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All Replies on Grizzly Table Saw Blade Spin Down*Updated 8/11/17*

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View seturner's profile

Grizzly Table Saw Blade Spin Down*Updated 8/11/17*

by seturner
posted 08-06-2017 03:59 PM


32 replies so far

View MrUnix's profile

MrUnix

7242 posts in 2496 days


#1 posted 08-06-2017 04:21 PM

No brake… but an unusually long spin down time can indicate bad bearings. Typical spin down time with a standard blade should be about 5-7 seconds give or take a few. You might also want to take a look at the belt tension.

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

View seturner's profile

seturner

29 posts in 717 days


#2 posted 08-06-2017 04:31 PM

I just went out and timed it with watch. From the time I press Stop button to blade motionless is 31 seconds, which is worse than I said.

The saw seems to run smoothly, their is a short squeal when I first start it, like a belt noise.

View Andre's profile

Andre

2499 posts in 2103 days


#3 posted 08-06-2017 04:40 PM

I would think good bearings and perhaps belt just a little loose causing slippage on startup?
Think about bandsaws, large cast wheels take forever to stop turning hence the addition of foot brakes!

-- Lifting one end of the plank.

View Rich's profile

Rich

4149 posts in 887 days


#4 posted 08-06-2017 04:41 PM



No brake… but an unusually long spin down time can indicate bad bearings. Typical spin down time with a standard blade should be about 5-7 seconds give or take a few. You might also want to take a look at the belt tension.

Cheers,
Brad

- MrUnix

Not arguing with you, but how would bad bearings increase the time to spin down?

-- Half of what we read or hear about finishing is right. We just don’t know which half! — Bob Flexner

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MrUnix

7242 posts in 2496 days


#5 posted 08-06-2017 05:22 PM

Not arguing with you, but how would bad bearings increase the time to spin down?
- RichTaylor

Good bearings, with proper grease, have some resistance to spinning… if you take one and hold it by it’s inner race and spin it, it will free spin maybe once or twice but no more. Once the grease goes away (or turns to wax), you can do the same and it will free spin a lot. If you have a used machine, there is no telling when (or if) those bearings have ever been changed. They do not last forever.

I don’t know how many times I’ve heard people say “I spin them and they spin forever, so they must be good!”. Doh!

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

View Rich's profile

Rich

4149 posts in 887 days


#6 posted 08-06-2017 05:30 PM



Good bearings, with proper grease, have some resistance to spinning…

Cheers,
Brad

- MrUnix

OK, thanks. That makes sense now that you explain it.

-- Half of what we read or hear about finishing is right. We just don’t know which half! — Bob Flexner

View unbob's profile

unbob

810 posts in 2201 days


#7 posted 08-06-2017 06:53 PM

I have a Delta with the 1 1/2hp motor, it has an effective internal brake, the saw shudders a little when the switch is turned to off.
Other motors like the 1 1/2hp motor in my Griz jointer. takes longer to spin down. The brake is a safety feature
Dry bearings are most noticeable in radial saws, can take a long time to spin down.

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MrUnix

7242 posts in 2496 days


#8 posted 08-06-2017 07:01 PM

I have a Delta with the 1 1/2hp motor, it has an effective internal brake, the saw shudders a little when the switch is turned to off.
- unbob

I don’t believe I have ever seen a Delta TS that had a brake… What model saw, and is it an aftermarket braking system? Or are you talking about the centrifugal switch closing down (which many people confuse with a brake as it does slow the motor down a bit when engaged)?

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

View JackDuren's profile

JackDuren

388 posts in 1257 days


#9 posted 08-06-2017 07:14 PM

Call Grizzly…

View Woodknack's profile

Woodknack

12638 posts in 2677 days


#10 posted 08-06-2017 07:22 PM

30 seconds does seem like a long time. I would check belt tension. Lot of people own Grizzly, might add “Grizzly” to the title and get more responses.

-- Rick M, http://thewoodknack.blogspot.com/

View unbob's profile

unbob

810 posts in 2201 days


#11 posted 08-07-2017 12:33 AM

<blockquo>


I have a Delta with the 1 1/2hp motor, it has an effective internal brake, the saw shudders a little when the switch is turned to off.
- unbob

I don t believe I have ever seen a Delta TS that had a brake… What model saw, and is it an aftermarket braking system? Or are you talking about the centrifugal switch closing down (which many people confuse with a brake as it does slow the motor down a bit when engaged)?

Cheers,
Brad

- MrUnix

The saw is a 1979 Rockwell 10” contractors saw, with the original Rockwell 1 1/2hp motor. I have read others thinking something is wrong with their motor, when the switch is flipped off the, saw shudders from the braking action as it slows down.

View MrUnix's profile

MrUnix

7242 posts in 2496 days


#12 posted 08-07-2017 12:39 AM

The saw is a 1979 Rockwell 10” contractors saw, with the original Rockwell 1 1/2hp motor. I have read others thinking something is wrong with their motor, when the switch is flipped off the, saw shudders from the braking action as it slows down.
- unbob

That is pretty typical on a single phase induction motor – as the centrifugal switch closes and the start windings/capacitor are brought back into circuit (combined with the friction induced from the centrifugal switch itself)... and it’s exaggerated on machines with the motor hanging out the back. It’s not a brake, but many confuse it as such :)

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

View TungOil's profile

TungOil

1143 posts in 792 days


#13 posted 08-07-2017 01:33 AM

my 3 hp Powermatic takes nearly that long to spin down as well. Larger motors carry more inertia and take longer to stop. In addition, check the belt tightness. If you are getting belt squeal on start up your belt is too loose, which will (counterintuitively) reduce the friction in the system allowing it to spin down longer.

-- The optimist says "the glass is half full". The pessimist says "the glass is half empty". The engineer says "the glass is twice as big as it needs to be"

View MrUnix's profile

MrUnix

7242 posts in 2496 days


#14 posted 08-07-2017 01:58 AM

my 3 hp Powermatic takes nearly that long to spin down as well.
- TungOil

31 seconds? That is excessive. My 3hp Baldor takes about 7-8 seconds to come to a stop – and it’s a three phase motor, which will usually take a bit longer than a single phase one. You can see it here.

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

View TungOil's profile

TungOil

1143 posts in 792 days


#15 posted 08-07-2017 02:11 AM

In my experience a single phase motor typically weighs more that a comparable 3 phase motor. The extra weight is in the armature, which gives it more inertia, so all other things being equal it will spin longer.

-- The optimist says "the glass is half full". The pessimist says "the glass is half empty". The engineer says "the glass is twice as big as it needs to be"

View TungOil's profile

TungOil

1143 posts in 792 days


#16 posted 08-07-2017 02:31 AM

OK I just timed my PM2000, 3hp motor- it takes 11 seconds to come to a full stop (but feels like 30 seconds when I’m waiting)! So I agree 31 seconds does seem too long.

Check the belt.

-- The optimist says "the glass is half full". The pessimist says "the glass is half empty". The engineer says "the glass is twice as big as it needs to be"

View MrUnix's profile

MrUnix

7242 posts in 2496 days


#17 posted 08-07-2017 03:17 AM

LOL – here is a 5hp PM66 – 10 seconds.

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

View unclearthur's profile

unclearthur

223 posts in 2085 days


#18 posted 08-07-2017 04:47 AM

Here us a Grizzly G0690 – the shutdown leader at only 3 seconds! No brake needed, just crappy Grizzly quality control

View seturner's profile

seturner

29 posts in 717 days


#19 posted 08-07-2017 03:21 PM

I called Grizzly this morning and it was of no help. “Richard” informed me that there is no brake on the saw, so it is what it is. I asked if it could be a belt or bearing issue, and his opinion is that the bearings must be really good to spin that long, which is contrary to MrUnix opinion. I believe that MrUnix opinion makes sense though, but don’t know what to check.

I checked the belt tension per the manual, and it seems in line, approx. 1/2” deflection.

31 seconds is a loooong time when you are waiting to remove a piece of wood or change setting!

View Woodknack's profile

Woodknack

12638 posts in 2677 days


#20 posted 08-07-2017 05:46 PM

In my experience when bearings are bad they get grumbly or feel gritty, they don’t get better.

-- Rick M, http://thewoodknack.blogspot.com/

View greenacres2's profile

greenacres2

333 posts in 2465 days


#21 posted 08-07-2017 06:12 PM

Fresh bearings on my old Dewalt RAS (a 1957 GWI) and the spin-down went from just over a minute to about 11 seconds. That was the only change, and since it’s direct drive there was no variance in the tension on any belts or anywhere else. Same blade as well. The old bearings were whisper quiet, and spun in my hand easily and without vibration. Opened them both up, no grit or sawdust on the inside—and no grease either, just a nice glaze that was smooth as glass. (only disassembled because I couldn’t believe something that turned so easily could be “dry”!!)

So…I’ve become a believer in the dry bearing theory—if the cause of failure is simply dried out grease. Introduction of dirt, grit, dust, etc—grumbling and/or gritty feeling would likely be a symptom.

Just my non-scientific thinking.
earl

View MrUnix's profile

MrUnix

7242 posts in 2496 days


#22 posted 08-07-2017 06:39 PM

I believe that MrUnix opinion makes sense though, but don’t know what to check.
I checked the belt tension per the manual, and it seems in line, approx. 1/2” deflection.
- seturner

The only way to really check if a bearing is good or not is to pull the shield/seal (unless it’s an open race bearing) and examine the grease, balls, races and cage. They can fail in multiple ways. Sometimes they will give you an indication of impending failure like Rick mentioned, sometimes not. But by the time you have them pulled to inspect, it’s usually just better (and easier) to replace them with new bearings so you know they are good. Cleaning and repacking is an option, but IMO, only worth the effort on bearings that are hard to find, made out of unobtainium, or super expensive.

I’ve had bearings that appeared to be perfect… but weren’t. For example, here is an SKF bearing that was in a motor that ran fine, had no noticeable noise, grinding, run-out or any other indication of a problem, yet was leaking grease and very close to its ultimate demise:

I imagine that most people would have never opened the motor up given the lack of any signs of a problem. However, I make it a habit of replacing the bearings on any newly obtained used machine. In the above case, it was a good thing I did – as it didn’t have much life left in it. You never know what kind of use/abuse a used machine has seen in its lifetime, and it’s cheap insurance that can prevent some much more costly damage in the future (particularly in motors!).

Here is another example of a bearing that appeared to be fine. No noise or grinding, but would free spin forever because the grease had leaked/deteriorated and the remainder had turned to wax:

Also, it has been my experience that Grizzly (a lot of the imports actually) uses pretty cheap bearings. It is not uncommon to have new machines fail within a fairly short time due the cheap Chinese bearings used in them. If for nothing else, that is a good reason to replace them with some quality bearings that will last significantly longer.

As for the belt – 1/2” deflection should be good… however I’ve never found the ‘deflection’ method to be that great. Too many variables… where do you push, how much pressure, etc… For cabinet saws, I really prefer adjusting them while the machine is running – which ensures they are set properly and allows you to reduce/eliminate any vibrations induced by the belts.

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

View Woodknack's profile

Woodknack

12638 posts in 2677 days


#23 posted 08-07-2017 06:44 PM

I see what you’re saying, just never had that experience myself.

-- Rick M, http://thewoodknack.blogspot.com/

View rodneywt1180b's profile

rodneywt1180b

181 posts in 684 days


#24 posted 08-07-2017 06:47 PM

I’m with Brad on this one. It’s time to check and most likely replace your bearings.

-- Rodney, Centralia, WA, USA www.etsy.com/shop/ASturdyStick

View seturner's profile

seturner

29 posts in 717 days


#25 posted 08-07-2017 08:32 PM

Note: Embedded video now working

View GR8HUNTER's profile

GR8HUNTER

5683 posts in 1010 days


#26 posted 08-07-2017 10:00 PM

now I have to go check mine …seems like mine takes long to stop ….then when bearing are bad I will say hey wife I need a new saw :<))

-- Tony---- Reinholds,Pa.------ REMEMBER TO ALWAYS HAVE FUN

View sawdustdad's profile

sawdustdad

372 posts in 1182 days


#27 posted 08-07-2017 10:24 PM

My Rockwell Unisaw’s blade stops in 5-6 seconds. 3hp, single phase.

-- Murphy's Carpentry Corollary #3: Half of all boards cut to a specific length will be too short.

View Rarebreed68's profile

Rarebreed68

148 posts in 598 days


#28 posted 08-09-2017 02:08 AM

This post caused me to check mine today. 11.5 seconds from punching the stop button to standstill on a Grizzly single phase 5hp 12”.

-- EARTH FIRST! We'll log the other planets later. Trust your neighbors, but brand your calves. Opinion worth price charged.

View MrUnix's profile

MrUnix

7242 posts in 2496 days


#29 posted 08-09-2017 02:18 AM

I think it will be cheaper to buy a new arbor than buying dies, since one end(away from blade) is reverse threaded fine pitch, and the blade side is right hand threaded coarse pitch.
- seturner

I think it would be even cheaper just to get a thread file… or I’ve even fixed them just chasing the threads using a small triangular file. I can’t imagine you buggered it up beyond repair just banging on it. Next time, put a piece of wood between it and the hammer :)

You might also want to go ahead and swap out the motor bearings as well… if the arbor bearings were toast, the motor bearings are probably not too far behind.

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

View TheFridge's profile

TheFridge

10844 posts in 1783 days


#30 posted 08-09-2017 02:29 AM

Yes. Thread file or or double extra slim taper or needle file with be WAY cheaper. And probably easier to get a file than an arbor.

-- Shooting down the walls of heartache. Bang bang. I am. The warrior.

View GR8HUNTER's profile

GR8HUNTER

5683 posts in 1010 days


#31 posted 08-09-2017 02:43 AM

21 seconds on my walker turner :<))
thats just counting 1 one thousand
should i let it bother me ? :<))

-- Tony---- Reinholds,Pa.------ REMEMBER TO ALWAYS HAVE FUN

View rodneywt1180b's profile

rodneywt1180b

181 posts in 684 days


#32 posted 08-10-2017 09:59 PM

Have you greased it lately? Mine has either 1 or 2 grease ports on the arbor. I cleaned and repacked mine when I bought the saw 8 years ago and generally give them grease about once a year.
Mine takes a bit to spin down too but I’m not in the mood to tear it down to replace them even though I’m pretty sure they’re getting due. I’ll probably try greasing them and see if it helps first. For me it’s far easier to do when I first buy something (play with new toy) than after I get used to using it (PITA maintenance).
I’m not sure of the size needed offhand but I do know Walker Turner used a lot of bearings that are either expensive to get or no longer available I suspect the arbor bearings are some of them.

-- Rodney, Centralia, WA, USA www.etsy.com/shop/ASturdyStick

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