Using Elmers White Glue on Built Up Components

[Mike Griffin]

I know there has been some discussion in the past about using Elmers (White Glue) on structures such as built up flaps or tails and having a problem with warping since they are water based.  I use Elmers White Glue for 99% of my construction of my models and I wanted to show you how to apply it if you are doing a light built up structure such as a flap.

1.  DO NOT JUST POUR IT ON THE SURFACE.  I use a 2 ounce squeeze bottle with a 15 gauge needle (can order from McMaster Carr) and the secret is to just put little dots of the glue about 1/2" apart.  See Posted pictures.

2.  WEIGHT IT DOWN WITH SOMETHING HEAVY.  What you see in the pictures that I am using are 4" x 4" steel bridge shims that I bought from a steel fabricator.

If you will build the structures like this, you will eliminate your warping problems using White Glue.  Most folks use TOO MUCH and that causes the problem.

Hope This Helps

Mike

[Avaiojet]

Mike,

Nice work!

Thanks for taking the time to show and explain how you do your flaps.

I'll be making flaps shortly that are .25" thick. I was thinking of a built up structure like the one you have and it's similar to the flap structure in Robert's build Thread also.

How thick are your flaps? Will you taper them?

Looks like that's a profile model? How will you do your pushrod linkage? Control horn on each flap?

I just posted that question in a Thread.

Thanks again.

Charles

[Mike Griffin]

Mike,

Nice work!

Thanks for taking the time to show and explain how you do your flaps.

I'll be making flaps shortly that are .25" thick. I was thinking of a built up structure like the one you have and it's similar to the flap structure in Robert's build Thread also.

How thick are your flaps? Will you taper them?

Looks like that's a profile model? How will you do your pushrod linkage? Control horn on each flap?

I just posted that question in a Thread.

Thanks again.

Charles

Hi Charles

The superstructure of the flap is all 1/4" material and then I sheet them with 1/16th blasa on each side which will give me a 3/8" leading edge on the flap for this particular plane which is a Ted Fancher IMITATION.  Once the substructure is framed and dried and before I laminate the 1/16th to each side, I taper the flap my placing a 1/4" square piece of keystock on the leading edge and a piece of 1/8" keystock on the trailing edge, then take the perm grit bar and rough sand the taper on both sides of the flap.  I then smooth is out a little with a finder grade of sandpaper.  Once I have them tapered, I apply the glue and then the 1/16th laminate sheet and weight down well and let dry for a while.

As far a linkage on a profile, I usually apply a nylon control horn on the top of the flap with the holes in the horn directly over the hinge line.  I attach the short piece of carbon fiber push rod coming out of the wing which is attached to the bell crank with a threaded clevis locked on with a piece of fuel tubing and do the same from the flap control horn to the elevator control horn.  I had a Top Flite Tutor 2 ARF once that was set up like that and flew it for years with no modifications and never had a problem.  A lot of guys will use a wire flap horn with the horn welded to the wire and attach the pushrod with a ball swivel which is ok too.  

You will get definite and different ideas from folks on what they use and they all are fine if they are secure and do not fail.  I am not saying the way I do a profile linkage is the best but it is simple and works for me.

Mike

[Leester]

Mike, maybe I'm reading this wrong but when your tapering the trailing edge (to 1/8" ?) you want a 1/16" off each side at the trailing edge. Shouldn't you use 3/16" for the first side then flip over and then use 1/8" leaving the 1/8"  T.E. before sheeting.

[Avaiojet]

Mike,

Are you using CA to put the flap parts together before you do your sheeting?

I'll be cutting my flap parts today.

Thanks,

Charles

[Mike Griffin]

Mike,

Are you using CA to put the flap parts together before you do your sheeting?

I'll be cutting my flap parts today.

Thanks,

Charles

Charles I used Elmers to glue the parts of the flaps (substructure) together. There is no CA glue on the flaps at all.

Mike

[Mike Griffin]

Mike, maybe I'm reading this wrong but when your tapering the trailing edge (to 1/8" ?) you want a 1/16" off each side at the trailing edge. Shouldn't you use 3/16" for the first side then flip over and then use 1/8" leaving the 1/8"  T.E. before sheeting.

Lee you are right about the 3/16 but I did not have any so I had to improvise using the 1/8 piece that I had. 

Mike

[Gene O'Keefe]

Mike...glad to see you are up and moving around,  can't keep a good guy down for long.  I like Elmers too and it's easier to sand than epoxy when you have to.

[john e. holliday]

And one thing about Elmers that most people don't realize, is if you have an area that didn't stick well, an iron will make it stick.   I have done sheeting on leading edge ribs with Elmers put  on and let dry both surfaces.  Then iron the sheeting down.   Learned this reading an RC finishing article in Model Aviation years ago.

[Avaiojet]

Mike's flaps must be much larger than mine!

I drew my flaps out and even with just reasonable LE and TE, it would be pointless to build them as Mike has. There's hardly any open material near the fuselage and it gets solid half way up the flap.

I'll probably be better off going solid then make large round holes that change in size towards the tips.

The model is only 50" in span.

I was looking forward to making built up flaps. 

Charles

[Tim Wescott]

Actually, I think the secret is to weigh it down and hold it there until the glue has had a chance to dry.  I've done this, using much more glue, and had good success.

(I should think about using dots of glue though: everything I build seems to end up disappointingly heavy).

It's not clear from your post: using water-based glue for open structures is a no-problem thing: it's using it for lamination that may cause warping.  I've also heard reports that if you use it for lamination it'll never dry.  I haven't had a problem with this, but the folks I've heard it from are known to be fast builders, while there are generally weeks or months between me finishing a laminated piece and actually getting the time to prime it and paint it.

[Mike Griffin]

Hi Tim

I don't understand when you say "lamination" what you are exactly talking about.  Could you give me an example? 

Thanks

Mike

[Tim Wescott]

I don't understand when you say "lamination" what you are exactly talking about.  Could you give me an example? 

Sorry.  I was referring to what you're doing when you glue up surfaces onto a build-up structure, but I was probably misusing the word.  "Laminating" is probably more properly applied to things like making plywood or laying up fiberglass or carbon fiber.

Actually laminating plywood using water-based glues may cause some pretty severe warping.  I've done it quite successfully with balsa and Ambroid (and days of dry time), but that's different.

[Dick Pacini]

A simple lamination example would be the original Primary Force kit had a 1/2" fuselage made by gluing 1/4" sheets together.

[Mike Griffin]

Thanks for clarifying Tim.  Using Dick's example of laminating two 1/4" sheets to make a 1/2" fuselage, I prefer to use 30 minute epoxy for that application. I just brush it on and then scrape it with an old credit card to get most of it off and then weight down the piece with plenty of weight.  I have done laminations like that using Elmer's but I use the "dot" method and again weight it down and let it dry overnight. 

Mike

[Brett Buck]

I expect this is satisfactory in most cases, but Titebond is just as user-friendly and much stronger. Straight Elmer's may sand easier but that's because it's more brittle.

   Brett

[steven yampolsky]

I expect this is satisfactory in most cases, but Titebond is just as user-friendly and much stronger. Straight Elmer's may sand easier but that's because it's more brittle.

Aren't they the same?

[Tim Wescott]

Aren't they the same?

Nope.

Yellow "carpenter's" glue is definitely stronger than Elmer's, and I think there's a white woodworking glue that is, too.

And there's two yellow formulations with (I understand) different strengths, although all I've ever used is Sig-Bond.

[Douglas Ames]

And one thing about Elmers that most people don't realize, is if you have an area that didn't stick well, an iron will make it stick.   I have done sheeting on leading edge ribs with Elmers put  on and let dry both surfaces.  Then iron the sheeting down.   Learned this reading an RC finishing article in Model Aviation years ago.

Now that's a trick! I'll have to try it.

[Mike Griffin]

I have used Tite Bond but it does set up faster than Elmers white and in some cases to fast for adjustments I might have to make but it does work well too.  The only reason that I don't use CA type glues (except in rare occasions) it that I seem to be allergic to the fumes and it tears my skin up.  It is also like trying to sand rock after it cures.  I have also ruined several articles of clothing by dripping thin CA on them..

I buy Elmer's by the gallon and order the glue bottles and needles from Mc Master Carr.  They have the fastest service I have ever seen.

Mike

[Dick Pacini]

Mike, I find the use of glue dots to be an interesting thought, worth a try.  My concern would be edges that weren't sealed.  I suppose a compromise could be a very thin bead around the outline of the mating parts and then dots in the other areas.

[Mike Griffin]

Excellent point Dick and I have had that happen on occasion.  I usually just put a little of the Elmers in the voids and clamp till it dries.  The nice thing about using the Elmer's is that it dries enough in about 30 minutes to resume work on the part.  I must be getting more patient in my old age Dick because I don't get that much in a hurry anymore.  I figure the plane will be there in the morning if I dont finish that afternoon.

I was talking with Steve Buso a couple of days ago and we were talking about this very same thing.  I asked him how the Bobcat was flying and he said the last time he flew it, it flew great but it had been a while.  I then asked him if he was working on the HERCULES which is his new project and he said "Mike i go back in the shop and piddle.  I move something from here to there, rearrange a few things, look at my drawings and then leave".

I told him we must be related because I have gotten more and more like that the last few years.  Heck I go back in the shop, pick up an wing and notice a ding and sand it a little, put in on the bench, turn out the lights and go take a nap.  I think we have earned those naps...

I am going to do my best to fly out to VSC next year if my back will hold up and I have no intentions of flying.  I just want to pull up a chair in the shade and enjoy the fellowship and fun.  I already have a spot under Eric Rules tent.  I hope you all will not hold that against me 

Mike

[john e. holliday]

Hey you will never regret going to VSC.   A gentleman I could count on when I wanted to fly was ready to compete at VSC.   Him and his wife flew out to El Paso where his brother lived.  They came up to Tuscon for VSC and spent every day just sitting and watching the competition.   He stated that he had never had so much fun before and was looking forward to competing the next year.   But, his heart got to him about two months before VSC was to start.  I still miss him. 

Now for laminations like plywood on profile fuse sides, I have seen a couple that the white glue had not dried in the middle area of the lamination.  The edges were fine.   On a design like Mike Pratt's Primary Force with the 1/4 inch fuse sides I would and did use the Gorilla Glue.   Have to dampen the surface of one peice and apply the glue to the other peice.  Did not weigh it down.  Used all the clamps I had and sighting it to make sure it was staying straight.   Hung it on a hook to cure.   Next day I guess I used too much glue as the peice had growths all around it.   Even a hole that was in one side.   Sanded the glue off very easily and talk about stiff.   Still flying the plane as it is one of the best I have as far as flying. 

By the way Elmer's White Glue has its place and I use a lot of it.   Have even been converting over to the wood working glue they make.