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Paste epoxy strength
Posted by:
Michael Danek
(---.alma.mi.frontiernet.net)
Date: November 30, 2020 11:23AM
I keep seeing posts on this and other forums about the strengths of paste epoxies, usually stating that the shorter the cure time the lower the strength. Does anyone have actual data supporting this trend? Would be nice to hear from some epoxy suppliers or those who have done rigorous tests. Opinions are sometimes valid, but often not. Re: Paste epoxy strength
Posted by:
Billy Vivona
(---.nycmny.fios.verizon.net)
Date: November 30, 2020 11:44AM
results: all epoxies are strong enough for fishing rods Re: Paste epoxy strength
Posted by:
Tom Kirkman
(Moderator)
Date: November 30, 2020 11:51AM
Cure time has little to do with adhesive strength. We've covered this in several RodMaker articles written by the people who make the epoxies.
Conversely, it is easily possible to use the wrong epoxy for the task at hand, in which case you may have a failure, but it's not due to the epoxy not being strong enough. Typically either the liquid or gel consistency epoxies will work best for the rod building chores we're faced with. An epoxy paste, such as PC-7, however, not because it's not strong, but because the clearances we work with (should be working with) in joining rod building components typically are not large enough to allow such an epoxy to properly wet out and fill the mating surfaces. Worry less about epoxy strength and more about the right product for the job. ........... Re: Paste epoxy strength
Posted by:
Herb Ladenheim
(---.68.237.121.hwccustomers.com)
Date: November 30, 2020 12:00PM
YES!!
Hint: Wet the inside of the seat as well as the arbor. Herb Re: Paste epoxy strength
Posted by:
John DeMartini
(---)
Date: November 30, 2020 12:09PM
I can not think of any component of a fishing rod that can generate enough force to fail a epoxy bond. The primary cause of adhesive failure is poor surface preparation, mixing errors and not allowing the adhesive to properly cure also other reasons involving human error.
Generally when adhesives are properly applied the substrate fails before the bond line. So feel safe in using any brand name adhesive. Re: Paste epoxy strength
Posted by:
Herb Ladenheim
(---.68.237.121.hwccustomers.com)
Date: November 30, 2020 01:25PM
One way to negatively affect a bond is if you clean-up with too much solvent that will wick into the joint.
Herb Re: Paste epoxy strength
Posted by:
Mark Talmo
(---)
Date: November 30, 2020 02:32PM
Michael,
I have nothing to add as Billy, Tom, Herb and John have said it all and I agree. Mark Talmo FISHING IS NOT AN ESCAPE FROM LIFE BUT RATHER A DEEPER IMMERSION INTO IT!!! BUILDING YOUR OWN SIMPLY ENHANCES THE EXPERIENCE. Re: Paste epoxy strength
Posted by:
roger wilson
(---)
Date: November 30, 2020 07:25PM
I will add this comment, based on prior experience.
I have worked with about every cure time epoxy on the market over the years doing a myriad of tasks. I have found one factor to be universally true with respect to epoxy cure rate. i.e. the brittle factor. For example, a very slow drying epoxy glue that takes an hour or two to cure, tends to be somewhat flexible, as measured in the gluing world. But, as the cure time of the epoxy goes down, the flexibility measure on the glue goes down, the brittleness factor on the glue goes up. i.e. If you take a couple of pieces of steel that have been glued together with epoxies of various cure rates - all of the strength of the epoxies is quite similar. However, with respect to impact strength - i.e the glued objects being hit with a sledge hammer, the longer cured epoxy, will tend to stay glued together under heavier and heavier blows with the hammer. Conversely, due to the more brittle nature of the quicker gluing epoxy, the 2-5 minute cure epoxy will tend to fracture and break more easily than the more slowly curing epoxy. i.e. The two glues have comparable strength. But, the epoxy joint of the faster curing epoxy will tend to fracture more easily than the more slowly curing epoxies. How does this information translate to the world of rod building? The information is largely irrelevant .i.e. in the Rod Building world, the typical components on a rod will break before any of the epoxy joints fail or fracture. But,is there a difference in the glues with different cure rates? Yes, there is a difference. Does the glue character difference affect joints in the rod building world? Normally, never. Be safe Re: Paste epoxy strength
Posted by:
Tom Kirkman
(Moderator)
Date: November 30, 2020 08:58PM
Roger,
That is chemically incorrect. As Ralph O'Quinn pointed out in one of his many excellent articles for the magazine, cure time has nothing to do with epoxy strength or "brittleness." What often happens, according to Ralph, is that many of the "quick cure" epoxies developed for the home hardware market are formulated from poor components. Cheap components, if you want to use that word. They tend to fail more often than the better and more expensive epoxies which are normally found in the slower cure, more expensive products. The problem is not the cure time, but the cheap formula components of the quick cure stuff. Trondak's Quick Bond sets in just 10% of the time it takes the company's regular Rod Bond to set. But they are equal in strength. Neither is more brittle than the other. The same can be said for any other brand of quality epoxies, whether they set in 20 minutes or 20 hours. Having said that, you are correct that many quick-set epoxies are less strong and more brittle than longer curing epoxies, but it's not the set and cure time that makes the difference - it's the quality of the components that make up the epoxy. ................. Re: Paste epoxy strength
Posted by:
Lance Schreckenbach
(---.lightspeed.hstntx.sbcglobal.net)
Date: November 30, 2020 09:08PM
I use the paste epoxy that is used for reel seat bond to the blank and arbors on all kinds of stuff. I have had it on my washing machine to fix a nob mount on the control panel, that gets turned on a daily basis. It has held for at least 5 years and it sets in 15 minutes. What Roger is saying is mostly a fact, the faster a resin sets the more brittle it is. The chemistry of an epoxy can also be changed to make a fast setting / curing epoxy to have more elasticity, so that is not always the case in special circumstances. Re: Paste epoxy strength
Posted by:
Michael Danek
(---.alma.mi.frontiernet.net)
Date: December 01, 2020 09:19AM
Thanks, Tom and Ralph O'Quinn. Sorry, only registered users may post in this forum.
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