Epoxy Question
Ken W. Alger
experiences others have with epoxy for the various portions of the build.
Specificially, what epoxy time should I be looking for to use for the motor
mount, fins, filets, couplings, bulk heads, etc. I have heard a multitude
of different suggestions locally and would like to know what this group
thinks.
Also, what is the link for West Systems, I have heard good things about
their products but cannot seem to find other information or a good source to
purchase their system.
Thanks,
Ken
Bobby B
I am also new to HPR and built my Aerotechs with 5 min epoxy. I am careful
to prep all surfaces with light sanding and then clean off the sanding dust.
If you are building Aerotech kits make sure you clean the fin surface that
meets the body tube, some of my fins had a small amount of "flash" that
prevented intimate contact. I have 8 flights in so far with some maximum
power engine sizes in each rocket and all is well with the epoxy
connections.
I was advised by one model shop not to use 5 min. because the it was not as
good as 90 min epoxy.
I bought both... I did my own test... I cannot tell the differance in
strength after curing.
When working with 5 min epoxy you do need to be quick about assembly... if
it starts to gum up before your done , you need to be mixing more
QUICK.......
Last hint, I go to the just a buck store and stock up on cheap brushes, the
long wooden handled ones with 1/8 to 1/4 brush width. I use these to "help"
the epoxy into the joints and make "clean" looking glue joints....not works
of art but a bit better than a 1/8 dowel point.
I hope this helps.....
Bobby B
"Ken W. Alger" <kena...@home.com> wrote in message
news:YD4X6.191117$p33.3...@news1.sttls1.wa.home.com...
Gene Costanza
the premiere epoxies for rocketry, but don't discount
http://www.systemthree.com as it too has been lauded by many here (and has
an occasional appearance here by someone "on the inside").
Dollar for dollar, the West and System Three products are cheaper than small
volumes of other types, notably NHP and Bob Smith (two very good brands
also), but the West and System 3 products are inherently more sandable. I
believe you can order reasonably-priced "starter kits" from either source.
One thing you MUST be a ware of in re to epoxies: SMALL amounts, properly
applied to pre-prepped, have IMMENSE strength. SO LESS IS MORE!!!!!!!!!!
Save on dead weight with no loss in application.
If you want a REAL brain-fryer, go to:
http://www.matweb.com/SpecificMaterial.asp?bassnum=O1770&group=General
--
METRA BOD TRA #07017 L3 NAR #74503 L3
I give in to sin,
Because I like to practice what I preach...
"Ken W. Alger" <kena...@home.com> wrote in message
news:YD4X6.191117$p33.3...@news1.sttls1.wa.home.com...
Jim Yanik
<YD4X6.191117$p33.3...@news1.sttls1.wa.home.com>:
I'd like to suggest that you get a System Three epoxy trial kit,for a
whopping 10 bucks,postpaid.You get a fair amount of epoxy,several fillers
to experiment with,a sq.yard of glass cloth,and some cups,spreader,mix
sticks,and the very useful and informative Epoxy Book.This is a really good
deal. Only 10 BUCKS!!!!
www.systemthree.com -and they take charge cards.
The usual disclaimers.
--
Jim Yanik,NRA member
remove X to contact me
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ssin
strength and light weight. it is best to go to wal-mart or this type of
store it is usually in the automotives section of the store there r many
types there.
the have a stick type, black in the middle gray on the outside(do NOT get it
cause it sux)
they have one that looks like two sryinges side by side guess what(it sux
too.)
get the one that is two seprate tubes.
one is the weld agent the other is the hardening agent. by geting the 2
seprate tubes you can play with the mixture a bit.
it's usually done with a 50-50 mix(best guess) but if u find it takes too
long to harden then on the next bit u mix make it 40% weld 60% hardner
this will make it go rock hard in five minutes don't go above 60% hardner
cause it will flake easily if you go under 50% with the hardner then it
takes a long time to set if u go under 40% then it will not harden enough.
sounds hard? not at all just try it and you'll never go back to glue.
hope this helpes
ssin
--
"Jim Yanik" <jya...@kua.net> wrote in message
news:90C459A75j...@209.25.157.130...
Chuck Pierce
wrote:
<snip>
>get the one that is two seprate tubes.
>one is the weld agent the other is the hardening agent. by geting the 2
>seprate tubes you can play with the mixture a bit.
>it's usually done with a 50-50 mix(best guess) but if u find it takes too
>long to harden then on the next bit u mix make it 40% weld 60% hardner
>this will make it go rock hard in five minutes don't go above 60% hardner
>cause it will flake easily if you go under 50% with the hardner then it
>takes a long time to set if u go under 40% then it will not harden enough.
>
>sounds hard? not at all just try it and you'll never go back to glue.
>
>hope this helpes
>
>ssin
Whoa! Adding extra hardner doesn't make the epoxy set up more
quickly. It usually does the opposite. Extra hardner often keeps the
epoxy from fully curing at all. A little extra epoxy is more
forgiving than a little extra hardner. If you want the epoxy to set
up more quickly, get faster curing epoxy; don't play with the mixture
ratio. Giving advice like this to novices is bad news, especially if
they are building their first high-power bird.
Chuck
--------
Chuck Pierce
NAR 78629, Level 1
cpierce_AT_knology.net
Tim Sapp
JB Weld. But I agree, thats not a good idea with epoxy. I have a motor
mount here that I messged up on that has set for a month or so and it's
still a bit tacky and I can pull strips of it iff with my fingers.
Follow what the manufacture states on the empxy parts.
--
Tim Sapp
Sr. Advisor
Dallas Area Rocket Society (DARS) #308
NAR 78738 -- L2
"Chuck Pierce" <cpierce....@knology.net> wrote in message
news:sadsitg1frjdibi5h...@4ax.com...
Mark Recktenwald
news:sCpX6.5133$rA2.1...@news-rep.ab.videon.ca...
> <snip> it is best to go to wal-mart or this type of
> store it is usually in the automotives section of the store there r
many
> types there.
I once thought that way too. If all you are doing is building *one*
medium-sized large model rocket, you may be saving money (in a
short-term sense) but you are spending way more "dollars per ounce of
epoxy" than you need to. As soon as you buy one or two more of these
"hardware store epoxies", you have spent close to $10 and all you have
to show for it are a few epoxy joints
Jim's suggestion to get the $10 System Three trial kit is by far the
better way to go. You get much, much more epoxy (by itself worth the
$10), plus all of the other goodies Jim mentioned. Now you're glassing
that Fat Boy, thickening your epoxy for run-free fillets, the list goes
on.
Go to:
http://www.systemthree.com/index.html
and click on the link to "TRIAL KITS".
Call the "800 number" and place a credit card order, or print out the
order form and mail it in with a check or money order.
--
Mark Recktenwald
Stow, Ohio
Moderator of ABMR on Yahoo! Groups: http://groups.yahoo.com/group/ABMR
NAR #77432 L1, MTMA (#606) Advisor
MTMA web page: http://web.raex.com/~markndeb/rockets/mtma/
tdstr
Mark Recktenwald wrote:
>
> "ssin" <ssi...@hotmailNOSPAM.com> wrote in message
> news:sCpX6.5133$rA2.1...@news-rep.ab.videon.ca...
> > <snip> it is best to go to wal-mart or this type of
> > store it is usually in the automotives section of the store there r
> many
> > types there.
>
> I once thought that way too. If all you are doing is building *one*
> medium-sized large model rocket, you may be saving money (in a
> short-term sense) but you are spending way more "dollars per ounce of
> epoxy" than you need to. As soon as you buy one or two more of these
> "hardware store epoxies", you have spent close to $10 and all you have
> to show for it are a few epoxy joints
>
> Jim's suggestion to get the $10 System Three trial kit is by far the
> better way to go. You get much, much more epoxy (by itself worth the
> $10), plus all of the other goodies Jim mentioned. Now you're glassing
> that Fat Boy, thickening your epoxy for run-free fillets, the list goes
> on.
>
> Go to:
> http://www.systemthree.com/index.html
> and click on the link to "TRIAL KITS".
>
> Call the "800 number" and place a credit card order, or print out the
> order form and mail it in with a check or money order.
I did just that and I must admit, the System3 trial kit is the perfect
way of getting aquatinted to pro-epoxy techniques. The epoxy booklet
you receive with the kit is fantastic as well. There should be enough
epoxy to build several complete rockets. I did my LOC Legacy and there
is plenety left for at least another 3-4 medium sized rockets.
Interesting enough it looks like Raka has a similar offer at $10. I
just ordered mine today. Unlike the System3 trial kit the Raka
includes both slow and fast hardener.
Mr. Dave Urbanek deserves kudo's for pointing me to these sites.
http://www.raka.com/epoxypri.htm#KIT
Ted Novak
TRA#5512
Jamey #5295
thi kin
wit too toobs.......wurcs ril gud to..........
Anonymous posters post more crap .....:^)
Poly-poxy, Aeropoxy, great for laminating, Devcon great for construction.
Jamey #5295
"ssin" <ssin22@MORE CRAP.com> wrote in message
news:sCpX6.5133$rA2.1...@news-rep.ab.videon.ca...
Jim Yanik
<sCpX6.5133$rA2.1...@news-rep.ab.videon.ca>:
For little rockets,I use yellow wood glue or the exterior gel wood
glue(nice fillets,no runs),for bigger,mid-power rockets,epoxy-glass. If you
are glassing BTs,you want to use a thin epoxy and the S3,West and Raka are
among the best,IMO. Raka has the best prices.
Jim Yanik
<3B2E50BC...@foadspammervisi.com>:
The RAKA 1.5qt kit of epoxy is priced better,also.
Bob Kaplow
> when i build rockets i will use nothing less than epoxy because of it's
> strength and light weight. it is best to go to wal-mart or this type of
> store it is usually in the automotives section of the store there r many
> types there.
AAACKKK! You're much better off with a professional marine (systemthree,
west) or at least hobby shop grade epoxy than anything found in a walmart,
supermarket, hardware store, or the like. The same is true for CA adhesives.
Avoid anything sold in mass market stores.
I too recommend folks start with the System Three sample kit, 'cuz you get
everything you need and a great instruction book, all for a measly $10. You
can even get the book for free, from their web site, in PDF format.
Bob Kaplow NAR # 18L TRA # "Ctrl-Alt-Del"
Kaplow Klips & Baffle: http://www.nira.chicago.il.us/Leading_Edge/MayJun00.pdf
NIRA: http://www.nira.chicago.il.us NAR: http://www.nar.org
"We find that adult supervision stifles our natural creativity" J. Fox 4/27/01
>>>>> Boycot Yahoo's censorship! <<<<<
The only thing truly indecent or offensive on the Internet is censorship.
Mark Simpson
Be careful when you make such sweeping comments like your first statement
below. I can think of several common applications in which wood glue
outperforms epoxy by orders of magnitude at a fraction of the weight. In fact,
I build most of my HPR stuff with wood glue and I've never had a shred or any
structural failure. I, also, tend to build most of my rockets from Kraft tubing
and plywood. When I use plastic, phenolic and G-10, I use epoxy.
Mark Simpson
NAR 71503 Level II
Bill Nelson
: Ssin,
: Be careful when you make such sweeping comments like your first statement
: below. I can think of several common applications in which wood glue
: outperforms epoxy by orders of magnitude at a fraction of the weight. In fact,
: I build most of my HPR stuff with wood glue and I've never had a shred or any
: structural failure. I, also, tend to build most of my rockets from Kraft tubing
: and plywood. When I use plastic, phenolic and G-10, I use epoxy.
I agree. If you are not using glass/plastics, then wood glue works fine,
especially aliphatic resin glue.
As an example, I built my Loc Lil' Nuke using wood glue. It has flown dozens
of times on every H motor I have stuffed into it. It also recovers on a
streamer, rather than a chute. There are not any cracks or other damage to
the rocket.
--
Bill Nelson (bi...@peak.org)
Chuck Pierce
>I agree. If you are not using glass/plastics, then wood glue works fine,
>especially aliphatic resin glue.
>
exceptions?
I don't dispute that wood glue can be a strong adhesive if used
properly. I have two big complaints, though, against using wood glue
for more than small jobs:
1. Wood glue gets tacky REALLY quickly. I've dorked up several
airframes when the wood glue grabbbed the CR and/or tube couplers
before I could jockey them into the correct position.
2. Wood glue shrinks as it dries, so it makes some really crummy
fillets.
I haven't built any mass-sensitive models yet; so, since the added
weight of hte epoxy is not an issue, the slow-setting and nonshrinking
qualities of slow-curing epoxy make it my preference of adhesives.
Just my two cents, of course.
Mark Simpson
For larger rockets, I use triangular (I remembered this time, BK) balsa in
place of fillets. It looks good and strengthens very well.
Mark Simpson
NAR 71503 Level II
The Silent Observer
>
> >I agree. If you are not using glass/plastics, then wood glue works fine,
> >especially aliphatic resin glue.
> >
> Aren't all wood glues aliphatic by definition? If not, what are the
> exceptions?
Ordinary white glue certainly isn't aliphatic, and white glue has glued
a great deal of wood in the long years before Titebond and it's
relatives came out. I recall my dad making a scaffold board from a 2x4
frame and 1/4" plywood skins that weighed only about 20 lbs, but would
hold three grown men in the middle of the 12 foot span with only an inch
or so of flex. That scaffold board was glued together with Elmer's
white glue, and then tacked with 5d finish nails to hold it while the
glue cured (for several days).
In those days, white glue was a casein base, IIRC; that was before the
conversion to polyvinyl acetate as currently used. PVA is also not
aliphatic.
Carpenter's hot melt glue, aka rabbit skin glue, and real casein glue
have been used primarily for wood bonding for (in some cases)
centuries. None of them are aliphatic.
> 1. Wood glue gets tacky REALLY quickly. I've dorked up several
> airframes when the wood glue grabbbed the CR and/or tube couplers
> before I could jockey them into the correct position.
This is a genuine concern. FWIW, white glue is plenty strong for this
application, and tacks up somewhat slower than yellow carpenter's glue.
I usually (if I think of it in time) prefer to make these joints with
medium CA, which gives me plenty of time to move the joint around before
it goes off, is plenty strong, but sets much faster than even 5 minute
epoxy.
> 2. Wood glue shrinks as it dries, so it makes some really crummy
> fillets.
True, and it can also lead to dimpling in the airframe from internal
fillets, especially on centering rings. For external fillets, my
solution has been to make the functional fillet with the yellow or white
glue, put on thinly enough to avoid getting large bubbles that turn into
craters and applied in 2-3 layers. Over that, the
aerodynamic/appearance fillet is applied using Elmer's Finishing Wood
Filler for Light Wood, sanded to shape and then (optionally) hardened
with thin CA wicked into the surface; this gives a hard, strong fillet
that's as light as an epoxy mix with a large proportion of micro
balloons, and again much quicker to apply (given that it will never run,
I can do something else while the FWF dries).
> I haven't built any mass-sensitive models yet; so, since the added
> weight of hte epoxy is not an issue, the slow-setting and nonshrinking
> qualities of slow-curing epoxy make it my preference of adhesives.
> Just my two cents, of course.
Every model is mass sensitive -- just some more so than others. Still,
when you're using Estes class components and building to fly on Estes
class motors, the 50% difference in weight between a fillet made with
epoxy and one made with white/yellow glue and FWF is significant --
especially since that weight is at the rear of the rocket, and might
need to be offset by a similar amount of weight in the nose to restore
or preserve stability.
--
It is well to approach all wonders and miracles by gradual stages or
degrees . . .
Fritz Leiber
Donald Qualls, aka The Silent Observer NAR # 70141-SR Insured
Rocket Pages http://silent1.home.netcom.com/launches.htm
Telescope Pages http://silent1.home.netcom.com/astronomy.htm
Opinions expressed are my own -- take them for what they're worth
and don't expect them to be perfect.
Dave Lyle
> conversion to polyvinyl acetate as currently used. PVA is also not
> aliphatic.
????? Exactly what *is* an aliphatic glue?
http://www.taunton.com/fw/features/materials/2storglue.htm indicates
that PVA is aliphatic.
David Weinshenker
> ????? Exactly what *is* an aliphatic glue?
I _believe_ the term refers to the "yellow" wood glues
like "Franklin TiteBond" (in distinction from "white"
glue such as "Elmer's Glue-All").
-dave w
Doug Marrel
>Carpenter's hot melt glue, aka rabbit skin glue,
Ahem, source for this one ? Normal usage geographical area? I have to
try this one out at my next wood model ship meeting:)
Rick Dickinson
<cpierce....@knology.net> wrote (in his reply to Bill Nelson,
whose quotes went unattributed (Bad Chuck!):
>>I agree. If you are not using glass/plastics, then wood glue works fine,
>>especially aliphatic resin glue.
>>
>Aren't all wood glues aliphatic by definition? If not, what are the
>exceptions?
There are also polyurethane wood glues, like "Gorilla Glue". These
have the disadvantage that they *foam up* as they cure, and can push
parts out of position if not clamped securely.
- Rick "Glueru" Dickinson
--
Twice five syllables,
Plus seven, can't say much -- but...
That's haiku for you. D. Hofstadter
Mark Simpson
don't form rings, so, technically, any glue that doesn't have aromatic
groups is, therefore aliphatic.
See, I knew that chemistry degree would come in handy someday. ;-)
Mark Simpson
NAR 71503 Level II
The Silent Observer
A hundred years ago, or even 60-70 years ago, this was used everywhere
fine wood work was done, as well as everywhere artists worked in oil
paint on canvas. The most common current usages for rabbit skin glue
are in sizing artists' canvases, and attaching leather upholstery to
wood furniture frames. It's also sometimes used for glueing frames
without needing nails, brads, etc. to hold while the glue sets -- a
modest clamp time of about half an hour lets the glue cool to room
temperature, and it's then fully set, but it can be detached without
damaging the work by steaming the joint. In small joints, it sets fast
enough that you can simply hand hold the parts until the glue stiffens.
The stuff is kept hot in a pot over a small burner (Sterno, fondue lamp,
alcohol lamp, etc.), and allowed to cool when not in use. Takes a while
to come back up to temperature; figure on a half hour or more to get a
cold pot ready to use without scorching. If it thickens too much in the
pot, you can add some water.
You may be able to buy it in a powder form that you add to water and
then boil -- if so, it'd be most available at either art supply stores
or through catalogs that cater to specialty carpentry. If you get the
Klingspor catalog (aka The Sanding Catalog), you might check in there --
there are so many products I don't recall if I saw this.
There are also recipes in many older books on oil painting, as it's
positively the best stuff there is for sizing/sealing a canvas prior to
applying gesso. This is what allows art restorers to remove and replace
a deteriorated canvas from the back of a priceless painting; they pick
the canvas fibers out of the rabbit skin glue sizing, then use more of
the same stuff to glue on a new canvas, all while the paint is held in a
water soluble matrix from the front side. Many classical "old masters"
paintings have been transferred to new canvases this way, and thus
preserved for another few centuries.
For rocketry, you could use this stuff to attach fins, then apply heat
with a steam gun or heat gun to remove them if they become damaged; it's
a lot like using modern plastic hot melt glue, but easier to avoid using
too much and sets harder (set is about like white glue). Same thing
would likely apply in model ship building, though with very small parts
and joints there may be a challenge in getting the glue onto the part
and getting the joint made before the glue cools and hardens.
Leonard Fehskens
>????? Exactly what *is* an aliphatic glue?
Misspelled alphabetic glue?
len.