zvez

So have cynoacrylates pretty much taken over model construction now? As noted in another post I've been away from flying for maybe 40 years! (wow that long!). Back when I learned (and absolutely loved building as much as flying). TItebond water-based glue was standard for construction, with epoxy being used for certain components. Then in the mid-70s, "hot stuff" came along, I think it was the first cynoacrylate used in rc construction. It greatly sped up the construction process.

Could someone give me a brief synopsis of adhesives used today in construction of balsa models? I did a search but couldn't really find anything specific, if you have a link that'd be fine too.

Thanks!
Chris

sensei

It is still pretty much the same rules, today I use nothing but CA on all balsa and plywood structures.

Bob

Charlie P.

I use CA for the wings but otherwise I am stuck in the 1970's for fuselage work and laminating. I like SLOW epoxy (West System - "4 Hour") and Titebond PVC glue.

I'm about to fiberglass sheath a pair of 44" foam floats and it will be 1970's technology all the way.

I like CA, but it isn't manditory.

jester_s1

A lot of the kits now are designed to be built with CA, especially the wings. You lay up the whole interlocking structure and get it straight, then hit every joint with a drop of thin CA.

bigtim

My Feedback: (13)

the nice thing about CA is the instant bonding you get when the joints are tight speeds up the building time for sure.

in many cases I like to use Tite Bond because of the lack of odor and that it sands easier, one of my club members who happens to be a great builder thins his TB down just a bit with water and applies the glue with a acid brush to the contact points its about comfort and situations,when gluing sheeting together I always use Tite Bond for that reason of being sandable CA just turns the wood to stone.

CA is great I like to use a applicator tip when using thin CA for adhesive control its nice to just set up some ribs and hit them quickly and your wing or fuse framing is done in no time,I also use allot of Med.thickness as well for higher required strength areas.

zvez

Thanks guys for the insights!

Hossfly

Insight or outsight, your choice! I am pretty much like Charlie P. In reality my choices are whatever I think will work O.K. for the specific job at the time of application.

The white glues are great for wood when the joint can set for a significant time. Otherwise I may use 5 minute epoxy or 20 minute epoxy. Any portion of a firewall gets the 20 minute treatment, along with significant bracing usually more than needed. Another treatment of firewalls is that ARFs need better. Around the firewall, spreading Epoxy by using a heat gun allows the epoxy to water itself into all cracks and crevices. ARFs, IMO, all ARFs need a restructure of firewalls.
Two incidents reinforce my thinking there. 1 is that a number of ARFs have had an engine and firewall depart the airplane in flight. Not good!
2. Had a local club member attach a G-23 to an air-frame that was designated .45-.75. He made a bad landing, then shortly after proceeded to start up again. He was tacking the engine IN FRONT. Engine wished to fly!!! And so it did, taking right hand thumb and forefinger with it. Club Member got him to hospital quickly.
I inspected that firewall and I would not have placed a .45 on it without a complete rebuild first. No matter the glue that ARF was an accident waiting to happen. It was actually glued with CA. Typical ARF!
Another funny was in a magazine - now gone defunct - "review" on a twin engine ARF model with electric motors. The review was so super about the model. (Aren't all reviews like that?) However they did mention that on the 3rd flight, both motors DEPARTED the airplane.

So I do not have any worries about some extra ounces or what everyone else does. I build it to stay! On my big birds I also include a couple of 90 degree metal parts bolted to firewall and fuse. sides, which have not less than a side of 3/32 hard plywood. Epoxy of at least 15 min. stuff.

HighPlains

My Feedback: (1)

I still use model airplane cement for anything that I plan on sanding, since it sands better than any other glue. Internally, it's a combination of epoxy, Gorilla, Titebond, and Ca glues, depending on the materials I am joining.

049flyer

My Feedback: (18)

CA is great for repairs, gluing back together all of those little pieces.

But it doesn't get much use on my building bench. I find it that it's disadvantages far out weigh it's ONE advantage, which is speed. I much prefer Sig Bond or TiteBond for general construction with good old Ambroid or Sigment a close second. For high stress joints I use 30 minute epoxy and sometimes 5 minute epoxy for not as high joints usually laminations.

I also find finishing epoxy very useful and have been using it more and more lately.

My CA always goes bad before I ever finish a bottle!

zvez

Something we started doing after hot stuff came out (first CA used in RC). We'd use titebond or even longer cure epoxy for the main gluing but use dabs of CA to hold the pieces together in place of clamping and such.

sensei

I have to be honest, I read horror stories about the use of CA on our models but I have never witnessed any of them for myself, I have also seen the inside of many ARFs with allot of what looks and feels like hot glue on the joints, but maybe it's CA. What I know for sure is I have personally never flung an engine off the front of one of my airplanes because I used CA, and that is all I use. I fly my stuff as hard as the next guy and I do it with 50cc through 200cc. Just saying...

Bob

049flyer

My Feedback: (18)

Just like some are able to cover with Monokote or UltraCote and get perfect finishes that never loosen, pull up, wrinkle, shrink or fade, some are able to get great results with CA. Unfortunately I am unable to get satisfactory results with any of them. Perhaps I haven't figured out how to properly apply and use the products, perhaps my standards are too high. Who knows?

My experience with CA has been that it is irritating to my eyes and nose, expensive, brittle, prone to weakness unless the joints are perfect, and hard to sand. But the biggest disadvantage is also it's biggest advantage. It is incredibly fast, sometimes too fast. It's very easy to screw up by gluing something together that is not aligned or placed just right. Very hard to make small adjustments as the glue sets.

I enjoy building and am rarely in a hurry to finish anything. I have several different projects ongoing at anytime and am more than willing to set something aside while the glue dries and turn my building attention to another assembly or airplane. So a slower glue is not a problem for me.

I expect my planes to last for years, so I focus on methods and products that are reliable, work well and will last.

manks7477

I use a lot of standard wood glue for most construction, then pin it together to let it cure. I still use CA in spots, but hate the smell and getting in on my hands. 60 / 30 / 5 min epoxy for higher stress joints, ini some spots I will mix in Micro-Baloons with the epoxy.

I am no expert, but have put together some 12 kits, the last was a TF Gold Edition DC 3 the next is a TF Gold Eidtion Corsair that I will build together with my 13 year old son.

TPL33

Also important with CA.....saves weight.

chuckk2

There are too many adhesives out there to begin to think about the relative advantages, etc.
The "right adhesive" is stronger than the parts it glues together.
Where flex is needed use a flexible adhesive.
Besides the Various CA glues.
Some of the canopy glues (Uhu Pro, etc) can be used if a moderate strength flex joint is needed.
I also found a craft glue "E-6000" that works well, but eventually gets rather hard.
I prefer 30 minute to an hour Epoxy. The shorter time versions don't usually have the strength,
and rush the mix and settling time.

cordell staker

just for nostalgia I always use Ambroid glue on something in every kit or ARF. The smell of Ambroid brings back my childhood modeling memories.

Lifer

My Feedback: (1)

Ambroid gets you a little high, too.

(At least that's what I have heard.)

HighPlains

My Feedback: (1)

I've almost always bleed a little on just about every model I have built. Didn't matter much as to type of model, it happen when I was 8 or 9 putting rubber models together using razor blades, or glass and foam models years later. It never made them any stronger, but I left a red spot on quite a number of planes. The best use for Ca is to seal the wound.

sensei

Unfortunately I am unable to get satisfactory results with any of them. In the words of Jeff Foxworthy: Well there you go...

I expect my planes to last for years, so I focus on methods and products that are reliable, work well and will last. So do I, and mine actually do last for years while being pushed to the limit just about every flight. Just because one uses an adhesive like CA, it does not mean that it is not a reliable bond line or that their airplane will not last for years. It comes down to things the builder should be doing like insuring the fit of joints near perfect prior to bonding, the use of balsa tri stock needed in key areas and a few other tid bits along the build.

I did not state that everyone should be using CA, I only stated that I read horror stories about the stuff, but have never witnessed it for myself. I believe everyone should use what they like working with and leave it at that, kinda like the covering you spoke of, I get great results with the plastic coverings, but I also get great results with glass and paint, or cloth covering and paint, but maybe I am just lucky. Who knows?

Bob

Tarasdad

I've used CA, Titebond II and Gorilla wood glue for building. My latest build (CG Super Chipmunk) was built almost entirely with wood glue. Cheaper, no irritating odor, much easier to clean up after. Plus, a well fitted joint glued with wood glue is far stronger than the wood.

zvez

This has been a great thread to read, interesting to see the different techniques people use and that all seem to be successful.

What I'd really like to do, it get an arf to familiar myself with flying again (it's been since 75 or thereabouts!) But get a big kit to build, I love the Balsa USA kits the various planes they have and have been fascinating by the gentlemans build thread on the nieuport 28!. So I'd like to get that and just take my time and build it for the fun of it and who knows someday get back good enough to fly it!

I just always really enjoyed the building aspect most of all.
Back in the day, they always used to say some of the competitors in scale model competitions were some of the most marginal pilots as most time was spent building the magnificent specimens they did!

rmh

For over 20 years, in the business of designing/building custom building competition models -and have built hundreds of models mostly gasoline or glow engine types - now, electric powered .models , many of em factory assembled are setting around in my shop. I started with a Time Flies , all planked class A, scale, control line kit-

We all remember the horrid rubber kits with knotty sheets of terrible grain balsa sheets which required you to cut bulkheads from them - good luck on that.
The latest ARFS from China are marvels of engineering.
The "framework is made from fine laminates of wood unusable in any other form - then machine cut by computer to utilize all but a bit of dust. the good designs mechanically interlock most of the framework and the adhesives now are very good.
earlier attempts were dreadful but currently these models are done in a fashion I could never have duplicated -unless I had the computer run production tools.
An old friend built award winning RC scale stuff which was heart stopping to fly (heavy as sin) !
If you want a task- try building an aerobatic model which weighs under two ounces -
without present materials - forget it.
But we still enjoy assembling small balsa models -----------

Bozarth

My Feedback: (15)

My sinuses react to CA fumes so badly that I can hardly breath through my nose for several days. Never believed it until it started happening to me. I used to use Hot Stuff by the gallons.

Kurt

HighPlains

My Feedback: (1)

A lot of long time builders report Ca reactions. In the home built airplanes area, some builder that use a lot of epoxy also report skin reactions after long time exposure to epoxies. I have never heard of a problem with traditional model airplane cement, or any of the white glues.

Oh, but nobody builds that much these days. Just a problem for curmudgeons.

zvez

I can see the temptation in not building, I'm just floored at the quality of the arfs I've seen. They were always ugly ducklings that everyone laughed at back in the day. Now, well completely different.