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I’m going to have some time the next couple of weeks and want to post some more videos. I was wondering if I could get some recommendations?
Thanks
NssthanThere is a YouTube channel. If you look at Natural Stone Systems TV there are 14 different videos there.
The following link is to the channel and a list of the videos
I would suggest learning proper techniques before you make videos to show people how to do something. Rodding with polyester is not the right way to do it. It needs to be encapsulated in epoxy, not poly, not acrylic.
I posted this information on my YouTube site as well. Having the exact numbers helps.
Both polyester and vinyl ester resins are prone to water degradation
due to the presence of hydrolysable ester groups in their molecular
structures. As a result, a thin polyester laminate can be expected to
retain only 65% of its inter-laminar shear strength after immersion
over period of one year, whereas an epoxy laminate immersed for
the same period will retain around 90%.
When you have the exact numbers it makes it a little easier to decide what adhesive is appropriate. Under the sink isn’t submerged so I’m sure for our application the results would be much better.
Good point and worth evaluation.
than
I posted the study information on the youtube video. at
I found this just to support why not acrylic. It is the only one of the 3 that becomes malleable when heated. Perhaps not likely in a sink, but more plausible in the stove.
Q: Is there a difference between polyester, acrylic and epoxy resins?
A: Acrylic resin (but not acrylic emulsion, which is the basis of acrylic paint) is a thermoplastic, which means it is one of a group of plastics which can be heated and manipulated repeatedly, whereas polyester resin and epoxy are thermosetting plastics, which use heat or a catalyst to solidfy into a solid mass that won’t melt down. Acrylic is mixed from acrylic polymer, a dry powder, a methyl methacrylate monomer, a thin liquid, and usually an organic peroxide hardener of some sort. If pieces of any size are contemplated, an autoclave or hydraulic press is necessary for reducing air-bubbles and counteracting the internal stresses created by the strongly exothermic reaction. The dust is toxic, as is the monomer and its vapors. And the organic peroxides are especially poisonous, some of them being explosive and others causing instant blindness if they get in ones eyes.Polyester resin, a syrupy clear liquid, is mixed with a small but variable amount of a strong catalyst, which causes the curing mass to heat up (and to craze if you’ve added too much.) It is versatile stuff, being useful for coating, casting, and building up composites, usually in conjunction with fiberglass cloth. It is not as hard or as clear as acrylic, having a somewhat yellowish tinge to it. And it- and especially the catalyst- is also highly toxic, and is persistantly evil-smelling as well.
Epoxy resin works similarly, doesn’t smell as bad, but it -and the hardener that makes it set- is a sensitizer, meaning that you can get a nasty allergic reaction after repeated exposure. Some hardeners are not as bad as others in this respect. Epoxy won’t set water-clear like acrylic, and doesn’t resist sunlight (UV) degradation as well, but works better with high-tech cloths, like Kevlar and graphite.
Hope this help some,
Than
I am not trying to change the topic. I still would like some ideas. Since it has been mentioned a couple of times about not using polyester for rodding and I don’t think anyone could say that the science supports that. I would submit that maybe it was the perfect storm of carelessness/ignorance. Whatever the adhesive, maybe the channel was cut then rod inserted knife grade floated over the top.
Theory 2. If they used polyester flowing and mixed it incorrectly (too hot) in a channel that wasn’t big enough to allow the rod to have much adhesive on the sides. The glue could have shrunk and cracked allowing moisture in.I will admit that since epoxy doesn’t shrink as much a poly it is more idiot proof, but I am a firm believer that the best/easiest way to idiot proof any process is to get rid of the idiot.Thanps any video suggestions:)I was wondering if you have any videos on cleaning and sealing existing granite. We often get asked to show the customer how to clean the granite to prepare if for resealing.
You’re kidding right? It is a commonly know fact that polyester does not hold out in wet conditions or when exposed to UV light for prolonged periods of time. It contracts, when it contracts it allows moisture to penetrate. Granted if you’re using stainless steel you’re far better off than plain flat steel rod.
I am not against polyester, we use poly for laminations and miters for interior work, but rodding is different. You’re adding another variable.
I am not trying to get into a lengthy debate. do what you want, I just though it would be appropriate to use correct methods when making videos. things are about to change, standards will change, tolerances will change. Requirements will be tighter soon, and believe me they wont allow poly for this type of work.
Just because everyone thinks it’s true doesn’t make it true. In the study the tell us that epoxy is the one that is not uv stable. And as far as shrinkage goes epoxy shrinks about 2% where polyester shrinks about 7%.
They both shrink. One is less than the other
I still think my 2 theories are worth considering.
How often do people see this? I have been working in a granite shop for more than 20 years. Half of those years in shops with more than 15 employees and I have never seen this.
Cameron, I appreciate your feedback. I just think that in our industry we have more opinion than science.
Than
so youre telling me polyester resin is UV stable?
I am not a fabricator, I am a stone refinisher. I see everything after the fact. I dont need to be a chemist or scientist to tell you that without a doubt, poly is not UV stable at all, or moisture stable. Epoxy is far less vulnerable to the elements.
in most cases, because I am told by the homeowner, they wont call the original company that did the work back to look at the damage for fear of more problems. not that the blame is automatically on the fabricator, but thats how they feel. if no one is calling you back to look, then of course you’ve never seen it in 15 years.
Im not implying your work is failing, its just an example.
there are different variations of polyester resin, so when you do your research make sure its stone specific. surfboards use poly, as far as Im aware and they are used in direct sunlight.
Hello Than I applaud your efforts in making videos. Just watched the one on rodding. good job. The countertop industry is always stronger when we share ideas. The more ideas the better.Ploy or Resin. Is poly cheaper than resin?
Poly IS resin. this is the problem, you are unaware, watch Than’s video, go rod with poly and possibly have an issue. I am not coming down on you for not knowing, education is key, however education doesnt mean anything if the information is incorrect.
Than, I am not saying you can never rod with poly and that all rodded tops with poly will fail, but the potential is there. Why not use expoxy and be done with it? Granted someone can still screw it up with epoxy
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