Joe wrote in
oups.com:

On Oct 31, 12:17 pm, Jim Yanik wrote:
"MLD" wrote innews:Nb1Wi.2576$mv.609@trndny08:





"Joe" wrote in message
oups.com...
My wife put 2 cartons of milk on the same shelf and that proved to
be too much weight for it and both back corners snapped off in
almost identical pieces. I've never had success gluing two pieces
of plastic together to support weight but I'd like to try
something different and see if it works. I'm going to take my
Dremel and drill about 6 holes in each side of the pieces to be
joined. Then I'm going to insert pieces of a paper clip into each
hole to act as reinforcement for the glue to adhere to much in the
same way rebar works in cement. Has anyone had any success with
this? I'm thinking if nothing else it will increase the surface
area of the connection. Any hints on making it work better? I'm
going to use Gorilla Glue to join the pieces because it will
expand into the holes

Different product (soap dish) I cemented paper clips under and
across the broken pieces. I used Phenoseal ( great adhesive
caulking) to put all the parts together. It's been a few years
without failure. MLD

I had a plastic clamp for a clip-on fan break,and I used epoxy and
popsicle sticks to reinforce it;you have to let the epoxy cure for a
week or two before putting it under stress,to get it's full strength.
The clamp has a very strong spring,and it's held up for about two
years now. I used RAKA boat building epoxy and fumed silica
thickener. I tried J- B Weld before that,but it didn't hold up very
long.It seems to be a softer epoxy. System Three or West System epoxy
would do just as well as the RAKA.

The popsicle sticks are stiff and give more strength than a paper
clip will,and epoxy bonds to it better.

Polyurethane glues are crap.(Gorilla Glue)They also foam up,expand
and make a mess.For wood,I guess they are OK.

--
Jim Yanik
jyanik
at
kua.net

That's weird, I was doing some reading last night and it was
recommended to stay away from epoxy for plastic and then someone said
polyurethane worked great on plastic. Confusing. I guess all plastics
are different

You are right.

and some work best with poly and others with epoxy.I've
had great success with Gorilla Glue. I think the people who don't
aren't clamping the piece for 24 hrs.

Clamp plastic and you squeeze out the glue.
Poly works best with wood because it's designed to cure in the presence of
moisture already present in the wood.

I've had the same experience
you've had with JB Weld. Funny, I used it a decade ago to fix a crack
in my radiator that sealed it shut

sealing and -joining- are two different tasks.
You need more bond strength for joining.Lots more for stressed parts.

now I have a problem getting it to
join anything that is stressed, I wonder if they changed the formula.
I'll try the Raka stuff you mentioned, any clue on where I can
locally?



AFAIK,RAKA is only available online,West System and System Three are at
least equal and usually available locally(boat,woodworking shops),but
System Three online has an EXCELLENT trial kit for $10(last I
checked,awhile ago) postpaid,it also has generous samples of various
fillers,the great Epoxy Book,a wonderful guide to using epoxies(a MUST
read,IMO.),spreaders,mixing cups and sticks,and a big piece of fiberglass
cloth.It will have enough epoxy for your application.
**And I don't have any financial association with them.**

I have used their trial kit and loved it.I still have the trial
kit box,book,and some of the fillers.I also get glass cloth from a hobby
shop,you can get very light weight cloths(top finishing) or
heavier,stronger cloths.
You can also use strands from the glass cloth in your repair.

the plastic I dealt with was similar to Bakelite.

your fridge shelf is going to get a lot of weight put on it,and it WILL
need reinforcement.I would use the popsicle sticks,a bit of that glass
cloth on both top and bottom,build it up thick(on the bottom side),and cure
it for 2 weeks before putting it into the fridge.The Epoxy Book will really
help you in this repair,and you can DL it for free from the System Three
website even if you go with West System.

IIRC;www.systemthree.com.


--
Jim Yanik
jyanik
at
kua.net