Epoxy bottle re-use and mixing different epoxy resins/hardeners?

DigBaddy

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Glue thread!!! (well, kinda)

I just finished off some BSI 30m epoxy and had a thought to reuse these smaller bottles for the laminating epoxy I have in my shop for when I need to portion out smaller amounts. Using the 1/2 gallon bottles is a pain, so why not put some of that in the BSI bottles? Less waste of things is good, right?

But, then I had a brainwave; is putting different resins and different hardeners together ok? Could I ask the forum without a thread turning into a never ending debate - like where to position an igniter in Aerotech reloads? I suspect that some of the BSI materials, when mixed with the laminating stuff, would change the behavior when mixed into the final product - likely speeding up cure time. That wouldn't be a good thing. I would also guess that BSI hardener wouldn't react weirdly with laminating hardener and same for the resin....but I could test it. Should I attempt to clean the bottles out first? Not sure where to begin with that; acetone, alcohol?
 

rocketgeek101

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Glue thread!!! (well, kinda)

I just finished off some BSI 30m epoxy and had a thought to reuse these smaller bottles for the laminating epoxy I have in my shop for when I need to portion out smaller amounts. Using the 1/2 gallon bottles is a pain, so why not put some of that in the BSI bottles? Less waste of things is good, right?

But, then I had a brainwave; is putting different resins and different hardeners together ok? Could I ask the forum without a thread turning into a never ending debate - like where to position an igniter in Aerotech reloads? I suspect that some of the BSI materials, when mixed with the laminating stuff, would change the behavior when mixed into the final product - likely speeding up cure time. That wouldn't be a good thing. I would also guess that BSI hardener wouldn't react weirdly with laminating hardener and same for the resin....but I could test it. Should I attempt to clean the bottles out first? Not sure where to begin with that; acetone, alcohol?
I'd definitely clean the bottles before. Alcohol is pretty effective at removing uncured epoxy. I would also imagine that soaking the bottles in hot water to soften and make the hardener and resin flow better would make them easier to clean.
 

prfesser

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I have used old Fibre Glast curatives with several epoxies, with good results. The difficult part--not really hard--is the cure ratio. Check the ratio given on the curative you plan to use, and do several tests, bracketing the ratio given by the manufacturer.

For example, the Fibre Glast fast curative that was given to me had 23 phr on the can. That's 23 Parts (grams) curative per Hundred parts of Resin. I made small samples using 20, 22, 23, 24, and 26 phr. And found that 23 worked fine for the US Composites laminating resin I had. Not surprising; although curatives can vary widely, most consumer epoxy resins are quite similar.

Bottom line: try it. Be sure that you've got the right ratio before actually using it on a rocket.

Best,
Terry
 

cls

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New bottles are available, for example from TAP Plastics.
 

astronwolf

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You can get some inexpensive plastic "ketchup dispenser bottles" from places like Harbor Freight and Dollar Store. Your investment in epoxy far exceeds the cost of the bottles, so why mess around?
 

rharshberger

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You can get some inexpensive plastic "ketchup dispenser bottles" from places like Harbor Freight and Dollar Store. Your investment in epoxy far exceeds the cost of the bottles, so why mess around?
Just make sure the bottles are HDPE, LDPE bottles can allow epoxy liquids to leach through the bottle. Most squeeze bottles are either LDPE or HDPE since its more "squeezeable" than PETG and it returns to its original shape better.
 

astronwolf

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Just make sure the bottles are HDPE, LDPE bottles can allow epoxy liquids to leach through the bottle. Most squeeze bottles are either LDPE or HDPE since its more "squeezeable" than PETG and it returns to its original shape better.

Oh my... I transferred my Aeropoxy ES6209 from those awful cans to squeeze bottles a couple years ago. Haven't noticed any leaching. No idea what kind of plastic.
 
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