Slowing down a grizzly

I

Ian Fifelski

Joined
Oct 4, 2017
Messages
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Hey everyone. I would like to slow down my grizzly grinder as much as possible for cleaner machine finishes and cork belts. Also loaded cork belts.

The grinder runs at 3600 sfpm with an 8 inch wheel. My question is how slow can you get it by using smaller wheels? Is this an unreliable method of slowing ? as I have not seen people do this to slow down there grizzlys.

The motor rpm is 1725 so if I got a 4 inch wheel I could get about 1800 sfpm and with a 2 inch wheel about 1000.
What is the recommended speed for loaded cork belts? 400+ grit belts?

Thanks.
Ian
 
Throw him a sandwich from your backpack. Oops, should've read the whole thing. :oops:


Actually, I think a smaller wheel would not be advisable. I had a Griz for about 5 years before selling it to my brother. The thing is that the drive wheel is mounted right to the motor so there isn't very much room to work even with an 8" wheel. A 4" wheel would give you clearance issues I would think. In the case of the Grizzly, my recommendation would be to work with it at the speed it is and lighten up on your pressure against the belt for more control. Just use a lighter touch and sharp belts when doing finishing work. This will remove material more slowly but also give you cleaner grinds because the harder you press, the more the belt wants to slack above the grind leading to ripples and other problems.
 
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I concur that less pressure is probably the best, I use cork and have never seen them work any better at slower speeds! Even loaded with Green Chrone——-//// I had a Grizzly for about two weeks that I bought in a package deal with other machinery... Simple Machine, they work, .... When I started in 96, the Late Bob Loveless told me to sell each knife for enough to make three more. 1/3 goes to more supplies etc. 1/3 goes to Rent/Food stuff. 1/3 goes in a coffee can for new/better Grinders etc.. Get a better machine with speed control and keep the Grizz for what it does best for you...:thumbsup:
 
I agree with Laurence. The only thing a Griz is good for is profiling, at least until you are very good at grinding. When I started out, I ruined every knife I tried until I sold the Griz and bought a variable speed grinder. The Griz is just too fast.
Tim
 
The barefoot boy said:
Hey everyone. I would like to slow down my grizzly grinder as much as possible for cleaner machine finishes and cork belts. Also loaded cork belts.

The grinder runs at 3600 sfpm with an 8 inch wheel. My question is how slow can you get it by using smaller wheels? Is this an unreliable method of slowing ? as I have not seen people do this to slow down there grizzlys.

The motor rpm is 1725 so if I got a 4 inch wheel I could get about 1800 sfpm and with a 2 inch wheel about 1000.
What is the recommended speed for loaded cork belts? 400+ grit belts?

Thanks.
Ian
Click to expand...

I slowed my Grizz down by replacing the 8" contact wheel with a 5" wheel. A number of years ago someone was selling a replacement wheel for not much money. I added an idler wheel to route the belt over to take up the slack. If I change back to the 8" wheel, I skip the idler and make no other belt length adjustments .

Some folks have replaced the buff with a pulley and run the grinder (powered off) with a alternate motor.

Dave Suitor
Saving for a VS North Ridge Tool grinder
 
The preferred speed for finishing steel is in the 4000 range for good finish surface. Less pressure is key to not burning things up at higher grits. I have variable speed, but really only slow it down when using small contact wheels.
 
Great recommendations guys, thanks. A new grinder is on my wishlist. Just not realistic for me to afford it yet. I really like the northridge!

This makes me question... Is getting an $1800 grinder later going to be something I regret in the future? Should I go for it now? I am still a beginner but I have been able to make consistent, clean grinds. I guess I need to wait as I am still working in a plywood 8 x 12 shed with a dirt floor. :p

I haven't had any problem with bad grinding, even right when I began. I rough grind with 80 grit though and I understand many start with 36 grit so that slows things a bit.

Also, I believe a high speed is good for ceramic belts, @Natlek runs 7000 sfpm I believe? I just thought slower speeds were better for high grits.
 
The barefoot boy said:
Great recommendations guys, thanks. A new grinder is on my wishlist. Just not realistic for me to afford it yet. I really like the northridge!

This makes me question... Is getting an $1800 grinder later going to be something I regret in the future? Should I go for it now? I am still a beginner but I have been able to make consistent, clean grinds. I guess I need to wait as I am still working in a plywood 8 x 12 shed with a dirt floor. :p

I haven't had any problem with bad grinding, even right when I began. I rough grind with 80 grit though and I understand many start with 36 grit so that slows things a bit.

Also, I believe a high speed is good for ceramic belts, @Natlek runs 7000 sfpm I believe? I just thought slower speeds were better for high grits.
Click to expand...
I started with a slower grinder single speed around 2000 sfpm. The slower speed helped me not screw up as fast. Now I tend to use pressure often to control the overheating issue. If I backslide, and start messing up, I will slow it down to get back on track, but that is pretty rare now.
 
In the 1970s we didn't have variable speed grinders, so we learned to use what we had. Looks like that's what you have done.
The Grizzly is an entirely adequate belt grinder.
I would put money toward a real shop before I bought another grinder.
 
The barefoot boy said:
Great recommendations guys, thanks. A new grinder is on my wishlist. Just not realistic for me to afford it yet. I really like the northridge!

This makes me question... Is getting an $1800 grinder later going to be something I regret in the future? Should I go for it now? I am still a beginner but I have been able to make consistent, clean grinds. I guess I need to wait as I am still working in a plywood 8 x 12 shed with a dirt floor. :p

I haven't had any problem with bad grinding, even right when I began. I rough grind with 80 grit though and I understand many start with 36 grit so that slows things a bit.

Also, I believe a high speed is good for ceramic belts, @Natlek runs 7000 sfpm I believe? I just thought slower speeds were better for high grits.
Click to expand...
Grinders hold their value well. A guesstamite is 50%-70% depending on how fast you want out and other factors as well. Having more than one grinder has improved my productive by setting them up for different jobs. ——————/-Only you can decide when & if to upgrade! Have fun & stay safe!
 
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