JB Weld question

[Ray-CA]

Once I mix up some JB Weld “Original Cold-Weld” epoxy, how quickly must I use it? The package says it sets in 4 to 6 hours so if I mix and take say an hour to apply it, is it still going to be usable?

Thanks

Ray

 

[BuffettFan]

How much epoxy are you mixing up that will take an hour to apply?
I would think it would start to skin over before an hour. Maybe mix several smaller batches? I think you would have better results.
Good Luck.

 

[A**holes Garage]

No, that stuff starts setting up in minutes of mixing, it won't spread worth a darn after a couple of minutes.
Cures in 15-24 hours.

 

[Ray-CA]

I just got a return email from JB Weld.

45-minute pot life once it’s mixed.

Ray

 

[Handyfarmer]

I would say use in 5 mins if possible, (this is my experience)

mix up a bit and do a test run,

 

[kelpaso1]

Depends on what you're using. JB Quik Weld set's up in 5 mins. JB regular, you can get 45 mins to an hour of working time. But like others have asked, why do you need a 1 hour working time? More info on what you are doing would be helpfull.

 

[6PTsocket]

There are a number if factors controlling what is called pot life. Heat makes things go faster. The mixed epoxy generates heat. So, the ambient temperature and bigger batches shorten pot life. Keep the unmixed epoxy spread thin. If you do not mix it 50/50 but use more hardener will also shorten the time you can use it. An old trick is to keep the mixed epoxy cold. Mix the epoxy in a disposable tin that is on ice. I once was,working on a boat and tossed the unused epoxy, in a pie tin, on the ground. A few minutes later there was a loud bang. The epoxy cured so fast in the sun that it shattered. I have used JB Weld for years, for small jobs. 45 minutes seems a lot longer than in my experience. That may be the time that it is firm enough not to run but it is a lot longer than you can work it. The best way to gain knowledge is to work with it. The big tubes in a box are a much better deal. TSC always stocks them. Unmixed it keeps for years.

I just got a return email from JB Weld.

45-minute pot life once it’s mixed.

Ray

Sent from my SM-G900V using Tapatalk

 

[c39er]

Within 10 minutes and it starts to be hardening... never 45 minutes unless really cold conditions.

 

[CraigStu]

Mine is more like the 45 min used in my 70 degree basement. It's actually a pain because I am often using it to build up a gun sight and it's hard to keep it from running downward. I need to try the quick version.

 

[Fixin'Stuff]

JB Weld is awesome stuff, in the right application. But like CraigStu, I often find that it takes too long to start hardening and thus tends to sag and drip if you're using it in a vertical application.

Ray-CA, it you need to use it over 4-6 hours you will need to mix several small batches over that time.

 

[EOC_Jason]

Ambient temp & how much you are mixing up plays a huge role...

The twin tube is what I always use... I would say it probably has about 20-30 minutes of good workability. I have no idea about that original putty mix that gets sold like a stick.

You can also look into products by Devcon if you really need longer work time, they have a large assortment of stuff too and is what most 'professionals' use.

FYI, for the guys that say it's too runny for certain things, let it sit for like 10+ minutes after you mix it up before applying it to whatever so it can start to harden.

 

[Ray-CA]

More info on what you are doing would be helpfull.

I'm using it like Loc-tite on some exterior studs and nuts. I've checked with several companies and none of them have an exterior product. So, JB Weld on the threads, tighten the nuts down. Once they've set over night, I double nutted each of them.

Ray

 

[A**holes Garage]

I've used the regular JB Weld to fill and level out some steel surfaces, almost used it like Bondo, but thinner. Thin layers of the regular, long cure JB Weld will not crack or fail when heated in a powdercoat oven.

 

[nes999]

I just got a return email from JB Weld.

45-minute pot life once it’s mixed.

Ray

Pot life includes stiring time. This is something gets newbies in the special effects world often.

"I dont know why it hardened it said I had a 10 minute pot life"

"How long did it you to mix/vacuum"

"Ohhhhhhhhhh"

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[bubinga]

Depends on what you're using. JB Quik Weld set's up in 5 mins. JB regular, you can get 45 mins to an hour of working time. But like others have asked, why do you need a 1 hour working time? More info on what you are doing would be helpfull.

Say, old thread, but can I buy anywhere, just the hardener for the JB Quick Weld?

 

[andyvh1959]

I once used JB Weld in a pinch to fix a cracked block on a 8hp Tecumseh engine. I bought it used, cheap, it had thrown a rod. I replaced the con-rod/piston, did a few other updates. Found the rod had put a cross-crack into the side of the crankcase. So I cleaned the inside of the block, sprayed it down a few times with brake cleaner, wiped it out with Acetone. Then set the block with the cracked side down, and mixed up JB Weld and applied it into the crack area. To help it settle/spread out I applied propane torch heat to the outside of the block and it continued to flow out. Once set I reinstalled the crank to check the flys cleared the repair. Good to go.

I reassembled the engine and ran it for at least ten winters of clearing heavy snows up here in Green Bay. Always started on one or two pulls. Like any epoxy product it all comes down to prep to insure a strong bond.