I use a 2-part epoxy (E330) too do chip inlay, Most of the time it
works fine but sometimes I get the proportions wrong and the epoxy
does not harden. What methods do others use to assure the correct
proportions? Thanks for any advice.
Ernie
I use a 2-part epoxy (E330) too do chip inlay, Most of the time it works fine but sometimes I get the proportions wrong and the epoxy does not harden. What methods do others use to assure the correct proportions? Thanks for any advice.
I use a small digital scale.
Mike O’Toole
The best way to measure epoxy is by weight. Get a sensitive scale
and use two small disposable measuring trays to place on the scale
and add the resin to one then place the second one on the scale and
add hardener to it till you have the right ratio of hardener to
resin. then mix the two together. This is just about the only way to
always get the right ratio of hardener to resin. Anything else is
just guess work.
Jim
James Binnion
@James_Binnion
James Binnion Metal Arts
I don’t know if E330 comes in the syringe type applicator. Mixing
seems to be easier with that type. As far as getting the the
proportions right. I usually mix a little more hardener to the
amount of resin. Not a lot as the more hardener in the mix the
faster the reaction to full set. Not being that acquainted with chip
inlay and the number of pieces you are doing. A long time ago in a
magazine it was suggested that if you are having problems with the
equal part epoxy draw a couple of squares or circles on the paper or
cardstock that you are mixing on. Making sure they are the same
size, and pair the circles near each other. On another location
place globs of each of the resin and hardener separate of course.
The two parts of epoxy should be usable for a couple hours or all
day depending on the out gassing of the resin. Using a wood coffee
stirrer/craft stick or the large flat toothpick food sticker. Place
the resin in a circle, than place the hardener in the other circle,
with a little more than the resin. Use different sticks for each
parts. Using a new stick take one or the globs and mix together and
then use. after a couple of times of doing this way. You will
develop an eye for mixing. Just remember that the open working time
of the epoxy, will shorten when you add more hardener.
Here is a sight that you might find informative, and useful for
gluing other things.
http://www.thistothat.com Also this site has info on adhesives
http://www.beacon1.com
glen been there done that and still stuck to it!
Sometimes the epoxy cures differently due to humidity fluctuations
in the air. If it is humid and cooler, it will take longer, warmer
and drier and it will cure quicker.
The only accurate way to ensure that your epoxy has the right
proportions is to weigh it.
-k
Karen Christians
M E T A L W E R X
50 Guinan St.
Waltham, MA 02451
Ph. 781/891-3854 Fax 3857
http://www.metalwerx.com/
Jewelry/Metalarts School & Cooperative Studio
I got the best results with plastic measuring syringes. Others have
told me," Always do it by weight."
Augest Derenthal
Cry Baby Designs
Ernie:
I have several places I use epoxy and I have found the best way is
to use a syringe. They are readily available at hobby and craft
stores. Sometimes in Fly Fishing shops. They are available in
different sizes (their capacity).
Draw out however much you need, squirt it out on your mixing pad,
old playing cards flat piece of glass etc., mix and use. Only
precaution is that you will need two. one for the epoxy and one for
the hardener.
Jack
Omni Crafts
John (Jack) Sexton
I make sure to always err on the side of more of the hardener (black
lid). That way it is sure to cure. If you err on the side of less
hardener it will sometimes never cure.
J. S. (Sue) Ellington
http://www.jsellington.com
I make sure to always err on the side of more of the hardener (black lid). That way it is sure to cure. If you err on the side of less hardener it will sometimes never cure.
That’s a mistake. The words “resin” and “hardener” are somewhat
arbitrary. Epoxies are two resins which must be mixed in proper
proportions. Too little or too much of either one will equally reduce
bond strength. Adding too much “hardener” is not better than too
little. Some epoxies, when the 50/50 ratio is not accurate, can loose
as much as half their bond strength if the mix is off by as little as
ten percent. Most consumer epoxies are formulated to be more
forgiving, but the principal is the same. Both componants are
equally essential for proper polymerization. It’s not that one
componant somehow causes the other to harden. It’s that the two need
to combine and react with each other.
You’re best bet, if you want the most consistant joints, is to use a
small gram or carat scale, and actually weigh the two parts, when
you’re using an epoxy type that doesn’t meter both parts for you
(like the dual syringe types). Just adding an excess of the part
labeled “hardener” doesn’t give you a better cure than having less.
If you find that in a given instance the epoxy isn’t curing as fast
or as well as you’d like, add some gentle heat, such as from a heat
lamp, or an oven set very low.
Peter