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This message is about a new way to apply Z-poxy for pore filling a guitar. I hope it isn't pre-mature because I literally just tried it 10 minutes ago and have only applied one coat of the Z-poxy. So I don't even know how things are going to look when it's cured. However, it worked so well, I couldn't wait to share.

I was researching Z-poxy ideas and on an R/C planes forum a fellow was saying how excess Z-poxy could be removed just after application up by heating the surface with a hair dryer and brushing it with a paint brush. The Z-poxy would get runny from the heat and the excess would go up into the brush. That got me thinking. So after I applied Z-poxy with a spatula on the back of a guitar I'm currently pore filling, I warmed the surface with a hair dryer and started brushing it. This worked well at smoothing out ridge lines well except for the brush hairs that came off and went on to the surface. So then I switched to a foam brush and it still worked well. In fact, it worked great. The Z-poxy on the surface got quite runny and I was able to smooth it out to the point of no visible ridges at all. From there I went on to the sides, where I hadn't applied any Z-poxy. First I spread some out with a spatula, then I went back over it holding the hair dryer to the area I was working, keeping both the surface and the foam brush warm. I found that the Z-poxy was starting to spread out like paint. From there I went to just putting a blob of Z-poxy in the next area I wanted to work and held the hair dryer in place while I spread it out with the foam brush. At first I thought starting with a blob was a mistake because it didn't seem to spread very far. In fact, a lot of it went into the foam brush. But the great thing was that it came out again, just like paint off a brush! I could go to an area with no Z-poxy and, keeping things warm, I could paint the surface just with the Z-poxy coming off the foam brush. This was so much easier and faster than spreading it around with a spatula and it ends up going on very thin and smooth - no ridge lines!

The other great thing about this was the bindings. I always have found that getting the Z-poxy nicely onto the rounded over part of bindings to be problematic. I used to end up going around the edge of the guitar with my finger. But when "painting" it on that wasn't necessary. With the foam brush and heat, the Z-poxy just painted on to the rounded binding just like any other part.

I haven't tried it yet but I think the best is yet to come i.e. the neck. Always a challenge with a regular spreader and I always end up using my fingers way too much. Looking forward to applying Z-poxy on the neck with a hair dryer and a foam brush.

Give it a try!

Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

Pat: Wonder if you noticed and air bubbles coming from any of the pores....?
Tom

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A person who has never made a mistake has never made anything!!!

I do this with Z-Poxy every time I've used it. I've suggested using a hair dryer/heat gun on low a couple of times with no responses so I figured no one tried it or no one wanted to. It really does make working with Z-Poxy so much easier.

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Doesn't this cause problems as epoxy cures much faster with heat. I've had a whole pot go off in a few minutes just leaving it in the sun on a hot day.

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"I am always doing that which I cannot do, in order that I may learn how to do it."
Pablo Picasso

https://www.facebook.com/FenskeGuitars

No.

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Yeah, it just works way better after it's been warmed. As Pat suggests, give it a try

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Thank You and Best To All

From a technical standpoint I would say if this method is working for people there is nothing wrong with it. Yes, epoxy will cure more rapidly when heated but the actual temperature it reaches will have the greatest effect on making it kick over more quickly. To a point, viscosity will also decrease with heating as well and this would be much more of an art than a science. Truth be told, even room temperature 5-minute epoxy is actually designed to cure at elevated temperatures... Typically, in the 180°F to 200°F range in order to fully react. What is actually taking place is that any polymer chains that have failed to react are given a chance to stretch out and wiggle around, thus finding other end groups to react with and more completely polymerizing. The composites industry cures everything at specific temperatures for varying lengths of time. Therefore, the controlled use of low heat to improve handling properties is absolutely acceptable.

Heating ZPoxy may indeed speed the process slightly but there's no downside that I've discovered and I've never had it 'go off' on me from heating it. I don't know what would happen if you got it REALLY hot but if you heat just enough to get it flowing it behaves much better than the sticky goo that a colder batch creates.

Another benefit is that when heated it really penetrates and can give a deeper look to the filled wood. If it gets too thin/warm it will not fill as well as a cooler, thicker batch but a couple of coats still works great for filling pores.

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Thank You and Best To All

I applied Z-poxy to the neck of my guitar this afternoon using the hair dryer and foam brush and indeed find it far easier than any other spreading device I've tried. And I didn't have to use my fingers anywhere. I guess I don't have the touch, but I can't do a ridge-free smooth out with my fingers. I also find that I can't apply Z-poxy as thin with my fingers as I can with, say, a spatula.

I didn't notice any bubbles as I heated, but I take your point, Todd, about heating the surface first. I don't know if reduced cure time is an issue - I'm not heating the epoxy for very much time - just during the application. With respect to thickness, I think I'm getting a thinner coating with this method than when using a squeegee. As I said, it's like paint. I guess I don't have a good touch with a squeegee either because I always leave small ridges or streaks. And trying to get rid of the ridges or streaks drives me nuts because I end up sanding through. So, in fact, I was thinking my order might be to do first applications with a squeegee or spatula, and last application with the heat and foam brush with the hopes that I would have little sanding to do after the brushing and thereby avoid the sanding through.

Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

...or you could just use WEST (105 with 207 hardener).

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

I have found that thinning it a bit with denatured alcohol makes it easier to apply a smooth coating.

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wah
Wah-wah-wah-wah
Wah

Last night I used a gloved finger to coat the entire back a drop or two at a time to prevent the ridges/valleys I invariably get on the last thin coat with a squeegee.

If you had posted this tip before yesterday I would have given it a try, smile.

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Formerly known as Adaboy.......

I'm liking the sound of this Pat. I'm going to give it a try on my next pore fill

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Joe Beaver
Maker of Sawdust

shhhhhh Trevor. Don't let this secret out.

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jw ( o)===:::

I am interested in using WEST as I can't easily find zpoxy where I live. Is west pretty much the same for all intents and purposes?

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Doug

Don't let fear or common sense stop you from trying to build something

I LOVE West Epoxies but mixing very small batches is too complex for my simple guitar needs.

Mixing ZPoxy 1:1 is easy, fast, simple and cheap. If I was building a boat I'd use West Systems but no need IMO for such a simple task as pore filling a guitar.

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For all intents and purpose - yes. Just check the system you are buying. Some work best with special pumps and special ratios (other than 1:1) to perform properly and make sure you get the correct hardener for your purposes. 207 is mentioned above to go along with 105 epoxy. If you don't get it right they can take a longer amount of time to harden, if they harden at all enough for level sanding.

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What is so complex about 3:1 mixing ratio?

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jw ( o)===:::

I use two small plastic bottles to make mixing small amounts of West systems epoxy easier and mix by weight using a inexpensive scale in grams, I write the mixing weights needed on one of the bottles for various amounts i.e Part A to B 10 grams to 4.4 , 5 grams to 2.2 , 3 grams to 1.32 ,and 1.5 grams to .66 , that way I can just mix what I need ....

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MK5acoustics.com

Nothing at all but how do you get there? By weight and "an inexpensive gram scale?" Or volume? Do you measure 3 grams to one gram of hardener with a scale? Or 3 oz. to 1 oz of hardener. None of it is, on its face complex, but for me personally it's way too much effort for a product that isn't adding any strength and you can simply squeeze out two equal length lines, mix and off you go. To each their own of course but all I need in my shop is another tool or scale to measure epoxy when a very good to excellent alternative is readily at hand with no additional tools needed.

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I'm not sure how each of us define complex but... I prefer things a bit simpler.

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Some context that gives a little more information: In my original post I mentioned that I was "researching" Z-poxy. The reason I was doing that was because I was trying to find a process for getting that last coat. I needed some way of getting on a thin ridge and streak free coat to even up the colour of the wood for those areas where I sanded through. I had tried thinning the epoxy with alcohol and applying it with a lint free cloth, but I found that the thinned epoxy did not impart the same hue to the wood as the un-thinned epoxy. On top of that, the thinned epoxy didn't seem to go on with any less streaking than the un-thinned expoxy. So, for me, that didn't help. The heated epoxy does result in a uniform colouring of the wood, so in that regard, I feel this method is useful for putting on a last coat to get a uniform hue to your wood. I note Todd's concern that brushing can result in a thick coating but I'm finding that the epoxy gets so runny when warmed up that it is going on very thin.

On a related note, I have tried the sanding back to wood method but have always found this results in more open pores. So I've given up on that and now always aim to have a very thin, continuous, flat coating of Z-poxy.

Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

Larry, I can see how you would consider it complex and I agree, using a scale to mix small quantities is not only complex with West System, it's a major pain in the a............back side.

I use 3cc glass syringes (that have each cc broken into fifths) to mix my West System. The most I mix at any given time is just over 2cc so I have small containers with wide mouth lids that I can lower the syringe into, draw up the epoxy and hardener and mix away. I tried the scale version early on and quickly abandoned that.

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jw ( o)===:::

I have tried both Z-poxy and system 3 and each has some issues so after reading Trevor's post and Joe's reply in quote above, I picked up the West 105/207 to use on my Ziricote builds. Since I already have an accurate digital scale mixing will not be an issue. I will do some testing over the next few days as I get the bodies ready for finish.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

I tried a System 3 product, can't remember which one, that took a long time to get hard enough to sand. There was, and is, no doubt about its strength and it did eventually get hard enough to sand but the 'Finishing' resins seem to get harder, faster than the laminating resins.

As most people speak of ZPoxy in the forum I'm not sure everyone is using the same "Finishing" ZPoxy that cures faster, harder (perhaps not stronger) than their 30 minute laminating resin, which I tried and wasn't happy with the cure time or hardness.

I haven't used West 105/207 so I'm interested in what you discover Fred.

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