How do I bond Rubber to steel?

Hankins

Hankins

Joined
Dec 7, 2008
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Anyone have a fool proof method for bonding Hard rubber to steel?
Have some 80 durometer rubber sheets I would like to use for handle scale material.
What would be the best way to bond it, so it will stand up on a heavy use blade?
 
80 Duro should hold up ok, as there's a lot of neoprene handles out there these days....

You'll need to flatten and rough the side that's touching the steel (I'd recommend bead/sand blasting both the handles (tape off sections you don't want blasted) and the scales...

Then, use an epoxy with a longer cure time (not the 30 minute stuff)..... You should be fine with that. 3m also has some stuff (durabond I think) that will hold anything, just don't get it on yourself......



MT
 
There is a special black epoxy for bonding ruber to steel. IIRC, K&G sells it in their catalog. System Three T-88 is also rated for this use.
Stacy
 
When I did neoprene to steel, I avoided all epoxies. Most are simply too brittle for a material that will flex like rubber.

I eventually found myself in an autobody store and asked what they use to bond carbody accessories to sheet metal on the exterior of cars. he sold me a tube of black adhesive that dries almost the same flexibility as neoprene.

I think mainly you are just sealing...I know the neoprene handles I did hardly even needed to be glued. Even after drilling, I had to drive the pins into the holes and upon test-fitting, it was a bitch to get the handles back off even without glue since the neoprene held the pins so snugly.
 
I haven't tried everything, but I had an application where I had to bond to rubber in a production application. It can be tricky because the wax processing aids used in rubber. We had adhesive reps come out and I even talked to engineers at 3M and Loctite. For our application we had the best luck with a super glue. The best was:

3M pronto CA40H. It is about $20 an ounce.

But we ended up using something by 3bond because it worked almost as well an was much less expensive
 
i have been using neoprene for years on my knives and plain old superglue has worked the best for me. i had to remove a scale one day to replace it and had a hard time to get it off.
 
Thanks for the advice...tried contact cement and it bonded the rubber together very well, still need to try bonding it to steel.
Also tried K&G 24hr epoxy and that worked but did not stand up to the "Whack it against the cement test" very well. held to the steel but there was a clean break at the rubber. No evidence that it had really gripped the rubber well.
Your obsevations are correct a hard/brittle epoxy bond is not compatible with flexable material like rubber.
Will give RTV a try tonight and post the results tomoorrow.
My reservation with Superglue is the whole Moisture/Water and shock issue of it failing as a bonding agent.
 
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