Electric die grinder

[mikekozura]

I was thinking of getting a electric die grinder for my polishing. I'm just doing stuff on my boys race quad. I already burned up a old 3/8 Craftsman drill now I'm using my 3/8 Milwaukee drill. But I been reading all this SFPM stuff. The RPM on the grinder I'm looking at is 25000 is that to high. I have a little kit but it only had soft wheels. I was going to get the grinder. And then the arbor and four inch wheel kit from Caswell.

http://www.caswellplating.com/buffs/arbor.htm

I want to do this bumper again and get it a little nicer before I clear powder coat it.

[easleysp]

I would have to say 25,000 RPM is quite a bit too much. It might get nasty if you caught a corner. A pnuematic die grinder would be a better choice, that is if you have compressed air. If you have a bench grinder caswell sells arbor extensions to give you more room to work with. Flexible shafts are another option if you're dealing mainly with small parts. I have a 1/4" drill that works pretty good, but I don't use it that often. At $150+ it's not something you want to take a chance on letting the smoke out. Hope this helps. Good luck.

Steve

[mpierich]

You can only use the die grinder with small tools like cartridge rolls and felt bobs, unless it's variable speed - and if you slow it down it won't have the torque for 4" wheels.

Air die grinders run too fast as well, although you can vary the speed a bit with an artful trigger finger - but the above would still apply.

Flex shafts are great, but do not get the skinny Harbor Freight one - it'll twist up on you and last a few hours at most. My commercial-duty shaft is over an inch in diameter and runs in bearings.

When I'm not using the shaft for 4"+ wheels, I use an air-operated drill (don't bother with electric drills unless they're commercial-duty...they'll burn out right quick). It's got plenty of torque, the correct speed, and cost about $30.

[pickleboy]

this setup might be just what you need:
http://www.caswellplating.com/buffs/grinderadapter.html
this adapter coupled to a electric buffer like this
http://www.dewalt.com/us/products/to...?productID=174
this setup with 8" or 10" wheels will get you in the 6000-7000sfpm range. it should have a good amount of torque, being rated at 8.0 amps and 1400 watts, to get the job done. also with this setup you can use all standard wheels and greaseless or standard compounds. i use something like this most all the time but with smaller wheels and faster speed. as mentioned though be careful of the wheel grabbing and also if you go this route be sure to cover the adapter with duct tape to keep from dinging the work if it does grab.

[mikekozura]

What do you think about this and its only 40 bucks. Correct me if I'm wrong it should be 4" wheel = 6280 SFPM and 6" wheel = 9420 SFPM.


http://www.caswellplating.com/buffs/grinderadapter.html

Edited for forum violation

[pickleboy]

speeds will be 6000 and 9000 sfpm for those wheels. it should work i just dont know of the torque it can produce. for 40 bucks it is woth a try. i would again say be careful of the wheel grabbing. other than that good luck bro.

[mikekozura]

H@ll for as much as I'm going to use it I think I'm going to go with this one. And the adapter and 6" wheels from Caswell. And h@ll it's only 25 bucks. Thanks for the good luck bro. I have some sticks of compound. This should be better than using my all cotton wheels with my drill. What do ya think?

http://www.caswellplating.com/buffs/grinderadapter.html
http://www.caswellplating.com/buffs/sisal.htm
http://www.caswellplating.com/buffs/sscw.htm
http://www.caswellplating.com/buffs/loose.htm

[pickleboy]

stick with 8 or 10" wheels to keep the surface speed up to where it should be and it should do fine.

[mikekozura]

OK, I bought a grinder/buffing machine it's a 3/4 hp 3600rpm with a 3/4 arbor. It worked out good I needed both, one sides a grinder and the other side has the extended shaft. I can't say where it came from last time I posed a link to there site Jim removed it (sorry Jim didn't know). Any way I was going to order good 8 x 7/8 wheels from caswell. ( 8 = 7536 sfpm ). What do you think ??

The two day sidewalk sale at the blank blank store is hard on a mans wallet. My wife gave them a pic of me to post in the store if I show up they have to kick me out. LOL I need a big nose and glasses

Thanks for all the help. I'll try not to hurt my self or the part with a machine.

[pickleboy]

that should be fine the wheels you mentioned will give you about 7200 sfpm and that is on the top side of speed for starting out. as you get more experience with the machine you may be able to move to 10" wheels but if you do be extra cafeful. i rum faster than the recommended buffing speed in the caswell manual but i have gotten a feel for my machine and feel i get a good finish faster with oversize wheels. keep in mind though i have been at this for over a year working at it for about 2-4 hrs a day 6 days a week.