# Grizzly G4003 versus G4003G



## Bill_729 (Feb 8, 2019)

This is my first post here.  I read somewhere that it is acceptable to ask "dumb questions" here so, please, let me please get those out of the way first.   I have been trying to compare lathes lately, and I was trying to compare allowable feed rates. That resulted in my question:

1. Does the quick change gear box drive both the feed screw and the lead screw to push the carriage at the same rate along the longitudinal axis, when it is set at a given setting?  My interest in this question is that I want to know is the extent of feed rates that are available.  On a comparable PM machine with 12" swing, it appeared there were about 6 rates available, with the smallest being about .002"/rev.  This makes me think that the answer to my question is likely"no", and thus I don't know the feed rates that are available on the G4003.  If the answer is yes, than the feed rates correspond to the thread capabilities, which range from less than .001"/rev to .031"/rev. or so.  I was thinking if would be advantageous to have the smaller feed rate available (less than .002/rev.).  I'm a "newbie", What does the voice of experience say?

Incidentally, I used a lathe in high school, where I happily took all of the shop classes. I may have used a Jet 1240P lathe at that time (because they look familiar).  Since then, and in the last month or two I have watched about 200 videos by MrPete222 and ThisOldTony, et. al.   Okay, next question.

2. From the title of this message, I have obviously been drawn to looking at the G4003.  Then I noticed, just on the next page of the catalog, that after you toss in the stand, and separate shipping, that the G4003G comes in perhaps at an even (slightly) better price. The G4003 has a D1-4 spindle and a smaller bore than the G4003G which has a D1-5 spindle.  I don't have an interest in making guns (and I know that the G4003G seems to be targeted (a little pun there) toward gun-makers).  What do you make of this-and/or which would you choose?  

3. Am I likely to find a Clausing lathe (1300/1301 or other) which runs on single phase 220v (which I have available)?  I've gotta say, I find some of the older lathes, like ones named "Colchester", to be handsome machines. FWIW, I can tell you for sure that my wife doesn't (see it).  : )

Thank you for any kind guidance and assistance that you can offer me.

Bill_729


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## Tozguy (Feb 9, 2019)

Welcome aboard!
If you want/need the extra features of the G model then make your choice accordingly.
Forget the gunsmithing angle. The extra features of the G model can be handy in many other ways.

Just a caution that the D1-4 spindle might be a little more common and easier to find chucks and backplates for.

Other than that I would get as many feed rates as possible. To see what is available on the 4003s go to the Grizzly website and check out their manuals (which are excellent).

I do not have a preference for PM or Grizzly but do endorse your efforts to fully understand and anticipate how to use a lathe before you commit.


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## jwmay (Feb 9, 2019)

1: I've got a G4002, which is a shorter version of the G4003.  I use the same gearbox to change the ratio of spindle rpm to leadscrew, and spindle 

rpm to feed rod.  But there are two charts: One for threading, and one for power feed.   I didn't even know about the feeds chart until I saw a 

picture of someone else's on the forum and noticed their chart, which prompted me to check the same spot on my machine.  I've had the machine for two years.  So with that admission, my experience/intelligence level should probably be questioned. ha!  Anyhow, the specs are as follows:

Number of Longitudinal Feeds....................................................................................................................... 40 
Range of Longitudinal Feeds........................................................................................ 0.0011 – 0.0310 in./rev. 
Number of Cross Feeds................................................................................................................................. 40 
Range of Cross Feeds................................................................................................... 0.0004 – 0.0105 in./rev 
Number of Inch Threads................................................................................................................................. 40 
Range of Inch Threads.................................................................................................................... 4 – 112 TPI 
Number of Metric Threads.............................................................................................................................. 29 
Range of Metric Threads............................................................................................................... 0.2 – 4.5 mm 

2: The gunsmithing model, in my very unqualified opinion, is an upsell that most won't need.  My personal experience tells me that my shorter, 

smaller G4002 is more machine than I need.  And I often wish I'd have gotten something even smaller, just because it's kind of a big deal to move 

something that weighs a thousand pounds for me.  But, who knows...maybe I'd appreciate some features of the G4003G.  If my luck holds, I'll never 

need to find out.

3: I don't know.  I don't even know what a Clausing 1300 is, sadly. But don't let the electrical stop you from getting what you really want.  These guys on this forum can walk you through just about anything.  Many of them have machines meant to run on 230 Volt three phase, using some electrical wizardry called a VFD.  Evidently, it'll solve almost any mismatch problem you might encounter.  Assuming your comfortable doing electrical work.  

Welcome aboard! You are the first person I've seen on here within a few hours of me.  That's a little uplifting in a way. Maybe someday there'll be enough to have a group.  Professional machinists around here aren't really all that interested in explaining how they would do a particular job.  They all get this angry look on their face, and start speaking in grunts and hand signals when you try to pick their brains. Anyhow, let me know if I can be of assistance.  I may not know how to do something, but I can usually find someone who does.


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## Mutt (Feb 9, 2019)

I have owned a 4003 since new in 1999. If given the opportunity to buy the same lathe again, the answer would definately  be NO. Grizzly's customer service STINKS. Their techs are not knowledgeable  and have the "I understand"mentality, but will readily sell you a part that will not fit, without serious modification. If ya wait to order replacement parts for more than 8 years, you'll be totally out of luck, stuck with who knows how much research trying to locate anything that "might" work and be forced to make that non-stock different part work. (if ya ever want to use the lathe again. Did I mention their customer service STINKS?


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## mksj (Feb 9, 2019)

Not sure which PM model you are using for comparison, but looking at a similar type you would be looking at the PM-1236GT which has the same Norton style open gearbox. Both the G400X versions and the PM1236/1340GT will do the same threads and have similar feed rates that you would typically use, 0.01-.002"/rpm (although the available range is 0.082-0.0027"/rpm). Feed and leadscrew are different, one is for feed which you would primarily be using the D and E range of gears, and for threading the full range depending on the desired thread pitch.



The G4003G had a D1-5 chuck mount, not a big deal to get a backplate for that size, but you are still limited by the spindle bore on these models which are ~1.57" (40 mm). The G4003 has a smaller spindle bore of 1.417". The D1-4 is a very common chuck mount, so preferable.

As far as single phase vs. 3 phase, on the lathe you will get a better finish with 3 phase because of the more even motor pulses, VFD conversion is not so difficult, but it does add to the cost. In my book well worth the investment. Another benefit of the VFD is quick braking if you do not have a foot brake which all these models are lacking. I have previously outlined the basic VFD conversion for the 1236/1340GT, so you can review that if you want to go 3 phase.









						Pm1340gt Lathe Basic Vfd Control Conversion Using The Stock Control Board And Switches
					

I'm new to working with a lathe, but having to rotate the chuck to find the key most every time I stop seems to be an inefficiency that could be resolved. Most chucks have either 2 or 3 key chuck pinions, so really not an issue. The chuck rotates easily or bump with the jog. Probably one of the...




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Due to the tariff's being imposed the pricing of the Chinese mainland machinery has gone up, making the price difference between similar models to those made in Taiwan much closer. The fit and finish of the comparable  Taiwanese machinery of similar models is better.  I would suggest you look at the PM-1236GT which is a higher quality lathe compared to the G4003/g and priced in the same range. If you are new to machining/lathe I would suggest buying new, as availability/the price difference of a "good" used lathe has gone up. You also do not need to deal with limited or no replacement part availability for older lathes.


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## hman (Feb 9, 2019)

Bill_729 said:


> This is my first post here.  I read somewhere that it is acceptable to ask "dumb questions" here so, please, let me please get those out of the way first


Sorry, but you can't ask a "dumb question" here.  That's because there ain't no such thing! 



Bill_729 said:


> 1. Does the quick change gear box drive both the feed screw and the lead screw to push the carriage at the same rate along the longitudinal axis, when it is set at a given setting?  My interest in this question is that I want to know is the extent of feed rates that are available.  On a comparable PM machine with 12" swing, it appeared there were about 6 rates available, with the smallest being about .002"/rev.  This makes me think that the answer to my question is likely"no", and thus I don't know the feed rates that are available on the G4003.  If the answer is yes, than the feed rates correspond to the thread capabilities, which range from less than .001"/rev to .031"/rev. or so.  I was thinking if would be advantageous to have the smaller feed rate available (less than .002/rev.).  I'm a "newbie", What does the voice of experience say?


I'm not sure if I'm answering what you asked, but here goes ... the gear box turns both the feed screw and lead screw (on lathes that have both) at the same RPM.  When the half-nuts on the carriage are clamped to the leadscrew for threading, the carriage moves at a precisely controlled rate, so that the threads are precise.  

When the feed screw is engaged, it drives a gear train inside the carriage, which eventually meshes with a gear rack along the underside of the ways.  This is generally a slower feed rate than you would get with the leadscrew (though not quite as precise), and used to get an even finish along the length of the workpiece.  Some lathes can also connect the cross slide to the feed screw, to get a good finish on the face of a workpiece.


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## Mitch Alsup (Feb 9, 2019)

The feed rate on the leadscrew are not the same as the feed rates on the feed rod.

The G4003G is supposed to have better bearings in the spindle.
The G4003G spindle has a bit more bore than the G4003 spindle.
The G4003G comes with QCTP


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## Bill_729 (Feb 9, 2019)

Thank you for all of the replies to my questions.  You can be sure that I read them all thoroughly and more than once!   In reviewing manuals at PM ("Precision Matthews") and G ("Grizzly"), I noticed that PM was careful to detail  "Carriage Drive, turning" and "Carriage Drive, threading" separately.  G listed the Carriage drive rate ONLY with regard to threading.  On the PM 1236 lathe, the Carriage drive for turning is listed as .002" to .048".  I observed that on the PM 1340, the lower figure goes up to .0027, which makes some sense as the lathe has 13" swing.  The PM 1236 has some nice additional features (1800 top spindle rpm compared to 1400, micro carriage stop and clutch, coolent system, 5 holders for the tool post), at close to the same price as the G4003-G.   I think all of the lathes considered here come with QCTP.  Grizzly give you _one_ tool holder.  I'm thinking they give you a QCTP, and make it back selling you tool holders!   : )

That brings up a newbe question: Are tool holders generic, or once you have a QTCP do you have to go to the source for the tool holders?

Some of these lathes seems to be rather "standardized".  Do many Grizzly parts fit on a PM lathe and vice-versa?  I did read that PM only sells parts for machines they sell, but that's a different matter.  No doubt I need to create a list of _everything_ that I will need to get started machining metal.  It will have to share a 500 square foot area partially filled with machines which machine wood.  I read somewhere on this forum about using a bbq grill cover over the lathe when not in use (to protect it from dust), and it is my intention to do the same.

Bill_729


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## Aaron_W (Feb 9, 2019)

Bill_729 said:


> That brings up a newbe question: Are tool holders generic, or once you have a QTCP do you have to go to the source for the tool holders?
> 
> Some of these lathes seems to be rather "standardized".  Do many Grizzly parts fit on a PM lathe and vice-versa?  I did read that PM only sells parts for machines they sell, but that's a different matter.  No doubt I need to create a list of _everything_ that I will need to get started machining metal.  It will have to share a 500 square foot area partially filled with machines which machine wood.  I read somewhere on this forum about using a bbq grill cover over the lathe when not in use (to protect it from dust), and it is my intention to do the same.
> 
> Bill_729



QCTP's are sized  (OXA, AXA, BXA etc) and can be wedge type or piston type but at least in theory an AXA tool holder "should" fit any AXA tool post.



As far as parts fitting between different import lathes, I'm sure there are cases where this may be true. Many are built in the same factory and only differ in quality control, how they are optioned, and paint color as specified. This is certainly the case for many of the 7 and 8" mini-lathes, but even then there are some differences as vendors may spec different motors or other features. An import lathe marketed to the US may have an SAE lead screw vs metric, and of course electrical components may be different to suit the home market (standard electrical current varies around the world).

Another poster was asking about their Weiss 10x30 lathe. This appears to be essentially the same lathe as the 10x lathes Grizzly and PM sell, but each company uses a different method for securing the chuck to the spindle. 


The larger lathes seem to be even more varied, and I would think parts commonality would be even less likely between Taiwan made lathes (some PM, and Jet) and Chinese made lathes (Grizzly, HF, some Jet) even if the look similar.  

Short answer, maybe, but don't count on it.


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## pdentrem (Feb 9, 2019)

BBQ or motorcycle cover will work to keep the wood dust off the machine.


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## hman (Feb 9, 2019)

Bill_729 said:


> Some of these lathes seems to be rather "standardized".  Do many Grizzly parts fit on a PM lathe and vice-versa?  I did read that PM only sells parts for machines they sell, but that's a different matter


OK, reiterating what Aaron_W said, it's pretty well known that numerous tools come from the same factory (factories), and are re-badged by the sellers.   But each retailer can specify the various features they want.  I think I read somewhere that PM and Griz buy from different factories ... but don't take this as a given.  

If you're going between brands/sellers, the parts situation is pretty much a crap shoot.  You can sometimes get an idea about whether something will interchange by carefully studying the parts diagrams for both machines, looking for similarities/differences in the details.  But often, the diagrams look almost hand drawn, and so the critical details might be lacking.  You can download Grizzly manuals and parts breakdowns from their website, and I think you can do so from PM's website - could be educational!

Finally, as Mutt said in post #4, even the buying parts from the same retailer where you got the original tool isn't a guarantee of success - features and designs change over time.


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## Splat (Feb 11, 2019)

Go new. Unless you can wait and realistically set a time-frame to allow searching for a nice used lathe...otherwise you'll just keep waiting..and waiting...and not getting a lathe! Also, unless you feel you have the knowledge or have an experienced friend that will know what to look for in a used lathe it's very easy to get taken. I have a G4003g and haven't had any problems except the motor died but that gave me an excuse to go the VFD way.   I've also dealt with Grizzly's customer service for other Grizzly items I have and never had a problem with them. I would compare prices and what you get between Grizzly and Precision Matthews's machines. I would not hesitate to go with a PM machine even though I've never bought anything from them. I've heard enough from others to know they're good guys who sell good machines at decent prices. We've all gotta make a buck but it's the after-sale support that goes a long way. I don't think you could go wrong with either brand.


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## Bill_729 (Feb 12, 2019)

Splat said:


> I have a G4003g and haven't had any problems except the motor died but that gave me an excuse to go the VFD way.



I'm glad you like the machine.  Does your comment mean you are running a 3-phase motor now?

Bill


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## Splat (Feb 12, 2019)

Bill_729 said:


> I'm glad you like the machine.  Does your comment mean you are running a 3-phase motor now?



Yes, I'm running a 3 phase 220v motor from a 1 phase 220v outlet via the VFD. Also, using a Machtach gives me RPM or SFM and I love it.


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## epanzella (Feb 13, 2019)

I have the G4003G for 6 years. Luv the machine and highly recommend it. The thread feeds go thru the GC gearbox and then are driven by the half nuts and leadscrew thread. The power feed ratios are different because they go thru the QC gearbox and then go thru gearing in the apron. The G model will feed as slow as .001/rev and will cut threads from 4 tp 112 tpi without gear changes. There are a few gear changes required for metric threading. The bore of the G4003G is 1.57" and since barrels and junkyard stock are so common in 1.5" OD,  being able to pass that thru the headstock is a gamechanger. Th D1-5 spindle is also more rigid than the D1-4 on the non-G model. The bearings on the G4003G are higher quality and the outboard spider is really a necessity for long stock.  Good luck in your quest!


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## Bill_729 (Feb 14, 2019)

epanzella said:


> The G model will feed as slow as .001/rev



Tubalcain (of YouTube fame) indicates that is desirable. He even points out that the SB Heavy 10 went down to .00076"/rev.  (I could be off by a little numerically, but not in spirit).  He had a lot of praise for that, explaining that you can get some very nice finishes.  IIRC, his Craftsman Atlas only went down to .004"/rev., and his only explanation was that the designers "must have never used a lathe"...  He rigged up his own feeding system for feeding it by motor from the tail end.  I am glad to hear that you like the machine!

Bill_729


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## Bill_729 (Feb 23, 2019)

I have a few questions about the PM1236.   I see that it is available with a "carriage stop and clutch".
Although I have seen a carriage stop which disengages the carriage feed, this does not seem to be the norm (I think).

1. Is it's use intended to support (the routine operation of) turning up to a shoulder with the feed screw?
If I understand correctly, on "most" (other small) lathes, you would feed the cutter to the shoulder by hand, using a carriage stop as more of a guide. 

2.  I've noticed that some people are doing DRO "on a budget" (significantly less than $450-$600).  Same accuracy?  Please don't write out a long answer to this because, as a hobbyist, I don't have an additional $600 for it right now, but I would be curious in whether you would advise me to try to add it on a budget.

3. I see a base which is 200# heavier is available for an additional $250.  What factors would indicate  whether this is a smart investment?''  Turning heavy asymmetrical work seems like one answer. Anything else?  To be honest, I'm leaning towards it since I've always heard "heavy=good", but I like to understand the "why's" behind things.  I can add a DRO anytime, but I have one chance to choose the base.

4. If you didn't buy the leveling feet (for $160), how would you level the machine?  I assume you would level the base before you put a lathe on it (with an engine hoist), but then you would need to "fine tune" it, right?  Do you basically need to bring out an engine hoist every time you wish to do so (to shim it)?  At this point, I have neither a machinist level nor an engine hoist (where is my HF 25% off coupon?), but they are in the category of "planned expenses".

I hate to bother you with so many questions, but I figured it would be better to "get them all out there" all at once! Thank you!

Bill_729


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## mksj (Feb 23, 2019)

I routinely do not use the carriage stop clutch as a hard stop for feeding, always been worried about the stop actually moving if hit hard. It needs to be tightened down securely. Still I use it as a safety backup when feeding close to a chuck or hard face.

Budget DRO's with glass scales in the $200-250 range work just as well and accurate (within specs) as those costing much more. You give up some things like support/warranty, a clear manual, better (functional) designed keypad/display, reliability and to some degree the seals on the scales (they tend to be poorer material single lip as opposed to double lip). But can vary significantly between low cost DRO's. If on a budget, they will do just fine and well worth the nominal expense.

On the base, I assume you are talking about sheet metal vs. cast iron base. Cast iron has very good vibration dampening properties and the added weight will provide increased rigidity/dampening. Yes, I would go with the cast iron base hands down, a good investment.

You need solid leveling feet to adjust out any bed twist, you also need a precision level to dial it in.  The S & W  leveling mount) feet you should be able to pick up for $8-15 each,  most use 1/2" so BSW-2, BSW-2A if taller thread. Zoro routinely has 15-25% discount coupons/notices.

This eBay one is only worth considering if they combine shipping.
https://www.ebay.com/itm/NEW-S-W-BSW-2N-Leveling-Mount-1-2-13-J6T/172191197060








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You can purchase a precision level for around $75








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You are not bothering people by asking these questions, we all start out at the same place and gain knowledge as we go forward. If one thinks they know it all, then they are misguided, as the more you learn the more you realize the less you know.


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## Bill_729 (Mar 28, 2019)

Is the PM-1236 lathe made in Taiwan, or do you have to step up a notch for that "feature"?

Thanks,
Bill


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## Aaron_W (Mar 28, 2019)

My understanding is the Taiwan built PM machines end in a T, so the PM-1236 is made in China, the PM-1236-T Ultra Precision is made in Taiwan. 

The 1236-T does include a few tangible differences beyond country of manufacture, slightly larger spindle bore (1-9/16" vs 1'1/2") and available with a 3 phase motor, probably others as well, but those were 2 that caught my eye.


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## Bill_729 (Mar 28, 2019)

Arron, Thank you for the information you shared.  I'll investigate further!

Bill


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