Super Glue?!?!?!?!
Brian Rauchfuss - PCD
a wooden aircraft using superglue (cyranoacrylic, or however it is spelled).
It is an interesting idea, but I felt that the tests that were run were
inadaquate to prove the safety of the technique. Here are some more
tests that I would like to run:
1) Spruce to spruce: The test done in the article was spruce to plywood,
with the plywood failing first. Many important joints are spruce to spruce,
so it is important to make sure that the spruce will fail before the glue.
2) Flexibility: Wooden structures have flex. If the glue is too brittle then
it will fail over time.
3) Water and Gas resistance: Humidity is always with us, and gasoline spills
are always a possibility.
4) Long term durability: This is a difficult one to test, obviously, but
some clues can probably be gleaned from the tests that have been done on
CA glues since they were invented.
Any comments? I am thinking about sending this in to Custom Planes.
Brian
Buckwheat
Brian Rauchfuss - PCD <brau...@fm.intel.com> wrote in message
news:8ojfpk$a...@news.or.intel.com...
Just a couple of ideas that come to mind.
What was the quality of the CA they were using? Most CA's that I'm familiar
with are used for model airplanes and it's not cheap. The fumes from CA
glues are toxic and working with large amounts of it on a 1:1 size airplane
has to be a least a little dangerous.
Since you can take it off your fingers with Acetone based nail polish
remover your question about how might normal chemicals like fuel, oil,
paints, sealers, cleaners effect the strength of the CA is a good one?
The stuff is great for repairing Cessna, Piper, etc. interior plastic
though. Use the thicker CA and some fine fiberglass cloth (available at most
good hobby shops) to repair cracks in the plastic. Remove the piece from the
airplane (One drop on your nice seats or carpet won't come out.) and apply a
light coat of glue to the rear side of the piece. Then place a piece of the
fiberglass cloth on the glue. Using a sandwich bag or similar plastic cover
your fingers and rub the fiberglass cloth into the glue. Sand and paint or
cover with light interior fabric and it looks good. If you're real careful,
depending on the original damage, you might get a very clean joint and no
need to paint. Just watch the fingers and keep some nail polish remover
handy.
I'm sure some of the chemists can give us the dirty details about CA. ;-)
Owen Davies
idea of using superglue in aircraft work.
I can't answer any of them from experience, but the subject has come
up here before, and one reply to a similar question stuck in my mind.
It came from a long-time builder of model airplanes, who reported
that superglue worked fine, so long as you knew how to use it. He first
covered both pieces of wood with one of the very thin superglues, which
penetrated well into the wood. Then, before the glue had a chance to set,
he put one of the very thick, gap-filling superglues between the pieces,
clamped things together -- fairly gently, I suspect, to avoid excessive
squeeze-out -- and gave the assembly a shot of accelerator. The procedure
reportedly made joints that would last forever, even when the wood itself
was so soaked in fuel that you could squeeze liquid out of it like a sponge.
As for Brian's specific points:
Spruce-to-spruce joints -- Actually, I'd worry more about achieving sound
bonds to the plywood. Even if you sand the glaze off, I would expect it to
be
less easily penetrated by the glue than the spruce is. Any glue capable of
making a good joint with ply should bond to a softwood just fine. Of
course,
we all know how trustworthy reasoning is in the absence of experience.
Aside from that, I don't remember seeing many joints in any of the plans
I've looked at that didn't have a plywood gusset backing them up. Anyone?
Flexibility -- More potential for trouble here? I doubt those model
airplanes
tested the joints as hard as a full-sized plane would.
Water and gas resistance -- The model experience does seem to answer
this one.
Long-term durability -- Maybe ten years ago, an engineer friend of mine
tested cyanoacrylate/spruce/plywood joints in his heat/vibration chamber,
and they always failed eventually at the glue line. However, by the time
he heard about the thin-glue/thick-glue trick, the test equipment was
no longer available. He thought this idea might make a difference in the
results. I'd love it if someone could run the necessary experiments.
For whatever it's worth.
Owen Davies
Richard B
"Buckwheat" <arr12060...@mindsring.com> wrote:
>
> Brian Rauchfuss - PCD <brau...@fm.intel.com> wrote in message
> news:8ojfpk$a...@news.or.intel.com...
> > I just read an article in Custom Planes on the possibility of
assembling
> > a wooden aircraft using superglue (cyranoacrylic, or however it is
> spelled).
Not a chemist, but here's a few shots anyhow.
Cyanoacrylates are the strongest adhesives known to date. They are a
catalyst hardening process, and water is the catalyst. (This explains
why it sticks so well to fingers, but has problems with wood sometimes.)
They are relatively unaffected by most solvents, and even the acetone
takes a while to work on them.
Most will NOT fill a gap, and maintain any amount of strength, so an
absolute tight fit is required.
The stuff used for model airplanes is cheaper and less strong than the
industrial grades. The bottle that would cost $6 from the hobby shop,
would cost over $35 in the industrial grade.
It is brittle, and any wood that it penetrates into will also become
brittle. It's also heavy, in that there is no loss of weight as it
cures. Nothing evaporates, but it takes on a small amount of water
from the atmosphere.
Any oils on the surfaces will prevent it from penetrating, and
sometimes it won't cure where there is oil present.
The major problem with woods and ACC is that as soon as two surfaces
touch, it's bonded, whether you wanted it there or not.
I'm not saying it couldn't be used, but there are problems in it's use
that someday someone will overcome. Perhaps someway to make it more
flexible, a bit slower bonding time, etc. As it is, in a properly
prepared and fit joint, you will tear wood before breaking the glue.
Richard B.
Sent via Deja.com http://www.deja.com/
Before you buy.
Lars Steffenrem
about it.
Soft woods are the best places to use it. On harder woods epoksy is
usually better.
Cured CA has the properties of acrylic plastic (plexi) and is very brittle.
There are rubber thoughened versions that are better suited to vibrations.
It will not tolerate moist for longer periods, best way to loosen fingers
etc.,
are to use water and work the bond.
There are so many types available though, that I guess you can find one for
most applications. Watch out for isocyanates!
Some links:
http://www.loctite.com/catalog/category1.html?ProductLine=6010
http://www.gluguru.com/Cyanoacrylates/cyanoacrylates.html
http://www.usagoldca.com/
Lars
Tom "Hypnoser" Fitzgerald
PCD) wrote:
>I just read an article in Custom Planes on the possibility of assembling
>a wooden aircraft using superglue (cyranoacrylic, or however it is spelled).
>
>It is an interesting idea, but I felt that the tests that were run were
>inadaquate to prove the safety of the technique. Here are some more
>tests that I would like to run:
>
>1) Spruce to spruce: The test done in the article was spruce to plywood,
>with the plywood failing first. Many important joints are spruce to spruce,
>so it is important to make sure that the spruce will fail before the glue.
>
>2) Flexibility: Wooden structures have flex. If the glue is too brittle then
>it will fail over time.
>
>3) Water and Gas resistance: Humidity is always with us, and gasoline spills
>are always a possibility.
>
>4) Long term durability: This is a difficult one to test, obviously, but
>some clues can probably be gleaned from the tests that have been done on
>CA glues since they were invented.
>
>Any comments? I am thinking about sending this in to Custom Planes.
>
>Brian
Brian,
Not to show my age, But, If you have ever repaired your dentures with
CA you know it won't stand up to moisture for very long.
T0m "Hypnoser" Fitzgerald
Morgans
"Richard B" <ra...@my-deja.com> wrote in message
news:8ojlgi$240$1...@nnrp1.deja.com...
> In article <8oji0p$ptp$1...@slb3.atl.mindspring.net>,
> "Buckwheat" <arr12060...@mindsring.com> wrote:
> >
> > Brian Rauchfuss - PCD <brau...@fm.intel.com> wrote in message
> > news:8ojfpk$a...@news.or.intel.com...
> assembling
> > > a wooden aircraft using superglue (cyranoacrylic, or however it is
> > spelled).
>
>
> Cyanoacrylates are the strongest adhesives known to date. They are a
> catalyst hardening process, and water is the catalyst. (This explains
> why it sticks so well to fingers, but has problems with wood sometimes.)
>
> They are relatively unaffected by most solvents, and even the acetone
> takes a while to work on them.
>
> Most will NOT fill a gap, and maintain any amount of strength, so an
> absolute tight fit is required.
>
> The stuff used for model airplanes is cheaper and less strong than the
> industrial grades. The bottle that would cost $6 from the hobby shop,
> would cost over $35 in the industrial grade.
>
> It is brittle, and any wood that it penetrates into will also become
> brittle. It's also heavy, in that there is no loss of weight as it
> cures. Nothing evaporates, but it takes on a small amount of water
> from the atmosphere.
>
> Any oils on the surfaces will prevent it from penetrating, and
> sometimes it won't cure where there is oil present.
>
> The major problem with woods and ACC is that as soon as two surfaces
> touch, it's bonded, whether you wanted it there or not.
>
> I'm not saying it couldn't be used, but there are problems in it's use
> that someday someone will overcome. Perhaps someway to make it more
> flexible, a bit slower bonding time, etc. As it is, in a properly
> prepared and fit joint, you will tear wood before breaking the glue.
>
> Richard B.
There are CA glues for model airplanes that are slower, and will fill a
little more gap. I don't know about the flexibility, but my guess is , that
once they dry, they are just as brittle.
My objections, as posted before, would be the cost, and the fumes. Ever get
an eyefull of the fumes? Burn doesn't even begin to describe it.
Jim in NC
Richard B
"Morgans" <jsmo...@twave.junk.net> wrote:
>
>
> There are CA glues for model airplanes that are slower, and will fill
a
> little more gap. I don't know about the flexibility, but my guess
is , that
> once they dry, they are just as brittle.
Yes, and not quite as strong either
>
> My objections, as posted before, would be the cost, and the fumes.
Ever get
> an eyefull of the fumes? Burn doesn't even begin to describe it.
>
The fumes are partly hydrogen cyanide, which isn't really prone to
promoting health. The cost is about the same as any other premium glue
or adhesive, because you use so darn little of it to get the same
bond. "Model Aviation" had an article on it some years ago, and the
problem they were seeing was cyanide buildup in the blood stream, which
is something I'd try to avoid. It wasn't anything drastic, just a slow
deterioration that led to chronic fatigue. Fortunately, just staying
away from it for a while took care of the problem, and it left no
permanent damage. Great stuff for models, but I don't think it's
developed to the point that it could be used for full scale ships yet.
Owen Davies
> Not to show my age, But, If you have ever repaired your dentures with
> CA you know it won't stand up to moisture for very long.
Hmmm. My guess would have been that it wouldn't stand up to the
pressure of chewing. You put a lot of force on those choppers.
Probably a good deal more than any single part of an average
airplane would have to withstand.
Not that I'm trying to defend the use of CA. I have no intention of
ever trusting my tail to it, much less a passenger's.
Owen Davies
Tom "Hypnoser" Fitzgerald
wrote:
Owen.
force no boubt played a part however the failure was total and the CA
residue could easily be pealed off with you fingernail. FWIW.
Tom "Hypnoser" Fitzgerald
Richard Lamb
"clamp" while the epoxy was curing...
--
Richard Lamb
--
http://www.flash.net/~lamb01
Morgans
"Richard Lamb" <lam...@flash.net> wrote in message
news:39ADDA9B...@flash.net...
That is a tecnique with models, but where would you be willing to sacrifice
the strength in the bond line?
Jim in NC
pat...@my-deja.com
ac? Pat>
Orval Fairbairn
<lars.st...@c2i.netREMOVE> wrote:
Be VERY careful of aging properties of this stuff! I understand that it
degrades with time.
Bruce A. Frank
but it requires that an activator be sprayed on the surfaces first. It
is brittle and gets worse with age. There are "soft" versions, but the
methods used to soften the cured material contributes to a shorter bond
life. When working with quantity (more than one drop) very toxic fumes
are a problem. A half pint container was knocked over in our lab. The
fumes were so bad (eye and lung irritation) I had to don charcoal
canister respirator for cleanup.
--
Bruce A. Frank, Editor "Ford 3.8/4.2L Engine and V-6 STOL
BAFRANK(at)worldnet.att.net Homebuilt Aircraft Newsletter"
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