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Hi all, first time poster here. I am spraying Target coatings Emtech 6000 finish on my 11th guitar, a sinker redwood/black walnut 00 and noticed white streaks in the grain lines only on the ebony bindings. The redwood top and walnut back and sides look great and have no problems. The body was pore filled with Z-poxy and sealed with 2 coats of shellac. I called Target Coatings and talked to Jeff who said that there has been some problems with this finish over ebony. He did not have a solution and suggested I ask other builders for advise. This is the second guitar I have finished with this product and would like to continue to use it if I can find a solution.
Thanks,
John

John:

Did you fill the bindings with the body? I suspect the pore fill should be done with a dark filler on the ebony binding. I made the mistake of waxing an ebony fretboard with regular paste wax. The light contrast in the grain just looks bad. That was a relatively easy fix. Yours will be more work unless someone has a quick fix approach.

Danny R. Little

Danny may be on the right track. When you say "I called Target Coatings and talked to Jeff who said that there has been some problems with this finish over ebony." sounds like no sealer (z-poxy or whatever) on the ebony. (If properly sealed, should reacte like any other wood). Just guessing, but I know if acrylic lacquer fills a volume (or is too thick), it looks milky. Maybe what you're seeing BUT I've also heard it will clear over time, so maybe leave it a weak or two. Let us know what exactly you did & how it pans out.
Anybody else having trouble over sealed ebony??

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Dave
Milton, ON

Thanks guys for the replys and advise. I did take the Z-poxy over the bindings and sealed the body with two coats of shellac but maybe when I sanded the epoxy smooth I pulled some of the filler out on the bindings . This is the third guitar I have used ebony bindings. The other two were maple and myrtle bodys and I didn't pore fill either. I used nitro on both and had no problems. I am doing some tests filling the grain lines on some scrap binding so I will let you know if that's the answer.
Thanks,
John

I've got one with walnut box and ebony bindings - sealed with 2 coats of shellac then on to the EM 6000. No problems. I just finished redoing a neck and did the neck and sides of a new ebony fretboard with the EM 6000. No sealer coat on the ebony and also no problems.

Sorry I don't have any suggestions but I'll be real interested to find out what is causing that if you can figure it out.

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Steve Smith
"Music is what feelings sound like"

John,

Does your ebony have mineral deposits in it? Maybe nitro has a way of dissolving these deposits where a water based finish won't. I have sprayed EM6000 on several ebony headplates without issue. But they were streak free before I started.

Ken

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What do the white streaks look like. Ebony will often have some streaking, if it isn't dyed. I suspect the streaking in these fingerboards would really come out under finish. Do the streaks look similar to this? It may have nothing to do with the finish.

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Looking at this problem today with fresh eyes it looks to me like an adhesion problem, like the finish is just bridging the grain line gaps and not filling them. The binding is pretty consistently black with no mineral deposits that I can see. Also the top bindings are from a different source than the bottom one's yet the problem is showing up on both. Yesterday I filled the grain on a scrap piece of the same binding and will spray it today so hopefully that will take care of the problem.
John

Yikes
I'd send that shot to Jeff, along with your finish schedule. This needs resolving!

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Dave
Milton, ON

That white stuff is sanded EM6000 material getting into the pores. Its even a bigger problem if you wet sand with water. Mineral spirits is better. I have finally come to the conclusion that your surface needs to be perfectly filled before using em6000. You must not spray over that stuff. I have rubbed affected areas with water to good effect.

Mike

Mike, I am coming to the same conclusion that every pore, gap, nook and cranny needs to be filled before spraying the Emtech. I sprayed the finish over a two day period and did not sand in between coats so I don't think sanding dust in the pores is the problem. Keep in mind that only the ebony surfaces were affected and not the walnut, redwood or zircote. The question is why the ebony is the only wood with the problem? I just did a test on some scrap binding where I pore filled with medium viscosity super glue, sanded the surface smooth, sealed with two coats of shellac and sprayed four coats of Emtech with much better results. I will strip the bindings on the guitar and give it another try. If it doesn't work this time I guess I'll be going back to nitro.
Thanks for all the help,
John

Just a couple mor thoughts

That could be the problem.... with Ultima, I always used Gerald Sheppards schedule of spray 3 coats / wait 3 days. Gives it time to properly dry between sessions.There were often gaps/pores that needed drop fill, which i did between sessions, but they never stayed milky.

If everything was sealed the same, it should react the same. Maybe you can just see it more readily on the ebony.

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Dave
Milton, ON

Thanks Dave, I also thought that the darker wood may show up the problem more readily so I donned the headband magnifiers and had a better look. Upon very close examination of the black walnut back and sides, peruvian walnut neck, sinker redwood top and zircote headplates it appears that the only wood that was affected was the ebony.
Cure time is also something I have considered. Maybe the ebony being harder and denser needs more time to fully cure.
John

Thanks Dave, I also thought that the darker wood may show up the problem more readily so I donned the headband magnifiers and had a better look. Upon very close examination of the black walnut back and sides, peruvian walnut neck, sinker redwood top and zircote headplates it appears that the only wood that was affected was the ebony.
Cure time is also something I have considered. Maybe the ebony being harder and denser needs more time to fully cure.
John

I think with ebony, its way easier to see the white stuff. Whatever you do, do not wet sand with water. Another recent thread talked about using mineral spirits. I tried that and it worked great.

Here is the problem (I think). Any pore will cause the finish to build a "caldera" around the pore. The more you spray, the bigger the caldera. Then when you sand, some of that dust will get stuck in there. Especially if you wet sand with water. Now, although the finish will melt into previous layers, it will not melt the dust. Very dissapointing! We still need to figure out how to remove that dust (and it is hard to do). Because no matter how well you pore fill, you are always going to miss a few. I am still working on ideas for this. So, thats about it for now.

Mike

Mike, yeah, I know what your saying about the dust in the pores issue and it being more visible on the dark ebony but I used some zircote on the headstock, rosette and endgraft that had some areas that are as dark as the ebony with no problems . In the picture I had not done any sanding of the finish yet and in researching this finish I knew not to use water as a sanding lubricant. I have finished ten other guitars, nine with nitro and one with Emtech. I was just getting a handle on the nitro with guitar #9 going very smoothly but I was real concerned with the toxicity issues so after helping a friend finish two guitars with the Emtech I decided to make the switch on guitar #10, a cuban mahogany/adirondack 0M sunburst. It took several tries to get the sunburst to look right but it came out pretty nice and had no issues with white spots in the grain although I did not use ebony on this guitar.
I am running some tests on some scrap ebony bindings now and I will let you know what works best.
John

Yeah, there's got to be something else going on IMO.
This is macassar ebony, no sealer & lots of pores etc., with 3 coats em6000 brushed on (ie heavy coats) 1hr apart (no sanding). No white in the voids (a few light reflections from the pores in the shot). If you have a couple of pieces of the SAME binding, I'd suggest seal/fill one as you did on the guitar, then paint both as above & see what happens.
Nice guitar BTW John.

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Dave
Milton, ON

IMHO, its all about the base material, and how well it takes pore filling. Also, maybe darker woods are harder to see if pore filling was sucessful? None the less, the darker the wood, the more noticable the white stuff. Seriously, get the pores filled, avoid water sanding, its gotta come out right. One suggestion might be to avoid "too" many layers between leveling. And if any white stuff shows up, work like the dickens to get rid of it before anymore coats. It will not melt.

Mike

This is an interesting problem to be sure. I just refinished a walnut neck that had to be rebuilt which included a new ebony fretboard. When it was time to refinish I had about a 3/8" stripe of fresh walnut next to the fretboard. I recalled a thread where someone had noted it is easy to fill pores with Emtech 6000 just by spraying more coats. So I decided to just put on finish. I brushed on 12 coats over 3 days, 4 coats a day; 2 coats in the AM separated by at least 30 min then 2 more coats in the evening. The finish was straight out of the gallon can. After the last coats I let it sit for a week then leveled and polished with no problems.

This stuff seems to be pretty forgiving to me which makes your problem even more perplexing. I want to suspect filler or other base coats or contamination but I'm sure you've already looked at all this.

_________________
Steve Smith
"Music is what feelings sound like"

Dave, do you have any ebony to do a test with?
Mike, have you used the Emtech on a guitar with ebony appointments and if so what was your result?
I've been experimenting on scrap pieces of the ebony binding the last couple of days and it seems to work if I totally fill all the pores so that the surface is level and smooth then seal and topcoat. What makes this really perplexing is that even though I tried sampling this finish on five other species of wood only the ebony had the problem. I didn't bother to pore fill these samples and still didn't have the problem even on some Zircote that had some grain that was jet black.
John

[quote="jfitz"] I've been experimenting on scrap pieces of the ebony binding the last couple of days and it seems to work if I totally fill all the pores ..../quote]
No idea what you mean. If pores not "totally filled" they show white??
You need to recreate the problem, them back out 'till it goes away. If you're not sanding, then bridging dust into the pores as Mike suggests, gotta be contamination or something in the seal/fill. Doubt it's the base ebony....this is raw gaboon with 2 heavy coats... no white.
Anyway, I'm outta suggestions...good luck

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Dave
Milton, ON

OK. The white stuff is finish dust. It will not melt when you apply further coats. Why? I do not know. It only happens when there are pores (not properly filled) or scrapes. This is one good reason to avoid level sanding with anything less than 320, and even 320 can be too much. Wet sanding with water makes it even worse. To top it all off, the darker the wood, the more you will notice it.

Why not seen with nitro? Probably nitro dust dissolves easily AND it does not turn into a high contrast color powder when sanding.

Upshot: Epoxy fill. Level. Epoxy fill again, level. Epoxy wash (thinned), then level. Finally, repair remaining pores with CA. Then move on to shellac (for color tone) then emtech. If you see "calderas" form after emtech, you missed some pores. Sand it down and repair. And do not use water when sanding. If at anytime you see white stuff locked in pores or scratches, do something to get rid of it. Do not spray over it. Although EmTech 6000 is water based, it is not completely soluable in water once cured (in that it will not immediately dissolve solids on exposure to water or new coats). It is an emulsion suspended in water. Its just more complicated than that.

This product is a good and forgiving finish. But that does not mean one gets to use it without knowing and working around it's pitfalls. Go back to nitro, build an explosion proof vent system, and deal with 4-6 week cure times. Everything has it's drawbacks.

Mike

Thanks everyone for the advice. I talked to Jeff at Target coatings again and he suggested that using dark trans tint dye on the bindings after pore filling might help color any residual dust or anything else in the pores that might turn white after topcoating. This is exactly the type of tip I was looking for. Thanks Jeff!!
I tried it on some of the test ebony binding srcaps that had turned white in the pores and it seemed to work well. I will try it on the guitar and let you all know if it works .
Thanks,
JF

Hmmm. So Jeff is aware of this. What about if it happens on the sides? (and it does).

Mike