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Okay, so I'm getting old...thinking of attaching my radius dishes to my buffer arbor...I saw a photo back in the day where someone had done this...(maybe Kathy Wingert)...but the site no longer has the photo...if I remember correctly (remember, I said I'm getting old)...the caption called the setup "the monster" or "the beast"...all of which has me thinking, "could this be safe"? Should I do it? What do you guys and girls think? And if you haven't checked out Kathy's site, you should...beautiful work and her daughter's inlays are amazing!

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http://www.presnallguitars.com

You'd better slow down the arbor tremendously with pulleys. Otherwise no, it doesn't look too safe…

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

it can be done providing you bore the hole dead center and to fit exactly to the shaft. If you dont the the dish spins out of ballance. It is also not to good on the arbor bearings. Get ready to bust a rim, plus it is dificult to tell if you are sanding equal on both sides and back to front.

Hey Larry,

Ted Thompson has his dishes vertical like that and he has built hundreds of guitars with them. I have talked to him about the one I built similiar to Tim McKnights/Mario Proulx but Ted prefers his method. He is also a machinist so the skill and ability to make things just right. You do though need to get the shaft rpm down around 120 or lower. Remember the outside of the dish will be spinning a lot faster than that. For me, I still prefer the horizontal dish and use bolts as stops as John How suggested so getting things sanded right is an absolute no-brainer once it is set-up. I don't even pre-profile the sides, I just let the sander do it, add linings and touch up once more. Perfect results every time! (All of twice so far! )

Shane

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Canada

It could wobble and really wreak havoc if not perfectly balanced! There is a way to mount it (to) your drill press, which seems safer.

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Here is what a Parlor Guitar is for!
http://www.youtube.com/watch?v=oEa8PkjO6_I

I've seen pics and I believe some here have even taken that route. To me however, I think it's just plain crazy. I want my buffing wheels running around 700rpm, and the absolute last thing I want on that shaft is a flywheel carrying all that torque and inertia. If I bear in too hard, or catch an edge, I want to be able to stop that wheel, or at least slow it down. With a 1/2hp motor running two 12" wheels I can buff a finish out just fine without slowing it down, but I can stop them if I really try. Put a massive flywheel on the end and if you catch a guitar on that thing it is going to the floor. And though I'm sure everyone here is careful with loose clothing and jewelry, catch a tie on that shaft and you're going around a few times before it stops.

I just see nothing that these two things have in common, no good reason to try and combine them, and lots of reasons why not to. They need different power, different speeds, and unless your shaft is incredibly long seem like they would get in the way when buffing. Lots of compromises have to be made in order to make this crazy tool. The issue of balance and leveling is not so much my concern. A massive flywheel on a buffer is just a bad idea in my opinion.

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Eschew obfuscation, espouse elucidation.

If just have to have a power thing for radius dishes for ribs and linings, just make one and have a buffing wheel for what it is meant for.

I don't know how many guitars doing, but can make a deal to do lining and ribs by hand and not wear you out. I did 8-10 a week a Bourgeois and worked out. I knowGalloup has power unit, but it is slow and that is what you want, he also had his own builds on it and bunch of students so faster process was needed.
If you try to combine the deal it just might not work out.

Given a decent hardware store and a cheap motor from an appliance repair store, you can make a dedicated sander for about $50 and an hour or two of time. Considering that the least that can go wrong with an off balance wheel on a 1700 rpm buffer is a bent shaft, making your own is money and time well spent.

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http://www.chassonguitars.com

Okay guys, you came thru for me with wise council again! I'll not bolt the dishes to the buffer arbor and go with a dedicated one with low rpms...thanks for all the input!

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http://www.presnallguitars.com

Don't know if it was Kathy's site, but I can second that her work is incredible. To top it off, she's a dang nice person. She did a fretting demonstration for SIMSCAL (Stringed Instrument Makers of Southern California) about a month ago. If anyone's curious about SIMSCAL, please feel free to inquire. Kathy also brought one of her harp guitars to the meeting. Talk about a piece of craftsmanship! Below's a slightly blurry photo. I cropped it because, this being the internet, I didn't want to compromise anyone's privacy. Her website has much better photos...

George Lowden has a pair of these, one for tops, one for backs.

they're washing machine motors

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you could just get a variable-frequency drive to control the speed of your buffer, nice little devices you could find a lot of uses for in your shop.

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Frank

Watching a wash machine in it's spin cycle started me thinking. If i can't get the wash machine that someone trashed to work then I have the parts I need to drive a dish.
Here's an idea of how to make a motorized dish.
http://www.doolinguitars.com/articles/disksander/

A motorized dish sure would be nice, but I'd probably want it to rotate pretty slow compared to my buffer.

Steve Kinnaird dropped by one day and we we talking about this. I think I told him that it might take some of the fun out of it (I had to have been joking...) and he told me "There's a lot of things in guitar making that I'd like to take the fun out of". Ha.

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Instagram: @jfrenchluthier
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This what your talking about Larry

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Lance@LuthiersForum.com

That's it Lance! Is that from Kathy Wingert's site? It sure would be nice to do that since I already have the buffer just standing there in the corner waiting for the next nut, saddle, or bridge...

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http://www.presnallguitars.com

Randy Allen mounts his dish in a drill press. The drill head turns 90 degrees so the dish is vertical. I would say it isn't very safe and that it would be harder to control then letting the weight of the outside mould work with you in the horizontal. I hope you have a strong back.

Holy harmonics Batman!! Coming from a background of engineering - mostly with work around turbine rotors, I'd say you really want to be careful with that thing!

IMHO, here are some things to look at:

1) Many things may not look safe, but in reality probably won't go toooo terribly wrong... we pray!
2) It really depends on the speed of the motor. (can you dramatically gear it down?)
3) It is not impossible, but balancing a setup like that is very important if you want your sanding dish, bearings, and buffer to last very long. You could balance it by trial and error with holes/weights (simple bolts on the perimeter) but this could take a lot of time. Of if you have a HUGE lathe, that would help dramatically.
4) DON"t stand in a the radial path of the wheel while it's going - if it's going to come apart it will fly apart outwardly thanks to centripetal force.

If you do build this monster, please video it and post so we can see how it works. That would be Awesome to see in action

Or if you don't feel like posting, I'm sure we'd be able to link to a story about it in the Darwin Awards eventually.

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Eschew obfuscation, espouse elucidation.

If you have 80 grit on that thing and have it spinning fast....

Wouldn't be too hard to get a sleeve caught up in it....

Bet there aren't too many one armed guitar builders out there, lets not produce more.

I'd be careful with that too Lar! The linear speed differential at even slow speeds could add up! At worst you could set up a molecular collapse maybe even micro particle collapse leading to one of the mini black holes! You don't want one of those in your garage!

They're great for the trash though! HEY! I think I solved the landfill problem!

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Billy Dean Thomas
Covina, CA

"Multi famam, conscientiam, pauci verentur."
(Many fear their reputation, few their conscience)