I am looking into building a belt sander/grinder. I've done a bit of research but have not found any advice as to how many ft/min. to run the belt at. It would be used almost always on metal. I have a DC 100v treadmill motor and an AC 1/2 horse motor that I can use . I think the DC motor is just over 2 HP. I need to figure out what size drive wheel I would need for each etc. but aprox. what fpm should I be shooting for on the belt? Any help or tips would be appreciated! Oh, and looking at using a 2x72 belt as this seems common.
Machine belt grinder build
- Thread starter garageguy
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Machine
all else fails, cheat. We’ve been running one of these in our shop for about 15 years, almost 100% for shaping 316 stainless steel. It runs at 3900 sfm
www.grizzly.com
3" x 79" 2-Wheel Metal Belt Grinder/Sander
<h1>G0489 3" x 79" 2-Wheel Metal Belt Grinder/Sander</h1> <h2>A belt grinder/sander designed to give you versatility and performance.</h2> <p>The Grizzly G0489 3" x 79" 2-Wheel Metal Belt Grinder/Sander is made specially for metal workers.</p> <p>It uses 79" sanding belts that resist heating up...
This is a good place to start.
canadianhobbymetalworkers.com
2x72 sander
I should have added some photos for those into....photos....:D
I’m looking at the same thing. After an excessive amount of internet research I’ve narrowed it down to either a basic KMG design or the Sayber open source grinder. The Kmg is rock solid easy build but no tilt. The Sayber is tilting and can be bolt together or some welding. Only thing with the Sayber is paying to waterjet or laser the parts. I tried plasma table at work but the files would need rework as the kerf is to wide and my guy couldn’t figure it out.
Art
Art
Former Member
Guest
I built one about 2-3 years ago and love it. Belt speed I forget what I calculated so it is what it is. Intent was to build it as cheap as possible and upgrade, truth be told works great, so why mess with it.
My general feeling is that belt speed may help in certain circumstances, but overall no matter what it is, correct grit and pressure results in the fastest removal, best finishes with the least amount of heating experienced in other methods.
Go for it.
Beeswax help can help in keeping the belt from clogging or alternatively use a crape stick and clean the belt on occasion.
My general feeling is that belt speed may help in certain circumstances, but overall no matter what it is, correct grit and pressure results in the fastest removal, best finishes with the least amount of heating experienced in other methods.
Go for it.
Beeswax help can help in keeping the belt from clogging or alternatively use a crape stick and clean the belt on occasion.
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both of mine were with ac motors, 1/2hp ac would probably be pretty underpowered , you could make up the sf with a bigger drive wheel, or a jackshaft, but you would still be under powered imo
i would should for the min of a 3/4hp motor if using an ac motor, and a 3650 motor makes life easy for direct drive without a massive drive wheel
dc i cant really comment, they have some funky rating methods, what is the rated rpm of that motor ? might be easier to figure what an equivalent ac hp is if you know the wattage of the motor
i would should for the min of a 3/4hp motor if using an ac motor, and a 3650 motor makes life easy for direct drive without a massive drive wheel
dc i cant really comment, they have some funky rating methods, what is the rated rpm of that motor ? might be easier to figure what an equivalent ac hp is if you know the wattage of the motor
The tag on the DC motor doesn't give much info, no rpm rating, wattage, nothing. just HP and voltage. I don't even know what max rpm would be, maybe 3000 or more? I believe max volts is around 100-110. This is what makes it so hard to figure out drive wheel size. I am guessing that I will get more HP by increasing voltage/rpm?
i just checked, the one i have currently is a 3/4hp open frame 3450rpm jet pump motor, that does fine for what i use the grinder for (just general metal working)
im sure i might be able stall it out if i was trying to grind 3 or 4 square inches at a time, like trying to make a big knife...but that's not what i use mine for, i tried it, grinding at work and then coming home and doing more grinding wasnt for me
overall the 3/4hp works for me, i dont know what you plan to use yours for, if its just general metal working, rounding corners, chamfering, flattening edges, etc, the 3/4 will probably do you just fine
if the motor you have is a c face motor just give it a shot, if you find it underpowered find a bigger c face motor later on, really if you already have it you dont have anything to loose by trying it
im sure i might be able stall it out if i was trying to grind 3 or 4 square inches at a time, like trying to make a big knife...but that's not what i use mine for, i tried it, grinding at work and then coming home and doing more grinding wasnt for me
overall the 3/4hp works for me, i dont know what you plan to use yours for, if its just general metal working, rounding corners, chamfering, flattening edges, etc, the 3/4 will probably do you just fine
if the motor you have is a c face motor just give it a shot, if you find it underpowered find a bigger c face motor later on, really if you already have it you dont have anything to loose by trying it
TorontoBuilder
Ultra Member
Okay, time for my two cents... because why not.
While researching surface feet per minute speeds for materials to include in my machining calculator I was able to find the following general guidelines for belt grinders. The usual caveats apply in the event that your results don't turn out as expected
because speeds for belt grinding depend on the type of material being ground, the type of abrasive belt being used, and the size and type of the grinder.
While researching surface feet per minute speeds for materials to include in my machining calculator I was able to find the following general guidelines for belt grinders. The usual caveats apply in the event that your results don't turn out as expected
because speeds for belt grinding depend on the type of material being ground, the type of abrasive belt being used, and the size and type of the grinder.- Metal Grinding:
- General purpose grinding: 3,000-4,000 SFPM
- Heavy-duty grinding: 4,000-6,000 SFPM
- Finishing and polishing: 2,000-3,000 SFPM
- Plastic Grinding:
- Soft plastics: 1,500-2,500 SFPM
- Hard plastics: 2,500-3,500 SFPM
- Wood Grinding:
- Roughing and shaping: 3,000-4,000 SFPM
- Finishing: 2,000-3,000 SFPM