You guys that use Epoxy glue?

Those two part, five minute Epoxy, dual tube, glue sets beat me to death.
One tube or the other wont work.

There are pumps for each part of the Epoxy glue. One for each can. How effective is that for making a good glue mix?
Where do you guys (here in the states) get your Epoxy and pumps?
Dick.

 

The 5 minute and other fast setting epoxies, packaged in those ready to squirt tubes aren't worth a damn, don't even think about using them. They rarely eject the proper amount in the correct ratios and the fast set time insures it's very brittle and useless in the marine environment.

Pumps are for novices to be frank. If you do a lot of work, then you'll wear out a pump quickly, so adopting a different method is required. I use several different epoxies and they all have different ratios so I have to pour to predetermined volumes. This is the safe way and the accurate way. For small batches, I'll use a syringe to measure out resin/hardener.

Mixing should be done slowing, by hand, unless you have some skills and are mixing large batches. Large batches aren't practical for the novice.

If you want pumps, each formulator will offer pumps, but if you're really clever you can use veterinary and medical supply houses, who'll offer generic pumps. A common size would be a one ounce stroke pump. It usually fits the standard one gallon screw on lid and one full stroke of the primed pump will produce a single ounce of whatever is in it. Naturally, you have to keep track, so a 3:1 epoxy need the appropriate amount of pumps to keep the ratio correct. The first time you miss count, you'll be so pleased with yourself, probably talking in several colorful languages to yourself, as you remove the uncured goo and start again.

 

Actually, these twin tube epoxy syringes aren't so bad, but there are 2 issues.

Most of them have been waiting too long for a customer, just like penlite batteries. If the "use before date" isn't very far in the future, let them sit for the next customer.

Another point is that fast curing epoxy is only good for mechanical bonds. The surface to bond to must have craters, crevasses or otherwise shaped holes to rub the stuff into, otherwise it will come off when some force is applied.

 

I have always thought that measuring ratios of epoxy by weight would be the ultimate. You make a balance scale with a very fine pivot (say, a pair of ball bearings like a router bit uses). The scale has one arm at say five times or three times the length of the shorter arm. It always balances horizontal when the ratio is correct regardless of the quantity. It's conceivable even ultra small amounts could be accurately measured if the pivot bearing is low friction enough.
Calibrating the scale would be a cinch. Just use two or three or five (or whatever ratio) of any object (soup can, quarters, whatever) and balance against one unit of the same thing. Measurement from the fulcrum would also work.
A sliding weight can be used to compensate for the scale's arm weight so that the arm is exactly horizontal once adjusted to the desired ratio. No matter what, this scale would be far more accurate than volume measurement in any case. I'd make mine from an aluminum arm and two baskets on triple chains.
I'm guessing this already exists?

 

Yes, it seems but, for me, there is more innacuracy in the remains in the measuring container than wud make it worthwhile to go to the trouble of balancing. Digital scales work very, very well and much of the time I find I'm not using those either. For me, mixing larger batches, when needed, removes more of the error than can be done with nth degree measuring.
I tried Gorrilla's twin tube epoxy stuff and it wasn't worth a crap - even using the entire tubes to lessen unequal sqeeze-out (specifically, it was used in an area that was going to get wet and it seemed to absorb water and lose its grip). I agree with PAR that these things are for hobby.

 

I sure like Alan White's idea of a calibrated balance scale. Especially for us Hobbyist's who very often make up small quantities.

Mark has a good point about it too, so overcoming Mark's (dirty container) objection would make that Balance scale the right tool.

For us Hobbyist's two identical pieces of Clear glass would be the answer. The Scale will tell if you cleaned the glass well enough to use again.

I think I have at least three ball bearings of equal weight.
Ensuring the equality, set two of them in one side, one in the other and mark the spot where the pointer stops as 2:1.
Then put three in one, one in the other and mark the spot for that as 3:1.

I bet I could make something like that out of whatever I have in my barn. Thanks guys!

 

Epoxies are mixed by volume and looking up the weight mixing ratio can be difficult with some resin formulators. It's the volumetric measurement provided on the label or from a pump, not the weight.

For accurate small amounts, use a syringe and "draw up" the precise amount each time. For larger amounts, graduated mixing cups are inexpensive and reliable.

Using a scale is okay, assuming you have the proper ratio. A fast cure that I use regularly here says 3:1 on the label, which is it's volumetric ratio. If I used this as the weight ratio, the mix will be off by over 17% and this is enough to screw up the batch, because weight ratio for this particular resin is 3.65:1. So, yes weight can be accurate, if more trouble then necessary, but you have to use the right ratio.

 

Use a gram scale with 1/10 gram accuracy is the only way to batch epoxies.

 

Sorry Mate, that is completely wrong and dangerous.

A homebuilder has to use a volumetric measure to get a proper mix. The fact, that we builders use weights in a controlled, professional processing, should not irritate a novice, or homebuilder. We get the entire raw stuff mixed, formulated, and prepared for OUR requirements! These can change every week, or every job. How would a homebuilder cope with that?

Stick with the given ratio and you are fine!

Regards
Richard

 

OK PAR, you have me convinced.
Might you suggest a source for these Syringes and marked cups etc that the Epoxy wont stick to?
I dont want to be learning that Foreign Language you spoke of.

Do you use a separate Syringe for part "A" and another for "B" or do you clean the Syringe and use it again?
What do you clean up with? Alcohol, as in Rubbing Alcohol (70%)

 

I LOVE this idea, and will investigate feasibility at work next week. Here's my take of the key features:

1) Move the pivot to set ratio. Needs to lock in place once set.

2) Simple zeroing of the scale with different containers. Probably a fixed weight on the arms to get close and one that moves with the turn of a screw like most balance beam scales.


We would also need it to be robust and resistant to to resin, that stuff gets everywhere and isn't promptly cleaned up.

 

You can find good mixing cups in the paint aisle at Home Depot or Lowe's. They have all sorts of useful tools for epoxy, including low-nap rollers. I was mixing some very large batches, so I was using the following:


For both measuring and mixing. The set epoxy you leave in the bottom after a day's work pops right out the next morning and you can reuse. I used sizes from a pint up to 2 gallons or so. I had such a large area to epoxy, the 2 gallon container was the right size for me, but they come in all sizes at Lowes and Home Depot.


These make great tools if you have a lot of epoxying to do, or even if you just want a perfectly mixed epoxy. These I have pictured fit in the small pint mixing buckets you can get from the hardware stores. The mixers can be ordered from Jamestown Distributors.


I found these drum faucets to be the most reliable way to extract epoxy in precise amounts from a drum. You could run the faucet until the resin or hardener reached the proper line on the mixing bucket and be very precise.

I would not recommend using one of these pumps, as they fail when you use them with the hardener and they are much more difficult to deal with than gravity (wen you use the drum faucet):


DON'T USE THESE WITH HARDENER - THEY FAIL!

 

Much appreciated!

The pump **** fails!
Use a proper weight ratio (given only for pro setups) or stick with a good measure of calibrated cups.

Regards
Richard

 

This is one I use frequently for difficult to reach areas, injecting into voids or when I need a precise but small amount. Syringes come in many sizes and shapes. Any veterinary supply firm will have them for giving animals liquid medication. Attach a small vinyl hose to the end and you can inject it into most anywhere you like.

With graduated containers, I prefer those with straight sides, instead of the typical flared. I buy them by the case and the plastic used in both the containers and syringes will let you "pop" out the epoxy once it's cured.

Naturally, if you buy mixing cups from the local big box store, you'll pay a lot more then wholesale by the case, but for a small project this is fine.

For what it's worth, you can get some pretty big *** syringes.

It's safer to use a resin and separate hardener syringe. It's way too easy to contaminate a jug of resin with a little hardener by using the same syringe.

Clean the syringe with a mixture of 45% acetone, 45% xylene and 10% isoproyl alcohol. Clean out the bulk with the plunger, wiping it clean with a soaked paper towel, then draw up and squirt out this mixture. You can save some money with solvents by using white vinegar to clean up with at first, but finish with the solvent wipe and soaking.

 

I'm dumb-founded by the depth of conversation and contradiction here.

I have mixed hundreds of batches of epoxy by simply pouring into cheap, graduated, disposable cups and never had a bad batch.

I've even mixed tiny batches by eye and never had a problem. Mix well... really well, then mix it just a bit more.

Syringes work well too, especially for application as PAR says.

Remember, epoxy has very poor UV resisitance and will degrade significantly when exposed to sunlight.

-Tom