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aubej
01-05-2003, 11:16 AM
Hey guys,
question for the guys who use wood glue exclusively. I know the strength of wood glue on let's say....pine on pine.....but what about balsa on ply?
Just curious. I've been thinking of using wood glue instead of epoxy on my new projects and was wondering how it works.....on a firewall for example?

Opinions?

Thanks,
Jason

KevinPerry
01-05-2003, 05:50 PM
I use wood glue and have had no trouble. The best part is that it doesn't smell :wink:

scholz
01-05-2003, 06:03 PM
Do you use wood glue instead of epoxy?

Do you still use ca?

scaleguy
01-05-2003, 06:16 PM
Jason,

By "wood glue" I take it you mean real carpenters glue? You know the yellow stuff from Lepagge!

rcav8tor
01-05-2003, 06:40 PM
Yellow Glue (carpenter's glue) or wood glue as you have called it is gr8 stuff. I use it almost for everything.... But no one glue is the end all. Many types of glue are available and should be used !!! :roll:

Yes. Cyanoacrylate (Glue Instant glue/Super glue/Krazy Glue) is used by most for everything..... and it is gr8 stuff. Remember how long we would wait for something to set up before we had this ?

Contact Cement is another glue I use all the time. (LePages Gell Contact Cement) I find is the best thing for laminating wood/wood or wood/to almost anything. Makes sheeting a wing or fuse a breaze.


As for your Fire wall and things like wing joints....... I'm sure most of the glues available would work for us........ Making sure everything is fuel proof.... But for me old habits are hard to break...... I use Two-part epoxy Cause I know it does it for me....

For most of your construction of a model.. (glue or what have you)personal choice is a big part of it.
I know guys that tell me my Contact Cement is too heavy..But I have prooved this wrong many times over...... for me anyway !!!

AJCoholic
01-05-2003, 08:31 PM
I have been woodworking all my life (grew up in the field with my father, three years industrial woodworking in college and 8 years full time work experience). I think I have a good handle on glueing wood, and regularly use in my shop white pva glue, yellow aliphatic, polyurethane glue, epoxy (laminating and structural resins) and also contact cements and even a few others!

I can only offer what my own experiences have shown me. I think your typical industrial (lepage for example) pva glue (white or yellow) is an excellent all purpose adhesive for ANY wood to wood joint, that being solid wood (pine,basswood,maple, balsa),plywood or other materials we may use such as cardboard. The only thing to watch is that the joint is close, as PVA'a offer little gap filling qualities and the joint strength is greatly reduced if the parts are not tightly fit. Also, some aliphatics claim to offer a good gap filling property but having a tight joint is still important. I would not hesitate to use this type of glue on ANY part of the airframe that will not become in contact with water and other liquids repeadidly. The only disadvantage is drying time.

When it comes to epoxy, I use it where I need a long working time, where I need a very good gap filling quality, and of course when dealing with very porous materials. Epoxies are good for gluing allmost anything other than plastics (some types OK, many not good). I use epoxy resins to seal large area such as fuel tank locations, firewalls and also to laminate large areas where I need (1) longer working time and (2) water based glues would cause the skins to swell and buckle - not good. The big disadvantage to epoxy is the weight penalty and of course cost.

CA - I think many people misunderstand CA glue, and say its not good for plywood, its not good for spruce, etc. I use CA for structural repairs on furniture on over 30 spevies of hardwoods and also it is my most widely used glue I use for airframe construction. I have NEVER had a CA glued firewall become loose, or had a problem with gluing ply to harrwoods, etc. Many advantages for us with time constraints, many disadvatnages also, but I live with them! I go through aout 48 to 60 ounces of CA a year in my shop. I love the stuff! Its amazing what strength the stuff actually has...

Contact cements are OK for close fitting,non porous larger surfaces and locations where the parts are not under stress. It has a lot of "creep" if under load and is not a permanent bond like other glues, since it never hardens but remains rubbery. Usefull stuff but I dont personally use it a lot in modelling.

I have not used the newer polyurathane glues a lotm but what I have used inmy business, they appear to be pretty good glues for most if not all wood joints. They are also good for many platics and foam. The biggest disadvantage is that since theya re moisture-curing glues (the catalyst to start the glue cure is water) theya re not good for dry wood, and you must mist the parts with water. I am not yet sure how much moisture to add, and have had a few of my joints fail due to insufficient moisture wher ethe glue did not kick over. Still getting the hang of these..

The best way to learn about glue is to test scrap pieces of wood and try and break them! You will find with most glues we use, if not all, the wood next to the joint will fail long before the glue joint.

Andrew Coholic

aubej
01-05-2003, 09:22 PM
Yup scaleguy, I meant the carpenter's glue.

Thanks for all the great info guys! That's what I love about asking a question here...lots of experience to draw from. :D

Jason

Derrick
01-05-2003, 10:03 PM
I just finally tried some Titebond II glue. I am not sure if I really liked it or not. I am too impatient when it comes to waiting and really have gotten used to the quickness of CA.....
Some guys swear by Titebond and some even use it on their firewalls. I would still rather good Ol' Epoxy on the firewall......

Andrew:
What's your thinking on Titebond?

rcpilotsteve
01-05-2003, 10:25 PM
Aren't most wood glues water based? Wouldn't that cause warps in the wood? Other than alphatic resin.
****************************************
I use very little CA mostly Sig's Alphatic Resins and 2 part epoxy for most of my projects but, 90 % of my experience is red and blue loctite! :oops:
I build Heli's :!:

Bob Hudson
01-06-2003, 06:32 AM
Hello Andrew

Great "Glue Review", thanks.

Interesting to hear you use as much CA as you do for your "industrial" applications.

Can you tell use what brands you use, and /or, different formulas (thick, thin, flex, etc).

Thanks, Bob

AJCoholic
01-06-2003, 06:35 AM
Titebond is an aliphatic, water based "yellow" carpenters glue. I am sure it is just as good as any other brand, but again, try a test! Glue up a firewall (mock) and try and break it. You sometimes get a real surprise how strong the joints are.

The only place I can see a problem using water based adhesive on wood is when you have a thin large area (like wing sheeting) that may buckle and twist when the glue is applied making it harder to get flat. On regular joints where the glue is applied only to the joint itself on sticks, edges, etc cant see any problems.

I have also used Elmers carpenters glue, the water resistant kind, and find it a good one. But we use 90% lepage industrial white pva in our shop, by the 5 gallon pail. Its amazingly strong glueing wood to wood.

Andrew

AJCoholic
01-06-2003, 11:34 AM
Bob,
I use Flash thin and medium only, as I buy it from Great hobbies in 2 oz bottles. I use it fast enough that it never clogs up and I never throw any out.

I have tried Balsa USA CA, Zap, Flash, Sig CA, Hot stuff (which I used for years), Goldberg jet, and some industrial non-hobby brands (from an adhesive supplier) and find that ALL of the stuff is pretty much the same! I never found that one was better or worse, but the bottles do make a difference, I hate the Zap bottles for instance.

In my shop, I use CA to repair blow-outs from machining operations regularly. For instance, when I am running moldings on the shaper/moulder I can glue a chunk back and immediately re machine. Its a time saving thing, and since CA is basically inert after curing, it doesnt react with our finishes.

Andrew

JimMcIntyre
01-06-2003, 12:10 PM
I use.
- Yellow "Carpenter's glue" for most framing
- Epoxy for firewall and "glassing" centre section of wing etc.
- Silver solder or JB Weld for metalbonding

I love the Caprenter's glue. A nice, light, sandable, flexible bond that cleans up easily (wet rag) and gives you time to get the alignment right. No health concerns and it's cheap.

I don;t mind the cure time. I just clamp/jig and move on. Sometimes I have several building boards going at once so no need to wait for cure time.

Bob Hudson
01-06-2003, 12:20 PM
Andrew,

You might want to consider trying Cyberbond CA.

It 's available in bigger bottles.

Contact Steve Evans the IMAC secretary, he is a Cyberbond disti.

Steve Evans
E-mail Address(es):
SEvans@centurytel.net

Bob

KevinPerry
01-06-2003, 03:31 PM
I like that paste they gave you when you where in first grade . When you got tired of gluing things you could eat it :!: hehe just kidden :wink: