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Ok, I'm trying out Zpoxy and it sure doesn't seem to be going as smoothly as Todd's Tutorial. When I squeegee it there are streaks left from the squeegee or credit card as I tried that too. The zpoxy doesn't seem to flow level.
I tried it last night too and ended up sanding it back to the wood because of the same reason of the streaks.
When I squeegee it on I think I'm seeing the litle bubbles that Todd talks about but they don't really seem to disappear as I continue to squeege in a chevon pattern and then go long ways at the end to squeegee off the excess or what I think is excess.
One reason I like closeups on videos. Maybe I'm putting it on too thick and not pressing enough? What do you think I'm doing wrong here?

Chris
I always, always get streaks in the Zpoxy like you. I just sand it back to the wood using 400 or 320 grit.
If the pores are filled I may leave it bare wood or I may use the 50/50 zpoxy/Alcohol and wipe on with a rag.
I'd also like to know how others get a 'smooth' finish with no streaks!!
Mat

Hey Chris,
I get similar results. Did you try to thin the Zpoxy with some alcohol? That is what helps me to get a more consistent flow on the guitar.

Mat,
So you are using the same method as Hesh then. Just press and fill the pores with a credit card and squeegee off most of the excess and what streaks or left then sand off or level? Pretty simular to using a oil base pore filled?

Chris,
I thought about giving that a try but wanted to see what suggestions I would get from the zpoxy users first .

I can put a short youtube of it up if anyone thinks that would be of any help? It's just a pan of the top.

Yes I am. Got all my knowlegde about Zpoxy from Hesh's tut and Todd's videos...

Does it look as if it's too thick of a coat?

Chris, sand it back and try a single edge razor blade. It's one of Michael Payne's tips and it made a huge difference when I tried it. You'll probably still get some ridges, but light sanding should easily remove them. The wipe on a 50:50 coat to even it out. That should give you a nice surface to top coat. One warning, I've used it on 10 guitars and had pores show up a 6-8 weeks after applying Tru oil or lacquer tops coats. I know of at least one other guy who has had similar results.

Bob

No help on getting it smooth, but do be sure to wear a respirator and wash your clothes after sanding that stuff. I hear epoxy has a nasty reaction if you become sensitized to it.

There is also what appears to be a lot of little bubbles that almost looks like dust on the surface. Is that common or is that also a sign it needs to be thinned that 10-15% because there wasn't really much flow out to speak of and I weighed the amounts of the mix. Is there a shelf life to Zpoxy?

Chris-
When epoxy cures, it releases heat. This can expand air trapped under the epoxy and cause bubbles to appear on the surface. One 'trick' is to warm the surface before adding the epoxy, and then let it cool down after application. This can be as simple as getting the shop quite warm before you start, then dropping the room temp once the epoxy is applied.
Folks who make cedar-strip canoes and kayaks are familiar with this- it can look like hundreds of little balloons on the surface the next day!

I haven't used Zpoxy, but WEST and the other boatbuilding epoxies have basically indefinite shelf life, though the hardener may change color a bit. So I don't think you need to worry about that very much.

You asked about the surface appearance and amount of epoxy showing? Pictures are difficult to interpret and you were trying (correctly) to show the surface reflections, but it seems to me that you have a bit more epoxy on the surface than I would leave. It takes very little epoxy to do a guitar back- a tablespoon or two is usually more than enough- and I end up taking most of it off with the squeegee. BTW, avoid the temptation to re-use the 'squeegeed' epoxy on the guitar as it generally has a lot of entrapped air. (Keep a mold or jig handy that could use a little 'waterproofing' or 'mistake hiding' and use the epoxy on that....)
Edit- the advice about multiple applications is 'spot on'! as well.
Cheers
John
PS- thanks for your many useful videos and postings here and on YouTube!

It almost seems like it might have been faster to just break out the pumice and 2# cut of shellac. That's what I did on the last one. Then a FP for a thin seal coat of shellac. Less sanding, less toxic and less spraying. Remind me what the advantage of this epoxy is?
Well, it really does to seem to pop the figure. I didn't realize there was that much fiddle back on it.
Thanks for the tips all.

Chris I have found that the streaks and high spots scrape out easy then I sand. I buy the cheap box cutter blades at the Dollar store to scrape with. The 1st coat for me gets mostly removed to wood, I thin the second coat a little to get it to flow out better, then I apply the wash coats real thin with a cloth wad like doing French polish.

The 1st guitar was a little frustrating but the next 3 I have done went smoother. I left too much epoxy on the surface at first, now I only mix about 1/2 as much as I did at first and still get good coverage, so less is better but you have to work more spreading it with the squeegee. The shower squeegees like Tod uses seem to work great making a little epoxy go a long way.

Fred

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Fred Tellier
http://www.fetellierguitars.com
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Chris buddy I just have to ask if you are using Z-Poxy "finishing resin" and not Z-Poxy epoxy glue which comes in a number of varieties too? The finishing resin has the proper viscosity to pore fill as per my toot, System III "finishing resin" works great too and West Systems 105/205 epoxy glue also works great viscosity wise too. I'm sure other epoxies work too I just have no direct experience with them so I can't comment.

I use probably less than a teaspoon to do an entire back. The trick is to squeegee off as much excess as possible and then the sanding is easier AND you have less chance of pulling the filler out of the pores when sanding if you are not sanding very much....

Personally I found that the major source of confusion for a couple of folks that I showed this to in person was the term squeegee... The term squeegee being also a verb implies if not specifies that we use a squeegee like motion with the goal being to remove the excess. My own experience is that what we really want to do is mash the epoxy into the pores from every direction finishing up at approx. 45ish degrees to the grain direction. I only use the credit type card to "squeegee" off the excess after attacking a specific area using the card to mash the epoxy downward from all directions.

With this method I have yet to not get a complete fill in 2 coats and I am sanding back to the wood too with either a block or a ROS and it's staying in the pores. This was much faster and easier than pumice and I did try that as part of the Robbie O'Brien french polish course out of Red Rocks Community College that I took.

Lots of ways to do lots of things as you know but my preference is to sand the epoxy back to the wood. I want finish on my guitars not epoxy but I will settle for some stinkin epoxy in the pores.... If you want to use the final coat of epoxy as a wetting agent to get that wet look and even out the color if you did not completely sand back to the wood that's fine and covered well in a couple of places.

Good luck - I hope this helps.

I like to sand back to wood after z-poxy pore filling. I tried thinning it out with alcohol and wiping a thin coat on after sanding back to wood. But beware-If you do this and later sand thru your laquer or whatever you are spraying after pore filling, you will get a light spot on your wood. That is why I always sand back to wood with z-poxy before spraying. The tempting part of using z-poxy is how great it pops the grain in the wood before spraying. But a good finish will do just as well, you just won't see it until you are almost done and ready for buffing.
My 3 cents.
John

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John Nowicki

Hesh,
Yes my friend it's the finishing resin. And I read your tut too. I mixed up about a 1/4 oz. or 8 grams and did the whole back and sides with it.
Good point about the sand through at a later date or repair. That just might make me sand back to the wood. I wanted a bit of an amber tint to warm up the walnut and was thinking that the zpoxy would do that. But so would seedlac and shellac that I plan on using for the FP seal coat.
I guess a lot of you may be wondering what I'm talking about when I say FP seal coat. What I've been doing or what I did on my last build was to use Robbie's method of FP (I have the DVD)to do what I call a quick FP. As it does put a quick seal and FP on the guitar. I only do 2 sessons and that is what I use for my seal coat as I can use the shellac as a toner of sorts and build enough finish for a shiny seal coat. I don't get any runs and have to sand them out and I don't put too heavy of a seal coat of shellac on like I usually seem to do when I spray shellac on and I really don't enjoy sanding and cleaning the gun after spraying and I don't have a spray booth so that is a problem in itself. Hopefully by the time I spray this one with Nitro I'll have one .
Well it's been long enough for it to have cured and I went to Lowes and bought a furnace filter for the box fan so maybe I'll sand it back and give it another go and see what happens. Or maybe wait till tomorrow and sleep on it

Chris,

I sort of skimmed the previous posts, so forgive me if I repeat. Your idea of applying FP coats after Z-Poxy sounds solid to me. I used to get pores re-appearing after a few months, but now I apply several coats of shellac on top of the Z-Poxy. That seem to seal better than Z alone.

Also, I'm putting the Z on in VERY thin coats, and smoothing out all of the ridges with a gloved finger. That stuff is hard to sand if it's applied too thick. It's taken me 4-5 coats at timesd to get to where I like, but I still think that thin coats are easier to work than having to sand off excess.

Hope this helps,
Ken

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Ken Mitchell
Durham, NC

I sanded it back to what appears to be almost the wood and the sides look pretty good and the back doesn't look to bad at all. I think I'll put one coat on tomorrow and thin it some . I think the pores will all be filled after this next coat.

Chris,
I just finished a guitar for the 5th time, and used zpoxy on all of them. This one had Koa as back and sides. I used to used the old credit card way to squeegee off, but got sick of that as it took too long. Now, I just apply with the credit card and smash into the pores as much as I can while working small areas. Then after the all the areas are filled, I take one of those thick blue paper towels and just wipe the zpoxy off so there are no ridges at all. Try to remove as much as you possibly can. Then I sand back to bare wood. It's okay to have splotch marks at this time if you don't get it all off. I've done 2 coats in a day before and had no problems with it drying in time. The key was to wipe off as much as you could. This way you could get 4 coats on in 2 days. The back only needed 2 coats and then a wash coat of 50/50 poxy/alcohol. The sides I needed 4 coats, then a wipe of 50/50.

Also, for the zpoxy, there is a shelf life from what I found. I tried doing a guitar last year and the zpoxy would just not harden. I then bought a new bottle from LMI, and it hardened in about 6 hours. My bottle was about 3 years old, so I'm sure there is a shelf life. I'd give it about 2 years from my experience.

Also, when I mix the epoxy, I use one of those little plastic measuring cups that you can buy bulk from lee valley. I always add a touch more of the hardener. I think this helps with the finish drying faster. Hope that helps.
Tracy

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Tracy
http://www.luthiersuppliers.com

I used Zpoxy for the first time a few months ago. I warmed it up in hot water before mixing. It flowed thin and smooth, and squeegeed off easily. Filled the pores great, and sanded to wood easy. I'm sold on warming it first.

Bob

Hear hear! I have become overly sensitive to Zpoxy sanding dust this past year. I always think "Bah, this little bit won't bother me" and sure enough, within an hour I'm wishing I would've donned the respirator.

I dont know for zpoxy becouse I use epoxy from this co.( http://www.r-g.de ) and in their manual writte:

"Adding more hardener than specified does not result in faster curing, but poor properties. Likewise the processing time cannot be extended when less hardener is added. On greater deviations the mixture may fail to cure!"

Fric

I can't help you with your technique. I've never used Z-poxy. When I use West Systems I sand it all the way back to the wood.

Re, reaction to cured epoxy. I've gotten a rash from sanding epoxy before. I've found it doesn't happen if I let it cure long enough. I'd suggest a minimum of 24 hours, but 36-48 is better. Always were breathing protection when sanding.

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I didn't mean to say it, but I meant what I said.
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Now THAT is golden advice. I will add that you should not wear the same dusty cloths from the last session to finish the sanding job, fresh clobber every session and you should keep a fan blowing the fumes away from you at all times during mixing, and application. It is also worth considering that some epoxy products have less toxic hardeners than Zpoxy. I believe that West Systems, a long time player in the epoxy game, actively formulate 'some' of their products to reduce exposure for the user to what can be the absolutely devastating effects of epoxy contact dermatitis.

I guess one needs to ask themselves if they are in this for the long term and then make an informed decision about which epoxy product is best suited to them. But be careful, I can tell you first hand that this is real nasty stuff your fooling with. You may also wish to google "Epoxy Amine Blush" before you decide that epoxy laid under a finish is worth the trouble. There is no doubt it can be, and there are many examples where it has worked really well. But be warned, should the environment not work in your favour during application, particularly when using anything with natural driers such as any of the oils or varnishes as a finish, then it can be a heartbreak you just won't discover until a few weeks after you have polished out that beautiful finish and it begins to soften and go tacky on you.

Do your research because all finishing methods have their pros and cons.

Cheers

Kim

I guess everyone has their own ideas to what is the key to making this work. From my experience on my last guitar, I have decided the key was to really pay attention to getting rid of any ridges to minimize the amount of sanding required between coats. Notice how careful Todd is about this in his videos. I was going batty introducing new pores each time I sanded but things got better once I smoothed out more during application and sanded less during leveling.

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.

I use West and squeegee it, then let it sit for maybe a half hour and sort of French Polish it with an alcohol-soaked rag to get rid of the high spots. Still requires sanding and usually 2 applications on walnut.

There just really isn't any fun way to pore fill is there?