rt4957

On the build I`m doing (Sig Wonder) the last few things I have done to the plane have resulted in Brittle easy to pop off Joints.

I have been building this exclusively with Wood Glue (Somehow going with CA just didn`t excite me,,I wanted a stong model with time taken),but the Former that holds the wing dowels to the Fuselage (F2) and also the Top from the wing to the firewall just seemingly came loose with little force after a night of setting.

I was using the same bottle for the whole build,,still have about 1/4 left,and am curious as to if it got contaminated,,maybe by leaving the cap off overnight?But it`s not humid or "Wet" here where I live.

Just Curious
Rt4957

TedMo

You do not say what glue you are using. However,I've been using wood glue of various types all my life (85 yrs .) and never had that problem.Sure doesn't sound good. For me CA is the wonder glue, love it.

jester_s1

Wood glue doesn't make your joints any stronger, at least not on the stuff we use it for. It just gives you some working time to make sure the fit is right. With either adhesive, the glue joint is stronger than the surrounding wood if it's put together right.

Gray Beard

My Feedback: (-1)

When wood glue goes bad it is the water that evaporates and leaves a thick paste behind, very easy to notice and no mistaking when it's time to toss. I have had one opened bottle of the GP wood glue for 5 or 6 years and it's still good. Not all wood glues are the same and some brands do hold better then others. At my wood working club we are now only using the titebond #2 and 3. It's used for everything from chopping blocks to furniture with good holding power.

rt4957

I hadn`t wanted to go brand bashing,,I have been and will continue to use Sig bond.

The joints coming loose was probably a good thing anyway as they were on 2 areas that if failed in flight (Whenever and if ever that day comes) that there would have been a major catastrophic failure of the wing hold down.The cabin top may have been under pressure from the tightly installed Fuel Tank,,the lines might have been pressing the top.

I have since epoxied the thing across the fuselage and Used CA on the cabin top.
Probably my own mistake,,but the glue seemed very brittle and the pieces came off easy

I was under the asumption that wood glue/aplpha resinic would give a better hold as you could actually see the joint with the color.

That plus I want to enjoy the build,,not do an overnight deal since the Wonder goes together so quickly anyway.

Thanks for the replys and the knowlege
Rt4957

carrellh

'Something' happened to the glue you have. I would just toss the existing bottle and pick up a new one.
I've never used the Sig branded glue but I would guess they buy it from a glue factory and put it in their own packaging, and that is probably true for many brands.

I like using wood glue for the extra working time it provides. I keep wood glue and CA on hand and use the one that seems to fit the application.

huck1199

I label my bottles when purchased. I have apint of Elmer's Carpenters glue from 1998 that is still usable. I mixed a little water in last year.

ocelot31454

When you say wood glue, exactly what type are you asking about? White glue and wood workers glue do have a shelf life of about 3-5 years IF kept warm. If alowed to freeze that life drops to about a year and a half. If either glue is frozen and thawed more than twice, get a new bottle.
Hope this helps.

ron ward

ocelotS got it about right....
any of the alphatic resin glues will last for years and about the only way they go bad is by drying up or freezing. it sounds very much like you got a bottle that had frozen earlier, before it was put on the shelves where you bought it. when it freezes,the yellow accellerator(alphatic resin)seperates from the pva because it (the resin) won't freezeandthe glue dries brittle andweak with reduced flexibility. i'd bet your's did because as you described the "brittle" easily broken joints, that's exactly what frozen " yellowglue acts like". does the dried joints look alot lighter in color ,almost white? ionce worked at a shop where the glue was purchased in 35 gallon drums as plain white elmer's and we added our ownaccellerator to get thesetting speedwe wanted.... lot's forlaminating and edge glueing, very little for doors, so wehad more time to get the parts lined up.
i can't count the times i've come out to my shop to see that i left the cap off of my catsup bottle again, sometimes for daysand inever once had any type of problem from the glue drying up. i go through about a gallon a month in the warm days now that i'm "retired"and have been a cabinet maker/ wood worker for my entire working life, and to be honest with you, i've never seen a bottle "dry up" unless it fell befind the fridge andwas forgotten about for months. living where i do, i have seen it frozen though, plent of times.....that's my bet.

foodstick

When in doubt ........................ DO A TEST whenever I am not sure..or I have a new type of glue..I get the scraps out and glue up all kinds of different type joints and even butt joints which I never do for anything on my airplanes..but it gives you a good way to break it apart and evaluate...

LargeScale88

I built a nosen P-51 20 years ago with Sig Ment. I am using the SAME bottle today on my Smith P-51 and still holding strong!! Its more a fillet glue though.

Jason

JollyPopper

My Feedback: (6)

Since these glues are water soluble before they set up, can't you just add some water to a bottle from which the water has evaporated? Just a few drops until you get the consistency you want? Or not?[]

ocelot31454

As long as the Glue HAS NOT exceeded its freeze/thaw rating. Most wood working glues can be frozen and thawed 2-3 times before the resin becomes unstable. Water only thins it out. Any glue that the rosin has been frozne more than a couple of times will LOSE it's bonding strength. I have a wood working hobbie shop and have lost several bottles of glue because the furnace went out and they froze one too many times. You might be farther ahead using Ambroise,Testors or SIG wood model cement. It may cost more per oz but I think it holds better and it doescurefaster.