I have a QJ Pyraminx, which was pretty good until a few weeks ago. My friend forced it and accidentally broke it. An edge piece was chipped on the inside part that holds it into the mechanism. This exact piece pops out every solve now, making my puzzle useless.
Any ideas on how to fix it? Or should I get a new, possibly different brand pyraminx?

If it was me with a broken puzzle, I'd do all I can to fix it. A little CA (super) glue with accelerator and a file would do the job. However, if you don't have the tools or materials, I'd say get a good Mefferts version considering the obviously superior quality.

Make sure you buy the right one, though.
I'm not really sure which version mine is, but it has ball-bearings and turns wonderfully.

Somewhat related: a few weeks ago I was just finishing a solve of my void megaminx and a corner just slid off its stalk. A drop of super glue later and it worked fine. If you can't find the chip try filling it.

Do you have any suggestions for something to fill it with?

Sure. You can accelerate superglue, which is what I would do, but it's probably less expensive to buy an epoxy putty. I'd reccomend this putty for small applications like this, as I suggested here. It is a brownish color, not black or white, but it's inexpensive and dries quickly. Make sure you sand or file the surface before applying the putty so that it sticks.

Chandler

Ok, thanks a bunch , but just in case I do end up having to replace it, where can I get a Mefferts Pyraminx?

Mmm... how about from Mefferts?

They have a few types in stock, and a speed Pyraminx available for pre-order.

http://www.mefferts.com/products/index.php?category_new=13&lang_new=en

Isn't it ridiculously fast already?

Sure it's fast, when bonding two surfaces. But if you're trying to fill holes or extrude, liquid tends to get trapped under the hardened surface. Accelerator causes the chemical to dry whether it's touching anything or not.

QJs are pretty cheap enough. If you're feeling adventurous, you can always mod it into a Junior Pyraminx:
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