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Rif
03-26-2007, 01:02 PM
Hello,

I still haven't bought my bigger lathe yet because my stupid mobile home hasn't sold yet; :mad: :mad: :mad: but, I have some questions to pose to the group anyhow.

Bear in mind, however, that I am not going to re-hash the old belt vs gear head argument nor the D1-4 cam vs threaded spindle argument so please ignore those differences.

Anyhow, I am eventually considering buying a lathe similar to either one of the following:

http://www.grizzly.com/products/G9249
http://www.grizzly.com/products/G4003
http://www.grizzly.com/products/G4016 (probably the Birmingham variety)
http://www.southern-tool.com/store/gmc_gml-1440bg_bench_lathe.html

I have also made the observation that some companies have similar products; but, make cost saving changes like skimping on the motor sizes. For example wttool has a lathe almost identical to the G9249; but, they sell it with a 1HP motor.

Now, for my questions:

1. It appears that the G9249 has a compound that is different from the G4003 and G4016. I noticed that the G9249 has a compound similar to that of the largest lathes. (i.e. G9733) Is one compound more rigid than the other? Is any compound simply better than the other for a reason that I am not aware of? I bring this up do the rigidity issues people have posted about the 9x19 series lathes.

2. Looking over the specifications for all of the above listed lathes, and larger lathes (i.e. G0554) I noticed that the bed widths are the same and the weights are very close for all of the lathes that I have listed. This makes me suspicious that the larger of the above listed lathes (the GMC 14x40) would be more like a 12x40 on risers. Is this a valid observation?

Thanks in advance,

Brian

SGW
03-26-2007, 01:20 PM
One observation: the G9249 has a 50 rpm low speed, significantly lower than any of the others, which I think you might find handy on occasion.

lynnl
03-26-2007, 03:13 PM
Looking at the picture of the G4016 (and 4003 too) I see three rods along the front. The leadscrew at the top, the feed rod below that, and then a third one at the bottom, which does not appear to go through the apron.

What is that bottom rod? Is that a clutch?

Bguns
03-26-2007, 03:40 PM
Bottom Rod is Apron mounted Fwd Rev Stop handle, switch is close to headstock...

eperkins
03-26-2007, 03:52 PM
Rif;

I recently looked over all the Grizzely offerings when I got the new catalog and my vote goes for the belt driven 12X37 which is the G9249. Belts are a lot simpler and quieter than gears. There is simply less to go wrong and the lathe is more forgiving if you crash. The clincher though is the low end speed. Since it is a true back geared screwcutting lathe, the low end is about 50 rpm which is what you want for screwcutting (just like my South Bend Heavy 10). I don't remember the low end speeds on the gearheads, but I do remember all of them looked too fast for my tastes. Good luck with your choice!

Perk in Cincinnati

lynnl
03-26-2007, 03:53 PM
Thanks Bguns.

J Tiers
03-26-2007, 05:12 PM
I will second ("third"?) the comments on low end speed in the 30 to 50 rpm area.

if you thread any coarse threads of larger diameter, you will want it.

Heck, if you TURN maximum diameter pieces you may very well want it.

sch
03-26-2007, 06:57 PM
Gear drive lathes are noticeably noisier above 4-500 rpm spindle speed.
The low end speeds on all the lathes are not appreciably different, though
78 rpm is a bit faster than 50 rpm. The 4016 does have a significantly
faster high end at 2100 rpm than the other two lathes which top out at
1200-1400 rpm, may be useful if you anticipate a lot of work in aluminum
at sub 1" diameters and use of carbide tooling. OTOH the placement of the
controls of the 4016 is not exactly user friendly, but most people will
instinctively go for the apron lever in a pinch rather than the Estop.
The 4003 appears to be sans cabinet, an extra cost item at least $300 with shipping. OTOH you get a QC tool post with the 4003, an at least $90 item for the other lathes. The tool posts for the other two will be quickly discarded in actual use as you tire of fiddling with shims. Ergonomics of speed changing and thread cutting gear changes is hard to judge from the pix. The SB 12-36 I used at school had a very smooth speed change, the
roughly 4003 I use at home (not Grizz sourced but another) needs to be wrestled with a bit to change the speeds. Not really a problem as speed
changing is only done occasionally after one chucks up a piece.

MickeyD
03-26-2007, 07:15 PM
Get the biggest lathe that you have room for. I started out with a 9x20 years ago and now have a 15x50. The bigger machines are a lot stiffer and make things like parting a joy, and are generally make you look a lot better than you really are. Don't discount the used market, I see a lot of nice older machines go for what you are looking at spending, plus if you don't crash them they have already depreciated all that they will.

Rif
03-27-2007, 10:29 AM
One observation: the G9249 has a 50 rpm low speed, significantly lower than any of the others, which I think you might find handy on occasion.


I am seriously looking at the G9249 primarily due to the low-end speed. If the compound is better on the G9249 than on the G4003, then it is a clear winner as far as I am concerned. The G9249 also comes with a 2HP motor, while the G4003 has a 1.5HP motor.

But, I can get the GMC 14x40 for only a little more when you consider the shipping and tax on the G9249.

The GMC has module and diametric threads, as well. My concern with the GMC is that it seems like it may not be as rigid due to it appearing that it is a 12x lathe with a higher headstock. Additionally, I may not need the module and diametric threading capability. Given that the G9249 has 50 standard thread types it may be able to cut some module and/or diametric threads anyhow....I am not sure. It may be possible to make or use different change gears to "add" this capability...if required.

Since I have to get the lathe in my basement, I don't want to exceed slightly over 1,000 pounds. Also, I don't want to go over $3,000. (Yes, I know. If I can find one, I can get something American for less. Where I live there isn't too much available...I would also have to figure out how to get it home.)

The G4016 is interesting, as well; but it may be a little less rigid and the compound appears to be the same as the G4003. However, it has a better speed range than the G4003 (I think of the G4003 more as a 7 speed lathe due to the RPM spacing.) The G4016 also comes with a 2HP motor. Both gear heads have a higher low RPM.

Thanks,

Brian

Rif
03-27-2007, 10:49 AM
Gear drive lathes are noticeably noisier above 4-500 rpm spindle speed.
The low end speeds on all the lathes are not appreciably different, though
78 rpm is a bit faster than 50 rpm. The 4016 does have a significantly
faster high end at 2100 rpm than the other two lathes which top out at
1200-1400 rpm, may be useful if you anticipate a lot of work in aluminum
at sub 1" diameters and use of carbide tooling. OTOH the placement of the
controls of the 4016 is not exactly user friendly, but most people will
instinctively go for the apron lever in a pinch rather than the Estop.
The 4003 appears to be sans cabinet, an extra cost item at least $300 with shipping. OTOH you get a QC tool post with the 4003, an at least $90 item for the other lathes. The tool posts for the other two will be quickly discarded in actual use as you tire of fiddling with shims. Ergonomics of speed changing and thread cutting gear changes is hard to judge from the pix. The SB 12-36 I used at school had a very smooth speed change, the
roughly 4003 I use at home (not Grizz sourced but another) needs to be wrestled with a bit to change the speeds. Not really a problem as speed
changing is only done occasionally after one chucks up a piece.


Hello,

I have found that most of my work is with steel and it takes forever to work on with my little 3x17 Sherline. I can, at best, make 0.005 cuts in steel and 0.010 cuts in aluminum on this lathe. But, if I have anything really small in aluminum or brass, I'll just use it instead so I am not too concerned about the high top end speeds.

I was wondering who came up with the idea of placing the e-stop at the top rear of the headstock on the G4016. If you really need to hit that button, reaching across a rotating chuck probably isn't something you have in mind. :eek:

I don't even know if I need the cabinet. My basement was dug-out at some time in the past, and, as a result, I have 2 foot ledges projecting from the walls. These ledges are a little over 2 feet in height and it may work better to just pour a little more concrete to raise a lathe up to the correct height. That would definately make for a nice, rigid, mounting surface.

Thanks,

Brian

Bguns
03-27-2007, 02:00 PM
My G4003 spins 70, which I thought would be too fast, but after cutting a 3 in diameter by 8 TPI thread in 4140 and getting a very smooth thread. I am satisfied.... I might, (someday) pull 1 phase and put in a 3 phase with VFD and have even slower speed if needed, along with smoother power to lathe. I change speeds about 10 times per job. Most lathes do not have syncronizers SP ?, so small rotation of spindle to jog gears in line is the standard thing to do, I see many people that just can't get the hang of the fact that gears must be aligned to mesh.... I can leave my mike, calipers, rule,
centerdrill, next drill bit, and other stuff on top of spindle housing without having to lift cover to change speed. My old South Bend 9 does not get much use any more, parting at 200 rpm without fear of snapping crunching sounds is fun.... A simple pully/belt change will drop speeds, if you must go slower. Don't let the 70 RPM be a deal killer on that style 12 by 36....

pcarpenter
03-27-2007, 02:59 PM
I have a Kent KLS 1340A which is the same as the Grizzly G9036 in different colors and a lot lower price tag. It appears *very* similar to the 14x40 that you posted.

http://www.grizzly.com/products/g9036

Low end spindle RPM on this is 70 and I wrung my hands over this for a long time until I bought the lathe and have not had any issues with it at all. For most threading, I end up running it at the 115RPM speed than the slowest speed anyway, producing a better finish and it still doesn't get away from you. 70 RPM is still there when turning below say 10 TPI.

Rated motor horsepower is unfortunately subject to exaggeration anyway nowdays, so an honest assessment of one model may make it look inferior to another...whether it is true or not.

As for gear noise, I think that too often is one of the generalities that gets repeated until it gains a life of its own. I have a mini-mill with a geared head with no oil bath and it is just plain annoying. This lathe, on the other hand has an oil bath for both the head gears and feed gears, and its really fairly quiet--quieter than the G4003's they have here at work which has an open feed gear train. One key is to not drive the feed gears when you are not using them.

I find more noise from the whirling chuck and the end gear train (which you also have with a belt drive lathe) than from the bathed gears that replace a belt. Gear driven lathes offer no belts to handle with oily hands etc, but do not offer any fudge factor if you crash something. The answer to that is not to leave it unattended....and the foot brake (panic stop) helps put an end to crashes too. I like the comfort that comes from the use of a foot brake. I parted the center out of a large disk brake rotor with my nerves on edge as it let go, but it really was no problem catching the part while the other foot stopped the lathe. Anyhow, its a feature worth having in my opinion. I don't use it all the time to avoid wear, but its there when you do need it. It disconnects power to the motor and will stop the spindle NOW!

The bed on this lathe is a bit bigger than the G4003, but not on par with the 14x40 Clausing knockoffs that are so popular (Enco still sells them as I recall). That's a pretty nice lathe. Another shop here at the U has one and it has a solid cast iron base and weighs about 500# more than the 14x40 you have pictured (which is very similar to my lathe) and has wider bed ways. It is, however a bit low to the ground in my opinion. The lower center of gravity is good, but stooping over it is not.

good luck with your decision
Paul