I have a unbranded bench grinder that I acquired used. When it gets up to speed and when I grind on it, it loses speed and I have to stop and wait for it to get up to speed again. Any ideas on what the problem is? It has a capacitor. To my understanding it probably doesn't have brushes. Thanks for your help!
Bench grinder loses power
- Thread starter Otis3d
- Start date
RTM
Well-known member
My first question would be, how many HP does it claim?
How hard are you leaning on it?
My dad used to have a cheap tiny orange Black n Decker that my 13 y.o. brother could easily stop trying to sharpen a hatchet.
You probably can't post pix here yet, but if you link them from an outside source it may work.
Since you provided zero information (brand, size, material, a picture etc) my conclusion is it is a piece of used junk.
my guess, from lack of info provided, is a low end, low HP grinder that doesn't have the power you need.
I have one just like it that I bought when I was about 20 yrs old.
I have one just like it that I bought when I was about 20 yrs old.
Beerhippie
Well-known member
Is it plugged in?
American exchange, 8 in 1 HP
Beerhippie
Well-known member
How many amps does it draw? It sure ain't crankin' out no 1 hp.
Beerhippie
Well-known member
Fabricating/just making up HP numbers is standard practice these days. That doesn't even list amperage nor horsepower--it says N.P. (Newt Power?), not H.P.
From your description, I'd guess it's more like 0.1 HP. If you have any way to actually measure the draw in amps, you can look up hp vs. amp for a 110V single-phase motor.
Or just face the fact that you need a bigger grinder.
From your description, I'd guess it's more like 0.1 HP. If you have any way to actually measure the draw in amps, you can look up hp vs. amp for a 110V single-phase motor.
Or just face the fact that you need a bigger grinder.
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RTM
Well-known member
Here are some other people's opinions on theit stuff, from 20+ years ago. There is stuff on Amazon now, but it looks newer than yours, but similar quality.
American Tool Exchange. Junk or What? - Yesterday's Tractors
Howdy people bought a 14 cutoff saw at an auction this summer it was imported by American Tool Exchange. Model 11014. This saw has a very hard time c
www.yesterdaystractors.com
Being new to the forum it must be my initiation turn in the barrel for you. I just wanted to know if it's the brushes if any or the capacitor.
Good thing I have thick skin!
Beerhippie
Well-known member
I'm glad you came here for answers--but sometimes the answers aren't what you hoped for.
I'm afraid that is a great example of a complete import POS.
But stick around, read the Garage Sale and Bench Grinder threads and get a better idea of what fits your needs and a fair price to pay.
Personally, I'm pretty happy with a relatively POS WEN brand 8" bench grinder. It does what I need and I know not to push it.
I'm afraid that is a great example of a complete import POS.
But stick around, read the Garage Sale and Bench Grinder threads and get a better idea of what fits your needs and a fair price to pay.
Personally, I'm pretty happy with a relatively POS WEN brand 8" bench grinder. It does what I need and I know not to push it.
Beerhippie
Well-known member
BTW: If the grinder doesn't jump around on the bench when running, it may be worth saving the stones from it.
hate to be the bearer of bad news, but as others have said , you don't have much of a grinder there. if you really need more power, be on the lookout for something else.
So it may just be an underpowered or worn out imported piece of junk but personally I might check a few things before tossing it in the trash bin. You said it had a capacitor do you know if it's just one or two (or unlikely a combined start/run cap)? I'd start there. If you have another similar sized motor try swapping the cap(s) and see if there is any improvement. It probably just has a start cap and if it's starting OK the cap is probably good but caps are known to cause problems and are relatively inexpensive to replace. Start cap can be fine but run cap may be bad, if it has one.
How is motor turning by hand? Freely or with any resistance? Any noticeable play in shaft either in/out or up/down. Could be bad bearings. Esp if they are heating up and seizing while running. Could definitely add enough resistance to slow down or stop an inexpensive motor.
May just need to be taken apart and cleaned up. Could be loaded with grinding dust or metal shavings from prior use. If you pull it apart eyeball condition of rotor and any windings. Do magnets still feel strong when you remove rotor? Are they still attached to housing?
Also check wiring and switch. Are you running with a long thin extension cord? If so plug it into wall directly and see if you get more power out of it. Is motor getting unusually hot while running?
How is motor turning by hand? Freely or with any resistance? Any noticeable play in shaft either in/out or up/down. Could be bad bearings. Esp if they are heating up and seizing while running. Could definitely add enough resistance to slow down or stop an inexpensive motor.
May just need to be taken apart and cleaned up. Could be loaded with grinding dust or metal shavings from prior use. If you pull it apart eyeball condition of rotor and any windings. Do magnets still feel strong when you remove rotor? Are they still attached to housing?
Also check wiring and switch. Are you running with a long thin extension cord? If so plug it into wall directly and see if you get more power out of it. Is motor getting unusually hot while running?
Beerhippie
Well-known member
That'll solve yer problem.
Thanks for your reply. I will check all of that out. It's zero here and the garage is unheated. It can wait lol
dnschmidt
Well-known member
Odd that none of these free grinders are ever Baldors isn't it?
Well there you go!
RTM
Well-known member
Wheel Face Grinding? No idea what that means, but seems like the big flat side, not the skinny curved edge. The 12-123 makes sense w that definition.
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I have a non name brand grinder in my garage. When the weather is cold out it runs very slow. When the weather warms up it goes back to normal.
thool
Well-known member
OP may be able to bring it indoors overnight to warm up, and then test it once warmed. If it doesn't slow down, then it's probably the lubricant not doing its job. If it's still slow, I'd get rid of it and buy one that has more power.
Excellent advice. I was also thinking I would pop it open and see what's inside, give it a cleanup, check the cord and electrical connections, etc. Just do some quick checks, lube the bearings, inspect for play - things that don't take long to check and won't be that big of deal to fix.
You can clean up the rotor on a lathe and test the windings - but that probably is more effort than it's worth. Up to you of course on how you do the time vs money equation, but this isn't a heavy duty vintage grinder.
It might just be a wimpy grinder - but I don't see why you'd start with that assumption.
Did you not see the picture/brand name?
RTM
Well-known member
Cuz there is just so much excrement out in the tool world. I've seen many grinders pop up on my local CL, and I do a quick search of GJ, or the wider web to find out they are pure ****.
If someone says unbranded, I'm gonna guess cheap import first, then, maybe, a decent one that some previous owner pulled the tag off.
Been doing vintage tools for almost 25 years, fell victim to **** the first five years. Far from an expert but I'm still learning.
I never thought about the lubricant angle.