Is PC-7 the same as JB Weld?

[mancave]

Is PC-7 the same as JB Weld? (Same compound with a different name)?

I normally use JB Weld, but that stuff gets costly since they only sell those small tubes. while PC-7 comes in cans in larger amounts.

[Nate Nagel]

No, PC-7 is much less runny before it sets up than JB Weld, although in my highly unscientific tests, they perform similarly.

Used to be someone (Eastwood? and maybe they still do) included the small cans of PC-7 with a "steering wheel restoration kit" - I've personally used both PC-7 and JB Weld to patch up old cracked hard rubber and plastic steering wheels before painting. Sometimes the runniness of JB Weld is an asset, sometimes it's easier to use PC-7, I tend to use whichever I have on hand, and if I have both, whichever I think is going to make the job easier.

nate

[jamesgang]

Don't know about that one specifically but most two part epoxy's are basica lly similar chemically. The ones with longer hardening times tend to be st ronger. You can mix various things like micro balloons, shredded fiberglas s, saw dust, etc to make a thicker compound or "paste" if you wish. I keep a quart of us composite's medium 3:1 handy. A lot cheaper in the long ru n than small amounts from hardware stores. Keeps for a few years and will pretty much always harden even if it's getting a bit old.

[micky]

No they're not the same. PC-7 is thicker, less runny.

You should probably have both, because each might be better for certain uses, but I use PC-7** almost all the time The only time I use JB is for little things. The smooth surface of JB can be achieved in PC-7 and 11 by wetting your finger and smoothing the surface. (This is why God gave us 10 fingers, so you don't have to stick the same finger back in your mouth. Tastes bad, and who know, it might be poisonous! ) I suppose if 10 fingers are not enough, one could use a bowl of water instead of spit.

PC-7 comes in two 4-oz cans, and yes that's a lot bigger and cheaper than JB Weld. HD only sells a much smaller size (the cardboard tube that opens at each end) but Ace Hardware sells the two 4-oz cans and maybe even two 8 oz cans. I use separate popsicle sticks (Now I'm lazy and I use separate screwdrivers) to remove stuff from each can, so there is no mixing or touching inside the can, and I've had one set of cans at my mother's house last for 20 years without getting old. I also scratch into the lid a line that corresponds to the seam on the side of the can so that I can replace the lid just as it was. This is less important here than with paint, but I do it anyyhow.

I don't know what all JB can do, but PC-7's uses are amazing. It will stick to glass. I used it to patch a hole in the bottom of a pot, then forgot to take the pot off the stove and boiled out all the water, and still the pot didn't leak. (I decided I didn't want to cook food in a pot with such a patch, but that only limits me wrt food. )

PC-7 is workable after it sets, with a file and maybe a knife.. I patched a gear in a electric miixer, like for mixing in a bowl. Then I carved teeth into the patch. That time it only worked for a minute or two, maybe 20 revolutions, until something caught on something and it broke, but that it worked at all was pretty good. I don't think any other glue I have had would have lasted even more than a couple seconds.

I made a cap for my wine sack with PC-7. Big plastic threads on the winesack. I had to use pliers to take the new cap off, but after that it screwed on and off. I don't remember if I put vaseline on the plastic threads before I put the PC-7 on, but usually I do, if it has to be removed.

And the most amazing thing was when I was 23 and living with two girls and a kitchen that was practically a slum. The faucet ran all the time and the 1" or 1.5 metal drain pipe was rusting through and dripping at a place a half-inch or inch long. No valve to turn off the water, so I put the PC-7 on the drain pipe (This was the first time I'd used it) and when the dripping water made it fall away, I pushed it back. and I did this every minute of two for no more than 10 minutes, by which time it had set. And after that the drain didnt' leak. Even though the faucet kept running, slowly. It was incredible.

**PC-11 is like PC-7, but white.

[micky]

I didn't mean to make this sound better than it was. One girl was ugly and cheated me out of my 50 dollar secuirty deposit.

The other girl was sort of pretty and sort of friendly but worthless to me, because she never stood up for me in any of my many disputes with the first (in only 4 months) She was either afraid of the other girl or her lover, or both.

In fact the only good thing that happened to me when I lived there was that I learned how good PC-7 was.

[dadiOH]

JB Weld comes in cans too. You realize it is just epoxy with some iron filings and filler, yes?

[mancave]

While I know it's an epoxy, JB weld will hold up on hot items which epoxy wont. I welded a hole in my tractor muffler, and made that muffler last 2 more years before it had to be replaced. That hole was only about 10" from the engine manifold.

I have never seen JB in cans sold anywhere. I coated a metal "antique" gas tank with it, and had to use 8 tubes which sold for about $5 each. The tank was leak free, but getting rusty, and a replacement was not only hard to find, but costly, so it was worth the $40.

[Scott Schada]

[micky]

I wish people would not put anythign important only in the subject line. I often don't read the subject line, only the article, especially when just clicking Next to read one artciel after another.

AnyhowI don't think they're they same. IIRC JB is little more fluid, and it's not an epoxy is it? It's one substance in a tube iirc

And I tend to use PC-7 (or the white version, PC-nn?) because I started with it, I buy two 4-oz cans, as long as I'm diligent to get any of A into the B can or vice versa, it never getes old. I have had stuff for

20 years that is just the same as when new. And the demonstation coke bottle at the hardware store showed that it stuck to glass.

The leaklng drain had a hole in it as big as a quarter, and the faucet was dripping too so the hole was constantly wet. Nonetheless, I mixed up some PC-7. I used to use popsicle sticks so I could throw them away, but now I use two screwdrivers, one for each can, and I wipe them off afterwards. Maybe that's risky because I don't keep track of which screwdriver was in A and which in B, but I don't necessarily use the same screwdrivers each time.

Anyhow, I put the PC-7 on the hole, probably wrapped it around the entire pipe to keep it in place, but it kept sagging, partly because of the dripping water. I kept pushing it back where it was,and after 5 or

10 minutes, it stayed there. I let it "dry" for a day and it didn't leak after that.