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Epoxy Pore Filling
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Author:  Hesh [ Sun Jan 04, 2009 9:53 am ]
Post subject:  Epoxy Pore Filling
Epoxy "finishing resins" and some epoxies do a very nice job of filling pores. Here is how I use Z-Poxy to fill pores. This same method also works very well with West Systems 105/205 epoxy and System III "finishing resins."

As always be safe. Epoxy is a sensitizer and some folks do have allergic reactions to it. When working with epoxy protect your skin, have ventilation, and a respirator is not a bad idea either.

Z-Poxy is available as a "finishing resin" product that is not the same as the Z-Poxy glue offerings. This holds true for System III as well. Be sure to use the finishing resin variety of these products and not the epoxy glues. The primary difference is the viscosity where the finishing resins tend to be thinner and easier to work into pores.

For our test piece, since we have to look at it for a while, let's use Brazilian Rosewood. On this particular piece the pores are pretty nasty.......

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It looks like we have our work cut out for us with these pores.....

Z-Poxy is a very easy to use product and the mix ratio is 1:1.

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Again be sure to use the "finishing resin" variety of Z-Poxy.

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I use latex gloves to keep the Z-Poxy off my skin.

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One of the benefits of using Z-Poxy is that the mix ratio at 1:1 is not critical. In my experience with System III the mix ratio is critical and they recommend that you use a gram scale to mix the two parts. Even though we are using Z-Poxy I like to use a gram scale anyway just to be sure.

For this demonstration I only need to mix up about 1 gram of Z-poxy for each of the two applications that I plan to do.

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Due to a limitation on how many pictures can be loaded with each post this thread will be continued........ Thanks!
Author:  Hesh [ Sun Jan 04, 2009 10:03 am ]
Post subject:  Re: Epoxy Pore Filling
The BRW has been sanded first with 120 and then with 220. I used my ROS because it is fast, dust free, and does not seem to leave any scratches.

Once the BRW has been sanded and wiped clean of any dust the epoxy is applied. I like to work an approximately 6" X 6" area at once and then move on to another area.

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I use a credit card type card as an applicator. This same card will later be used as a squeegee. When I was learning to pore fill with epoxy and other pore fillers the mistake that I made was using the card as a squeegee. Instead use the card to "mash" the epoxy downward into the pores. Do this from all directions with particular attention paid to 45 degrees to the grain of the wood.

Only after you have mashed the epoxy as best that you can into all of the pores in your working area then use the card as a squeegee to remove the excess epoxy from the surface of the wood. I usually dump my excess epoxy on the next area that I will be working.

Since you are removing the excess epoxy this filler goes a very long way and one package of Z-Poxy is probably enough to pore fill 4-5 guitars.

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Here we see the epoxy being mashed into the pores from all directions.

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And here is what our test piece looks like after one application of epoxy.

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Typically it takes me two coats of Z-Poxy to fill the pores but your mileage may vary. The pore filling goes very fast and if it takes several or more coats to fill your pores just stay with it, observe full cure times, and also note the idea of mashing the epoxy into the pores as opposed to squeegeeing it off when the pores are not filled.

For clean up I use rubbing alcohol which also works very well on a lint free cloth to remove any build-up that you get around the bindings and edges of the guitar. Just smooth these areas out with the alcohol dampened cloth.

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Let's let our test piece cure now - Z-Poxy recommends a 6 hour cure time and longer is better.

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In the photo above the shiny streaks are the pores, not all the way filled yet but with epoxy building in the pores and reflecting the light.

To be continued....
Author:  Hesh [ Sun Jan 04, 2009 10:38 am ]
Post subject:  Re: Epoxy Pore Filling
Now that our test piece has cured we are ready to level sand it and apply the second coat of epoxy.

For level sanding epoxy I like to use foam blocks that I cut out of this foam that LMI offers. It is very dense, not unlike this toot author...., and also conforms to curves well when you need it too.

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3M gold 240 paper works very well for this.

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At this stage we are trying to build up the epoxy in the pores of the wood. So, with this objective in mind all we want to do is lightly sand the test piece just enough to take down any ridges that we have left from the application process. I sand in the direction of the grain.

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Now with our test piece lightly sanded we are ready to apply coat 2 of the epoxy.

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Again a very little amount of epoxy goes a very long way.

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And again we are using the card to mash the epoxy into the pores and once the entire area is filled we use the card as a squeegee to remove the excess.

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Our second coat is now applied and needs to cure.

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To be continued....
Author:  Hesh [ Sun Jan 04, 2009 10:58 am ]
Post subject:  Re: Epoxy Pore Filling
With the second coat now cured it's time to level sand again and check to see if our pores are completely filled. The same sanding process is once again used.

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There are two schools of thought when using epoxy as a pore filler. Some folks like to leave a thin epoxy film on the entire surface of the wood for it's beauty and wetting properties. Other folks like to sand the epoxy back to the wood leaving it only in the pores.

Both methods work well so I am going to show you both of them.

I have sanded the epoxy off the surface and leveled the surface as well. In this picture the epoxy is only in the pores and the pores are completely filled.

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For the folks who want to leave a thin film of epoxy on the surface of the wood just sand back less and don't be concerned about sanding through the epoxy in places - it's bound to happen and easy to fix.

The fix for sanding through so that you can even out the color of the wood is to mix up a small batch of Z-Poxy and mix this with a 50:50 mix of denatured alcohol. This "thinned" epoxy mixture is then wiped onto the entire surface of the wood with a lint free rag.

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Once the thinned epoxy is wiped onto the test piece you can see that the color has been evened out and you can also see how well epoxy pops figure and wets the wood.

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Our test piece is now completely filled. Remember what the wood looked like before we started?

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Additional notes:

The wood should be well sanded, free from scratches and dust. Do not apply a coat of shellac or any sealer prior to pore filling with epoxy. Shellac can be applied directly to cured epoxy but epoxy does not stick well if shellac has been applied to the wood first.

Necks - What works very well for me when pore filling necks is to paint the epoxy on with a finger in a latex glove. Again try to press the epoxy into the pores and then use your finger to squeegee the excess off. Clean-up with a lint free cloth dampened with rubbing or denatured alcohol. The gloved finger method usually results in a completely filled neck after only one application.

Most importantly - get comfortable, get a piece of scrap, and do a trial run. You will quickly learn what works best for you and hopefully find the process enjoyable.

Thanks for looking! :)
Author:  Alain Desforges [ Sun Jan 04, 2009 11:09 am ]
Post subject:  Re: Epoxy Pore Filling
Right on! Great photography too, my good man... Thanks for the info!

Could you take another close-up picture and then compare them side by side, pores vs. poreless???
Author:  Fred Tellier [ Sun Jan 04, 2009 2:17 pm ]
Post subject:  Re: Epoxy Pore Filling
Great job on this tutorial Hesh, I am thinking of trying this on my cocobolo OM but am wondering if this is safe to use under nitro lacquer, and is so what is uses between the epoxy and the lacquer. I use Behlan brand vinyl sealer and nitro.

As for the gloves you use, I have been told the latex will not properly protect you from epoxy, Nitrile is supposed to be better. Sometime if we meet again I have a great funny story about one of my problems with epoxy, that needs to be told in person.

Fred
Author:  Hesh [ Sun Jan 04, 2009 2:40 pm ]
Post subject:  Re: Epoxy Pore Filling
Thanks guys! :)

Al - sure, here you go. I tried to isolate the same areas which was tough but I think that I got close. Here it is sanded back to the wood. BTW I used the ROS for this and the epoxy stayed in the pores.

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Fred I knew that someone was going to say that about the Nitrile gloves and I knew that but was out of them..... :oops: :D Good catch and good tip for this thread.

You will have to tell me the story at the next gathering! :D
Author:  Alain Desforges [ Sun Jan 04, 2009 3:20 pm ]
Post subject:  Re: Epoxy Pore Filling
That is awesome! Thanks for the pic, my friend. Great results!
Author:  SniderMike [ Mon Jan 05, 2009 1:26 am ]
Post subject:  Re: Epoxy Pore Filling
Hesh, you need some Beano. Great toot!
Author:  cphanna [ Mon Jan 05, 2009 7:48 pm ]
Post subject:  Re: Epoxy Pore Filling
Hesh, thanks for posting this tutorial. I've been reading about this method for as long as I've been coming here--but this is the first time I've seen it demonstrated. I've never tried it, but I probably will do so sooner or later.
Patrick
Author:  Jim Watts [ Tue Jan 06, 2009 12:43 am ]
Post subject:  Re: Epoxy Pore Filling
Hesh, Great job man [clap]

Fred - I've used epoxy (z-poxy and others) as filler on nitro finished instruments with great success. I use the Mcfadden vinyl seal and lacquer, but can't imagine that the Bhelen stuff is all that different.
Author:  Fred Tellier [ Tue Jan 06, 2009 1:36 pm ]
Post subject:  Re: Epoxy Pore Filling
Thanks Jim, its good to know it has worked with nitro, I will try it on my next finish. I have used Z poxy in my model airplane adventures in the past and know it works well as a grain filler.

Fred
Author:  Parser [ Fri Jan 23, 2009 9:08 am ]
Post subject:  Re: Epoxy Pore Filling
Great Tutorial, thanks Hesh!
Author:  Hesh [ Sun Jan 25, 2009 9:14 am ]
Post subject:  Re: Epoxy Pore Filling
You are very welcome guys! [:Y:] :)
Author:  Steve Sollod [ Mon Jan 26, 2009 1:35 pm ]
Post subject:  Re: Epoxy Pore Filling
Thanks Hesh!

To measure out the z-poxy I've gone to the drug store and bought some syringes. Sometimes they will even give them to you. Also, what makes a great mixing cup are the ketchup cups in fast food resturaunts. I'll pick up a couple when I go.

I take off the needles and hold the syringe with my gloved finger covering the hole and measure a small quantity. Then let it drain into the cup (push out the residual) and put an equal amout of the other part in from another syringe. Mix with a popsicle stick and you're good to go...
Author:  Darryl Young [ Thu Feb 26, 2009 9:44 pm ]
Post subject:  Re: Epoxy Pore Filling
Hesh, this is an awesome tut!!! [clap] [clap] [clap] [clap] [clap]

I sure needed to see this as I have little experience filling wood pores.

A question, I've seen where folks have used epoxy as a finish on furniture and it is nice and tough. I realize it is heavy in it's natural state, but why couldn't epoxy be used as a guitar finish if thinned sufficiently? Sounds like the z-poxy is thinner than regular epoxy and it could be thinned 4:1 or 8:1 or whatever is required to achieve the desired thickness. When I built radio controlled airplanes we used thinned epoxy to fuelproof the firewalls on the model planes. I just guessd on the ratios but regular epoxy was thinned roughly 8-10:1 when I used it for that purpose.
Author:  Hesh [ Fri Feb 27, 2009 6:53 am ]
Post subject:  Re: Epoxy Pore Filling
Thanks guys! :) Please also keep your tips and methods for using epoxy as a pore filling coming so that this thread can be a great source of info for folks.

Darryl my friend I am chuckling because I think that many of us have had it occur to us after applying epoxy that it looks good enough to be a finish. The problem is that epoxy is a little soft to be a finish and you will discover this if you apply it to a test piece, wait a month, and then try to buff out the test piece. The epoxy will start to come off...... wow7-eyes :D

But it's fine under a real finish and even better if you sand back to the pores although you don't have to and you can leave an epoxy film on the surface of the wood under a more durable finish.

A couple of years ago IIRC JJ looked into this and may have done some tests too so he would be a good one to ask what his experience was testing epoxy as a finish.
Author:  Michael Dale Payne [ Fri Feb 27, 2009 12:12 pm ]
Post subject:  Re: Epoxy Pore Filling
The best part about this tut is that Hesh points out that sanding back to the wood does not mean there are no glossy spots left but that the vast majority of the glossy spots are the pores
Author:  Chris Paulick [ Sat Mar 14, 2009 11:47 pm ]
Post subject:  Re: Epoxy Pore Filling
Thanks Hesh. [:Y:] [:Y:] [:Y:]
Author:  Gregg C [ Sun Mar 22, 2009 12:23 pm ]
Post subject:  Re: Epoxy Pore Filling
Hesh,
When I sand the Z-Poxy it sands with little balls or small rollers, is this normal ??
I measured each part wiht a digital scale so I'm sure the mix is good, I let it cure for 18 to 20 hours.
Any ideas or is this normal ??
Gregg
Author:  JJ Donohue [ Sun Mar 22, 2009 2:14 pm ]
Post subject:  Re: Epoxy Pore Filling
I've used enough Zpoxy to know that this is not normal. After 12-24 hours it sands into fine dust. You may have either bad product, a contaminated surface which prevents the material from properly curing or you may have just laid it on too thick and the heat of sanding is causing buildup, assuming you had the proper mix in the first place.

On the "Using Zpoxy as a Finish" topic...a few years ago, I actually tried it on the back and sides of an IRW guitar. I waited a month before wet sanding and buffing out. It polished to an acceptable sheen and looked great from afar. The only problem was that it was too soft and scratched easily. It adhered tenaciously to the surface as evidenced by how difficult it was to return it to a bare surface!
Author:  Gregg C [ Sun Mar 22, 2009 2:26 pm ]
Post subject:  Re: Epoxy Pore Filling
I'm sure my mix is correct. However I did put it on a bit thick. Thanks.
Author:  Jojobilou [ Sun Mar 22, 2009 4:38 pm ]
Post subject:  Re: Epoxy Pore Filling
Thanks fot the tuto and the great pics... [:Y:]

I used z-poxy fot my second guitar, with black walnut and burl smooth-leaved Elm... with a KTM9 brush finish...

Works great and easy to apply for a beginner like me... [:Y:]
Author:  DGr33n [ Mon Apr 13, 2009 3:12 am ]
Post subject:  Re: Epoxy Pore Filling
Thank you very much for sharing, I look forward to learning here at OLF
Author:  ayavner [ Tue Jun 16, 2009 8:51 am ]
Post subject:  Re: Epoxy Pore Filling
Hope its not bad form to resurrect an older thread. What is the general idea about pore filling or sealing on the top? Every tutorial I have seen shows it being done on the back, and I think its implied that you don't do the top, but I have yet to see it explicitly mentioned one way or the other.

Thoughts?
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