What's best repair adhesive for hard plastics?

I'd like to be able to repair hard plastic manufactured items, but can't seem to find a *good* adhesive. Can someone recommend?
Examples of items to repair would be... cell phone casing, two-way radio casing, telephone casing, PC keyboard, and the like. Here's what I've tried so far...
1) Goop- Works best I've seen so far, but it really doesn't seem to "melt" (weld) the plastic parts together and can eventually separate again.
2) Power Poxy Tear Repair- Works outstanding for vinyl especially, but apparently went out of business
3) Superglue- Works ok, but seems very 'luck of the draw' as to whether it will hold, depending upon the type of plastic.
4) Loctite "plastic" super glue- Comes in two parts, a pre-treatment to brush on, then a tube of what looks like plain superglue. Didn't work at all for me.
5) Loctite plastic expoxy- Comes in the double syringe, doesn't work very good for me, seems like regular epoxly
6) Airplane glue- Haven't tried, really doubt it will do anything Thanks, George
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Back when I did repairs on consumer items, we often used a .025" steel rod to strengthen repairs in plastic. I used a .025" drill bit to drill a hole with the parts aligned. I then applied a two part epoxy (Araldite Fastweld 10) to the part and the rod and assembled the part. After the epoxy hardened I used a dremmel cutting disk to cut the rod. With this method I made some heroic repairs on unavailable parts. Some parts would accept .035" rod. Mike PS I'd like to know what sticks to the plastic Igloo coolers are made from.

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I've come to trust polyurethane elastomer adhesives more, and epoxies less, because of epoxy's lack of resilience. The PU's slight "give" (very slight -- you wouldn't necessarily notice it poking it) prevents it from cracking and makes it less likely to pull away from the adhered surfaces. To make the glue joint stronger (due to increased bonding area) and stiffer, I've made surface joints using a segment of popsicle stick with the PU spread on one side of it and pressed onto the break, like:
======= <-- popsicle stick ------ ------- <-- broken plastic
(popsicle sticks are $1 for a package of 200, and are useful for mixing/shaping/applying a variety of goopy things, from epoxy to plaster.)
I picked up a tube of PU elastomer adhesive from Tap Plastics for $15, and then my wife brought me home two more tubes from Home Depot for $4 each, and as far as I can tell they work just as well as the expensive stuff.
-- TTK
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