not all 2 part epoxies...

The temperature while curing makes sense, as with paints and other solvents. I also warm up silicones before applying.

I have no reason to believe semi translucent epoxies can not be brought to a high polish my standard methods? Performed after its fully cured.

Some project thats non related, I'd like to encase a coin in acrylic but that's not possible for me to do. But why not epoxy? Strictly for visual purposes.
No reason you can't polish it but the mixing and cure will be important. Get the ratio right by weight and use a two-cup mixing method. Mix in cup #1 until you think it's OK, then transfer the bulk to a 2nd cup and mix with a clean stirrer. After a heat cure there should be no surface film or blush. No reason you can't encase a coin, but I know they have various casting resins just made for stuff like that. If you use epoxy, be careful of exotherm. It will release heat and can go into thermal runaway if the volume is too much or the cure is too hot. That can be as little as a half ounce, maybe less for some.
Don't know if JB is electrically conductive. Probably not, but the leakage might be high. Not my first choice, but you could measure it.
 
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JB-weld has become more of a brand name for a range of products, these days. But their original epoxy isn't 'considered to be' an electrical conductor. I wouldn't expect it to be an especially good insulator (iirc isn't it metal-filled?) but it may be an adequate one for some applications. I've used it quite often for metal bonding, and it can be quite decent stuff. Though I've suspicions that the max tensile strength needs to be de-rated with temperature, and a lot of places over here seem to carry quite old stock that isn't in the best condition any more.

One of my favourite epoxies over here is Araldite Standard - which iirc has a 90min working time. Sadly slower setting epoxy is getting harder to find in local hardware shops, they increasingly stock multiple brands of only the fast or ultra-fast curing types. I guess people assume fast is good and so make it popular, but in practice these tend to be weaker and more brittle.
 
The metal infused is just what it says, and metal is conductive. waits to observe the surprised looks..

probably, most likely, why chance your electronics?
It looks exactly like the metal infused auto body filler by brand Bondo. Its good stuff, and very strong stuff. Snapping a piece after cure was not possible.
 
No reason you can't polish it but the mixing and cure will be important. Get the ratio right by weight and use a two-cup mixing method. Mix in cup #1 until you think it's OK, then transfer the bulk to a 2nd cup and mix with a clean stirrer. After a heat cure there should be no surface film or blush. No reason you can't encase a coin, but I know they have various casting resins just made for stuff like that. If you use epoxy, be careful of exotherm. It will release heat and can go into thermal runaway if the volume is too much or the cure is too hot. That can be as little as a half ounce, maybe less for some.
Don't know if JB is electrically conductive. Probably not, but the leakage might be high. Not my first choice, but you could measure it.
I drilled out some 1/2" aluminum rivets x4. I filled the remaining voids, its holding on well.

A separate project.

Its kind of fun to play with epoxy.

Id rather find some 1/4" acrylic. But they wanted to sell me an entire 4x8 sheet lol, I can't use all that! A 6"×8" piece would be great though.
 
No reason you can't polish it but the mixing and cure will be important. Get the ratio right by weight and use a two-cup mixing method. Mix in cup #1 until you think it's OK, then transfer the bulk to a 2nd cup and mix with a clean stirrer. After a heat cure there should be no surface film or blush. No reason you can't encase a coin, but I know they have various casting resins just made for stuff like that. If you use epoxy, be careful of exotherm. It will release heat and can go into thermal runaway if the volume is too much or the cure is too hot. That can be as little as a half ounce, maybe less for some.
Don't know if JB is electrically conductive. Probably not, but the leakage might be high. Not my first choice, but you could measure it.
I do use a dixie cup and get proportions and mix right, most importantly maybe. I never tried adding heat to cure before reading this, I would usually just cure at room temperature.

My friend used JB out in a pretty cold day to fix the air cleaner housing on his diesel. Eventually it cured and did what it was intended. As with paints, I will avoid applying it below a certain temperature. Unless its a do or die type of situation with epoxy.

We did paint a car during winter in non heated garage, and ruined a $1500 paint system. It was severe orange peel over entire surface after it hardened. We were teens and too hard headed to take good advice back at the time.
 
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I'm going to experiment with this polished lava rock art thats been around forever, and the entire tube of epoxy.

If I pour slowly by an edge, it might reduce air bubbles. At least that's the quick theory I came up with.

I'd rather have it encased in the resin without encasing the resin in the mold. But that will permanently bond to it.

So lining it with some kind of paper makes sense, then I can grind it off with a high sand count wheel? I don't know how this will go but I'll find out.
 

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I like how this one always gets re - buried.
I got the perfect sized ring box and then I misplaced the head three seconds following.
I will fill 1/3 resin on my first attempt at suspending things is resin, then let set enough to hold it up, then pour the other 2/3. slowly, not to produce more bubbles. Bubbles are usually great, but they have no place here.

I don't much care for yt rash, some of them really are helpful of course, case in point, however I resist. I learned most of the coolest stuff before youtube existed. Remember the days when we used to have to figure it out mostly on our own?


Btw this will get exciting.
 

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In the mean time more goofing off. I added the entire contents, wich was barely enough. I need more. If I used as speaker terminal body.

Check out the texture, it looks like frosted glass. I wanted it to be clear, as long as the insert is visible though.

I'll let it cure several days before removing paper. Adding the hardener separately and less might of resulted in fewer bubbles. I seen hundreds when I expanded picture. It would of poured smoothly the other way.

Encasing the binders was an afterthought, that would of made a mess. A drill is better for now.
 

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Better to drill pilot holes while not full cure, I;m thinking to wait is better for some reason.

It is good and rock solid already , will make a sweet - + binding terminal for completed sub box. Better to drill before or after? I'll go with a guess, to wait to later.
 
To heck with waiting, it was dry enough. I added the JB, its seesm to work better for this, and it looks clearer. If you want to turn something in a keychain.

Its at least 1/4" thick, plenty strong. The flash made the tiny air pockets looks worse than they do otherwise.
 

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Be careful with "large" volumes of epoxy, say more than 25 grams or so. That can be enough to overheat. FWIW, you can degas epoxy by pulling a vacuum on it. You can also degas it with a small centrifuge but you have to be careful not to settle the fillers out if it's not plain clear stuff. Sometimes you can just vibrate it. There are a bunch of resins designed for casting that would probably work better if the volume is large, but that seems to have turned out just fine.
 
The pole terminal was an afterthought.

The resin should be plenty strong and air tight, especially compared to the one that came with the box kit. It weighs approximately 1.5 to 2 ounces by guessing.

Will it be sand able? Right now its still kind of spongy. It isn't necessary I thought it would make it clearer. It will work as is. After drilling it out that is. And cutting the paper edge away.
 

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Will a decent phone holder mount stick on acrylic as good as glass? I figured being non porous then it should trick the little suction cup part.

Update, that resin mold looks and cuts and feels like really ugly acrylic, it continued to cure many more days. When I plunked it in a pail of water it turned all white, but the paper fell off by itself.
 
I like how this one always gets re - buried.
I got the perfect sized ring box and then I misplaced the head three seconds following.
I will fill 1/3 resin on my first attempt at suspending things is resin, then let set enough to hold it up, then pour the other 2/3. slowly, not to produce more bubbles. Bubbles are usually great, but they have no place here.

I don't much care for yt rash, some of them really are helpful of course, case in point, however I resist. I learned most of the coolest stuff before youtube existed. Remember the days when we used to have to figure it out mostly on our own?


Btw this will get exciting.
To remove the bubbles use heat. I’ve used my wife’s hair dryer and a propane torch, not at the same time, to pop the bubbles. Use heat and the epoxy will clear right up.
 
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No reason you can't polish it but the mixing and cure will be important. Get the ratio right by weight and use a two-cup mixing method. Mix in cup #1 until you think it's OK, then transfer the bulk to a 2nd cup and mix with a clean stirrer. After a heat cure there should be no surface film or blush. No reason you can't encase a coin, but I know they have various casting resins just made for stuff like that. If you use epoxy, be careful of exotherm. It will release heat and can go into thermal runaway if the volume is too much or the cure is too hot. That can be as little as a half ounce, maybe less for some.
Don't know if JB is electrically conductive. Probably not, but the leakage might be high. Not my first choice, but you could measure it.
The exothermic reaction is very real and can be dangerous. I was building a fiberglass rocket tube, yes another hobby, and when I was done I put all the left-overs and rags in one spot. I left to go eat lunch and when I came back the garage was full of smoke. I put everything in a bucket of cold water. Close call!