# JB Weld



## Submachine (Dec 13, 2018)

I thought I would start a thread for different ways to use my favorite expoxy JB Weld

My most recent use was in trial assembly of metal components.  I wanted to do a trial assembly, but I need it to be a strong bond.  JB did the trick.  Afterward, use heat gun and the pieces fall apart.


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## markba633csi (Dec 13, 2018)

I've used it for lots of things- I repaired a badly cracked interior plastic door panel on a 98 Corolla with JB and little pieces of metal hardware cloth.
I layed little bandages of the cloth over the cracks and imbedded them with the epoxy.  Worked great and saved money too.
mark
PS heating the JB with a light bulb makes it cure better with no stickyness


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## Shootymacshootface (Dec 13, 2018)

I have successfully repaired aluminum fuel tanks that actually had holes in them from deep pitting, both gasoline and diesel tanks. I did the fuel tank of the boat in my avatar over 10 years ago. Fill the actual holes and deep pits with JB Weld, then a layer of fiberglass to protect the repair and the rest of the tank bottom.


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## Bamban (Dec 13, 2018)

Used it to bed my M1a.


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## hman (Dec 13, 2018)

I've had great success fastening sheet metal parts together with JB.  It really helps to lightly sandblast the mating surfaces ... seriously improves grip strength.  I've also used it to fill in "oops" holes in ~.060 aluminum prior to painting.  Lightly chamfer both sides of the hole, so the JB will have a "head" on both sides to hold it in place.


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## Submachine (Dec 13, 2018)

Bamban said:


> Used it to bed my M1a.


I have the Polytec version.  What is “to bed” ?


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## C-Bag (Dec 13, 2018)

I've used to for all kinds of stuff. My most extreme was while in college I rebuilt my 66 VW beetle with the original 1300 engine. As I was hauling the parts in the garage for the final assembly I dropped one of the cylinders and broke off 4 fins. 1300's are rare and I was broke so I JB'd the fins on. I kept waiting for a problem or to hear the rattling of the fins, but when I tore it down at 120,000mi. They were still intact and there was no sign of the cyl have a hot spot or anything. Remarkable stuff.


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## Bamban (Dec 13, 2018)

> I have the Polytec version. What is “to bed” ?



Bed the heel, side, and front of the receiver in the epoxy. End result, the receiver is set in epoxy, so movement when the rifle fired.

The Polytech are very nice copies of the GI M14 dimension wise. I have a couple of them, I will re-barrel one into 6.5 Creedmoor.


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## pontiac428 (Dec 13, 2018)

Many years ago, a friend of mine casted a block of JB Weld and milled an integral barrel and receiver out of it. Came up with a working .22 LR single shot monocoque pistol made of 90% JB. He's still alive and has all of his fingers.

(from mobile)


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## coherent (Dec 13, 2018)

The original JB Weld was definitely high temp heat resistant. I remember using it to fix a crack in a thermostat housing mounted to a engine block on a 327 chevy engine. Never leaked until I sold the car a year or so later. Now I can afford the right part so haven't tested the newer mixes for such extreme projects, but for general epoxy "fixes" it's not a fix all, but when used within reason it's never let me down.


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## kvt (Dec 13, 2018)

Cracks in a auto trans case while I was in High School.   was still going a few years later when I was in town.


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## eugene13 (Dec 13, 2018)

I've used JB to glue all thread into concrete basement walls and floors to attach stuff, area wells, shelving, gun safe.


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## markba633csi (Dec 13, 2018)

It does seem that the new product is slightly different than the product from years gone by- is it better? worse? Hard to say, still seems pretty tough, looks as though the color has changed a bit perhaps
Mark


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## Submachine (Dec 13, 2018)

Seven years ago I used it to repair the gasket on a front loading Maytag washing machine.  Still using that machine.


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## eugene13 (Dec 13, 2018)

Submachine said:


> Seven years ago I used it to repair the gasket on a front loading Maytag washing machine. Still using that machine.


Just reminded me of the washing machine pump impellerI I repaired, it lasted until the motor quit.


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## Submachine (Dec 14, 2018)

Bamban said:


> Bed the heel, side, and front of the receiver in the epoxy. End result, the receiver is set in epoxy, so movement when the rifle fired.
> 
> The Polytech are very nice copies of the GI M14 dimension wise. I have a couple of them, one of them I will re-barrel into 6.5


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## Submachine (Dec 14, 2018)

big tubes (10 ounces versus 2 ounces) of JB Weld at Amazon.  It’s a lot cheaper than using lots of the little ones.


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## ch2co (Dec 14, 2018)

“big tubes (10 ounces versus 2 ounces) of JB Weld at Amazon. It’s a lot cheaper than using lots of the little ones”

Does anybody know the usable lifetime for the big tubes? 
  2-3years maybe??


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## Cooter Brown (Dec 14, 2018)

I have used it to replace stripped out threads in a piece of cast aluminum. Drilled the hole out, filled it up with JB weld and drilled and taped it for a 1/4-20 screw... I also cover my boots in the stuff when they start coming apart...


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## Submachine (Dec 14, 2018)

Sorry, bad post and cannot figure out how to delete


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## Submachine (Dec 14, 2018)

Cooter Brown said:


> I have used it to replace stripped out threads in a piece of cast aluminum. Drilled the hole out, filled it up with JB weld and drilled and taped it for a 1/4-20 screw... I also cover my boots in the stuff when they start coming apart...


Ha - never had a bottle last more than six months.  It’s an expoxy..lasts a long time.


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## kvt (Dec 14, 2018)

Some how the tubes get separated and can only find one or the other when need them then have to go get a new batch.   Gremlins in the house/shop.  Never though about it for shoe repairs.


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## markba633csi (Dec 14, 2018)

I think it lasts for years if not mixed. 
Wonder if we'll all get free tubes for participating in this thread
M


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## pontiac428 (Dec 14, 2018)

ch2co said:


> “
> 
> Does anybody know the usable lifetime for the big tubes?
> 2-3years maybe??



I have been back and forth between living stateside and cramming my stuff into my cargo container in storage and living overseas for the last 20 years. I recently used a previously opened pack of JB-Qiuck to make several small repairs. Everything worked out, just needed a little extra cure time. That pack of JB probably came from HF in 1999 and was opened the same year. Heat cycled the extremes of Nevada climate for 17 years. Still worked. I did not expect that. 

Sent from my SM-T800 using Tapatalk


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## Tim9 (Dec 14, 2018)

When I had my auto repair shop I would occasionally get a car in for repair in which the harmonic balancer bolt was left loose on the crankshaft. These vehicles would have a destroyed crank and balancer where the pulley was pressed onto the crankshaft. 
 Proper repair was new crank and harmonic balancer. Needless to say the vehicles weren't worth the cost involved and in almost every case... the owners were scraping by week to week, barely paying their rent. A new or reman engine was a dream for these customers. 
  Long story short, I cleaned effected mating surfaces and loaded it up with J-B Weld.... Tightened the bolt securing the the balancer to crank and let it dry 48 hrs. 
  Of course, I informed the owners that this wasn't kosher and it's at best a patch. I also let them know that the engine crank was now welded to the balancer and they'd need a new motor. Forget about getting it off once I JB'd it. 
  I must have done 5 of these patches over the years. 
  I don't think a single one failed. One of these "repairs" was even on a diesel engine and the customer was still driving that car 4 years later. That's impressive because diesels put out incredible vibrations. 
  JB is impressive stuff.


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## RJSakowski (Dec 14, 2018)

Epoxy should keep virtually indefinitely if not mixed.  If the resin or hardener crystallizes, it can be rejuvenated by heating  with a heat gun.


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## bhigdog (Dec 14, 2018)

I made a complete set of dentures, upper and lowers. Worst part was holding them in place on my gums until they cured but the fit was perfect. They worked great but I did look like Hell.   ............................Bob


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## ch2co (Dec 14, 2018)

Thanks guys. I can just order the 10 ouncers and not worry about it’s longevity. I have several types of locktite that are over 20 years old and they still work the same as if they were new.


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## Submachine (Dec 14, 2018)

kvt said:


> Some how the tubes get separated and can only find one or the other when need them then have to go get a new batch.   Gremlins in the house/shop.  Never though about it for shoe repairs.


Like shoes,


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## Submachine (Dec 14, 2018)

Emergency repair on 4x4 truck with nickle size slit all the way through gas tank. I jammed soap in the hole and capped it in JB Weld.  It lasted monthes, at least. Never heard if they fixed it.


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## eugene13 (Dec 14, 2018)

bhigdog said:


> I made a complete set of dentures, upper and lowers. Worst part was holding them in place on my gums until they cured but the fit was perfect. They worked great but I did look like Hell. ............................Bob


Did it taste bad, or burn?  A former co-worker tried to reline his dentures with RTV, he said it did both.


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## petertha (Dec 14, 2018)

Coincidentally, some model engineering forums I follow have been showing examples of bronze valve cages 'glued' into aluminum heads with various adhesives. Before you load the verbal assault rifles (LOL) some background info. We actually know what we are doing! Well... kind of. These are fussy little buggers. The typical 45-deg valve seat is only 0.010-0.015". So pressing them into the heads with any kind of interference is usually a recipe for distortion, ovaling = valve leak, maybe a junked head - a real headache. Yes the seats might be re-cut & re-lapped, but its much more desirable to establish the seal beforehand, then insert the cage stress free retained with a thin annular film of adhesive.

Where was I? Oh ya, JB weld. Some folks have subjected coupons to fire & fury tests with a blowtorch & wrench, simulating combustion chamber conditions & exhaust port couplings. Apparently JB is standing up better than most of the high temp Loctite's & HT retaining compounds, observing all the gap widths & cleanliness. This was interesting to me, so I intend to repeat. The metal filler is probably helping, but I've had some experience with true high temp resins & they inevitably have to be post cured. So story to be continued.

One thing I can pass on from my RC model days & probably have mixed 10,000 epoxy batches. The smaller the quantity, the harder it is to get the correct 1:1 resin/hardener mix. They are a little bit tolerant of misproportion, but not much. I know when it comes to laminating epoxies like composite structures, even 5% misproportion can cause problems, improper cure or not attaining full strength. So image 5% of a 2 dots of JB. What I find helps is to squeeze them out in parallel lines beside one another so you can eyeball volume better. I use a clean sheet of notepad paper, no used materials especially if they are dirty or greasy.

Another thing is to very thoroughly mix the 2 components. Don't just give it a few swirls & call it good. Don't run yourself out of application time of course, but I would mix for at least 30 secs to a minute, again with a clean stir stick. Some folks have tried gentle heat & post cure heat, but I haven't seen any tangible specs (on JB). For sure this is a known thing in laminating resins.


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## westerner (Dec 14, 2018)

Tim9 said:


> Needless to say the vehicles weren't worth the cost involved and in almost every case... the owners were scraping by week to week, barely paying their rent.


A customer and friend of mine is a great gal, but about as mechanically minded as her cat. She drove the Subaru she has until the throwout bearing grenaded like nothing I have ever seen. The snout the bearing rides on was chewed up bad, and integral to the tranny case. No way she could afford the correct repair. JB  Weld, applied 3 times, smoothed and polished  after the third. Still going, 3 years and 48k miles later. 
Repaired the pitting in a Chevy two-piece intake manifold (Dex-Cool is NOT forever) with the stuff too.
Thanks for the tips to extend shelf life, and curing


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## Shootymacshootface (Dec 14, 2018)

bhigdog said:


> I made a complete set of dentures, upper and lowers. Worst part was holding them in place on my gums until they cured but the fit was perfect. They worked great but I did look like Hell.   ............................Bob


That is f-ing hilarious!  Thanks!


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## hman (Dec 14, 2018)

kvt said:


> Some how the tubes get separated and can only find one or the other when need them then have to go get a new batch.   Gremlins in the house/shop.  Never though about it for shoe repairs.


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## roadie33 (Dec 14, 2018)

I just did a repair on the wifes 2000 Dodge Ram with JB.
The window glass came out of the clips that hold it to the regulator.
I drilled  3 spaced holes through each clip to help keep the epoxy from pulling out after cure.
Then applied the JB epoxy in the clips, attached them to the regulator and shoved the glass down in them.
The epoxy squeezed out the holes and each end. Rolled the window all the way up to cure. I told the wife to not use it for a few days as the temp was in the 40's.
That was a week ago and I asked her today how the window worked and she said like new.
So I got the window fixed and made points with the wife.


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## bhigdog (Dec 14, 2018)

eugene13 said:


> Did it taste bad, or burn?



Tasted like chicken................................Bob


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## markba633csi (Dec 15, 2018)

Just remembered, two repairs on my 97' Jeep Cherokee:  filled and repaired a moderately pitted thermostat housing, and also reattached the rear-view (after roughing up the glass with some fine sandpaper). Held the button in place with masking tape till cured.
mark


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## alloy (Dec 16, 2018)

I have used JB Weld for over 10 years now to seal up transmission housings.   Haven't had a failure yet in over 500 conversions.


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## Groundhog (Dec 16, 2018)

Our little Miller single cylinder welder fell off a truck while driving up the ski mountain. Broke a carb manifold ear off the head. I formed an ear with layers of JB Weld (using masking tape as a form) and installed a Heli-Coil in the bolt hole. Was still running years later when we junked the welder for other reasons.


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## Submachine (Dec 16, 2018)

I am thinking about using JB Weld to create soft jaws for my lathe for one job.  Was going to JB Weld brass squares to the jaws.  Heat release later.

Will this work?  Other suggestions?


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## RJSakowski (Dec 16, 2018)

petertha said:


> Coincidentally, some model engineering forums I follow have been showing examples of bronze valve cages 'glued' into aluminum heads with various adhesives. Before you load the verbal assault rifles (LOL) some background info. We actually know what we are doing! Well... kind of. These are fussy little buggers. The typical 45-deg valve seat is only 0.010-0.015". So pressing them into the heads with any kind of interference is usually a recipe for distortion, ovaling = valve leak, maybe a junked head - a real headache. Yes the seats might be re-cut & re-lapped, but its much more desirable to establish the seal beforehand, then insert the cage stress free retained with a thin annular film of adhesive.
> 
> Where was I? Oh ya, JB weld. Some folks have subjected coupons to fire & fury tests with a blowtorch & wrench, simulating combustion chamber conditions & exhaust port couplings. Apparently JB is standing up better than most of the high temp Loctite's & HT retaining compounds, observing all the gap widths & cleanliness. This was interesting to me, so I intend to repeat. The metal filler is probably helping, but I've had some experience with true high temp resins & they inevitably have to be post cured. So story to be continued.
> 
> ...


For six years with a medical device company, I lived and breathed epoxy.   

Chemically, an epoxy is a compound formed by the reaction between an epoxide (the resin) and an amine (the hardener)  The structure of the hardener determines what the mechanical properties of the final product are.  Typically, the hardener has three reaction sites which make for a highly cross linked product.  In addition to the resin and hardener, additives are used to create the final properties.  

One fact that is little known is that an epoxy that is deemed "cured" actually has only completed about 10% of the chemical reaction.  When the epoxy is first mixed, the molecules are free to move about and re-orientate into a "docking" position.  As the reaction continues, the number of available sites decreases and it becomes progressively harder for the remaining reactants to react.  Typically, a completed bond must break and  new bonds must occur for the reaction to continue.  For the resins which we used, the "cure" time was the order of several hours but the time required for a 90% cure stretched into years.  A newly "cured" resin can actually be liquified by raising its temperature.  As the epoxy continues to cure, the temperature at which liquification occurs rises.  A common practice for us was to cure as close to room temperature as possible until the epoxy set and then cure overnight at 105ºF.  A "final" cure was to elevate the temperature to 230ºF for several days.  At that point, we were probably at about 60% of a complete reaction.

 As with most chemical reactions, raising the temperature decreases the cure time.  As a rule of thumb, 10ºC rise in temperature will double the reaction rate.  Add to this that the chemical reaction gives off heat which can raise the internal temperature significantly for larger mix volumes.

So what does this mean for the casual user?  
First, from our observations, a 5% variation in composition will have no significant effect on final product mechanical properties. For one product, we purposely changed the mixes by 3, 6, and 10%.  Improper mixing and incomplete cure has a more profound effect.  Nevertheless, when I mix small amounts of epoxy for critical applications, I will weigh them on an analytical balance capable of weighing to .1 milligrams. While the densities of the two components are usually close, for critical work, it would be prudent to determine the actual densities as most epoxy recipes are by volume.  
Second, thorough mixing is important to avoid pockets of unmixed reactants,  I will usually use at least a gram of each  to ensure having enough bulk to properly mix.  I mix until I think it is done and then do it again.  The technique that I use is to mix on a piece of plastic sheet (coffee can lids work well) mixing the components with a spatula made from a clean tongue depressor with ine end cut flat.  I then spread the mixture to a thin layer and scrape it into a lump for a second mixing.  I repeat this several times.  Using this technique, I don't end up with uncured epoxy on the plastic sheet which is a good indication that the epoxy that I used was well mixed.  I always leave a small amount for a test sample to check for curing. 
Third, wherever possible, allow the epoxy to cure at room temperature  until hard and the cure at an elevated temperature.  I would slowly ramp up my temperatures to 230ºF.  This process improves the high temperature characteristics of the epoxy and it gives a harder epoxy at room temperature.
Finally, a variety of additives are used to enhance various mechanical properties, iron dust, aluminum dust, and glass microspheres to name a few.   Talc and carbon black are used to control uncured flow properties and as a visual guide to proper mixing.  I have used wood flour mixed with the epoxy to patch defects in wood items.   They will impact the mixing strategy, particularly if the components are mixed by weight rather than volume.


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## Tim9 (Dec 16, 2018)

Thanks RJ. I was always curious as to the effects of heating JB. Your post will go into my notes for future reference. Great info on temp and curing of epoxies.


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## alloy (Dec 16, 2018)

That is really great information.  I've seen where the drying time is much longer at colder temps, and applying it is much easier if the epoxy is at room temp.  I've also seen that they don't always have the same consistency.  One time I got 4 of the 10oz boxes and you open them up and they just poured out.  So thin that I had to throw them away.  I called the company and they were zero help.  I couldn't get past the person answering the phone to ask about it.  

When I applied it in the past it would flow out nicely and give a smooth and mirror finish.  No it  won't flow out and looks rough.  Even using acetone doesn't help.  

When I first stated doing transmission mods and using JB Weld I went on their site and did some research.  Seems that the standard JB Weld is 50% stronger that the JB Weld Quick formula, but drying time is much longer.  I never use the quick formula.

I buy 5 of the large boxes at a time and the best place to get it at JB Tools.  No not kidding. JB Weld from JB tools at $10.71 per box plus shipping of about $7.

https://www.jbtoolsales.com/jb-weld-8280-industrial-welding-compound-2-5-oz-tubes/


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## petertha (Dec 17, 2018)

Re JB Weld & similar 5,10,30 min type 'filled' epoxies in general, all I'm saying is the formulators have put some effort into perfecting the recipe & juggling the fillers & constituents so that equal volume yields the correct mix ratio. So basically do your part to achieve this. I think we collectively beat the thorough mixing advice to death. These are actually pretty robust systems.

Re epoxies for laminating, structural, tooling coats, fixture dough.... high end stuff where $$ are at stake, my advice is read the manufacturers spec sheets. Avoid generalizations and avoid 'what you heard', or at least zero in on a specific epoxy brand/formulation and that includes ambient & cure conditions. Here is an example aircraft structural / laminating epoxy system I'm familiar with that specifies the tolerance on R:H mix ratio- 100:40 +/-2 units by weight. https://m.aircraftspruce.com/catalog/pdf/mgs285tech.pdf

I've noticed many resin formulators don't specify a R:H tolerance. I'm not exactly sure why, maybe RJ knows. I just got in the habit of using a digital scale with resolution appropriate for a tolerance if specified or just strive to hit the number within a few%. Its relatively easy to accomplish & eliminates one variable. Now is it worth fussing about glassing your canoe bottom? Maybe not. Or maybe this is a contributing reason why its tacky for a month, or seems more rubbery than before, or.... or...

Where it gets more critical is low proportion mix and small volume. Coincidentally (and now WELL off topic) I was just looking up Moglice, bedway friction slideway system. Check out those odd-ball mix ratios 91.5 : 8.5 in the paste. So are we obeying engineering principals here and a 0.1 resolution infers 0.1 / 8.5 = 1% hardener mix tolerance? I rather doubt it, but these things keep me up at night  
https://www.moglice.com/assets/01-td-moglice-gb.pdf


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## Downwindtracker2 (Dec 17, 2018)

When Industrial Formulators were making, not the correct word for mixing, G-2 epoxy, the ratio was variable for the harder. 1-1 to 1-2.. You could get flexible to hard. It was aircraft grade BTW. Now that System Three is doing G-2. I don't see that option. Ind For was sold  to System Three.


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## Barncat (Dec 17, 2018)

I used it to repair a rust hole in an oil pan on a 78 f100. Held for four years until it was sold.


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## markba633csi (Dec 17, 2018)

Did you take the pan off and clean it first?  Or were you able to clean well enough around the hole without dropping the pan?
mark


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## Barncat (Dec 17, 2018)

Left it on the truck. As I recall, the front axle would have made it difficult to drop the pan, so just cleaned and slathered it on.


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## petertha (Dec 17, 2018)

Downwindtracker2 said:


> When Industrial Formulators were making, not the correct word for mixing, G-2 epoxy, the ratio was variable for the harder. 1-1 to 1-2.. You could get flexible to hard. It was aircraft grade BTW. Now that System Three is doing G-2. I don't see that option. Ind For was sold  to System Three.



I used Cold Cure resins when they were Industrial Formulators, but not G-2. I know a lot of the woodworkers liked G2 because of the flexibility, handled temperature range better apparently, adhered well to naturally oily woods. I recall it being kind of a special application resin. If you say G2 had that kind of range, then so be it. Its 100:50 pbv now. I have seen flexible epoxies that are formulated specifically for this property, but again at a prescribed RH ratio.
https://www.aircraftspruce.ca/categories/building_materials/bm/menus/cm/epoxy_gflex.html

If you scan the range of epoxy products - laminating, adhesive, coating, potting, gels, doughs... they all have a defined RH mix ratio these days.
https://www.aircraftspruce.ca/categories/building_materials/bm/menus/cm/epoxy_metalset.html

Now many systems allow you to mix your own recipe of hardener, anywhere from 15 min to 8 hour pot life. But you still had to obey the RH ratio, at least the ones I've used.


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## KBeitz (Dec 17, 2018)

I did the same thing on a Jeeps oil pan... Better than dropping the tie rod... 
I put some #2 permatex gasket sealer under the JB-weld so the oil was not touching it.
Working great...

The neatest thing I used JB for was making some acme nuts with it. I drill out a large nut 
and greased my acme rod and slid the nut on. I then packed the nut full of JB-weld.
Works great. You would be surprised how well JB-weld sticks to grease.

One thing I hate is JB-quick. I would not pay a plug nickle for that junk...


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## Downwindtracker2 (Dec 17, 2018)

Peter ,now that you got me thinking, it might have been their G-1, but I think it was G-2. I ,at one time was planning on mixing it hard, adding graphite and Carbosil to it then using it as bearing material. Instead I bought new wiper mechanism. With our rain we wear out wiper linkage bearings.  I keep G-2 around as the handy epoxy. When I glass bed a rifle , G-2 is the epoxy I use with the fillers. I've used their S-1 and the Cold Cure.


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## bretthl (Dec 19, 2018)

I punched a hole in my '69 Volvo gas tank.  Being in school at the time I had no money to replace or repair.  I patched it with JB Weld and a snip from an aluminum beer can.  Drove the Volvo for 100K miles with no leaks.


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## SubtleHustle (Dec 24, 2018)

Interesting posts. I have just ran into a problem with a bandsaw blade guide assembly. I broke it, and am unsure about how to go about a fix. It was brought to my attention that the material is most likely samak. Do any of you, with a lot of experience with JB, think that it might be suitable for my application? I have posted pics. 
	

		
			
		

		
	






P.s. I have never tried JB, at the time of this post.


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## bhigdog (Dec 24, 2018)

Mechanical fix maybe. Jb or any other glue not so much....bob


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## Boswell (Dec 24, 2018)

SubtleHustle said:


> I have just ran into a problem with a bandsaw blade guide assembly



first let me quality that I am just brainstorming as I have very little experience with JB Weld or epoxy glues with metal.  

Could you drill the two parts to accept a pin and then use the epoxy to hold it all together?  You could oversize the holes for the pin to make the alignment easier and the epoxy would fill in gaps.


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## SubtleHustle (Dec 24, 2018)

bhigdog said:


> Mechanical fix maybe. Jb or any other glue not so much....bob


That's what I was afraid of..


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## SubtleHustle (Dec 24, 2018)

Boswell said:


> first let me quality that I am just brainstorming as I have very little experience with JB Weld or epoxy glues with metal.
> 
> Could you drill the two parts to accept a pin and then use the epoxy to hold it all together?  You could oversize the holes for the pin to make the alignment easier and the epoxy would fill in gaps.


I considered this as well, just not sure it would be enough. Might try a mechanical fix, was just sorta hoping that one of you old gurus would be like "hell yeah that'd work", but I was pretty sure I already knew the answer.


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## bhigdog (Dec 24, 2018)

Zamac is spawn of the devil. Cant weld or braze........bob


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## SubtleHustle (Dec 24, 2018)

I might have thought of a fix for it, but I'll keep that in another thread. Thanks for you guys help!


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## markba633csi (Dec 24, 2018)

Here's how I would do it: First, glue the parts back together with JB weld. Then after it's good and cured, drill a hole through both parts from underneath at an angle and JB weld a pin (perhaps made from a piece of coat-hanger wire) in there.  Should be very strong. 
mark


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## Groundhog (Dec 25, 2018)

markba633csi said:


> Here's how I would do it: First, glue the parts back together with JB weld. Then after it's good and cured, drill a hole through both parts from underneath at an angle and JB weld a pin (perhaps made from a piece of coat-hanger wire) in there.  Should be very strong.
> mark


1) I would use a taper pin (with the JB Weld as above) if you have the capability. 
or 2) clamp then drill a tiny pilot hole. Tap the base side & clearaance drill the other side. JB weld it when you bolt it together.


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## KBeitz (Dec 25, 2018)

A small bolt and JB...


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## bill70j (Dec 25, 2018)

The ZAMAC traverse gear case on many Atlas Craftsman lathes is notoriously fragile and breaks easily - and often.

Mine exploded into many pieces, so I used JB Weld to glue it back together and reverse-engineer a new one made of steel.  Worked great.


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## C-Bag (Dec 25, 2018)

I have yet to try Zamak but I know it can be oxy acetylene welded soldered or brazed with the right aluminum solder or braze. Somebody did it to my Zamak ratchet case on my Atlas 7b. I'm hoping to run into a broken ratchet case or other Atlas Zamak piece to experiment with. TinMan sells the solder, brazing rod and flux etc for gas welding aluminum and special goggles. Expensive but it really works as I've gas welded aluminum with his products and it is first rate.


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## Submachine (Dec 28, 2018)

SubtleHustle said:


> Interesting posts. I have just ran into a problem with a bandsaw blade guide assembly. I broke it, and am unsure about how to go about a fix. It was brought to my attention that the material is most likely samak. Do any of you, with a lot of experience with JB, think that it might be suitable for my application? I have posted pics.
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I would be tempted to try JB Weld, I suspect it might work for a long time.  Two exceptions, if safety is involved, or if this is load bearing to any significant degree.  I had a failure on a bandsaw table centerplare I fixed using JB Weld.  I suspect vibration and perhaps cleanliness was the root cause.


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## Tim9 (Dec 28, 2018)

I'd clamp it and then drill 2 small 1/16" drift pins. Taper pins might be better but then again might add another crack so personally I'd just use regular drift pins. Then JB and pin it. i've also used pins and JB for broken teeth on low stress gears. I drill and pin where the broken tooth is and then fill valley with JB.... and then eyeball reform the tooth profile using Dremel tool. Its a real quick fix. Not perfect but gets you up and running. Last time I did this was on a Craftsman wood Planer. Still working. Did it on my lathe also to get it running until I could order/find replacement gear on Ebay.


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