I need to buy a new benchtop grinder.
I also would like to use it to polish parts.
Is there a specific type of grinder that would lend itself to polishing parts if I change out one side for a buffing wheel?
Thanks
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I need to buy a new benchtop grinder.
I also would like to use it to polish parts.
Is there a specific type of grinder that would lend itself to polishing parts if I change out one side for a buffing wheel?
Thanks
We've got a dedicated buffer but there is no magic to it. Any grinder that will accept the buffing pads will work fine. My Son just went to Northern and bought some rouge of different grits plus some new pads of different softness and did his Olds engine parts. It made a lot of difference. I am going to build a backsplash for the buffer because it sure slings the compound and strings from the pads. :eek:
Don
you don't want a rest on the buffer. If your going to buff long or large parts you may want to mount it on a stand rather than a bench...one thing is certian when buffing HOLD the part tight.. I've had good peaces of trim turn into trash in a second :eek:. I have a bench grinder and a buffer the buffer is mounted on a plate welded to a pipe welded to a 15" car wheel and the wheel is filled with cement to help stop it from moving around... I would anchor it but then it would be out in the way when not in use
Most buffing is done at 3600RPM, while some, not all, grinders run at 1800. The nice thing with dedicated buffers is the extended shafts for working material around. A variable speed motor would be nice or if you have the space, maybe build a dual purpose belt drive version with a multi groove arbor, then you would have work around space plus the ability to change speeds, Baldor is the big name in buffing motors. Then there is the Eastwood/Harbor Fright "internationally built":whacked:.
These guys have a good selection of supplies too:
caswellplating.com
You may be right about the speed difference and the extended shafts. Our buffing wheels do sit way out as opposed to the grinder wheels that are closer in. We got our buffer at Sears and it has been actually pretty good.
Don
Thanks for all your helpful pointers.
Has anyone owned this combo unit from Harbor Freight?
8" Bench Grinder/Buffer
Might me a good compromise.
Has anyone owned similar combo unit they would recommend
Thanks
I have a jacuzzi motor with a buffing pad. Not sure what the rpm's are, but it's really fast. What I did was use an old sewing machine pedal to control the speed. Cffisher isn't kidding about holding onto that part tight. Long pieces can be a bummer to do. The more pressure you put onto the wheel with the piece, the more different it's going to look. A bench grinder will work. You might have to put a small piece of pipe over the rod to get the pad to stick out further. Good luck. Practice makes perfect. I should add that buffing will not take out any scratches. None. Wet sanding will.
Mutt, since you asked...I use two Baldor 1/2 hp units...that way, I can have 4 wheels mounted. I label the grit to eliminate cross-contamination of the wheels. Using this, I can start with a more aggressive compound and move finer without having to stop and change wheels. These things can really launch a part if you get careless. Gloves and face protection are a must.
mike in tucson
Mike brings a good point.
Is this staged approach the way most of you work when polishing?
If so then I could swap out the left side of the Harbor Freight polisher grinder when I'm polishing parts and swap it back to a grinder the rest of the time.
Mutt
It takes a real buffer to do a decent job, it's got to have the longer shafts to make it possible to get odd shaped pieces polished. As Robot brought up, it takes different wheels and compounds to polish stainless and aluminum parts, not a simple deal at all. I have an old Baldor polisher, 3600 RPM version, stored away in the back of the shed for now. It cost a bunch to get it and all the right stuff to make it work, but it's worth it. I don't think a single sisal on a questionable grinder motor is going to yield satisfactory results.....
If you go to the CaswellPlating.com site, they have a introductory instruction page so you can learn the basics. It tells about grits, speeds, etc. No first aid instructions, however.
How much buffing/polishing are you planning on doing? Harbor Fright stuff will either work well or be a POS. Nad it will not do it commercially or for even a long time. If you are planning on doing a bunch of grinding, then a dedicated grinder is best and wont deposit nice little pieces of steel on your buff. And vice versa
Current plan is to build this '37 Buick and then enjoy it.
My wife wants an old T-bird so that is a possibility, I probably won't buy a project, car for that one. Just one that needs minor work.
Does anyone know if there a noticable difference in performance between a 6" & 8" polisher?
Mutt
8" your 1" farther away from the flying parts.
Can I offer a better solution than buying HF stuff? (their stores stink from the Chinese rubber smell).
You can buy a pair of pillow blocks and a shaft with the proper clamps to clamp the buff wheels. Add a
couple of pulleys and an appropriate motor, a belt and you can bolt it to a bench. Viola, you have a buffer.
Make sure you compensate for the pulley ratio if you do anything but a 1:1 ratio.
I concur with most of the above - go 8" or larger and buy appropriate for the need. Eastwood makes a nice 10" kit and it's good intermediate quality with two speed motor, 10" wheels and a pedestal- will probably last the average hobbyist user a lifetime - but they're proud of it (on sale for $340). EW Buff Motor 1HP 1750/3450RPM, Buff Kit & Pedesta
HF is cheap, but for occasional use it's fine. I buy buffing pads and compound at HF and it's fine.
Lot's of folks here have hinted at the safety aspect - believe them! I've been "wounded" several times from pieces slipping from my hands and launching at my being! I always wash my hands real well before starting, wear gloves and goggles, gloves cause stuff gets hot and goggles cause I need my eyes!
Regards All,
Glenn
Mosy definately, my sheet rock in the garage shows it.....LOLQuote:
Originally Posted by glennsexton
Between the buffing and grinding wheels and a couple of other powerful shop tools, there are some scars on paneling and even a couple on me from having work grabbed out of my hands. My face mask split when a chunk of a new grinding wheel came loose.
The significant difference between the wheels is the surface speed. A 6" at 3600 rpm has a surface speed of 5655 while an 8" has a surface speed of 7540 FEET PER MINUTE or 33+% faster - which means anything grabbed out of your hands will be moving a heluva lot faster/hit harder with the greater diameter:eek: (I use 8" wheels)
Don mentioned that he has been pretty happy with his polisher from Sears.
I'm leaning towards the Sears 6" because I can probably adapt grinding wheels and covers off my 6" burned out grinder to work on this.
Sears: Online department store featuring appliances, tools, fitness equipment and more
Several have recommended 8".
Sears also has 8" polishers that have a faster surface speed, but does that increased speed help a lot to polish a part?
I want to buy the right polisher and one of my biggest pet peaves is buying something and then replacing it because it does not meet the requirements.
Thanks for all your help.
Mutt
RPM is close, (3450) but with only 1/2 hp not sure that's going to be an adequate motor for any lengthy stays at the buffer. Looks like it would be ok for a low to moderate use buffer, but personally I'd go with something a bit more substantial with a bit more power. If you do some studying on the process of buffing stainless, aluminum, or whatever else I think you'll discover that bigger is going to be better---but if price is your only concern, then Sears will probably do.....
Not as much surface speed but actual surface area will help. That 6" probably has a puny 1/4Hp motor, the 8" will have up to a 1 Hp therefore will move a lot more wheel. Heck, mine is a retired compressor motor - and it's not only big, it's a real 1Hp, not that "developed" horsepower that manufacturers are using to hide power deficiencies. It will turn something bigger then 8", but my buffs are 'safely' only 8"
Circumference is ~18.8" for the 6" and for the 8", it's 25+. This means that faster surface speed of the 8" will move 33% more surface past the spot being polished and 33% more rouge quicker to do that shining at least 33% faster. (Pi x dia will give you circumference)
Mutt,
The speed is indeed a critical part of the polishing process. The thing I would be concerned with is trying to run your grinding wheels at twice their normal speed - the grinders are a nominal 1725rpm while polishers are nominal 3450rpm. You'll tend to get things pretty hot grinding, and you need to ensure your wheels are good for twice the normal speed. Also if you're into a lot of polishing you may not want your grinding debris contaminating your polishing area.
Those are valid points Roger.
I'll probably go with the 8" Sears and buy a separate grinder.
Sears: Online department store featuring appliances, tools, fitness equipment and more
Thanks everyone for your help.
Mutt
To be brutally honest only a proper polisher will do the job, the bench grinders just don't have the grunt and will take a long time to produce half decent finishs.
Another case of, use the proper tool for the job at hand.Quote:
Originally Posted by roadster32
Mike
Heck for $ 39.95 you could buy this buffer 6" Buffer and for 32.99 you can get this grinder 5" Bench Grinder , and have the best of both worlds for less tha the price of the combo unit!
Steve i wouldn't waste my time with that buffer, its ok for buffing something already polished but useless for anything else.
when you polish you need to get some heat into the part.
Quote:
Originally Posted by stovens