# King 1236ml (Grizzly G4003) Question



## HBilly1022 (Jan 14, 2017)

I've had my King 1236 for 2 months now and I'm working through some issues / setup with it. Today I decided to use the 4 jaw chuck and see it is stamped "Max 1350 RPM". The 3 jaw is stamped max 2145 RPM. According to the decals on the lathe the top speed is 1500 RPM. The Grizzly site indicates the G4003 top speed is 1400 RPM. I am guessing the top speeds for both machines are actually the same but I don't know for sure. 

For you G4003 owners, can anyone tell me what speed their 4 jaw is rated for. Seems odd that the lathe would come with a chuck that can't be used in all speeds.


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## Bob Korves (Jan 14, 2017)

A simple change of the motor pulley diameter will change the speeds, so I do not think you can assume that the two lathes achieve the same speeds.  Also, do you have 60 HZ power there, or 50 HZ?  On my 13x40 lathe the faceplate is limited to 1255 rpm, can't use the 2000 rpm top speed with it, though I have no idea why I would ever want to spin it that fast...  I would certainly want to run a 4 jaw up to 1500 or so, though fairly low RPM  limits are quite common on larger lathes than the ones we are discussing.

I just bought a non contact tachometer direct from China for less than $10 including freight.  It works very nicely and says it is accurate to .1 rpm at speeds from 0.1 rpm up to 999.9 rpm, then accurate to 1 rpm above 1000 rpm.  The rpm range is 2.5 to 99,999 rpm.  You stick a small piece of reflecting tape on what you are measuring, and then point the red LED at the reflector from a 2 to 10 inch distance, and get the results on a 5 digit LCD readout with 0.7" high digits.  Uses a 9 V battery and is simple to use.  Now I know how fast my surface grinder wheel is really turning and how far I can increase the frequency on my VFD while staying below the 3600 maximum speed the wheels are rated to...


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## HBilly1022 (Jan 14, 2017)

I just checked the Grizzly manual and the King manual. They both list all the same speeds for each of the gear combos. The only difference is the decal on my machine, which shows the highest speed at 1500. All the other speeds match the Grizzly and the King manuals. Therefore I suspect the decal is wrong about that one speed and it is actually 1400 RPM. I think I will look into getting one of those little tachs. Would be nice to know for sure what the speeds are.


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## jmanatee (Jan 14, 2017)

Get your self a cheap laser tachometer and check to see
https://www.amazon.com/Digital-Phot...coding=UTF8&psc=1&refRID=R5SW8V34R6FG44W64FHA


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## wawoodman (Jan 14, 2017)

jmanatee said:


> Get your self a cheap laser tachometer and check to see
> https://www.amazon.com/Digital-Phot...coding=UTF8&psc=1&refRID=R5SW8V34R6FG44W64FHA



Great to have. I made a chart with different knob settings on the different pulleys to get a pretty accurate spped chart for my mill with VFD.


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## HBilly1022 (Jan 15, 2017)

Still interested to see if the Grizzly 4 jaw chuck is rated at 1350 RPM. Anyone?


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## jmanatee (Jan 15, 2017)

HBilly1022 said:


> Still interested to see if the Grizzly 4 jaw chuck is rated at 1350 RPM. Anyone?



Where is it stamped?  I can't say I have see it anywhere on it...


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## HBilly1022 (Jan 15, 2017)

It's on the face. If you haven't noticed it before, it probably isn't there.


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## epanzella (Jan 16, 2017)

HBilly1022 said:


> Still interested to see if the Grizzly 4 jaw chuck is rated at 1350 RPM. Anyone?



I just checked the 4 jaw on my 3 year old G4003G. It's right there on the front.    MAX 1350rpm. It's kinda light but I either didn't notice it or forgot about it because it doesn't bother me a bit.


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## HBilly1022 (Jan 16, 2017)

epanzella said:


> I just checked the 4 jaw on my 3 year old G4003G. It's right there on the front.    MAX 1350rpm. It's kinda light but I either didn't notice it or forgot about it because it doesn't bother me a bit.



Thanks so much. Glad to know I'm not special, just one of the boys so to speak.

Have you ever run yours at the lathe max speed, which I believe is 1400 RPM?


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## epanzella (Jan 16, 2017)

HBilly1022 said:


> Thanks so much. Glad to know I'm not special, just one of the boys so to speak.
> 
> Have you ever run yours at the lathe max speed, which I believe is 1400 RPM?



I have run 1400 doing small stuff but I can't say for sure if I ran the 4 jaw to that speed. That chuck is built like a tank, I wouldn't worry about another 50 rpm particularly after the sent it with the lathe.


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## HBilly1022 (Jan 16, 2017)

epanzella said:


> I have run 1400 doing small stuff but I can't say for sure if I ran the 4 jaw to that speed. That chuck is built like a tank, I wouldn't worry about another 50 rpm particularly after the sent it with the lathe.



I agree. The only difference is that my lathe shows a max speed of 1500 RPM, not 1400 as noted on yours. I am positive both lathes actually spin at the same max speed, since all the other gear combos have identical speeds. I'm going to get a tach for mine just to make sure but knowing that the Grizzlys are shipped with the same 4 jaw, I am no longer concerned about it.


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