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I wet-sanded to 12,000 Micromesh then buffed with Menzerna Fine & Extra Fine. Feel free to comment.

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JJ
Napa, CA
http://www.DonohueGuitars.com

Very well done JJ. Nice high gloss and classy box

Very nice -
Id like to see some close ups --
The Rosette, bindings etc --

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Lance@LuthiersForum.com

What is the equivalent to 12,000 micro? I am planning on sanding up to 4,000 grit silicon carbide and using the same buffing compounds. How fast where you spinning your wheels?

Butt Wedge




Rosette

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JJ
Napa, CA
http://www.DonohueGuitars.com

Looks super JJ. Very nice work indeed.

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The Zootman
1109 Military Rd.
Kenmore, NY 14217
(716) 874-1498

Looks great JJ. Glad to hear the 9000 worked for you. I am planning to use it myself in the near future.

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Don Atwood
Arlington, VA

Colby...I don't know that there is an equivalent standard grit to 12,000 Micro-mesh. I went through 2,000 grit conventional and then 4,000, 6,000, 8,000 and 12,000 MM. All I know is that the 12,000 MM feels like soft leather and really burnishes it to a high luster.

I used two 14" buffs per side at 1100 RPM.

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JJ
Napa, CA
http://www.DonohueGuitars.com

Looks real good! Nice shape, too; graceful!

Don...While the finish is shiny and clear it's not possible to see the flaws that I can't seem to buff out.

It doesn't quite make it as a true mirror finish. I'm not sure how to describe it, but there are randomly scattered sections where it appears to be slightly diffractive as opposed to being totally reflective. I actually noticed this as I was wet sanding. It almost looked like water was trapped deep in the finish. After allowing it to hang for 10 days while I was traveling I was hoping that if it was water, that it would dissipate by the time I returned. Well, it didn't, and as buffing out did somewhat improve the look, it's still there to some extent.

On the other hand, the neck was wet-sanded last night after the finish was sprayed on 3 weeks ago. After finishing the wet sanding, I immediately started to buff and it has a more homogeneous-looking finish. However, it's not as shiny! Assuming that the surface may be too soft, I plan to re-buff the neck in a week or two.

I'm totally working by the seat-of-my pants but taking notes and trying different things to find out how to tame this animal.

So, if I had to specify a schedule for the next trial it would be:
...Spray
...Level sand and finish sand after 3 weeks
...Buff out after 1-2 weeks

Any comments or suggestions would certainly be appreciated.   

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JJ
Napa, CA
http://www.DonohueGuitars.com

Hopefully the 9000 pro, Mario, will chime in here.

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Don Atwood
Arlington, VA

He's only taken a small bite so far...but I hope the more detail I posted will help to set the hook!

As I progressed through the buffing, I kept asking myself..."What would Mario do?"

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JJ
Napa, CA
http://www.DonohueGuitars.com

"What would Mario do?"

MArio would do exactly what you are doing and keep trying stuff and take notes <bg>

Honestly, one of my pet peeves with ALL waterbornes is that what works wonderfully one time may not work so well the next. It is a fussy creature, but we need to remember that we are asking a lot of it, too.

Sometimes I need to go to a wet compound, like Meguiar's #10 or 17 by hand, quite vigorously, yet sometimes it is dead on glassy with the Menzerna.

For the areas that don't look as good on the body, if you have a magnifier of sorts, take a close look under good light, and tell me what the surface looks like. If the surface looks as smooth as the rest of the body, then we have something happening in between coats causing a refraction effect, or we may even have something at the sealer.
If the surface doesn't look as smooth, then try to work it some more at the buffer, being super careful not to overheat the area. IO say this because when we buff an entire back, for example, we have a large area to cover, and heat isn't a problem, but when we are "spot buffing", we can quickly forget we are working a tiny area and work it too much. Been there, done that!

So, go forth, take looksee, and we'll work it out.

From my limited experience with 9K I looked at the buffed surface under a magnifier and the surface was pourous unlike nitro which is glass smooth from the burnishing effect of buffing. 9K will get shiny and smooth but as Mario pointed out, we just can't compare it to nitro as it's an entirely different animal. I believe the surface porosity is the culpret of refracted light instead of reflective light.

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tim...
http://www.mcknightguitars.com

Tim, that would only make sense if the entire body was dull, but we have dull areas.

I've not seen this porous surface that you mention, either. Sounds like the 'micro bubble' problem that some folks report with various waterbornes, and it surely has to do with the user, possibly because of a thinner or even something used to clean the gun.

I just looked at the surface under magnification. I think you're both right. Here's what I see:

The entire surface is micro-pebbly (new term). And it seems to appear as Tim describes as porous. While it is smooth to the touch it almost looks like it could use additional buffing.

In the areas that are "blotchy" (perhaps as Mario describes) it almost looks like a wet surface that has been wiped and the dried water leaves a blotchy film. Except that it isn't a surface film...it's within the matrix of the finish. And it is non-uniform in location and severity. This is the more disturbing feature. Is it possible that the layers that were laid down are not adhering in certain areas?

As far as possible contamination, I used it straight out of the can after stirring with a clean tongue depressor. I used warm water to clean the disassembled components of the gun. The top was prepped with shellac sealer and the sides and back were filled with Z-poxy, leveled and sanded prior to shooting the 9000. I see the effect on both woods.

I'm goung to try using the Meguires on the surface to get rid of the micro-pebbles but I am not optimistic about getting rid of the blotchiness.

As both of you have stated, it's not Nitro. It actually looks clear and shiny from a normal distance but it is disappointing in closer inspection. Unfortunately, I'm not able to get it to show up in a photo.

One other thing...why don't I see this on the neck?...sprayed at the same time with the same gun and the same load of 9k?

Thanks for listening.

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JJ
Napa, CA
http://www.DonohueGuitars.com

Okay, what you guys are calling porous is what called textured. It looks like a leather texture, but on a micro level? Is so, this does not buff out, but it also was supposed to be fixed, and isn't showing up in my last batch. It has to do with how the surface coalesces(however it is spelled <bg>). I can't explain why it is still with us, as it is one of the things I reported and Target had changed chemically.

But even with the 'texture', it is still plenty nice enough, IMHO. Once the guitar is strung up and in use for even a week, finger prints and dust and whatever become the great equalizers.

As for what is happening with the dull spots, man, I don't know. Target has a forum, and Jeff would surely like to know about this and he'll help out for sure.

I may be way off base here JJ, but I would try using the 12000 grit and then hand polishing the cloudy spots.

sometimes the buffer is actually more coarse than the micro mesh, and you go backwards in grit when you buff.

I use nitro, but I have noticed that sometimes when I buff I end up with dull spots, mostly near the edges on the sides, Is it heat build up? Im not exactly sure,but I can get a nice shine if i skip the buffing all together, and just use micro mesh and hand rubbing polish.

maybe you could try it that way.
Matt

I’ve also been attempting to buff out the 9000. I’m buffing with 12” wheels at 1100 RPM and using the coarsest and finest Menzerna that Stewmac offers as was recommended by Mario. The body I sanded dry (using a hard rubber block) to 800 before buffing. The neck I sanded to 2000 before buffing.

Here are my findings so far:

The neck looks great. No further action is needed, and I’m satisfied. Buffed after 3 days.

On the body (buffed after 4 days) I can see some deep scratches as a result of only going to 800 before buffing and using hand sanding. I've got a random orbit sander on order and will go back to 320 and wet sand to 2000 before buffing again. This is a reflection of my rushed attempts to get it done rather than the fault of the 9000. I’ve got a big graduate project due next week and I was trying to do this quickly before the 9000 hardened too much. There is never enough time to do it right, but there is always time to do it over. I’ll do it over next week. :-)

If you don’t look at the deep scratches that are my fault, the surface looks great from a normal observing position.   It is uniform all over and does not have the splotchy areas that JJ noticed.   It is only when you closely look at it and only when light strikes it at certain angles that you notice some micro scratches on the surface.   Last night I quickly tried 3M Perfect-It on a hand-held lambs wool buffer and got rid of 95% of them.   You really have to work to see these scratches. I’m talking about holding the guitar up closely, in the right light, in the right angle to see the micro scratches. I think I’ll be satisfied with this, but I’ve got to go back and do it right before I pass final judgment.

From a philosophical standpoint, I wonder if I'm expecting too much. I looked at the guitars at a local music store, and this finish is easily better than anything for $2000 and under. The $2000 Martins had huge micro buffing scratches all over. The 9000 is as good as the finish on the $3000 HD-28. (Mine may have one quarter-inch long scratch per every 5 square inches, but the HD-28 had big buffing tracks in the waist.)    I have to wonder if we beat ourselves up needlessly – especially after seeing the multitude of pick scratches on the HD-28. My thoughts are that these small marks will be insignificant to those marks left after a couple of weeks of playing.
Anyway, these are just the observations of a beginner, so take them for what they are worth. I’ll post the final results and pics in the next week or two.
BruceH

Thanks Mario...I agree with you about the leather texture. I could live with that appearance if it were the only problem.

I've lurked on Target's forum but learned nothing about the blotchiness. I'll either post or call Jeff directly and let you know if he has any suggestions.

Since this is only my 2nd guitar, I'm willing to accept these challenges since it's part of paying one's dues. One thing for sure...I'll be finishing #3 &4 shortly and I will use Nitro until I know more about 9000. Right now I'm not convinced that it's ready for prime time.

I'm really more concerned about hearing how these next few efforts sound and look forward to stringing them up.

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JJ
Napa, CA
http://www.DonohueGuitars.com

Matt...I tried what you have suggested thinking that I could sand out the blotchy areas. In my case, the 12,000 actually looks coarser afterwards and the surface improves with the Menzerna on the wheel. On my 1st guitar (nitro), I just finished up with 12,000 MM and was pleased with the results. Now that I have a buffer, I should theoretically expect more. I'll bet what you were seeing is that the 12,000 was burnishing out the burn marks caused by over-buffing.

Last night I tried hand polishing with Maguires using a StewMac foam applicator/polisher in a hand drill. It smoothed out the surface, but the blotchiness is still there. I believe I'm stuck with permanent birth marks on this baby.

Bruce...thanks for the info. If I remember correctly, didn't you say you applied the finish with a foam brush? I may look into that method for both nitro and 9k since I still have no spray booth. Your description of the surface is similar to mine...I believe it is perfectly acceptable. Good luck as you finish it up. I'm looking forward to the pics.

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JJ
Napa, CA
http://www.DonohueGuitars.com

JJ- Yes, I applied it with a foam brush. I just slapped it on quickly and sanded after every four coats. Looked really rough, but sanded flat with no problems.

This is my first, so I still have a lot to learn, but it's tough to decide what is "perfect enough."

Bruce, don't go back to 320 and start again!

What you want to do is reverse-sand. That means we'll go backwards through the grits.

Start with the finest grit you have, 2000, 12000, whatever, and block sand the area with the stratches until the area is dull. If there are still stratches, go to yuor next coarsest grit down from where you started. repeat until you have killed off the scratches. This won't take long, and this way, you will obnly remove the amount of finish needed to remove the fine scratches left behind. It's the same method we use to repair scratches in a completed guitar; go backwards until the scratch dissapears, then go back up, and buff!

800 is too coarse to stop with the 9000; we can do it with the neck because the curved surface is much more forgiving, but the large flat areas of the body need to go to 1500 or 2000.

But now that you've buffed it after the 800, do the reverse sanding I just explained, and you'll see a really nice surface.

JJ, write or call Jeff; he'll want to help, I'm sure. It's never happened to me(the blotchy areas), and I'm wondering what they are, too. You could re-finish the body, if you don't want to live with the areas; this stuff lifts readily with common hardware store paint and varnish remover(I use "Circe 1850").

As for brushing and spraying, there's a 3rd option, and that is to pad it on, ala French polish. TAkes longer to build the finish, but it is a nice method that if you're not in a big hurry, is nice and relaxing.

[QUOTE=Colby Horton] What is the equivalent to 12,000 micro? I am planning on sanding up to 4,000 grit silicon carbide and using the same buffing compounds. How fast where you spinning your wheels? [/QUOTE] So that I don't get it wrong lok at www.micro-surfaces.com.
There is a world of differance in the heat build up and affective life with micro-mesh It is expensive but when wet sanding it last 5-10 times longer.

JJ, it looks good from here but it's really hard to get a good idea from the pics. Obviously you are not satisfied from reading your posts. What was the temp/humidity like when you were spraying? I have had blotching troubles with nitro when it was too cold or too much humidity. I'd probably email or call target as I'm sure they will be interested in helping you figure it out. They seem like good folks.

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