Terryscustom
640cc Uber Pimp
Sorry I was confused if we were talking about the composite plane or building a Viper (title of thread).
3D Viper build log (maybe)
- Thread starter daman691003
- Start date
daman691003
70cc twin V2
I'm just worried about med ca and longevity.
daman691003
70cc twin V2
It's ur plane terry sorry
Terryscustom
640cc Uber Pimp
Then you need glue between the parts. Wood requires a face to face bond and a little soaking in helps as well. That is why wood planes are built with wood glue or CA. If you use any CA though, DO NOT use hobby shop junk CA. Titebond medium and thick in some areas is great but not cheap hobby stuff. Also you need to use the correct type of wood glue for the job.
daman691003
70cc twin V2
I only use gorilla wood glue and all my ca are Mercury adhesives
Terryscustom
640cc Uber Pimp
Yup, don't use Mercury. It will crack over time, been there done that. Gorilla wood glue is great for most of the build, if you install any type of tri-stock or similar stock or anything in an area of vibration I suggest Titebond Trim and Molding glue. It is gap filling and does not "harden" to any type of brittle consistency so it absorbs vibration. Hysol on engine box is fine if that's your thing but over the whole fuse it will add to much weight.
daman691003
70cc twin V2
Really I thought Mercury was a good high end ca.
Alky6
150cc
Not trying to start a glue war here (LOL), But can you shed some light on the differences between the titebond CA and the hobby shop CA's? Is there a reason why the titebond performs so much better? Thanks for the continuing education.
Terryscustom
640cc Uber Pimp
Mercury is a good hobby CA (and we're talking about medium and tick here, thin is not a structural adhesive except for balsa......then only if used correctly).
OK, I'm no chemist but I do my testing by assembling a simple structure using a consistent method and then do two things:
1 - see how the structure handles different forces like tensile, compression, sheer and twisting.
2 - break the structure using the weakest link and finally break each and every joint and analyse what happened inside the joints.
I do the same thing with wood glues. With all glues the structures are left to dry overnight for wood glues and cure for 1-5 days depending on what their specs say for full cure. Using epoxy and Hysol with wood / plywood (from what I know) is only for gluing two faces of material together. It is not good for edge gluing or beads like Daman was suggesting.
I have used Mercury and found that Jet medium was better at wicking into joints through capillary action. Now I also found both Jet and Mercury as well as other hobby glues also get very brittle. If you make a pool or a line of these and hose them down with accelerator they will get crack or bubble immediately like thin. With Titebond it usually forms a skin and hardens internally. During building I hardly use accelerator though, just a test. I also found Titebond Medium to have the best wicking ability as well. So much so that plywood joints can be clamped and after a bead is laid on it will completely soak into the joint. Others usually leave some on the surface depending on how you apply.
You will find the same characteristics with different wood glues, which is why it is important to use the correct clue in the correct place. It's not a one type fits all deal!! For instance, Titebond original is a great wood glue for face gluing, but sucks at and grain joints. It dries hard and gets very brittle. Gorilla is great for joints, it soaks in some, dries fast and does not get overly brittle. Titebond trim glue dries a little slower, holds well and stays somewhat flexible....not visibly flexible to your eye but structures respond well to twisting forces.
There are others with different results but my top choices that I use for every build are Epoxy, Gorilla wood glue, Titebond molding, Titebond Medium and very selective use of Titebond thick. I do use selective amounts of thin as well when I know a joint is "too tight" for the medium to soak in to the level I need it. In that case I use thin, immediately followed by the medium.