Official Luthiers Forum!

I want to set up a power buffer for nitro.

A few questions:

1.)What type of wheels? Muslin, Canton, Domet, soft, loose ?

2.)I'm only going to have 2 wheels so which compounds?

3.)What's a good SFPM speed (or RPM wheel diameter combination)?

Thanks,
Kevin Looker

_________________
I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

Also, instead of using a buffer, can you use the micro-mesh (500 through 12,000) to get the same results? I've not sprayed Nitro yet, but am about to on my next guitar and was going to use the micro-mesh because I don't have a buffer.

If not, I suppose I can get the StuMac sponge pads for my drill.

Steve

Is this true? I used the micro-mesh pads for the ROS and went up pretty high. But it was not till I hit it with the buffer that the shine really came out.

I would be interesed to hear if you can micro-mesh to a final product.

To the OP, You can build a pretty good buffer, assuming you find a 1/3 hp motor on ebay or something for cheap, using the arbor from Grizzly (shop fox). It looks like the same one Stew Mac used to sell.

Arbor: $100
Motor: $30
Longer Belt: $10
4 14" Canton wheels from Caswell Plating: ?? $60?? (two each side)
A 2'x4'x3/4" board to mount it all too (laying around the shop?)

Gonna need Menzerna compounds too. And those can add up. But they last a long time. Not including those in the buffer price.

Mike

Yes, you CAN use micro-mesh and get very nice looking results, but it's a LOT of elbow work. You would probalby want to wet sand up through 1500 or 2000 grit, then move to micro-mesh. To go through all of that is pretty labor-intensive, though. A hand-held buffer set-up would be useful, but not as good as a stationary buffing set-up.

Which is why I just ordered an arbor, motor, and supplies to set up and start using buffing wheels - I'm anxious to see how that goes! My elbows will be much happier, I think!

_________________
Ken Mitchell
Durham, NC

Ok, I thought the elbow grease issue was the issue.

Mike

Micro Mesh requires a LOT of elbow grease... very tedious if doing an entire guitar. Also wet sanding runs you the risk of getting water into the wood (screw holes, etc. for electric guitar or back of the neck), so I would only do it for hard to reach areas like cutaways.

I use Stewmac buffing wheels, these are BIG wheels that no one in Taiwan seem to sell (the biggest anyone sells is 10" and those are really soft but very thin wheels, which would require like 10 or more to build up to a good width) and you have to use 2 on each side because the center of the wheel is held in place by a metal plate that is only held in by friction, with tabs on one side to keep it from going further in. So in order to mount it you have to have two wheels facing the opposite way so the metal tabs would face away from each other, thus tightening as you tighten the bolts on the shaft.

I use this thing with a drill press as all buffing arbors I find in Taiwan are fairly standard, meaning it's either 3600 rpm or 1800 rpm, and nothing else. I mount it to a 5/8" bolt, with spacers to center the buffing wheels correctly, additional homemade spacers to get up to the thread (which would not be necessary if you used more than 2 wheels per side). If I had a metal lathe I could use a 3/4" bolt, and turn the shank down to 5/8" so I can use it in the drill press... To prevent the bolt from loosening tighten the bolt, and screw another bolt right on top of that and it will be locked in place.

So now I have two of these, medium and fine. I heard its what people use when they have 2 sides... but with this setup I can have all 4 compounds if desired, all I need to do is change the wheel at the drill press. A lathe with a chuck is probably a better choice though...

You still need to hit the finish with fine hand compound and a swirl remover if you're using micro mesh... even 12,000 grit doesn't make it shiny enough to leave it alone.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

I used Micro Mesh on #1 & #2 but it's a lot of work and it took some Behlen's polishing cream & more elbow grease to really bring out the shine.

From this thread it looks like people are running their wheels between 1200 and 3700 fpm so there's a lot of flexibility in wheel speed?
viewtopic.php?f=10101&t=34106&start=0&st=0&sk=t&sd=a&hilit=buffer

Are most people using the medium & fine Menzerna compounds and canton wheels?

Kevin Looker

_________________
I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

I really do not know how to word this. But I have always felt that something else is going on with cotton wheel buffing, something that can't be done with high grit sanding. It's like there is some surface "melting" and blending with compound and cotton wheels. Does anybody think this makes sense? I've sanded with micro mesh to 8000 grit before. And it looks really good. But something magical happens when I put it to the buffer.

Mike

Kevin, not sure about the fpm, but my 14" wheels turn at 800-900 rpms. I guess that works out to about 2900 fpm. But it is LOW torque. I can stop the wheels if I push too hard, and that's exactly what I want. 1/3 hp motor. Those ones from Caswell are just too much torque. Hard to burn the surface and less likely to toss my guitar across the shop.

Mike

The StewMac system is 720 rpm at the shaft. The loose (unstiched) wheels I use are 14".

Diameter (inches) x rpm / 229.2 = fps

14 x 720 / 229.2 = 43.98 fps

...and that works very well when using Menzurna's medium and fine compounds after completing sanding through 1500 grit on lacquer.

...and it's good to have low torque....as Mike mentioned. Even a total novice would have a hard time overheating a surface using the StewMac system....which slips on the arbor wheel under high pressure...if it's set up well.

_________________
I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

Nitro is pretty much the easiest finish to burn. You're better off starting on the slow, low FPM side of the speeds you listed. I used 12" wheels at 1100 RPM when I used Nitro, but it was easy to burn. Slower, or smaller wheels would probably be safer. Medium and fine compounds with Canton wheel is OK. I've recently started using coarse compound too, and not sanding as much. I never used coarse with Nitro though so I can't comment on it specifically.

_________________
I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

A lot of the older generation of guitar makers use the brown Menzerna followed by the fine. I have pursued this for 3 years in various buffer setup configurations, and finally decided to reserve that wheel for the buffing of ebony or other jobs. For the nitro I use, it simply causes more problems than it is worth - I now go straight to the medium compound and follow up by hand with the 3m Perfect It.

I use the older Stewmac setup, with a 1/4 hp half speed motor. If you dont already have one - dont waste your money - you can make one inexpensively based on the design in the Bob Benedetto book, or the one on Adam Starks Facebook page.

The Stewmac / LMI wheels are fine - better source; Jescar USA or Caswell Plating.

Good luck!

I wet sand with 800 grit and buff on the Stew-Mac wheels with medium and fine Menzerna. The results are outstanding. The big wheels will take the lacquer right off the edges of the headstock, or diamond carving if you have one, unless you are very, very careful. It's hard to get all the scratches out on the headstock and stay away from the edges, so I use the 3 buffing compounds Stew Mac sells on small buffing wheels on a drill to do the headstock of a guitar, it's safer and quicker when I don't have to touch it up or reshoot it, especially if I used tinted lacquer.

_________________
Damon Wack
https://www.facebook.com/LindamonGuitars

I've used micromesh up to 12000 a few times on nitro but it just doesn't have the gloss produced by a buffing wheel.
I agree that the buffing has a burnishing effect not achieveable with micromesh.
There was a very spirited discussion on the MIMF about 10 years ago about the burnishing effect produced by the friction generated heat of buffing and whether or not it actually "melts" the nitro.
With that said, I would speculate that the surface produced by 12000 is just as SMOOTH as buffing.

I usually like to leave the neck satin because its better for playing. The gloss just makes the neck too sticky.

However for repair work nitro is a pain to buff on necks, because it will burn if you look at it funny. Polyester/urethane is so much easier... you can press very hard and it will only result in a highly buffed finish when used with Menzerna fine, just don't try buffing poly by hand... the stuff is difficult to cut. I can see why most factories use poly.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

I use arbor buffers. I got them at Grizzly and use mezzerna compounds. . Micro mess will get you close but you need the buffers to get that true final gloss. There is one thing about power buffers , use a light 1/4 hp 1725 rpm motor You want to be able to hold the guitar and stop the buffer.
You don't need a lot of power here , you are buffing not grinding. Here is a link to a buffing arbor. I have it and it works very well.

http://www.grizzly.com/products/Buffing-Assembly/H3559

_________________
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

Thanks for all the replies.

I was planning on getting the arbor from Grizzly but now I think I should save the 2HP Baldor for another project.

Kevin Looker

_________________
I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

I use the Grizzly arbor with their 12" wheels. Note that they call out a maximum 10" wheel size,
but so far I've had no problem with the 12" wheels. I do have the belt set up very loosely so I
can easily stop the wheel if I push too hard. I think that's a safety factor for both the finish and
the arbor shaft. I use the Menzerna medium and fine after sanding to 1000 grit.

_________________
Gene

Politicians and diapers must be changed often, and for the same reason- Mark Twain

I am using a 16 wheel on my grizz turning at about 400prm.

_________________
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

Where did you find 16" wheels?

Mike

THATS the word I was looking for. Exactly. I have micro-meshed up to at least 8000 if not 12000, and still, the difference is remarkable after hitting it with the buffer (and Menzerna). It would be interesting to settle the debate by getting someone who can take micrographs of the various prepared surfaces. I don't really need them, but it would be interesting none the less.

Thanks for "teeing up" that word!

Mike

Bump: Still interested in 16" wheels...

Mike

Grizzly has 16" wheels.

I saw a setup where the person had put pulley's on the motor that led to a separate arbor with the buffing wheels on it. He left the belt intentionally slack so it acted as a clutch, if he caught an edge of his body the wheels would stop while the motor kept chugging along. I'm curious if anyone on here has done that, this is the setup I've been thinking of putting together. I think it was on MIMF before they changed the site, I guess I'll have to wait until they update the archives to look at it again.

OK, the archives have just now been ported over to the new MIMF. But you have to register to be able to see it.

http://www.mimf.com/phpbb/index.php?sid=572395138b1532e7a7ba979c8fc85954