Secondary bonding

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#1

I’ve never had to do structural secondary bonding before. Mainly I’ve used the following. And top being the best

  1. Epoxy/vinyl Ester with fiberglass or Carbon
  2. Jb weld 5 minute quick stuff
  3. Epoxy/vinyl Ester with micro balloons
  4. Jb weld kneed able tube

Now I’m wondering is epoxy and fiberglass best to bond
Or
Would 3m structural adhesive be best then carbon fiber epoxy on top after its cured?

I have no way to test other than bonding both and smacking with a hammer. However primitive that’s the type of impact force things would see since its seat mounting sides like recaro pole position and a fixture like Rotaloc makes, or bighead for you UK guys.

#2

Use a proper structural adhesive. I haven’t tried the 3M stuff, but they are a quality brand so I’m sure their adhesives would be decent.

Carbon and fibreglass is ok for bonding, but to be honest I wouldn’t do it unless you can vacuum bag the bond and get some compaction. A wet lay up structural bond will never be as good as a proper structural adhesive.

#3

Do you just want to fix the Big Head? Or do you want to bond the console to the seat?

#4

Got it. Yeah that sounds like the best thing so far. I’ll still add a few layers over top the base too.

Are you referring to console as the bighead base plate with holes around it? I’m wanting to provide the strongest bond possible really so in case of an accident failure doesn’t happen. Really I guess pull threw on the side is the main issue, because let’s just say the base comes loose over time it’s still torqued horizontally to the seat itself.

You both have been such a big help with my projects. I need to send you guys done Christmas cookies or something, haha

#5

I would drill a hole through the seat and bond a female threaded bighead to the inside so in case of an accident the bighead has to be pulled through the seat. But then the adhesive will just keep the bighead in place and will not take any loads.

#6

Methyl methacrylates (MMA) can have very high elongation, some over 100%. Basically, they are tougher than epoxies. High elongation also helps to distribute the load over the entire bond surface.

Another good attribute is that, generally speaking, surface prep is not necessary. MMA’s solvate many, if not most, plastic surfaces so you don’t have to grind the surface to get an adequate bond.

All that said, I would do as DDCompound posted, unless that would cause other issues like clearance or fit problems.

#7

But be aware, MMA can only be positioned once and can not be repositioned. If repositioned they directly build a skin and will loose their characteristics.

#8

Yeah that’s what I’m aiming toward. I have a female m8 thread with about a 1.25 inch base diameter with holes. The female thread length is roughly 20-25mm I think.

Any links to this MMA substance?

#9

I’m looking at 3m DP8010 and also DP820 specifically.

#10

Sorry mm I found some mma links. Going to do some more research but thanks for the suggestions!

#11

If you want one off the best try Araldite 2031