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Does Z-Poxy have a shelf life? I'm near the end of a set of bottles and I'm wondering whether to finish it off or open some new bottles. Any thoughts on this?

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

When in doubt I run a sample batch

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Ken Cierp

http://www.kennethmichaelguitars.com/

I've been using mine for over 2 years.

Steve

Testing is a good idea but IIRC the shelf life for quality ep*xies is much longer than one might think or at least than I thought...

We are currently using a box of Z-Poxy "finishing resin" that is very amber, nearly brown in color and eight years old.... So far with our tests it's as structurally suitable as the day it was produced. Why are we using this brown stuff? Because in a very special repair application the amber color is perfect for what we are trying to do.

I've also been told by one of the best woodworkers on the forum that other than the ambering epoxy has a shelf life of years.

This question came to mind for me just a couple days ago when I was doing some test runs for staining a mahogany neck. I applied z-poxy to the fretboard binding (cocobolo) and to the edge of b/w/b veneer under the headplate on a mockup of the neck to mask them from the stain applied to the mahogany. The z-poxy seemed to take longer to set up than I remembered from previous use and it gummed up the sandpaper when I sanded it the next day. I looked up the shelf life and according to the info sheet, it's one year. https://supergluemsds.com/Docs/PT40%20-%20%20Z-Poxy%20Finishing%20Resin%20System%20-%20PSS%20-%20rev%204%20-%202013.pdf
I bought the z-poxy almost exactly one year ago. I ordered fresh z-poxy which should arrive today. I can compare them side by side tomorrow.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Here's what West Systems has to say:
"Store at room temperature. Keep containers closed to prevent contamination. With proper storage, resin and hardeners should remain usable for many years. Over time, 105 Resin will thicken slightly and will therefore require extra care when mixing. Repeated freeze/thaw cycles during storage may cause crystallization of 105 Resin. Warm resin to 125°F and stir to dissolve crystals.

Hardeners may darken with age, but physical properties are not affected by color. After a long storage, verify the metering accuracy of the pumps and mix a small test batch to assure proper curing."

I had the impression from other threads that West Systems epoxy was different from Z-poxy. Do you think the 1 year shelf life from the Z-poxy info sheet is overly conservative?

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

I have used some that was at least 3 years old. Normal results. Within the next month or so I'll be using some at the 4 year mark. This has not been opened yet and has been at room temp. the whole time, any abnormal results will be noted.
Tom

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A person who has never made a mistake has never made anything!!!

I think I'm going to just through out the little bit that remains and start the "new" bottles. I bought it last year, so it already has a little age on it...

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

With epoxies in general if the epoxy turns cloudy, simply warm it up until it goes clear again as indicated in Hesh's post and you're good to go. Temperature can have a significant effect on cure time BTW. So if it's a little cooler than usual it will take the epoxy longer to fully cure than usual, regardless of whether it's fresh or old.

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Jim Watts
http://jameswattsguitars.com

If you must throw out please mix first before tossing.

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Cut to size.....Beat to fit.....Paint to match.

What Link said. That's a good practice for any two part finish or glue products before you throw them out.

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jw ( o)===:::

My new batch of z-poxy arrived and the card in the box says to use it above 69 degrees. I have a feeling that was the cause of the problem I had the other day with my older batch. My shop was at around 64 degrees. The last time I used it several months ago, the shop was in the seventies. I sanded off the z-poxy application from the other day just now and it came off in little gumballs. I'm going to see if I can borrow a space heater and try again.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Thanks for that, this is good to know. I have been meaning to try z-poxy and would have assumed that the little card about temperature only meant it would take longer to cure, not that it may give trouble curing properly at all. My shop is never over 70 degrees unless I am gluing up top and back braces. I'll remember to warm it up before using zpoxy (when I finally get around to trying it).

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I had the same experience with z-poxy. I applied in my basement and it was sticky still the next day. I moved it upstairs into 70 and it dried out in a few hours.

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Did you move the actual application you made in the basement to the upstairs and then it dried out, or did you move the application process for later pieces of wood upstairs and then got good drying?

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Good question, I should clarify. I removed the tacky z-poxy, reapplied and then moved it upstairs. I used a scotchbrite with some DNA on it to remove the tacky z-poxy. Here is the thread:

viewtopic.php?f=10101&t=46992

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Thanks for the clarification and the link to the other thread. Lesson learned about temperature and z-poxy. Nice looking guitar, btw.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Thanks. It is the first one I've finished. I'm close to putting z-poxy on a new one! Here is the finished product. viewtopic.php?f=10101&t=47540

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From the legal side of industrial waste, mixing the two parts of epoxy together changes it from a hazardous waste to a routine trash item. Saves bucks and the environment.

I have some Smith All Wood Epoxy from LMI and also some general-purpose epoxy, both about 8 years old. They still work okay, although it seems to take a little longer to cure completely. It gets hard, but has sort of a sticky film. The Smith says it has a one-year shelf life, so I'm a little skeptical about using it on a guitar.

Sent from my SM-T350 using Tapatalk

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Pat

Just used some Z-poxy last fall that I've had since at least 2010 on 6 guitars with no problems.

So I borrowed some space heaters and raised the temperature in my shop from in the low 60s to around 75 degrees last weekend. I ran some tests with my year-old batch of z-poxy and it worked fine. Trying to use it below 70 degrees was definitely the problem before. Then mother nature decided to lend a helping hand by providing four days in a row of temperatures in the 80s! It got up 89 on Monday. In Seattle, in April! The z-poxy has loved it all week. It's ready for level sanding and moving on.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter