Dumb questions: Testors and CA glues~How do they dry?

[clovis]

I'm back to the hobby after a 25+ year hiatus. I am using super glue on my second model ever.

I bought a few two packs of super glue at the dollar store. Overall, this glue is working well. I am so used to the old school Testors glue that I have a small learning curve.

One bit of that learning curve is that I caught myself starting to glue up pieces before I retired for the night, just so they could dry overnight, LOL, even though I was using super glue.

I read once that the old school Testors glue bonded plastic thru a chemical reaction, and until that chemical reaction took place completely, no amount of air, hair dryers, etc. would make them dry any faster.

Is that true?

Do super glues, when used on plastic, work the same way?

[slusher]

what I like about Testors orange tube glue is that if you don't use to much you can get parts apart easier. I use Loctite super glue on hard to hold parts it dries in like 15 seconds so I would think the air would help it dry. I use both glues..

[mnwildpunk]

I do know testors tanex and mek all work by basically melting the plastic to sort of weld the parts together super glue and epoxies I believe work in a different way I should have researched more before I answered sorry

[unclescott58]

I use super glues and sometimes Testor's old glue in the tube. But, what I use most of the time is Testor's Model Master Liquid Cement for Plastic Models. It gives me a good bond, good control, very little mess, and is easy to handle. I maybe switched to this as my primary adhesive about 20 years ago, with great results. For clear parts, I use Testor's Model Master Clear Parts Cement & Window Maker. The only thing I really stay away from, and I'm not sure if they even make it any more, is non-toxic model glues. Never had any luck with the bonding results with those in the past.

Scott

[Ridge Rider]

For small parts and thin joints I prefer Tamiya extra thin--also similar are Tenex and Ambroid. They weld the joint and dry fast, workable in minutes unless it's very fiddly parts. The thicker tube type work well for big surface areas like wide flat plastic areas but do take longer to dry. The super glues are contact surface only and have different curing times so I would research for your needs. Personally I don't like the super fast so I can adjust the fitment as well as not accidentally glue my fingers together. This has been discussed before and a forum search should give you some more answers.

[randx0]

I think using the liquid glue (not just Testors) is the best all around glue . super glue has it's place but keep it away from clear and plated plastics , it can react and ruin the finish . the old orange tube glue has it's uses also . trial and error will be the best teachers . other glues to try elmers white glue for attaching windows , five minute epoxy for those places that super glue shouldn't go , rubber cement for mock up purposes clear gloss paint for attaching photo etch scripts. theres a million adhesives and a million ways to use them .

[Art Anderson]

The ordinary range of plastic cements, from pure liquids, to liquids containing a bit of cellulose, to the thicker, syrupy tube glue (such as Testors in the orange tubes) all are based on so-called "hot" solvents which actually dissolve the mating surfaces of polystyrene plastic (the plastic most commonly used in molding plastic model kits), which causes the two pieces to blend slightly together at the joint. They dry (or "cure" solely by evaporation.

CA (short for cyanoacrylate) glues, commonly called "Super Glue" doesn't rely on evaporation to do its job, but rather it's a family of adhesive that goes from liquid to crystalline quite rapidly, triggered by a number of causes, most commonly pressure between the two parts being glued, moisture, temperature, along with the introduction of finely divided powders such as talcum powder or baking soda. CA glues come in a range of viscosities, from the extremely thin liquid grades found in the checkout lanes at "big box" retailers, to medium to thick viscosities found in hobby/craft shops and some hardware/home improvement stores, to even gel consistencies, and most recently even "flexible CA glue" designed for use with fabrics.

There is a widely held notion out there that CA glues simply cannot, and should not be used for the assembly of clear or plated parts on a model kit. However, I've been using a commonly available medium viscosity CA glue for a good 25 years for a great deal of model car assembly, and use that almost exclusively for attaching clear parts (windshields, back windows, side and vent windows) into finished body shells, as well as ALL "chrome" parts. What is needed there, to prevent the "out-gassing" which leaves that smokey, cloudy film around the glue joint, is a liquid chemical "accelerator" which kicks a medium (almost always much slower setting) CA glue from liquid to solid in literally seconds. What is vitally important with accelerators is that they not attack painted, plated or raw styrene surfaces, which many will do. However, I found, back in the late 1980's, a brand of CA accelerator that not only does not attack painted or raw styrene surfaces, but itself is a slower evaporating, non-solvent liquid, which when sprayed on the CA glue joint, literally wets the surrounding surfaces, which prevents the vapors of the CA from creating that foggy appearance.

I use just one brand of CA glue for almost all clear and plated part assembly: Goldberg SuperJet, which is available in many R/C oriented hobby shops as well a directly from Tower Hobbies. In addition, a company, Bob Smith Industries, has produced since the late 90's the brand of CA Accelerator I use: "Insta-Set", which comes in small transparent spray bottles (they package it in several sizes, along with offering 8-oz refill bottles as well). This accelerator is a blend of synthetic hydrocarbons and aromatic amine. Bob Smith Industries (BSI) also makes a range of applicator "nozzles" that slip-fit directly onto Goldberg Jet and SuperJet bottles, my favorite of which is their "BSI-345", a polyethylene (soft plastic) long needle tip (capillary tubing) which is perfect for applying CA's in tight areas, as well as tiny drops where needed. Again, a lot of hobby shops carry these, which are also readily available from Tower Hobbies.

Art

[Harry P.]

I read once that the old school Testors glue bonded plastic thru a chemical reaction, and until that chemical reaction took place completely, no amount of air, hair dryers, etc. would make them dry any faster.

Is that true?

Do super glues, when used on plastic, work the same way?

Testors tube glue has solvents in it that literally soften ("melt") styrene plastic, so the joined parts get sort of "smushed" together along the mating surface. The joint dries via evaporation of the solvents, and can take some time to fully dry.

Super glue doesn't soften or melt the plastic parts at all, it holds them together the same way epoxy does, by literally "grabbing" onto the parts–the glued joint relying on the strength of the cured glue itself (and how tightly it can hold onto the plastic parts). CA is an acrylic resin (CA stands for "cyanoacrylate") that doesn't "dry" (as in evaporation), but "cures" or "sets" via chemical reaction to water vapor (the humidity in the air).

[scalenut]

technically none of there are "glues" , they are adhesives( or cements).

Edited July 10, 2014 by scalenut

[Harry P.]

technically none of there are "glues" , they are adhesives( or cements).

glue [gloo]

noun

1.

a hard, impure, protein gelatin, obtained by boiling skins, hoofs, and other animal substances in water,

that when melted or diluted is a strong adhesive.

2.

any of various solutions or preparations of this substance, used as an adhesive.

3.

any of various other solutions or preparations that can be used as adhesives.

[scalenut]

.........made you look.

[clovis]

Thank you for all of the replies!!!!!

I glued this latest build up using CA on 90%+ of the model.

[jbwelda]

superglue was originally developed to be used for field sutures in battleground situations. that's why (well not really *why*) it bonds skin to whatever, but especially other skin, so well.

jb