I'm thinking about getting a buffer/polisher to clean up mostly small parts. A friend has a 2 HP Baldor that will throw stuff across the shop which is overkill for me. Is 3/4 hp enough or should I get something in the 1 to 1
I was interested in the same thing the other day and found this website that does a decent job explaining buffing speeds.
I have a 6" slow speed grinder (around 1120 RPM) that I use for sharpening woodturning tools. I was wondering why it wasn't doing a good job polishing when I put buffing wheels on. "Intuitively", I thought slower would be better as when grinding... I was wrong. Seems that I was only getting about 1700 SFPM while I should have been up around tripple that speed.
BTW, you didn't mention how small a part you wanted to polish. I've seen people use die grinders with 1" buffing wheels that do a good job on small stuff.
So it looks like I will stop buy HF on the way home from work and get their $60 3600rpm 8" buffer. Obviously, I'd like the Baldor...
I buff alot .Its just a 1inch shaft about 24 inches long with a 10 inch dia wheel on each end and belt driven with a 1/3 horse power moter. Its plenty of power you can't bog it down.its 1800 rpm I have used 3600 rpm before and i don't like it,the part heats very fast so you cant hold it.You have to charge your wheel more often because it throws the abrasive off.
Wait!! HF grinders have been discussed here before and as I recall, there was rarely a good word for them. Bad bearings, imbalanced rotors, out-of-square flanges. Worse than a case of "You get what you pay for". This is second hand information, so do a Google-group on it.
You could start with a blower motor from a squirrel cage blower and a
5$ arbor the blowers are always in scrap piles behind larger heating and ac firms until they make a dump/scrap run. That would be 1/4 hp. More hp wouldn't hurt , get some cheap experience first. A clothes dryer motor would work also. Washing machine motors are a bit of a mystery with more than one speed but if you can dope one out it has more power still.
I don't know how this machine (of the many they sell) compares to what HF offers, but it comes as a buffing kit for not much money, and the site offers a fair amount of info on buffing. I haven't bought one of these or dealt with the company. I just thought the site was worth a look.
3/4 HP is plenty for small parts, I use an old 1/3HP
1800RPM double shaft cast iron motor--works fine with 8" buffs. When I was in the marine hardware business I had a monster 7.5HP Hammond buffer that weighed over 1000#. Working on large parts with 12" buffs stacked up 2" wide it was possible to hear the motor slow when you leaned into it. Lots of holes in the drywall behind that puppy . Remember that energy is proportional to velocity squared, so unless you're planning on using small wheels, I'd stick with the 1800RPM machine--it'll be plenty dangerous enough.
After being disappointed with the Chinese grinder/buffer HP ratings (although I generally like science fiction), I bought a bench arbor from Graingers (a pillow-block mounted shaft with threaded ends, and a central pulley). Mounted it on a hollow metal pedestal (Hoffman electrical stand). Works well with a 1/2 HP motor, using a stepped pulley to select the speed. I remember seeing these arbors at a lot of places some years ago, but they're getting harder to find now.
One problem with using a standard grinder is the short shaft length, which limits your ability to get to all areas of a larger piece. Also, I like to stack buffing wheels to get a wider surface; tough to do on most import grinders.