Here's an update: just finished buffing the back of the Amazon Rosewood guitar. It turned out great! No problems. I think I'll try level sanding the Pau Ferro and try again.
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| Author: | MikeWaz [ Mon Jan 02, 2017 5:10 pm ] |
| Post subject: | Buffing Reveals Pores? |
Hey guys - I’m using my pedestal buffer for the first time. In one of the photos below, you'll see a nice leveled surface prior to buffing. In the other photo, you’ll the surface after buffing with medium ColorTone compound. A few things to note: - This is Pau Ferro, which is not a very porous wood. - Even so, I filled the pores with a single coat of Zpoxy. - Finish is Enduro-Var Gloss leveled up to 2000 Abralon. - The leveled surface is completely flat. You can’t feel even slightest texture. My assumption is that my pore filling was not sufficient and this is why the grain is visible after buffing. But, I am a little surprised because the surface before buffing is so flat and smooth. But maybe there’s something else at play? Could this be the result of over-buffing? I’m I heating up the finish too much? Or not buffing enough? Any thoughts would be helpful. I have two other guitars I”m hoping to buff out. Thanks! Mike |
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| Author: | Joe Beaver [ Mon Jan 02, 2017 5:16 pm ] |
| Post subject: | Re: Buffing Reveals Pores? |
I don't think they are pores showing through. look more like brush marks being reviled. Other than that I don't know why that would happen, except maybe bonding between the zpoxy and finish coat? By the way, that looks like it is going to be a very nice looking guitar |
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| Author: | kjaffrey [ Mon Jan 02, 2017 5:40 pm ] |
| Post subject: | Re: Buffing Reveals Pores? |
It definitely doesn't look like pores to me. I have had pores show up after buffing but they look like normal small dips in the finish. I have never used endurovar, but my guess would be that during buffing the finish got warm enough to move around under the buff. Where you using much pressure or moving very slowly? Heat can build up pretty quick. That would be my first guess, though it could be finish adhesion problems also. |
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| Author: | Joe Beaver [ Mon Jan 02, 2017 5:49 pm ] |
| Post subject: | Re: Buffing Reveals Pores? |
I think kjaffrey might have nailed it, it does look like finish getting hot and moving. Also is your buffing wheel high spped? Greater that 1000 rpm? |
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| Author: | Aaron O [ Mon Jan 02, 2017 5:56 pm ] |
| Post subject: | Re: Buffing Reveals Pores? |
Need more info - what wheels, what speed. If you're going to 2K abralon, I would think starting at medium would be a little aggressive. I agree with Joe and - looks like brush marks are being revealed. Edit: I guess my post is delayed. Yup, jkaffery has a good point as well. |
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| Author: | MikeWaz [ Mon Jan 02, 2017 6:42 pm ] |
| Post subject: | Re: Buffing Reveals Pores? |
Thanks for the replies. I just finished buffing the top. It doesn't show any of these problems and turned out nice overall. (Pic below.) On top, back and sides, I used a foam brush for the first three coats and then switch to spraying. (Fuji Mighty Mite 3 / T75G). I level sanded before switching to spraying. All my coats were applied within a 24 hour window. The "brush marks" are not consistently present. Meaning there are areas that are a few small areas that are completely flat and don't show the "brush marks." Buffer arbor is spinning at about 600 rpm. 12" Canton - Medium 12" Domet - Fine This is my first time using a pedestal buffer. It's hard to assess myself, but I think I was initially using too much compound and may have been applying a little too much pressure. I also wonder if I was trying to get too much gloss out of the medium and should have switch to the fine sooner. The fact that the top doesn't have this problem has me stumped. I may try buffing the back of one of the other guitars (Amazon rosewood and mahogany) and see if I get similar results. |
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| Author: | Aaron O [ Mon Jan 02, 2017 6:52 pm ] |
| Post subject: | Re: Buffing Reveals Pores? |
Your setup seems fine, mine runs at 800 (little more). I try to load the compound, and let the compound do the work, so light touch against the wheels. And I actually move deliberately, on the slower side. I'm thinking your finish didn't have enough time to cure between coats, or after, and may have contributed to the movement. BUT, I've never used Endurovar, so its all a guess. |
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| Author: | MikeWaz [ Mon Jan 02, 2017 8:06 pm ] |
| Post subject: | Re: Buffing Reveals Pores? |
Here's an update: just finished buffing the back of the Amazon Rosewood guitar. It turned out great! No problems. I think I'll try level sanding the Pau Ferro and try again. Sent from my iPhone using Tapatalk |
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| Author: | B. Howard [ Tue Jan 03, 2017 9:00 am ] |
| Post subject: | Re: Buffing Reveals Pores? |
kjaffrey wrote: , but my guess would be that during buffing the finish got warm enough to move around under the buff. . That's my guess as well.....Overheating while buffing will bring back surface texture ("orange peel" or in this case brush marks)when the surface cools. Some pointers; First, no need to sand out to 2000 using a pedestal buffer. Don't know this new "Colortone" stuff that SM is peddling these days but if you were to start with medium Menzerna compound you only need to sand out at 600-800. Sanding out too fine for your compound will increase heat. The coarser abrasives in heavier compounds are designed to cut material off the high points of the scratches left by the sandpaper. When the surface is too flat, too much contact is made with the finish material and causes it to overheat much easier. Second, overloading a buff with compound will overheat your work as well. If you are charging the buff for more than 2 seconds you are putting on to much compound at a time and actually closing up your airway buff so the air cannot flow through it and keep the surface cool. Third, Pressure.....This will take experience to learn. It is a feel. But keeping yuour buffs well groomed so you are not chasing false scratches in the finish which are actually paste lines left by long threads or "whippers" hanging out of your buff. |
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| Author: | Mike OMelia [ Wed Jan 04, 2017 11:58 pm ] |
| Post subject: | Re: Buffing Reveals Pores? |
It could simply be that the sanded finish was not sanded enough (??) Buffing will always bring out imperfections. Those are not pores. Just looks like imperfect finish sanding to me. Buff. Look. Wet sand. Buff. Repeat?? Oh, and I hope u have enough finish on there for the process. DAMHIK With the waterborn finishes I use, I use a intermediate buff or two to see how well I am progressing. Has anyone but me ever noticed how a good wet (mineral spirits) scotch brite finish buff can look so DANG good until it hits the buffer? |
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| Author: | gerry [ Thu Jan 05, 2017 7:59 pm ] |
| Post subject: | Re: Buffing Reveals Pores? |
The voice of inexperience here... but I've had a lot of trouble with both polyurethanes and varnish curing properly (or at all) on Morado. I wonder if your first coat of finish, while dry on top to the touch, was still soft underneath? Gerry |
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