MrRonObvious t1_j9uahxs wrote on February 24, 2023 at 4:42 PM

Reply to comment by dude_no_just_no in I’m building a border around a playground with landscape timbers, and wanting to secure it with something other than rebar. by _aPOSTERIORI

Epoxy does get hot when curing, but I doubt it's hot enough to start a fire. The rebar would act as a heatsink regardless.

I still think epoxy is a better choice, because it needs to bond to both metal and wood, and I don't think Titebond grabs well onto metal.

dude_no_just_no t1_j9ue3px wrote on February 24, 2023 at 5:05 PM

You’re right, depending on the diameter of the rebar hole it probably wouldn’t get too hot. Epoxy would work, it just may not be the best.

Also yes epoxy will adhere better to the metal than many other adhesives. However this is a potted application where cohesion and bulk material properties will dominate the strength. The ribbing on rebar will have to crack through the adhesive before any adhesive strength is tested.

Consider the higher density great stuff (polyurethane foam) for protecting the rebar and filling gaps. It’s designed to help support windows and doors and would probably be much easier to use here

MrRonObvious t1_j9v2qfv wrote on February 24, 2023 at 7:41 PM

"help support" is not nearly the same as "firmly bond to" and if you have ever compared the strength of the two, it's easy to crack off the excess Great Stuff foam, but I've never been able to crack epoxy without using massive quantities of leverage. Plus this will be outside, and UV radiation from sunlight massively degrades polyurethane foam, so that's another reason I would vote against it.