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I have used Smith's all wood epoxy for several years and have had good luck with it. It is somewhat forgiving of errors in mix ratio( a calibrated eyeball is all I have ever used). And I have never had it fail. I have not noticed it mentioned very often here on the OLF as most members seem to prefer the West System.

I am about to the point of reordering and am wondering if it is time to switch? Is there a compelling reason that the West System is used more often than the Smith's? Anyone with experience with both? Inquiring minds want to know.

Cecil

Cecil it depends on what you are using it for.

We often talk about System III, Z-Poxy, and West but in the context of using them as pore fillers. SIII and ZP are finishing resins and not intended to be glues. Both companies make epoxy glue too but many of us use the finishing resin for pore filling.

Smiths is good stuff and I used it for years on RC airplanes and helicopters but again as a glue and not as a pore filler.

West Systems seems to excel at being a glue and a pore filler with some of the pro finishers also using West for pore filling.

I doubt that this helps you very much but I will say that when I used Smiths I thought that it did not sand as well as any of the 3 mentioned above.

There are many different epoxies and formulations. Most companies offer serveral types for different things. West Sytem, System 3, Mass, Hexel, Smith etc. are companies that offer a wide range of expoies with different qualities. For general work your Smith's is fine. I am assuming the Smith's you are using is a one to one mix. If so you are right about it being forgiving in the mix. The type most people think of when they think of West System is a 3 to 1 mix. I have used 5 to 1 mix types. In general the epoxies with higher ratios are stronger but have problems with a thing called blush. This is a another whole topic in itself. The typical offerenings from these companys are for laminating and wetting out fiberglass cloth. The have a fairly low viscosity and penitrate well. This would also lend them to pore filling. There are many additives you can use to modify the epoxy to make it thicker or stronger, or to sand better, etc. You can do the same with your Smith's and Smith's makes different types as well. They have a laminating epoxy and other types for certain uses. Check out all the different offerings for Smiths if that is the company you like.
A general tip for gluing wood with epoxy is don't clamp any more than enough to bring both pieces together. It is easy to starve a joint with too much clamping pressure when using epoxy. The thing to do is to wet out both surfaces to be joined and then mix a thickener in the remaining epoxy and apply that to the joint. This will insure you won't stave the joint.
Another thing that is interesting with epoxy and a little conterintuitive is that the more hardener you add the softer the finished product is. Of course you always want to mix it to the right ratio but you might keep this in mind when you are "just eye balling it". Don't think that if you err on the side of more hardener it will be harder !
Link

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

Link my friend that is about the best epoxy post I have ever read! Nice going!

Thanks Hesh,
I have built and repaired a lot of boats. There is a lot more to be talked about with epoxies but for guitar use not really needed. One more thing I will add is for a thickener a quick and easy one is wood flour. They sell it but most of use have a ready supply in the little bags that hang off our ROS sanders. Only add additives to epoxy you have already mixed well. For filling holes and thickening I keep plastic containers of different color wood dust to use with the epoxy. I use three basic colors. Maple for light, something for medium and some dark stuff. You can also add colorant to mix.
Link

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

Thanks Link,

I'm with Hesh, an excellent post. I will be sticking with the Smith's. I use it as a general adhesive where water in unwanted. I can do without the exact measuring required for West Systems. I also use Z-poxy for filrer.

Cecil

So So true I have always suspected that most every complaint about Zpoxy not hardening was due to adding too much hardner. Like my friend Hesh, I too am a RC hobiest and flight trainer at my local RC club. I often go to many well experianced RC modeler's shops to help with building and covering aircraft. I can tell you, almost with out fail, when you look at a hobiests epoxy bottles there will be far less part B (hardner) left in the bottel than there is part A (base). Everyone assuems that it is better to over mix hardner than base. In fact with in a narrow 2%-3% range just to opposite is true.