Epoxy

[Smitty]

(Quote) As far as the bond of resorcinols being mechanical that is true and that is a property also shared by urea and epoxy gluesl. Resourcinol glue is a 2 part chemical mix like epoxy and the urea glue (like Weldwood plastic resin) is a water based product and all have chemical reactions ot set the internal glue structure. (end quote)




Right, but what I was trying to say is that my understanding (of the article I read about it, and I may very well have misunderstood and got this wrong) was that resorcinol bonded chemically to the wood, as well as mechanically, which if true would set it apart from the other glues. In any case, I'm going to go have a look at your link, and thanks much.

[ZUL8TR]

chemical bond

(Quote) As far as the bond of resorcinols being mechanical that is true and that is a property also shared by urea and epoxy gluesl. Resourcinol glue is a 2 part chemical mix like epoxy and the urea glue (like Weldwood plastic resin) is a water based product and all have chemical reactions ot set the internal glue structure. (end quote)




Right, but what I was trying to say is that my understanding (of the article I read about it, and I may very well have misunderstood and got this wrong) was that resorcinol bonded chemically to the wood, as well as mechanically, which if true would set it apart from the other glues. In any case, I'm going to go have a look at your link, and thanks much.

I understand your point and my own opinion is that there is only a mechanical bond to the wood and the chemical bond occurs in the glue as it sets. Perhaps because of the penetration of the glue into the wood pores the chemical bond in the glue is also in the wood because it is below the 2 surfaces being glued? Could you find the article you are referencing and post it?

After you read the link I provided I would be interested in your thoughts. The article is Appendix C to a classic book on wood boat construction by Larry Pardey. Here is a link to the book on google review (time limited link I believe) it opens up at Appendix C and has better Figures than the link I originally provided.

http://books.google.com/books?id=zSH...age&q=&f=false

[Smitty]

I haven't read the linked article yet because it wouldn't download; I'll try again on the library's computer in a day or two. The article with the statement about the unusual nature of the resorcinol bond to wood, was published easily twenty years ago in a Woodenboat article about a professional builder, I think. I might still have it, but could hardly find it in time to contribute to this discussion.

[Mark Monkres]

I like Smiths Penatrating Epoxy sealer first then Smith laminating resin. I have met Chris Smith look him up. intersting product

[Wagneracing06]

Pet syringes for small batch mixes

I use System 3, Have for years as does Darrell Sorensen.
Not that anything is wrong with West. It is excellent. Just when I used West I had a lot of waste as the mix ratio is like 4 or 5 to 1. Just very hard to make a small batch of less than one ounce.
System 3 is in Auburn Washington. I use the the basic epoxy at a 2 to 1 mix. They have 3 hardeners Slow, Medium and Fast. For me where I live the temp varies from low 30s in winter to over 100 in summer as slow to to slow and fast is way to fast. The Medium works best for me at those temp ranges
I have been told that their T-88 is excellent. However, I broke down and bought a Sticky Stuff pump and it is set up for 2 to 1. That pump has paid for itself many times over by reducing waste.
There has been many threads on this subject in the past and there will be many who say that the product they use is the best. I prefer System 3 because I like it and know how to work with it so that is what I use.
Visit their web site. Has lots of info on epoxy.

I've found that the small syringes that I was given to orally inject medicine for my dog work out really well for small batches. These can be bought in most chain pet stores. I just use the recommended ratios from the West System ratios corresponding to the cc measurement on the tube of the syringe.

Rick Wagner Sr.

[ZUL8TR]

epoxy

I haven't read the linked article yet because it wouldn't download; I'll try again on the library's computer in a day or two. The article with the statement about the unusual nature of the resorcinol bond to wood, was published easily twenty years ago in a Woodenboat article about a professional builder, I think. I might still have it, but could hardly find it in time to contribute to this discussion.

When you find it just pass it on or PM me to continue. As far as the Appendix C link I sent you if not able to open it is a web site that does not require a download so I can't figure what is the issue you are having.

[Smitty]

(The second link worked) Well now THAT is an eye-opening and sobering discussion!! I have been reading Larry Pardey's articles and at least one book since he started writing in the Seventies; a smart guy who does first-class work according to a friend of mine who knows him. I'm going to get this book for sure.

The loss of strength with temperature could be an issue for a raceboat sitting out on hot sunny days, if painted in a dark color, maybe. I remember Burt Rutan, when he was designing homebuilt plastic airplanes saying that no plastic airplane, even when built with autoclaved parts, should be painted any color but white. That's far from a closely-related situation to our boats in any respect (just for starters, Rutan's resin was vinylester, not epoxy), but I wonder how hot the glue-joint around the deck could get on a hot day under black paint. And the fatigue life of the stuff doesn't look impressive either. Interesting that the failures Pardey finds are in the glue, not the wood fibers. Boy oh boy. I have to read that again (when my battery is recharge).

Thank you very much for that link!