JB Weld not curing properly?

[Pem Tech]

Attached a Aeropac retainer to the HMAS Bonestell Saturday. Squirted out the portions of JB Weld, mixed it up, spread it around the aft of the motor tube and slid the retainer in place. There was a little bit of a bead around the base of the retainer so I smoothed it out into a fillet as best I could. JB cures quickly.
Yesterday I was looking over the attachment and noticed some JB smeared on the outside of the Aeropac. Crud, this stuff is supposed to be rockhard and nearly impervious. In agitation I picked at it with a fingernail and it scraped off!
Quite easily in fact. Concerned I checked the mixing cup and the JB left in the cup is still cured but soft, a wee bit tacky and pliable. A a rubber like texture.
I've torqued on the retainer as best I could and it doesn't budge, but what happens when it heats up?
This is my first experience with JB Weld and it was purchased last week, so it isn't an older batch.

Wazzzup whit dat"????

 

[CarVac]

I don't know where you got the idea that "JB cures quickly" because in my experience, it does not. It stays soft for a few hours.

That said, insufficient curing could be caused by several factors, the most important of which is:

MIX REALLY REALLY THOROUGHLY. Scrape the surface of the mixing stick, and the container/surface you're mixing on, and then scrape them again. And then mix. And then repeat.

 

[Pem Tech]

I don't know where you got the idea that "JB cures quickly" because in my experience, it does not. It stays soft for a few hours.

That said, insufficient curing could be caused by several factors, the most important of which is:

MIX REALLY REALLY THOROUGHLY. Scrape the surface of the mixing stick, and the container/surface you're mixing on, and then scrape them again. And then mix. And then repeat.

Let me clarify, it sets quickly.
The package states "Sets in 6 minutes, cures in 4-6 hours" but that was 48 hours ago. SHould I be concerned about the joint strength?

 

[sodmeister]

I don't know where you got the idea that "JB cures quickly" because in my experience, it does not. It stays soft for a few hours.

That said, insufficient curing could be caused by several factors, the most important of which is:

MIX REALLY REALLY THOROUGHLY. Scrape the surface of the mixing stick, and the container/surface you're mixing on, and then scrape them again. And then mix. And then repeat.

I agree ,mix,mix and when you think you are done....mix some more.

Also ,you should apply some JB inside the Aeropack retainer itself ,and not just the motor tube ,as you may squeeze all the epoxy out if it`s only on the MT.

JB Weld (not the quick set stuff) should stay workable for a good hour +

Paul t

 

[CarVac]

Let me clarify, it sets quickly.
The package states "Sets in 6 minutes, cures in 4-6 hours" but that was 48 hours ago. SHould I be concerned about the joint strength?

Is this JB Qwik (or however it's spelled)?

JB Qwik is not sufficiently temperature resistant for motor retention.

In fact, from the one time I used it, it never hardened. I consider it pretty much worthless.

 

[Pem Tech]

Is this JB Qwik (or however it's spelled)?

JB Qwik is not sufficiently temperature resistant for motor retention.

In fact, from the one time I used it, it never hardened. I consider it pretty much worthless.

Foul language....
It is Kwik Weld....

%^($#! how am I going to get the retainer off to reattach?

 

[CarVac]

Foul language....
It is Kwik Weld....

%^($#! how am I going to get the retainer off to reattach?

Try a hairdryer. Heat it up, which will further soften the epoxy, and then grab the retainer body with something insulating and yank it off.

 

[Pem Tech]

Try a hairdryer. Heat it up, which will further soften the epoxy, and then grab the retainer body with something insulating and yank it off.

I'll borrow one from one of the grrls at work and give it a shot.

Glad I asked and didn't just fly her as is.

 

[jd2cylman]

I'll borrow one from one of the grrls at work and give it a shot.

Glad I asked and didn't just fly her as is.

Got a mini propane torch? Just wave it around the metal, trying not to set the rest of your rocket on fire... On second thought, with the luck your having lately, just stick with the hair dryer :tongue:

Adrian

 

[Pem Tech]

Got a mini propane torch? Just wave it around the metal, trying not to set the rest of your rocket on fire... On second thought, with the luck your having lately, just stick with the hair dryer :tongue:

Adrian

Sadly enough, you have a point. I do have a propane torch that could be turned down...
If it all goes to h*ll you get custody of the Llamas.

 

[troj]

I'll borrow one from one of the grrls at work and give it a shot.

Glad I asked and didn't just fly her as is.

Um, Layne?

You're likely going to make a mess of that hairdryer.

Unless you'd rather one of the women never speak to you again, go to the store and spend $10 on your own hair dryer....

-Kevin

 

[SwingWing]

better yet, get a real heat gun.

Um, Layne?

You're likely going to make a mess of that hairdryer.

Unless you'd rather one of the women never speak to you again, go to the store and spend $10 on your own hair dryer....

-Kevin

 

[Pem Tech]

Um, Layne?
You're likely going to make a mess of that hairdryer.
Unless you'd rather one of the women never speak to you again, go to the store and spend $10 on your own hair dryer....
-Kevin

Not sure what you think I'll be doing with said heating device, but in one particular case that outcome would be welcome.

better yet, get a real heat gun.

OH BOY!!
And excuse to buy another tool!!!

 

[qquake2k]

https://www.harborfreight.com/1500-watt-dual-temperature-heat-gun-572-1112-96289.html

 

[Area66]

No, he have to invite the girl to come to help him, he need someone to hold the dryer .....

 

[dave carver]

https://www.harborfreight.com/1500-watt-dual-temperature-heat-gun-572-1112-96289.html

Low prices and ever improving quality keep me going back to HF. Having things on sale that allow you to add in the 20% off coupon is really nice. Thinking over a few more tools this month ...like an electric chainsaw...

Oh, yeah, HF has their own version of JB Weld and it's the slow harden variety. Worked good for the things I've used it for.

 

[troj]

Not sure what you think I'll be doing with said heating device, but in one particular case that outcome would be welcome.

Trust me, if your hide is at risk, you'll get something stuck to it....

OH BOY!!
And excuse to buy another tool!!!

Now you're thinkin'!

-Kevin

 

[qquake2k]

Low prices and ever improving quality keep me going back to HF. Having things on sale that allow you to add in the 20% off coupon is really nice. Thinking over a few more tools this month ...like an electric chainsaw...

Oh, yeah, HF has their own version of JB Weld and it's the slow harden variety. Worked good for the things I've used it for.

I buy a lot of tools from Harbor Freight. I've rarely been disappointed.

 

[Davidtmp]

I've used JB Kwik to tack fins on when I'm wanting to get it done quick. Never had an issue with it not hardening. That said, I have taken advice and use the JB Weld to do retainers.

 

[Pem Tech]

https://www.harborfreight.com/1500-watt-dual-temperature-heat-gun-572-1112-96289.html

WOW! They are cheap.....

 

[Pem Tech]

No, he have to invite the girl to come to help him, he need someone to hold the dryer .....

I don't think their husbands would approve.

 

[qquake2k]

WOW! They are cheap.....

Yeah, and a heat gun will get hotter than a blow dryer, and direct the heat to a smaller area.

 

[Pem Tech]

As I was warned, the JB Kwik Weld is crap. Decided that a heat gun was something I would not be using very much so I decided to give the propane torch a shot. Encased in goggles and heavy gloves I turned the torch down to as low as a reliable flame would allow and started to gently heat the retainer. After a few minutes and a few funky odors I was able the easily screw the retainer off the motor tube. The JB just balled up and fell off in little squishy pellets. Tomorrow I'll clean the threads/motor tube and epoxy it back on with regular JB weld. Thanks to everyone for your help.

 

[majordude]

I thought heat kicks off epoxy!

 

[rbelknap]

This has got me thinking. I really want to add rail-buttons (with stand-offs) to my Ventris, but since I've already installed the MMT and the retainer, I cant get the well nut in place for the lower button. If I could get the estes retainer off, I could make it work. Would a heat gun soften jb weld (the standard stuff, not quickweld) enough to pull the retainer? Also, would the retainer survive, or would I be replacing it?

(Sorry about hijacking his thread, Layne.)

 

[chadrog]

I don't think their husbands would approve.

That, and you'd likely end up with too much hot air!

 

[CarVac]

This has got me thinking. I really want to add rail-buttons (with stand-offs) to my Ventris, but since I've already installed the MMT and the retainer, I cant get the well nut in place for the lower button. If I could get the estes retainer off, I could make it work. Would a heat gun soften jb weld (the standard stuff, not quickweld) enough to pull the retainer? Also, would the retainer survive, or would I be replacing it?

(Sorry about hijacking his thread, Layne.)

It does, but you'll turn your Estes retainer into a puddle too.

I recommend getting Acme standoff rail guides which may be tall enough for your purposes, and can be surface-mounted without a problem.

 

[qquake2k]

This has got me thinking. I really want to add rail-buttons (with stand-offs) to my Ventris, but since I've already installed the MMT and the retainer, I cant get the well nut in place for the lower button. If I could get the estes retainer off, I could make it work. Would a heat gun soften jb weld (the standard stuff, not quickweld) enough to pull the retainer? Also, would the retainer survive, or would I be replacing it?

(Sorry about hijacking his thread, Layne.)

I'm not sure I understand, Robert. Are you saying there's not enough room between the lower body tube and motor tube for a well nut? What is the diameter of the lower body tube? And Dog House has rail button standoffs.

https://doghouse.blastzone.org/DogHouseRocketry/Rail_Buttons.html

 

[Pem Tech]

This has got me thinking. I really want to add rail-buttons (with stand-offs) to my Ventris, but since I've already installed the MMT and the retainer, I cant get the well nut in place for the lower button. If I could get the estes retainer off, I could make it work. Would a heat gun soften jb weld (the standard stuff, not quickweld) enough to pull the retainer? Also, would the retainer survive, or would I be replacing it?

(Sorry about hijacking his thread, Layne.)

Bad Breath to the Thread Hijacker!!!
Wait, too late for that....

 

[rbelknap]

I'm not sure I understand, Robert. Are you saying there's not enough room between the lower body tube and motor tube for a well nut? What is the diameter of the lower body tube? And Dog House has rail button standoffs.

https://doghouse.blastzone.org/DogHouseRocketry/Rail_Buttons.html

I've got about 1/4" between the BT and the MMT

I have stand-offs, and there is enough room for a weld nut between the BT and MMT. There isn't enough room the get the shank of weld nut past the base of the retainer (by the width of the retainer threads. Argh.)



I could cut a slit in the body tube, and then patch it back up, or I could try filing down the weld nut, but I might mess up the threads.

The well nuts that I have, I wouldn't be able to insert them all the way before they'd but up against the MMT. I know this isn't too big of a deal, since they are designed to contract, but then the 1" long screws I have would be pressing into the MMT. 3/4" long screws are just short enough that I can't engage the threads in the well nut.