane]

Check around for a local NAR section. A lot of times they'll have launches that include the FAA waiver..... ;)


Yeah, ya know once I do build it, I'm not going to be able to resist seeing it in action. I'll check with the friend who generously donated it to me once I complete it. Thanks.

[F_O_G]

What's amazing is that it's still going on and you probably haven't got your epoxy yet..... :eek:

Oh so true.

[BatPlane]

Just for the sake of a little comedy, I thought I'd add some more depth to the pondering of epoxy:

I flew my latest creation (assembled with almost 100% 5 minute Loctite epoxy) over 13 times Christmas day. On one ill-fated flight, the parachute didn't fully deploy causing a hard landing. Lo and behold, a fin came clean off! (Must have been the one I didn't mix enough!) No broken balsa, just epoxy popping it clean off.

I then put a "C" into another (assembled with 100% alphiatic resin glue) and the weirdest thing happened after apogee....the nosecone blew off and apparently the blast immediately blew open the chute ripping it completely from all but 2 shroud lines. It came down hard and again, a fin cracked clean off. No balsa was broken, only the glue joint.

Don't know what to think about what's the best adhesive, now....maybe a really carefully, thoroughly mixed 30 minute epoxy.



Anybody ever have a parachute blow out so forcefully, it blew it apart? That is exactly what happened to me.

Happy New Year, guys.

[CPMcGraw]

Just for the sake of a little comedy, I thought I'd add some more depth to the pondering of epoxy:

I flew my latest creation (assembled with almost 100% 5 minute Loctite epoxy) over 13 times Christmas day. On one ill-fated flight, the parachute didn't fully deploy causing a hard landing. Lo and behold, a fin came clean off! (Must have been the one I didn't mix enough!) No broken balsa, just epoxy popping it clean off.

I then put a "C" into another (assembled with 100% alphiatic resin glue) and the weirdest thing happened after apogee....the nosecone blew off and apparently the blast immediately blew open the chute ripping it completely from all but 2 shroud lines. It came down hard and again, a fin cracked clean off. No balsa was broken, only the glue joint.

Don't know what to think about what's the best adhesive, now....maybe a really carefully, thoroughly mixed 30 minute epoxy.



Anybody ever have a parachute blow out so forcefully, it blew it apart? That is exactly what happened to me.

Happy New Year, guys.

I've had them open explosively, such that I could hear the sound all the way down on the ground as if it were a gunshot. It's a direct result of using the wrong time delay, allowing the model to deploy (either ascending or descending) when the forward velocity is greater than about 25 FPS.

For most of our models, yellow construction glue (Titebond II, Pro Bond...) is more than sufficient in holding power, lighter weight (which is important), cleans up with just soap and water (also important), can be thinned with a drop or two of plain water (which is useful), cheaper (by a long shot!), doesn't irritate the skin (like epoxy)...

YCG just has far more positives than epoxy for most LP and even MP models. HPR is a different animal, with greater stresses in the flight envelope, so epoxy is the better choice there.

[Rocket Doctor]

What was the condition of the motor?
What type oif motor was it?
Would you consider it a "shotgun" ejection charge?
Fill out a MESS report and contact the motor manufacturer. (I assume it's an Estes)
You need to document this incident.
Happy New Year to all.

[BatPlane]

I've had them open explosively, such that I could hear the sound all the way down on the ground as if it were a gunshot. It's a direct result of using the wrong time delay, allowing the model to deploy (either ascending or descending) when the forward velocity is greater than about 25 FPS.



It was an Estes C6-3 which does happen to be the wrong time delay. I just checked and you're right. The C6-5 is the recommended engine, I used the wrong one. I don't think a report is warranted since it was my error. The engines that blew apart the parachutes looked like any other spent engine. Nothing unusual.

There was no gunshot sound that I recall. I did another set of flights yesterda y (gotta love this holiday time off :) )and the same thing happened with the same type rocket. It just blew the parachute apart (this actually saved the rocket because if the chute had deployed it would've floated into the trees. )

That is an interesting phenomenon, I never gave it much thought. If I'm following you, the thing was traveling too fast (In my case ascending) when the nosecone blew off and it should have actually deployed at the point of apogee where the rocket is momentarily weightless, correct?

[Solomoriah]

If I'm following you, the thing was traveling too fast (In my case ascending) when the nosecone blew off and it should have actually deployed at the point of apogee where the rocket is momentarily weightless, correct?
Motionless, actually. The standard rule is that the parachute should deploy at 30 feet per second or less.

[Mark II]

Even "Elmers School Glue" is strong enough as long as you prepare the surface for it. Choose whatever glue you want based on its setting characteristics and start building.

I've always had balsa and/or paper breakage with the glue bond holding strong, regardless of white or wood glue. I've even witnessed HPR rockets built with wood glue that held together just fine...proving that the "person who's name shall not be mentioned" was right on at least one subject. :eek:
I completely agree with you, Tim. A few months ago I built an Art Applewhite 38 mm Cinco. All of the airframe parts were made of foam board (really, really tough foam board, though). Because of this, Art recommended using only Elmer's Glue-All white glue for the construction, and that is what I used on mine. Since some of the joints are under considerable strain (did I mention that this foamcore board was especially tough?), I had to hold each joint together by hand for upwards of an hour until the glue had set enough to keep the joint from flying apart. But that was the only problem I had with using the Elmer's. I have flown the Cinco once on a Pro 38 1 grain, and there was absolutely no sign of any weakness in any of the joints. Granted, it has only had one flight so far, but the joints all still seem to be bulletproof. Bottom line: different glues are appropriate for different applications, and this is true of white glue, too. For gluing paper to paper, such as in construction of a paper rocket, or for a paper transition or shroud, for that matter, I won't use anything but white glue. Once it has begun to set, you cannot pull the two parts apart - the material will fail, but not the glue.

For the particular situation that prompted F_O_G's question, though, I would say to use the epoxy - the 5 minute formulation should work fine (I've built many of those rockets, and that's what I have always used). I don't think that white glue will work anywhere near as well for that particular need, and it will take forever to cure. (WG works best when it is applied in thin layers, but that's not what you'll be doing there.) These are my thoughts on the issue, anyway, for what they're worth.

Mark

[F_O_G]

Guys, I'm not even building that rocket anymore. :rolleyes:

[Mark II]

Guys, I'm not even building that rocket anymore. :rolleyes:
Details like that have never stopped anyone from posting on a thread in the past. ;)

But you're right; perhaps the issue has been fully played out...] <--CORRECTION: Scratch that!

Mark

[CPMcGraw]

If I'm following you, the thing was traveling too fast (In my case ascending) when the nosecone blew off and it should have actually deployed at the point of apogee where the rocket is momentarily weightless, correct?

More-or-less. As Solo said, motionless is a better term. And I would only modify his comment by saying "near motionless", as it's rare to get one to just "hang there" and tailslide. :D

I prefer to set my designs to achieve as low as possible a Dv number, as the lower you can get this value, the more gentle the deployment will be. When Solo says 30 FPS, he is talking about the upper limit for LPR recovery devices. You don't want your chute popping at 30 FPS more than once, because if it survives once, it won't usually survive twice.

When I say 'explosively', I mean it opens to a full-canopy condition in a fraction of a second, and this literally is enough to rip carpet thread through the tape disks on plastic chutes. It is more than enough to pop a single length of kite string, which some chutes are attached with. Sometimes you'll hear one of us talk about "reefing the chute", and this is a method of slowing down the speed of the canopy opening to full. A shirt button, with the shroud lines run through the holes, is one method. You push the button up to the bottom edge of the canopy before packing, and as the lines come taut under tension, the button prevents the canopy from snapping to full by dragging against the lines and 'throttling' the action.

It's far better to just "don't go there" at all, and keep the deployment speed as low as possible. Below 20 FPS is aggressive. Below 10 FPS is comfortable. Below 5 FPS is sweet. Below this is just more cream cheese icing on a pineapple-carrot cake...:D

[Solomoriah]

Huh. I was THINKING 20 but wrote 30. Brain fart.

[CPMcGraw]

Huh. I was THINKING 20 but wrote 30. Brain fart.

Just aim for the carrot cake...:D

[Mark II]

Just for the sake of a little comedy, I thought I'd add some more depth to the pondering of epoxy:

I flew my latest creation (assembled with almost 100% 5 minute Loctite epoxy) over 13 times Christmas day. On one ill-fated flight, the parachute didn't fully deploy causing a hard landing. Lo and behold, a fin came clean off! (Must have been the one I didn't mix enough!) No broken balsa, just epoxy popping it clean off.

I then put a "C" into another (assembled with 100% alphiatic resin glue) and the weirdest thing happened after apogee....the nosecone blew off and apparently the blast immediately blew open the chute ripping it completely from all but 2 shroud lines. It came down hard and again, a fin cracked clean off. No balsa was broken, only the glue joint.

Don't know what to think about what's the best adhesive, now....maybe a really carefully, thoroughly mixed 30 minute epoxy.
Also, make sure that you are applying your adhesive to a clean, dry surface. It helps to give the body tube a very light sanding (just enough to take the shine off) to remove the glassine coating and to give the adhesive more surface to grab onto. It sounds like neither the epoxy nor the yellow glue really ever achieved a bond to the body tube in the two incidents you cited, which is quite unusual since both adhesives normally work very well for attaching fins and both will produce very strong bonds.

Mark

[Mark II]

Lately, I have gone to using medium-cure CA, not just to tack the fins on, but to fully bond them on. For smaller rockets, I then add fillets of maxi-cure CA, smooth them down with a finger slightly moistened with acetone (or sometimes just dry, if I keep it moving fast). Once I have filleted all the fins, I spray them with a couple of shots of CA accelerator. For bigger rockets, I fillet with 30 minute epoxy. For my largest rockets, I use Aeropoxy structural epoxy, which will just about stop a bullet when it is cured, for both bonding and filleting.

F_O_G, you can't find a good cyanoacrylate adhesive at a hardware store or at Wal-Mart; you need to go to a hobby store to get it, or else order it online. For the same price that you would pay to get two or three 0.17 oz. tubes of Crazy Glue, you will get a 4 oz. bottle of hobby shop CA, and it will be much better quality, to boot. You will also have a choice of "fast" (or "super-thin", or "Insta-Cure") CA, "medium" (or "gap-filling") CA, and "slow" (or "Maxi-Cure") CA. (It is good to get a bottle of each.) That is also where you will find a good quality CA accelerator in an easy to use pump spray bottle (instead of in a tiny eye dropper bottle). You will also find better quality epoxy (again, in cheaper, larger bottles) there in various "speeds" or cure times.

Finally, there are a few different brands of high performance epoxy "systems" out there, too. Two of the best known brands are West Systems and Aeropoxy. These are a bit more expensive, but there is absolutely nothing else like them. Each system has its proponents in the hobby; as you might have picked up above, I'm a fan of Aeropoxy. You will probably not find either of these anywhere but online. You can get Aeropoxy at Giant Leap Rocketry or at Aircraft Spruce and Supply (Google to find their sites). You can get West Systems at Aircraft Spruce and a few other places. You will want to use one of these high performance epoxies if (or when) you move up to mid- or high-power rocketry, or if you are building a boat or an airplane in your garage. ;)

Mark

[F_O_G]

Details like that have never stopped anyone from posting on a thread in the past. ;)

But you're right; perhaps the issue has been fully played out...] <--CORRECTION: Scratch that!

Mark

I don't think every one is even on the same issue.

[barone]

I don't think every one is even on the same issue.
Well, you know, once a thread starts, the issues can change. Of course, usually, the thread starter would get everything back on track. So, where were we? :confused:

[F_O_G]

Five more posts untill there are one hundred posts, the most popular thread I have ever written and it's all (well, mostly) about epoxy. :D

[barone]

Here's what it has to say about epoxy.......

"They are strong, fast-curing, and universal in their bonding capabilities. They'll bond almost anything to anything else - except Teflon and some kinds of polyvinylchloride (PVC). Basically, epoxy is a plastic technically known as thermosetting."

Okay, four more......

[F_O_G]

Do you like my new user title?

...Only 3 more now...

[Solomoriah]

Well, don't look at me, I'm not helping you!

[F_O_G]

Help me how?

...99...

[F_O_G]

100!!!

[barone]

CI ;)

[Mark II]

"Every year is getting shorter never seem to find the time.
Plans that either come to naught or half a page of scribbled lines
Hanging on in quiet desperation is the English way
The time is gone, the song is over,
Thought I'd something more to say."

Mark
(Posting from my base on TDSOTM)

[Mark II]

"My my, hey hey
'Epoxy' thread is here to stay
It's better to burn out
Than to fade away
My my, hey hey."

Mark

(P.S.: " I'd like to take a walk
But not around the block
I really got some news
I met a man from Mars.
He picked up all my guitars
And played me traveling songs.")

[F_O_G]

Oh no, now people are singing (or trying to anyway) :D

[Mark II]

Oh no, now people are singing (or trying to anyway) :D
Just be grateful that this is a written dialogue; you really wouldn't want to hear me actually sing any of those lyrics! :eek: :D

Mark

[LeeR]

"Every year is getting shorter never seem to find the time.
Plans that either come to naught or half a page of scribbled lines
Hanging on in quiet desperation is the English way
The time is gone, the song is over,
Thought I'd something more to say."

Mark
(Posting from my base on TDSOTM)

I recognize a Pink Floyd song when I read it ...

(Changing topics, but before I go back, I saw Australian Pink Floyd about 2 months ago. Very impressive.)

So, to get back on topic:

I'm not a big fan of 5 minute epoxy. But that has probably been beat to death earlier For me, it is the 20-30 minute stuff only.

[F_O_G]

Guess what!!! I made it through the whole semester with out epoxy!!!! :D

[Mark II]

Guess what!!! I made it through the whole semester with out epoxy!!!! :D
Give that girl a pyrite star!!! ;)

Mark

[tbzep]

Give that girl a pyrite star!!! ;)

Mark

Hey, I used pyrite today for some density problems. Hmmm about 5 g/cm3 or about 20 g/cm3......which would you guys choose to have?

[barone]

Hey, I used pyrite today for some density problems. Hmmm about 5 g/cm3 or about 20 g/cm3......which would you guys choose to have?
Isn't the denser the better?

[tbzep]

Isn't the denser the better?

In this case, yes. Gold is about 19.32 g/cm3. I had the kids determining densities to find what was gold vs fool's gold. (too bad I didn't have any real gold for them to measure) :rolleyes:

With contest balsa, you'd want it to be just the opposite. ;)

[Mark II]

Hey, I used pyrite today for some density problems. Hmmm about 5 g/cm3 or about 20 g/cm3......which would you guys choose to have?
Whatever... Just don't get "fooled."

Mark

[ghrocketman]

Making it through an entire semester WITHOUT EPOXY is NOT something to be proud of.
I use epoxy EXCLUSIVELY for ANY build that will use real "E" (not those dud Estes E9's) power and above...probably overkill and heavy, but my rockets are almost always recovered with ZERO busted parts.

[F_O_G]

My rockets are just fine even w/out the epoxy.

[Solomoriah]

gh is a little, shall we say, serious about things. Anyone who puts an entire blog in his signature is pretty serious... :D

[Mark II]

My rockets are just fine even w/out the epoxy.
That may be true -- no one has any cause to doubt what you said. It is true that you can build perfectly good low power rockets (A - D) without the need for epoxy if you choose your materials carefully. I don't know whether your previous post about getting through the semester without needing to make use of epoxy was meant as a boast or just a statement of fact. None of the rockets that I built as a kid (all 5 of them) used epoxy, and all but one held up fine without it. The exception was my K-39 Semi-Scale Saturn V; I sure could have used some 5 minute epoxy for attaching those stupid glass/plastic fins :rolleyes: (the reasons are too involved to go into here).

So, F_O_G, good for you, and I really do mean that. If you keep building rockets, eventually you will run into a situation in which epoxy will be the most appropriate and optimal adhesive to use. When that happens, if you take a moment to recall the many good suggestions and items of advice that were given to you in this thread, it will serve you well. Please keep posting on this forum, because you do ask some very interesting questions. And see if you can post some pictures of your creations -- we would all love to see what you have built!

Mark

[ghrocketman]

Solomoriah,

ROFLAO !!!!!

:D :p

[F_O_G]

That may be true -- no one has any cause to doubt what you said. It is true that you can build perfectly good low power rockets (A - D) without the need for epoxy if you choose your materials carefully. I don't know whether your previous post about getting through the semester without needing to make use of epoxy was meant as a boast or just a statement of fact. None of the rockets that I built as a kid (all 5 of them) used epoxy, and all but one held up fine without it. The exception was my K-39 Semi-Scale Saturn V; I sure could have used some 5 minute epoxy for attaching those stupid glass/plastic fins :rolleyes: (the reasons are too involved to go into here).

So, F_O_G, good for you, and I really do mean that. If you keep building rockets, eventually you will run into a situation in which epoxy will be the most appropriate and optimal adhesive to use. When that happens, if you take a moment to recall the many good suggestions and items of advice that were given to you in this thread, it will serve you well. Please keep posting on this forum, because you do ask some very interesting questions. And see if you can post some pictures of your creations -- we would all love to see what you have built!

Mark

Barone keeps bringing it uup so I just decided to let you guys know that I didn't use it.

[barone]

Barone keeps bringing it uup so I just decided to let you guys know that I didn't use it.
Me? :D

[Mark II]

Barone keeps bringing it uup so I just decided to let you guys know that I didn't use it.
More power to you, F_O_G. I'm happy that everything worked out for you. Congratulations on your success! :)

Got pictures of any of your builds yet?

Mark

[F_O_G]

More power to you, F_O_G. I'm happy that everything worked out for you. Congratulations on your success! :)

Got pictures of any of your builds yet?

Mark

I do have pictures, but since school computors wouldn't load my digital camera, I used my teachers camera and she still needs to send them to me.