Too much glue applied
 

While attempting to glue the bottom leading edge sheeting to a wing with thin ca, I applied a bit too much and enough of it soaked up into the sheeting to the point where I cannot bend the sheeting over to be able to attach it to the ribs at least for the first 1/2 " or so. Now I'm considering one of two options: cutting the sheeting from the leading edge, sanding the residue away and re-gluing a new sheet or...with the use of Acetone apply it to where the excess is, allowing the Acetone to soften the ca and then bending it over the ribs. Does this sound like it might work?

I would cut and replace.
You may like the speed of ca but have you used titebond before?
It gives you plenty of time to get things positioned just right.

Jolly,
I agree with 3136,when gluing a wing ,you really want to glue it in a free state.If you force the sheeting,or force a spar into a rib,you will get spring back,hence twist in your wing.When I sheet a wing,I spray the sheeting with glass cleaner with amonia,pin it down and let it dry.Then go back and glue it with titebond.I'm old school,everyone has there own method,it depends what result you want.
P.S.-Always wipe off excess glue,it just makes more sanding.-jeffo

I agree .. replace it and I also would glue it with Titebond 11 . A light spray with windex to help with the bend .. some magazines to hold it in place .. CA is too hard to sand.. Its great for the cap strips though . For the cap strips you cut your cap strip to length . Run a bead of med ca along the rib .. Lightly spray your cap strip with accelerator and put it in place . Bang its home ..

I find it hard to wipe off the excess glue when you put the second wing skin on so I find it easier to use a syringe to place my glue . That way I don't use too much glue . I do wipe off excess where ever I can because it is just weight that you don't need ..

yeah I see where I made my mistake. This problem occurred when gluing the front edge of the sheeting to the bottom leading edge. Cutting the sheeting away sounds like a good idea but then I would have to remove what's left behind as well as the ca residue. Lots of sanding using acetone to soften the old ca.
I guess I'm going to try softening the wood where the excess ca seeped up into with acetone and try to bend it over the ribs with the help of a little glass cleaner and ammonia. If that doesn't work then removal of the offending sheeting will commence there after.
It's just that I'm afraid of doing to much damage to the leading edge while cutting the sheeting away.

Jolly Roger, soak the infected area with acetone. The acetone will dissolve the CA glue. It will not affect the wood. You may need apply some new glue to all the areas that you removed glue.

jollyroger,

This posting will not make me popular by some but will protect your skin and your lungs so it is worth the risk of some negative comments.

My outlook is _ _ _ remove the sheeting purely by mechanical means; a hand plane and abrasive material like sandpaper.

I wonder if the recommendations of softening the CA with solvent (like acetone) is from these fellows personal experience or just repeats.

The quick evaporation of the solvent will affect your lungs more than the glued wood. No face mask will protect you unless they provide your breathing with a cylinder of compressed air and no environment air.

Your choice _ _ _

Zor

I have used acetone on the job every day, for the past 40 years. I don't know of anyone to have a problem with it in my trade, of Tool & Die and machinist, and I know alot of them. There maybe someone, but I never heard of them. Plus I use it at home, and so does the wife to remove nail polish.

Pat

There are many more chemicals that we use in this hobby that a LOT worse than acetone. Most women use acetone to remove finger nail polish, I don't see them dropping over dead!

Frank

Gotta agree with everyone who recommends Titebond (I use Titebond II myself)... takes a while longer to set up, but also allows you to reposition AND keeps you from rushing.

Hi Pat,

As I predicted I would read negative comments.
I do not read the type of usage nor the possible amount used.
Women use just a few drops to remove their nail colors.
That nail color is like dope not like CA stuff.

I have experimented in softening CA with acetone. I had to keep it acetone-wet for many minutes which meant to keep applying the acetone as it evaporated fast. This fellow has a whole length of leading edge to unglue if I understood well his predicament. I do not know what method he was thinking of using to apply the acetone. I can only figure that a whole length of 12" to possibly 30" or more. That would mean many square inches to keep wet until possible separation.

I glued a small piece of 1/16" thick balsa on a piece of scrap leading edge using thin CA. It does not matter in what format it is glued on but there is an area of glue to be softened and get separation of the pieces. I first applied acetone to the section not glued to see how long it would take to have he acetone go right through the 1/16" thickness. It took less than a minute and I had my finger all wet passing it underneath.

I then applied the acetone to the glued area using the eye dropper and keeping it soaken wet for 15 (fifteen) minutes.
There was no way of separating the pieces. I then could only think of 12" or much more of glued leading edge sheeting.

I am satisfied with my experiment.

Zor

Edit to explain the last (right) picture. It was an attempt to show that the whole surfaces were all wet with acetone for 15 minutes. I must have used 3 or 5 table spoons of acetone to keep it soaken for that 15 minutes.


http://www.rcuniverse.com/forum/atta...mentid=1940475http://www.rcuniverse.com/forum/atta...mentid=1940476http://www.rcuniverse.com/forum/atta...mentid=1940477http://www.rcuniverse.com/forum/atta...mentid=1940478

I also have been using acetone for nearly 40 years with no ill effects to my well being, now I do generally use it in a well ventilated environment though... If you want to keep acetone from evaporating so fast then soak the infected balsa area along with a paper towel on top and wrap in Handy-Wrap, it will keep the acetone from evaporating so fast and working for you much longer.

Bob

Hello Bob

If you do not mind me asking _ _ _
How often do you use acetone and what do you do with it ?

The wrapping sounds like a good idea.
How much time does it take to soften the CA enough for the parts to come off ?
In my experiment it did not after 15 minutes.

Zor

Third option: CA debonder?:

http://www.zapglue.com/ca-debonder/

Other brands are available.

I haven't seen this option mentioned, and I have no experience with it, Just throwing it out there.

Here is some text I found

Most of the solvents used for removal of cyanoacrylates adhesives are either highly flammable or toxic and should be used with great care. Components should be checked for compatibility with the solvents. They may require soaking for a number of hours to remove the adhesive. Listed are some of the solvents: acetone, acetonitrile, methylene chloride, methyl sulphoxide, and dimethylformamide.

I still feel that mechanical removal is the safest and fastest method to separate parts glued with CA adhesive as I recommended in post #8 and the idea also mentioned in the previous post. .

Zor

P.S.: by editing.
This thread was about removing CA glued sheeting from a leading edge.
While I mentioned the risks of using acetone it was not intended to turn the topic into posts intended to disagree with the risks.
End

I am now and have have been in the aerospace composites business all of my adult life, so I have and do use acetone more then most ever will. As for the length of time it takes to de-bond, I have never timed it because it just doesn't matter to me...

Bob

Lets get back to the subject at hand. I have used the CA debonder Bob Smith makes and it does take time to soften the CA and you have to work at it to get the pieces apart. I prefer to but join sheeting with Titebond but may use either Titebond or CA to apply it to the wing depending on application.

I would slice the sheeting across the grain between ribs and then use acetone one rib at a time. For the person who asked if this is something I've heard or something I've done, I use acetone all the time to remove CA. The sooner you use it the faster it works.

Now depending on how long it took in this situation I might instead cut away as much sheeting as I could leaving only a slice over each rib. I'd use a very sharp razor knife held parallel to the surface of the wing and cut from leading edge to rear of the sheeting to slice of "layers" so there was very little left to sand.

MEK works as well as acetone but evaporates much slower. It's also considered a carcinogen. Because I'm immortal I don't have to worry about things like that but other might need to.

i have seen some drop-dead-beautiful women and none of the smelled of acetone. i hauled zillions of gallons of it with my big truck and it never hurt me.

Like I posted, I've never used debonder because I rarely use CA. My LHS carries CA debonder and I've been curious as to its effectiveness. When you write, "work at it", do you mean several applications? What is the condition of the wood after the process? Are you stuck reusing CA, or can you switch to an aliphatic resin like Titebond?

O.k I 'll throw my dog into this fight.:D CA debonder is nothing more than acetone or some similar solvent sold at an outrageous price. Buy a can of acetone and soak the crap out of it outdoors and wait forever to have it come loose or chop it away and sand off the rest. Pay your money and take your choice. Learned this lesson along time ago, there's a time and a place for every glue. I use thick CA only at the leading edge and then wood glue from there out with weights to hold it down. In an hour the wood glue will set up enough to hold and you can move on from there. Jump on RCU while you wait and learn something new; or not.:rolleyes:

You need to give it a little time to work and then slowly work at breaking the joint. I haven't tried switching glue types after debonding so I can't comment. I have tried the Super Phalic! shown below from Horizon Hobbies (had the LHS order it). Its a special formula yellow glue with an applicator that goes on like CA and dries fairly quickly. I have started to use it more and more of it but have switched over completely. I purchased some of their Eze-Kote Finishing Resin (again a yellow glue project) to fiberglass my current project. I thought it might have an easier clean up than epoxy and I can't handle fiberglass resin fumes due to a lung problem.
[h=3]Super 'Phatic! [/h] By: DELUXE MATERIALS
Item: DLMAD21

[h=3]Eze-Kote Finishing Resin, 500 ml[/h] By: DELUXE MATERIALS
Item: DLMBD37

I bought debonder when I first realized it existed and before I knew that acetone worked. It wasn't straight acetone. In fact, I think it was nitromethane. I didn't recognize the smell.

It didn't work very well and nothing close to as well as acetone. I wouldn't buy it again because as stated it's over-priced and my experience with it wasn't that great.

Acetone is the safest bet, but MEK is better when you have to cut through a lot of CA because of it's slower evaporation time.

Crossing debonder off the list. Thanks for sharing your experience.