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Just thought I'd share this in case someone hasn't already thought of it.
I hate to mix up small batches of epoxy with the stupid push pumps that burp, clog up and otherwise are quite annoying. I was wasting a lot of epoxy by mixing batches bigger than I really needed for tiny jobs.
I found these containers with Yorker spout tops, at US Composites http://www.shopmaninc.com/containers.html for about a buck apiece. So I just refill these from my larger containers and mixing is easy. They also have small (2 oz and 6-1/2 oz) graduated mixing containers for .20 and .16 each, that make it really easy to accurately do very small batches with no waste. (By the way, I don't work for US Composites.)
not a bad idea, but again- there's a very simple way of mixing small amounts. For a 2-1 epoxy, just use a straight sided container and mark off a 2 increment line on a stick, then go up one more increment and make another line. Fill the container with resin to the first mark, hardener to the second, mix and go.
Vary the marks to suit the ratio needed
I cut the centers from spray can lids and use that little tiny straight sided container that remains. I can mix about a teaspoon full accurately and quickly.
By the way- it WON"T work with a sloped sided container- ratio will be wrong.
Meade Gougeon showed me this trick at an Experimental Yacht Association meeting in St Petersburg Fl in 1978 or 1979. I've used it ever since
While we're on the topic - here's how I happened to do it (this was pre-forums, so I didn't have a chance to stumble upon better ways):
I bought a huge bag of those cheap, clear plastic "beer cups." Then, since the sides are sloped, I used water to measure out four different sets of ratios in one of the cups (i.e. S, M, L, XL). I marked these with a permanent magic marker in various places around the cup. I marked the resin as the first line, and the hardener as the upper line to avoid having the hardener stick to the outside of the cup and throw off the ratio (I was using System 3 which had a 2:1 ratio).
Then I put a clean, identical cup inside the marked cup, and transferred the marks (they move slightly because one cup is inside the other). This new cup then became my "Master" cup (I threw away the first one as it could have caused dangerous confusion), and when I wanted to make a batch of epoxy, I slipped the marked cup into the cup-to-be-mixed-in and (reading through the clear plastic) made the appropriate marks on the soon-to-be-filled-with-epoxy cup.
It sounds complicated but was actually easy and cheap. Just one way to skin the epoxy cat. I still use that method.
The squirters are a good idea. I've been using small graduated medicine cups for small batches. I probably got them from US Composites, but I don't see the paper ones I have on the site any more.
I know what you're saying about the burping plastic pumps, the 4:1 mix's hardener is so thick it nearly won't pump and I had a problem with a slow drip that stained a bulkhead. I've developed enough finesse that I can get them burped before throwing off my mix, just have to 'feel' if they are full before taking a full stroke on the pump.
I always hated those useless mini-pumps, and now I freely admit that I am hopelessly spoiled by my West System fixed ratio gear pump, which guarantees perfect mix ratios in any quantity, including small batches. This pricey item is well worth its cost for any serious epoxy user. Of course, it only works with 5:1 epoxy systems.
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Forum Founder--No Longer Participating
Tim wrote:I freely admit that I am hopelessly spoiled.
The rest of the post was superfluous.
CharlieJ wrote:not a bad idea, but again- there's a very simple way of mixing small amounts. For a 2-1 epoxy, just use a straight sided container and mark off a 2 increment line on a stick, then go up one more increment and make another line. Fill the container with resin to the first mark, hardener to the second, mix and go...
By the way- it WON"T work with a sloped sided container- ratio will be wrong.
The math part of my brain isn't even remotely awake yet this morning, but I think this still works so long as the stick is laying on the sloped side of the container, not standing vertically.
Your stick can be leaning but the sides of the cup have to be vertical. A leaning stick lowers the amount that each line on it represents, but the ratio stays the same. Sloped sides of the cup make any linear measurement wrong. The volume each linear increment represents is ever increasing as you fill the cup. You could create a linear scale on a stick for a particular sloped side cup if you are willing to use measured volumes added to the cup to determine where the lines go.
I use the gear pump.
Dave Finnegan
builder of Spindrift 9N #521 'Wingë'
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