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most motors run at 1755 or was it 1725 rpm, some will run 3400 ish RPM. It will be listed on the tag of the motor, but what you want is not a certain RPM of the shaft, but a certain FPM of buffer pad. I don't remember the formula, but a 8" wheel will can spin much faster then a 12". So before you get pulleys to do the speed reduction. Find out the proper wheel FPM then do the math for the RPM and the ratio. Your not worried about HP unless you have so little it bogs down.
Mike

Looks Good!! Good think'in Serge!

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Billy Dean Thomas
Covina, CA

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

Thanks Mike and Billy!

Mike, i have no means of mesuring the FPM of my buffer wheels but i'd say they turn very slow if i compare the speed with my drum sander which turns at 1725 RPM, i'd say 862 RPM would be a good guess if i'm lucky!

How could i forget to mention that i was inspired by your buffer in the Jigs and technique section, sorry! Thanks Bud, it seems you've inspired me many times already, your contribution to my guitar and jig collection is really appreciated and made my building more efficient!

Serge

Serge,

25 years ago I decided to have my flute refinished. Surprisingly it was 14 years old and needed it!

The company I took it to in Battle Creek MI asked me if I wanted to watch the all day process. It was that or watching Kellogg's press corn flakes. I knew what show I was watching WOOHOO!

The staff explained every step as I followed my flute through the stripping and re-silvering process.

For me the best part was watching the guy doing the buffing. He used three different wheels and the different rouges to bring the finish to life.

He had customized each of his buffers with sewing machine foot pedals so that he could vary the speed at a moments notice with either applied or reduced foot pressure.

Would a variable speed option like that work with your buffer? Just a thought before my cup of tea...

I made my buffer with a yard sale 1/5 HP, 9 inch buffs, They dont slow down at all when buffing, so even 1/4 HP is plenty.

Serge - you dont measure FPM, you calculate it !!!! So assume you have a motor at 1725, 3 inch pulley, then the shaft has a 5 inch pulley - that makes your buff RPM 3/4 of 1725 or 1294. you are using 8 inch buffs - pi x D is the circumference - 3.14x8 = 25.12 inches.

1294 x 25.12 / 12 = FPM = 2708. Is that a godd number - no idea, I have never seen a range for buffing FPM. Its probably somewhere around where mine work, and I think it could be a bit faster. I may go to SM 12 inchers, to get more access to tight areas - the thing about 8-9 inchers is deep cutaways are tough to get into without touching the shaft of the buff amchine.

As for buffing wheels at waist height, that KILLS my back - I just raised mine again (neighbour gave me a seven foot cabinet, so I reworked my shelving around the buffer area - it has doors, now my books arent covered in Glans Wach !!), the shaft is at mid belly for me, no bending required to buff any section.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Thanks Jeanne and Tony!

Jeanne, i think i kept a pedal i scrounged somewhere, i'll see if i can find it thanks!

Tony, Thanks for the calculating bro, i'll still have to MEASURE the diameter of my pulleys to help me CALCULATE!! the speed and everything you mention! your point of buffing height is a good one too. I'll see what height is best for me and for the cutaways, i don't plan on designing a shallow one so i think my 8-9" buff pads should work fine, i sure will check if i can find what strength this motor has, if i see that it rotates too slow, i might go for a salvaged 1/2 hp! Thanks bud!

I use an old washing machine motor and the stewmac buffing arbor. Most standard washing machine motors are a 1/3 hp and rpm of 1725. This works perfect for my setup. I can't remember right now what my exact buffing speed is right now but I remember I found the 862 rpm to slow. I find it's better to speed it on up a little and keep that guitar moving.

I just love that satin look!

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Serge I may have missed someone else telling you this but recommend that you set your belt tension so that you can stop the wheel when in motion with a flat plank when pressed firm aginst the wheel. (in other words cause the belt to slip while the motor still turns) this allows you to buff at the proper resistance between the guitar and wheel but will cause the belt to slip if you add too much resistance. this will help prevent burning through the finish.MichaelP38925.4262384259

Good point Colby, i will have to test on scraps first to judge how it performs but i might have to do some changes and increase the speed yes.

Thanks Michael, will remember this point if i do increase the speed.

Serge, you are quite welcome. I think I drew my inspiration from Frank's Frets.com and his visit to the corporate Charles Fox Guitar company. They had a big ol' buffer like you see in the Jigs and Tools section. I admit, the guards are yet to be installed on mine as well. I also want to install a switch inline to the motor as an upgrade to just plugging it in.

Thanks Bruce, yes, i think the swith in could be in incorporated on mine as well and also as a safety precaution as the wire on mine is very longand would hate to have it entangled around the shaft!

Serge

Srege: You have an induction motor, so the shaft speed is a function of the electrical frequency. Bottom line changing motor speed is doable, but requires a $200.00 variable frequency drive. It's a lot less expensive to just change pulley ratios if youre not happy with the speed. Also please add a belt guard. I know a fellow whose fingers took a spin around a pully inside the belt. He has his fingers, but he will never be able to play guitar.
Your machine is an inspiration. I guess it's time for me to start building mine.

Al

Thanks Al, yeah, i thought i was finished with my jig but after reading all the wisdom here, i better add some safety features if i want to strum more guitars in the future i guess...

I didn't use it yet for all those good reasons so it's hard for me to know if too slow or not, i will have to wait 'till i try it out but if need be for a faster motor, i might be able to scrounge another one in the coming weeks here!

Serge, the wastebin Bear!

What does one of those do

They turn guitars into fire wood if not careful with them! Serge Poirier38926.0436458333