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Would like to switch over from using a water based glue/plus inserts for neck joint to epoxy . Your recommendations please .Read that somogyi in his book suggests west system. Have used system 3 in the past from woodcraft for other glueing jobs. When I checked on amazon, there was a myriad of suppliers for z poxy,was not sure which one to get it from , as so many had lousy ratings . your thoughts please . Also noticed that the thinner zpoxy can be used for pore filling , have never tried it . Have used water based , and oil based fillers. I guess one can thin the thicker zpoxy with acetone or alcohol to use as a pore filler

Zpoxy won't work for gluing, only pore filling. And it works very well for pore filling without any dilution. Some do a final wipe with diluted Zpoxy (50% alcohol or so) after pore filling.

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"Building guitars looks hard, but it's actually much harder than it looks." Tom Buck

Umm, let me understand the purpose. What kind of neck joint are you using, and what are you going to? Why are you changing the approach you're using?

Given ernie's response below, this post deleted as largely irrelevant.

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Aaron Craig

Zpoxy comes in multiple forms: 5 minute dual syringe w/resin and hardener, 5 minute bottles, 30 minute bottles and the Finishing resin bottles. 30 minute should be a stronger bond than 5 minute for regular gluing needs. The Finishing Resin is the grain filler.

Their products are reputed (I have no experience with the regular Zpoxy products, just the finishing resin) to be less fussy than West Systems and System III wrt precise measuring of resin and hardener. I bought my Finishing resin at a local Hobbytown which which carries their products.

http://www.supergluecorp.com/zap-brand-products/z-poxy-line

The West Systems 105 hardner with the 207 clear hardner will be the best best for gluing joints. The clear aspect of the 207 hardner is great but the main reason I'd pick it is that the cure cycle is long enough to allow you plenty of time to join your parts and still have it fully cure by the next day.

You can also use the 105 resin and 207 hardner for pore filling but Zpoxy may offer two advantages in this regard.

1. Zpoxy (finishing resin) is not a "toughened" resin. Toughened resins are formulated to resist microcracks and are generally used for structural applications. Toughened resins are more difficult to sand as a result. Zpoxy is eaisier to sand than West Systems 105...which probably is toughened (though I couldn't confirm this to be the case).

2. Zpoxy can be thinned with denatured alcohol without changing the mechanical properties of the material much, which offers a great latitude when using it in a finishing or pore filling capacity. Once again, without knowing for certain that West Systems 105 is a "toughened" resin (I believe it is), I can't say for sure but trying to thin the West Systems mixtures with alcohol could greatly reduce its overall strength when cured.

Not to mislead but I use a boutique resin that I have pails of left over from a former business. This is a toughened resin that I expect has mechanical properties that well exceed West Systems 105 but there won't be any worries for me switching over to the 105 resin system when I run out of it 20 years from now. When I use epoxy for pore filling...I use Zpoxy finishing resin.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

thanks for the explanation stu. It basically coincides with the info I was looking for.I want to use an epoxy to strengthen either dovetail or butt glued uke joint. Though I noticed that bogdanovich uses system 3 epoxy with a silica filler for filling rosewood and behlens oil based mahog, for filling the neck. Can one use the silica with the zpoxy? or is it a waste of time??.I have used oil and water based to fill pores . I don/t care for the water base stuff too much. I would like to try pore filling a rosewood OM with the zpoxy. I will go ahead and get some west system. Our closest marine dealer is 47 mi away,so will order online. Thanks everyone and keep on sending those replies , so can evaluate which epoxy is more suitable for each application.

I don't see any real benefit to using a super-strong epoxy for a dovetail neck joint. I haven't read Somogyi's books yet, and if he uses epoxy for such a joint I'm sure he has some valid reason for doing so. But Tightbond, LMI white, or hide will all hold a well fitted dovetail very well for decades, while at the same time making repairs in the future, such as neck resets, much more pleasurable than trying to detach an epoxy glued dovetail. I do know that Somogyi seems to be the camp (seemingly a small camp) that believes neck resets are not inevitable, though he admits to having done resets on a few (3 or so) of his necks for various reasons. So, if you believe your design is such that a neck reset will never be necessary, who really care's about the ease of doing so in the future. I'm not that confident. Maybe one day I will be, but right now, I find it hard to believe that sometime, maybe after I'm dead and gone, even the greatest guitar I'll ever build won't need a reset.

I have yet to build a uke, but the nature of the string forces at issue there makes the repairability issue less of a worry.

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Aaron Craig

Thanks for the input aaron . That/s why I/m doing the research now . Each of the various epoxies has their strengths and weaknesses.I glued a cocobolo FB to a cherry neck with a alphiatic resin white glue and got a nice hump on the fingerboard. It was butt glued. The hump was right over the butt glued joint. Did not use fasteners. It was a PITA to remove fingerboard. Told myself to use epoxy next time. Just called west system their closest dealer is 48 mi away in lawrence. The cost of their measuring cups /resin/harderner is over $65. For a cheapskate like me it is hard to justify spending that kind of $ to do 1 or 2 epoxy joints per month. System 3 might be more doable , as it can double as a finishing resin with the addition of a silica thickener ,or use the resin and hardener to glue the occassional joint. PS I am just now reading the SOMOGYI books.

I'm with Aaron on this one. LMI white or Titebond ought to be plenty strong for this joint. Epoxy's permanent. Miserable to remove.

If you've got issues with a dovetail on a uke, I'd work on the joint itself. Personally, I find the dovetail to be a devilishly difficult joint, and I use a bolt-on Mortise &Tenon joint - which requires no glue at all. Lots of good posts here on the joint. I love it - can do neck resets and adjustments very easily.

In regards to West Systems, I've been using the 105 resin & 205 "fast" hardener for various non lutherie tasks. It's a great product, assuming you want an epoxy. Much better than the stuff they sell at home centers in tubes.

In my experience,the 205 has plenty of working time, at least 20 minutes as long as the ambient temperature is not too hot and you don't mix a large batch in a small container which concentrates the heat causing it to cure faster.

Mix it in a container that's large enough so that after it's mixed & waiting to be used, it won't be deeper than 1/16".

They also sell 105/205 in pre-measured packets which simplifies mixing the 5 to 1 ratio.

Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

Todd what does DA mean ?? alcohol , acetone??/ I/ve thinned system 3 before using denatured alcohol. So am guessing it/s what you meant.

He means Denatured Alcohol, Ernie.

And (anyone) if you actually CAN thin West System 105 with DA I'd like to know. I certainly can't thin the epoxy I use now...it's basically ruined with the addition of DA.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic