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After recently sanding and buffing two acoustics back to back I couldn't help but think there must be a better way.

I'm using CrystaLac Brite Tone Gloss (6 coats sprayed) level sanding wet to 1,500 and buffing on a StewMac machine using Menzerna Medium and Fine on separate cotton wheels.

It's taking close to 3 hours at the machine to get an acceptable finish (see photo). I can't imagine this is an optimal process. Particularly on the Medium wheel it takes what seems like forever to get to a glossy surface. I move at about 1 inch per second across a small area about 20 times with medium pressure on the wheel. Often that's not enough and have to do it twice or three times to get a good result.

Is this amount of time and equipment typical? Is there a better solution that will generate heat faster and speed up the process?

Thanks in advance!

Note: I’m not an expert here, others with more experience will chime in I’m sure.

Is that 3 hours for a body and neck? And that is the time start to finish or the time actually spent with part on wheel?

3 hours seems about right for what I do from start to finish, maybe more, but that time also includes raking and trimming the wheels, buff changes (I use 3 compounds), taking breaks to closely inspect the work, etc....

The neck goes a lot faster than the body.

I only sand up to 1200 dry but that’s an artifact of the finish I use, I wouldn’t expect it to contribute to the amount of time needed to buff.

Are you buffing in a few different directions when you say “1 inch per second across a small area about 20 times”?

I spend the most time with the first compound, Menzerna 113GZ, then P204 and then GW16. The first two relate to basically your medium and fine I believe.

Here is how they look in sequence:

113GZ


P204


GW16


Brad


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Thanks Brad. Yea, that's total time at the machine, including inspecting the surface frequently but I don't swap out wheels. I usually start across the body and then work the length perpendicular to the previous passes. I have taken to working one surface at a time, sanding then buffing before going to another surface and sanding and buffing... just to break up the monotony of it. Sides do go faster than the top and back (not just because of total surface are) likely because I'm focused in a smaller area.

And, yea, the Necks seem like I'm on vacation next to the back (worst) and top (next worst).

Hi Terry!
I use EM6000 Gloss and use the same Menzerna grits as you do, and wet sanded to 1500 as well.
It also takes me a similar amount to time to get a proper gloss on the buffer, 3 hours or so, including the raking and swapping of buffing wheels per grit
(I only use one buffing wheel at a time, as leaving the other one on gets in the way...)

A few years ago I gave up on Menzerna bars and cotton wheels. I went to automotive buffing creams and foam pads on a small DA buffing machine. It's quicker and easier for me.

I've done the same thing for the same reason....

Dave

Do you find it difficult to get into the little nooks and odd corners with a orbital polisher? This is super interesting!

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Fancy banjo pegheads have an incredible number of those nooks and odd corners--no way to get in there with an orbital polisher. But, with either a felt cone on a dremel or simply by hand, these can be buffed out just fine.

On guitars, since I finish the necks and bodies separately, I haven't really found anything I can't hit with the orbital polisher.

I do like the automotive polishing compounds though, if for no reason other than they're not as messy as big buffers and aren't prone to grabbing work and shooting it across the shop.

Dave

To me it is less work because the guitar can sit on the workbench and you set the machine on top of it. The sides are the most tricky part to polish due to the curves and the need to hold it steady.

It took awhile to find the right combination of pads, compounds, buffing machines and technique. But I think I have it dialed in now.

Barry, I almost bought a DA polisher a while back when you mentioned it. What brand and size did you settle on? And, would you recommend that polisher to the rest of us now that you’ve used it awhile? I’ve always polished by hand but I’m ready for a better shine with less work.

https://adamspolishes.com/products/adam-s-swirl-killer-mini-12mm-lt-polisher

I still use it and love it. For its smaller size, it is a workhorse(y).

Here is the thread where I introduced it. It's down about half way.
http://luthiersforum.com/forum/viewtopic.php?f=10101&t=52716&hilit=adams+swirl

The Brite tone product is a bear to buff I used it on 2 guitars and gave away what I had left. It never looks real glossy no matter how hard you work ans after a year or so looks like it needs to be rebuffed, Returned to Mohawk and Cardinal nitro as it is way easier to work with and way better looking.

Fred

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I have ordered Barry’s polisher. In three weeks, I will polish and play after I spray and it hardens. Thank you, Barry.

I went with Festool sanders
The last guitar I did took an hour and 5 minutes
I found klingspoor have sandpaper that is just for finishes. I never knew that before
I level off with 600 just before I bottom I go to 800 then 1000 then 1500 2000 2500 3000
buff with Mezzerna med finish and 175
if I need to then maquires swirl remover.
3M also has good polish products no silicones

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blues creek guitars
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Bob, the secret to using this machine is to bear down on the machine during the initial buffing. You want to see the foam pad compress a bit to get it really working the surface. Final polishing is done with less pressure.

What compound(s) are you going to use?

I thought I would start experimenting with the compounds I use by hand now. I level with P800 (by hand). I use the LMI fine cut (kind of red clay colored), followed by the StewMac swirl remover, followed by Meguiars Mirror Glaze 10. (All of this is on EM6000). I get a subdued shine but not the glass like surfaces I see others get with Nitro. I takes me a bit more than an hour of hard work to shine up a guitar after the finish cures.

I like to keep my finishes thin, so I will have to learn how to do this without burning through. When I’m done, my finish is somewhere in the 3-4 mil neighborhood (6-8 before I start leveling and polishing).

One thing you could try is sanding to a higher grit. P800 = cami 400. P1500 = cami 800, which is closer to where I like to start hand buffing.
I really prefer to use micron "papers" (they are often on mylar, can be washed and reused a few times. What I've heard is that they "grow" the grains to a uniform size, rather than sieve it through a screen where you get multiple sizes (and a few rocks). I will sand up to 15 micron - approx. 600 cami - but since the grains are more uniform this seems to work O.K.. Sometimes I will carry it a little further and sand with 1000 cami before buffing. Many people recommend sanding even finer. I don't think the auto compounds most of us are using for hand buffing contain as aggressive of abrasives as those used on a buffing wheel, so sanding finer can save time buffing and make a better finish.
https://www.youtube.com/watch?v=Ltbwlg9qYUM
https://www.thesandpaperman.com.au/abra ... chart.html

Some of the auto compounds can be fairly aggressive. I use Meguiars 105 and it can be moderately aggressive, as well as breaking down to achieve a fair high gloss.

Barry- I have used buffing wheels for 40 years with seldom the exact the results that I like. I've tried and thrown away enough compounds to create a mini-environmental disaster. I've always been intrigued by orbital buffers, but never made the move to try them. I see the Adams mini orbital on Amazon for $114.00. If that is the machine you are talking about, that's affordable. I do more ukes than guitars, so a small machine might be the ticket. Could you take the time, at your leisure, to give a few more details on the pads I would need to get. Maybe also a list of the sanding grits you use for final leveling before buffing.When I use automive compounds on the wheel, I normally use Perfect-It, which is what I might continue with. I have a love/hate relationship with Menzerna. Some chemicals can be difficult to get here in Hawaii. Thanks for your time. Stay safe,--Bob

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Bob, I gave all my details in this thread:

http://luthiersforum.com/forum/viewtopic.php?f=10101&t=52716&hilit=adams+swirl

It's down about half way. Look for the second photo of a black polisher. The Swirl Killer Mini (Adams) is a good size for a guitar and it has a little meat behind it. The interface pad is 3" dia. but I use 4" dia. foam pads. $114 is a good price. I paid 135 a couple of years ago.

Barry- Thanks. I saw that. Just wondering if the pads are just what comes with the buffer or ? Also how about the sanding grits for final leveling? Thanks, Bob

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https://caswellplating.com/buffing-polishing.html
I get a lot of things from here. High end stuff

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Bob, pending Barry’s reply, he wrote more in this thread over on Mimf.

https://www.mimf.com//phpbb/viewtopic.php?f=13&t=6117&hilit=Adams

No the pads have to be purchased separately.

Thanks for the link Glen.

I usually geek out on automotive polishes (pun intended), and that includes pads as well, which in certain cases are just as important as the polishes. If you want a large menu of pad types. . .
https://www.autogeek.net/4inch-spot-buffs.html

Note: I have a slew of Meguires pro polishes, along with sealers and waxes from other brands as well. Of course, foam pads for my orbital, all for my vehicles, so liquids are not foreign to me. I’ve tried them for finishing, and they work, but I prefer Menzerna on buffing wheels.



Not sure what heat does to your finish, but that’s not the goal with nitro. Also, the more pressure you put, you start running into the buffing wheel, past the buffing material, which is on the outer edge.

Admittedly, I was struggling with my fine/extra fine Menzerna on my StewMac arbor (the old one). Once I built my new arbor setup with larger wheels, 1” shaft and new Menzerna bars Med/Fine, life is so much better. More surface area (3 pads on each side) and runs way cooler, allowing the buffing material to do the work. Also, the bars were too old and dry - they don’t last forever on the shelf.

My process is more in alignment with John’s, focus on sanding. While I can spend more time letting the buffer do the work after sanding to 800, I find going to at least 2000 makes the process go much better.