What adhesive suitable for gluing steel and G10 material?

Hi

I need to glue steel with G10 material together. But it is in moving parts environment that constantly see oil for the moving parts. My first thought was epoxy, but can it survive in oily environment in the long term. Any other suggestions?

thanks

Alan

JB weld

Ranger Mike said:

JB weld

Do you mean epoxy? They have others

Thanks

yes
i am very familiar with two part JB Weld in IC engine applications. never has failed me.
Sealing up and filing space..not good to hold a broken connecting rod.

Ranger Mike said:

yes
i am very familiar with two part JB Weld in IC engine applications. never has failed me.
Sealing up and filing space..not good to hold a broken connecting rod.

Just to verify, this is the one. I actually have it at home.

Thanks

yungman said:

I need to glue steel with G10 material together. But it is in moving parts environment that constantly see oil for the moving parts. My first thought was epoxy, but can it survive in oily environment in the long term. Any other suggestions?

Your unspecified temperature range will be very important with organic glues.
Some plastics absorb water and/or oil. They swell and distort, physically breaking the adhesive bond.

For cool environments (≤110°C), and with the right shape plastic, I wind a Kevlar thread around the object, in an open cross-hatch pattern. If that is done while the object is cold, and then wetted with glue, it becomes a constrictive exoskeleton when the plastic expands at operating temperature.

Is drilling and tapping out of the question? (Threading the steel.)

If mechanical fastening is not acceptable, I would try:

1) Epoxy. Clean the steel to bare metal, then wet sand with the epoxy. Sand the surface of the G10, coat with epoxy, then assemble.

2) A high performance adhesive, such as 3M 5200 or Surebond SB-190. I have used both, and they really stick to steel and most other materials.

In either case, I would seal the surface with a coat of paint after the adhesive is fully cured.

But my first choice would be mechanical fasteners.

Baluncore said:

I wind a Kevlar thread around the object, in an open cross-hatch pattern.

Is Kevlar better than carbon fiber?

hutchphd said:

Is Kevlar better than carbon fiber?

I cannot tell. It will depend on the chemical bond between the fibre and the glue. Epoxy bonds reliably with carbon fibre, so does a more expensive repair, that takes longer, but the greater investment lasts for a longer time.

For me, Kevlar is free, because it comes bundled with short lengths of waste optic fibre. It also rapidly wicks and bonds with the cheap cyanoacrylate superglues, that can get a repair done immediately in the field. For example, electrical magneto or switch bodies on tractors fracture and stop the machine. The non-conductive solution is Kevlar, not carbon fibre. The glue must completely saturate the fibre to prevent water ingress later.

Epoxy is a good filler, but not good for close-fitting glue joints. That is because the polymer chains tend to form along the crack, not across it.

Bulk plastics tend to become brittle with time. My aim is to have the cheap brittle plastic become a filler, inside a thin structural exoskeleton. That can significantly extend the life of a product that otherwise does not justify a "forever" fix with more expensive carbon fibre and epoxy.

A bee would use propolis. https://en.wikipedia.org/wiki/Propolis

I will need to search on the propolis reference.
I have made some remarkable plastic repairs using surface carbon fiber (either linearly applied or chopped and randomly spread) This was occasioned by leftover 4 inch carbon fiber ribbons from a prophylactic vertical surface application on my cement block cellar walls which were starting to try to bow under tension (boy that was an easy fix and has remained solid for a decade now.) I use the surface application technique reqularly on plastic (and even on an Aluminum casting for my snowblower. Works very well.

hutchphd said:

I use the surface application technique reqularly on plastic (and even on an Aluminum casting for my snowblower. Works very well.

With an old Stihl chainsaw, with covers made of magnesium alloy, and plastic internals, there is a tendency to crack when trees fall on it. I drilled zigzag lines of 1mm holes on each side of the cracks, laced it both ways with Kevlar, then 5 minute epoxy. The flexibility and acoustic impedance mismatch of the repair must be good, as it has not fractured since, even when it has fallen from trees.

The local Stihl dealer is not happy, because I don't buy a replacement. The old saw is from before the era of the kick-back chain brake, so if I had not fixed it, I would be safer. We have a good long term relationship. I know it secretly wants to kill me, meanwhile, it just loves to cut wood, and to be cared for. They don't make them like they used to.
I keep it keen (with a file) and jealous by having half a dozen other saws, none of which is as universally convenient and reliable.

You are clearly crazier than me when pushed by exigency. I salute you sir.
The epoxy I got for the basement walls (from some folks in San Diego) was quite extraordinary: very long time constant, low viscosity, and seems to to stick to everything. I don't know enough to characterize the product otherwise, but it is the best. Doesn't like greasy plastic but styrene works and polycarbonate too. This is all voodoo to me, but my house is quite pleased with the result as is the snowblower , as am I.

Baluncore said:

Your unspecified temperature range will be very important with organic glues.
Some plastics absorb water and/or oil. They swell and distort, physically breaking the adhesive bond.

For cool environments (≤110°C), and with the right shape plastic, I wind a Kevlar thread around the object, in an open cross-hatch pattern. If that is done while the object is cold, and then wetted with glue, it becomes a constrictive exoskeleton when the plastic expands at operating temperature.

It's mostly room temp. It's something I carry in my pocket only.

OK, this is really what I am using it for. It's for a pocket folding knife.

The knife has G10 scales( outer cover), inside is steel liner on both sides of the blade. The G10 scales are screwed together with the steel liners on the pivot screw and a few screws on the handle. The G10 help to stiffen the handle against prying. I made a mistake of thinning out the area around the pivot area of the G10, so it's so thin that it's not good enough to stiffen the handle up.

What I am trying to do is to glue the G10 scales close to the pivot area to the steel lines so they become one piece to be stronger. The thing is I need to oil the pivot as the blade has to flip open and close.

It's going to be in my pocket when I go out, that's it. It's not any deep science, just I want to beef up the knife.

If the KB epoxy I showed is good enough for the purpose, that it can survive in oily environment, that's all I need.

Thanks

Yes this is the stuff...i use it on engine blocks for race cars. Water passage block. has never leaked or failed with many years heating and cooling. can be drilled but tapping not recommended. You can surround a threaded insert and it will hold in moderate applications. EVERY crew chief I know has this in the pit box.

Hi

I complete it, it feels very secure. Now my question is what stuff should I avoid to keep the epoxy in good shape? Particular chemicals that dissolve epoxy.

thanks

yungman said:

Now my question is what stuff should I avoid to keep the epoxy in good shape? Particular chemicals that dissolve epoxy.

Avoid heat, UV light, ozone, and chemicals used as paint strippers, such as caustics and nasty things like chloromethane.

Hi

Thanks for the help, works great.

I have a follow up question. The JB Weld seems to stay soft and sticky for a while, at least like 15mins or longer. I wonder how long after they are mixed that I can still make slight adjustment and not hurt the final bonding?

Thanks