T&L Publications

Regarding hot melt glues, keep in mind they are ethyl vinyl acetate (EVA)- the same material used to laminate solar modules glass panels together. The have good long-term UV resistance, and don't noticeably degrade, or darken in sunlight.
Hobby hot melt can be bought that is "slow-cure", that is, it will stay liquid longer after dispensing to allow working it.

psycho wrote:As for melting large quantities, anyone know if you can put it in
a microwave or toaster oven without it breaking down or, more
importantly, fuming the oven with toxins?

Go to a craft store and get a glue pot instead of a glue gun. Crafters use
the pot in conjunction with a brush when fine applications of glue are
needed. You could melt and pour out of the pot to form specific shapes.
The best part of this method is that you take the leftover melted/solidified
glue and reuse it! Just remember to skim any gunk off the top.

CeaSaR

Hi again,


Just a quick note about the pricing...

I had gotten a bunch of sticks at a craft store on sale, and i think
the craft stores have sales on these things now and then. Maybe
keep an eye on the papers for a sale, or maybe even check out
their web site now and then. When a sale appears, bring a box
with you to put them in as they will make you put them in a bag
which isnt as nice.

My measurements indicate that each stick contains 0.6 cubic inch
of material (7/16 diameter by 4 inches long).

The name of the store i got mine from was AC Moore, and i think
they have a web site. Im going to check now.

Ok back...checked AC Moore's web site and found they have the
sticks for $3.07 for 20 sticks of the size above. When they have
a sale though the price comes down lower than that.
I had to do a search on the site to find them though.
Oh, i also found 50 sticks for $5.49 too.

I've sure been having fun keeping up with everyone's great ideas!

MrAl, you mentioned using hot glue for capping off tubes of silicone. That gave me a thought about using pure 100% clear silicone for exterior sensor projects. The tubes are fairly inexpensive at any hardware store. The only drawback is that it takes at least 24 hrs. to cure. I wonder if this would last a lot longer than hot glue outside? It sure would be easy to go from a caulk gun to the mold.

evahle

Evale
The higher quality silicones used for exterior caulking usually come with a 30 year life span guarantee and thats in the great outdoors. Of course you can't trust many guarantees in this day and age

Hi again,


Robert:
Wow, that's great. I like to use that stuff too now and then for the
more permanent stuff.

evahle wrote:I've sure been having fun keeping up with everyone's great ideas!

MrAl, you mentioned using hot glue for capping off tubes of silicone. That gave me a thought about using pure 100% clear silicone for exterior sensor projects. The tubes are fairly inexpensive at any hardware store. The only drawback is that it takes at least 24 hrs. to cure. I wonder if this would last a lot longer than hot glue outside? It sure would be easy to go from a caulk gun to the mold.

evahle

Yeah sure, that's a good idea too, but just one small word of caution
here... and this is the type of silicone used for electrical work...
The type of silicone that i think has to be used is the type that is
specifically made for electronic work. The reason is that the run of the
mill stuff eats up the metals used for wiring and component leads
and circuit traces too. The electrical stuff is made not to do that.
At least that's what i've read many times over again.
If you do try some, let us know how it works out if you can.

Hi Robert. You're right, I don't know of too many things these days that last as long as they say. They don't have to worry though, they'll be out of business by then anyway.

MrAl, I didn't think of that! I think I would like to try that experiment. If I do, I'll let everyone know if it lasts 30yrs.

evahle

Hi again,


I guess i meant the more 'current' news about how it works out

I was just being funny.hehe.

evahle

Evahle
Idearly hope you report back in 30 years. I more dearly hope I am still around to read your report!

evahle wrote:I was just being funny.hehe.

evahle

Hi again,


I was too

Since we are on the subject of hot glues, I have a question for you guys. Does any one know the electrical properties of this stuff and specifically the dielectric constant. Also was wondering about the electrical properties of common two part epoxy glue that comes in the stereo tube you get at hardware stores and such. I have seen the hot glue or similar stuff used on a lot of circuit boards for component support, so it must meet some sort of minimum criteria.

Yea, I'd like to know that too. I'm going to try an experiment with a couple of LEDs(with shiney leads) in hot glue, and clear silicone. I'll keep watch to see if the leads start to develope some corrosion. It may be a few weeks though to tell, but I'm in no hurry.

evahle

Hi again,


evahle:
Yes, that's the kind of test i was thinking of. Would be nice to know more
about this as i havent tried anything like this either yet but always
meant to.

Robert:
I'd like to know that too. All i know at this point is that it "works" to
some degree because i have used it before, but i never attempted
to measure any of it's properties.
Perhaps a high pot test would help here. I wish i had my tester
here now but it's in storage.
One idea for a test would be to embed two electrodes into the stuff,
apply maybe 500vdc, then measure the leakage current.
An AC test would be nice too of course to measure the dielectric
constant.
If anyone feels like trying this.......

That sounds like another really good test. I think I'll try to do the test with 120vac household current, and maybe keep the leads about 1" apart, then test for leakage current.

I ran out of my 100% silicone, so I'll have to pick up some today or tomorrow. I would rather run tests on hot glue and silicone at the same time.

One thing to keep in mind is, the glues most likely will have inpurities in them ,and could test differently on each test, or worse(depending on the impurity), short circuit.

evahle