I apologize for the non-jewelry-related question, but I know there
are folks out here who are chemists and such who certainly know more
about glue than I do. I need some adhesive advice.
I need to repair a plastic part inside my dishwasher. The hook that
holds the soap compartment latch closed is cracked, but not yet
broken off completely. It’s not replaceable without buying a whole
new door for the dishwasher. That’s just not going to happen…
I’ve got on hand 330 two-part epoxy and also heavy-duty gel
cyanoacrylate with a spray accelerator. Which of these adhesives
would be better for the hot, wet conditions inside a dishwasher? Or is
there another glue that would work better than these? Private replies
to conuremom AT comcast dot net are suggested so as not to clog the
list. Thanks in advance for any help you can provide.
I need to repair a plastic part inside my dishwasher. The hook
that holds the soap compartment latch closed is cracked, but not
yet broken off completely. It's not replaceable without buying a
whole new door for the dishwasher. That's just not going to
happen...
First off, I’m not an adhesives specialist, but I have tried glueing
plastics many times, with various concoctions all of which were
recommended. For parts that were not subjected to stress or heat,
the repairs worked pretty well, but parts that were subjected to
stress or heat (such as your soap latch) failed miserably; sometimes
immediately and sometimes several weeks later.
For the problem parts I’ve developed a “patch type” solution where I
first use glue, then stitch the broken part together with thin
stainless steel wire. The wire is 0.5mm diameter and fairly soft so
it can conform to the shape needed.
I first use the recommended glue to fix the part together again,
then comes the stitching. Conceptually, I would like to use the wire
as a thread to reinforce the glue, but obviously I can’t use a
needle. So I use a small drill to make holes where I would push a
needle if it was possible. I then thread the wire through the holes
and pull it tight - sometimes it’s necessary to cut a shallow channel
to allow the wire to be recessed. When I’m satisfied with the
“sewing” I then apply adhesive over the stitches so that the whole
join is effectively wire reinforced adhesive. I’ve even used the same
technique on cast zinc castors on a table.
Here is one of the best adhesives for plastics, I have had better
luck with it than others. The handle on the radial arm saw crack in 3
pieces. and it is still holding. Don’t let the site name and other
uses/trades scare you off.
Great adhesive used for keep it together for eternal rest
What adhesive to us in a dishwasher? I think I’d skip on the
cyanocrylates and most two-part epoxies as they will fail with the
repeated heat and water contact. You might look at JB Weld, however,
it’s a two part epoxie that contains powdered metal. It’s used for
repairing metal and other materials that subsequently see hard use.
It can be found in most hardware stores.
Take a look at the label and see what it says about extended water
contact with chemicals such as dish detergent. Otherwise, you might
consider heading down to your local boat and marine dealer and ask
around about what is used in that industry.
I agree that J.B Weld would be your best bet to try. We put it on
the radiator of one of our vans, and it lasted forever! lol
We’ve used it for quite a few things, busted water pipes, cracked
gas tank and I can’t even remember all of the things we’ve used it
for just to buy us time. But, in most cases it’s bought us way more
time than we needed.
I personally would do as Gary suggested, and basically stitch the
part together but instead of using stainless wire, I’d use heavy
Dacron thread (Dacron doesn’t stretch). It’s really strong and is
certainly easier to stitch with. You can find it at most hobby
shops, it is sold as “1/2A control line”, it’s used on those little
Cox control-line airplanes. Any fairly strong and thin thread or wire
will work, just don’t use iron binding wire as the hot, wet
conditions will rust it away in no time. I would use long setting JB
Weld on it, just enough to fully coat the stitching and fill all the
holes.
The only other advice I would add is to drill a small hole (#70 drill
bit?) at the very end (beginning?) of the crack. This is called
stop-drilling and it basically stops the crack from progressing.
This stop-drill and stitching procedure is used for patching cracked
Plexiglas aircraft windscreens and is an FAA approved repair
procedure, so you know it will hold well. Works with any cracked
material as well and is very effective when used with the bonded
stitching as Gary recommends. Just make sure there is no crack
extending anywhere past the stop-drilled hole (or the crack can
propagate even after stitching and bonding), slightly roughen the
surface, a little rub with coarse sandpaper is all you need, stitch
it up and clean it thoroughly (wipe it down with some alcohol and
air-dry) before bonding. Might very well outlast the dishwasher.
There is also a marine epoxy, available at the hardware store.
Remeber, the original question was about sticking plastic - by its
very nature, plastic is flexible and cured epoxy is not. Also, the
plastics used in the manufacture of domestic equipment are often PVC
based to make them more durable and this is a greasy plastic.
Consequently, an epoxy is not likely to provide a long lasting
solution if, indeed, it will stick at all. One solution which I have
found recently is flexible superglue like this http://tinyurl.com/yf8rsjo
and this seems to repair almost everything - including the door
handle of my refrigerator which no other adhesive would touch…
Yah! Stitching or binding is the way to go for my money. I’ve got a
Bosch dishwasher in which a dinky teeny weeny bit of plastic broke
but caused a rather large assembly to fall off its proper place (The
upper whirly-jigger support arm) A new one would take 6 weeks and
multi dollars to replace it because they wouldn’t sell a mere "part"
but insisted on selling the whole assembly as a unit. A pox on that
said I. I ended up lashing the whole assembly back in place with
soft brass wire - quite thin stuff, maybe 24 gauge - you can buy it
in hobby shops on little spools for cheap. To make a long story
short, this haywire repair is going into its third year with no
visible corrosion or weakening of the wire. If the wire did fail it
would be relatively easy to unwind the remnants and do it over again
because there’s no glue involved which might make the repair
difficult to re- do. It all depends upon the shape of the pieces
you’re dealing with as to whether you can figure out a lashing
that’ll have something to hold onto and stay in place. You might have
to drill some holes for that purpose, to make anchor points, but, for
my 2 cents worth, I wouldn’t bother with any glue if I could avoid
it. Look at some of the ways sailors lash things together or how the
Japanese lash together pieces of bamboo very neatly for garden
structures. It can be quite pretty and you might catch yourself just
sitting in front of the appliance with its door wide open so you can
admire your work.
Remeber, the original question was about sticking plastic - by its
very nature, plastic is flexible and cured epoxy is not. Also, the
plastics used in the manufacture of domestic equipment are often
PVC based to make them more durable and this is a greasy plastic.
Consequently, an epoxy is not likely to provide a long lasting
solution if, indeed, it will stick at all. One solution which I
have found recently is flexible superglue like this
http://tinyurl.com/yf8rsjo
Ian, THANK YOU!!! I’d before never heard of such a thing as flexible
superglue.
After examining the door latch more closely, none of the other
creative suggestions I received from Orchidians would have worked. The
part that was breaking was too small to ‘pin’ with wires, plus it was
extremely awkward to work on because it was attached in approximately
the center of the dishwasher door. Hard to reach, even harder to see
with middle-aged vision.
I ordered some of that flexible cyanoacrylate from an ebay seller.
It arrived Friday night. Last night I applied it to the cracked part.
It wouldn’t dry, until I used some accelerator spray on it (from a
totally unrelated CA company’s kit). Luckily for me it worked on
this glue. I let it sit over night and just ran the dishwasher a
little while ago. The soap door latch works as intended again. Even
with the machine still hot and steamy inside, the glue join feels
quite solid.
Virtual chocolate chip cookies for you, dear Ian! :')