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Anyone own a GH1440W lathe from Modern Tools or a PM1440HD from Precision Matthews?

John Conroy

member
Premium Member
I'm considering purchasing a new lathe before I retire in June and this one is on my short list. I think someone on the forum must own on these machines, the Modern Tools version and the PM one are very similar. I'd like to hear your impressions if you have one. This machine is also sold by Jet as model GH1440W. I don't really have a good reason to buy a new lathe other than this will be my last opportunity to buy NEW.

Modern Tools GH1440W.jpg

pm1440hd.jpg

Jet GH1440W lathe.jpg
 
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DPittman

Ultra Member
Premium Member
Ooo those all look nice. Congratulations on the upcoming retirement and your retirement gift to yourself LOL. That sounds like a great way to start your retirement!
 

John Conroy

member
Premium Member
Well since my CanTek lathe is sold I now have a hole in my shop where a lathe should be. I sent Dahl at Modern a bunch of money and they are going to deliver a new GH1440W to my garage next week. As they say, you only live once.
 

DPittman

Ultra Member
Premium Member
Just interested in the main reason you upgraded your lathe? Features or size or just new retirement gift?
 

John Conroy

member
Premium Member
Well I think I would put the order like this. Retirement gift (last chance for a major purchase before the regular paychecks stop). Next the weight is more than double that of my old lathe and it's a much more solid machine. When I upsized my mill with one that weighed three times as much I was much happier with it's performance.Third, it has features like a footbrake that couldn't be retofitted to my old lathe plus a DRO, and it's brand new. I hope I enjoy it as much as I think I will. Two more weeks until my work schedule will allow me to have it delivered to my garage. Being without a lathe for that long is tough!
 

PeterT

Ultra Member
Premium Member
And a taper attachment and wider selection of speeds & feeds and wider bed and higher wattage motor and a beefier tail stock and I think flood coolant?... There is a lot to like in this package.
Sadly the only thing its lacking is the J.C. "Zamboni oiler bar upgrade" so he will have to make due with their standard lube bath LOL
I hope the move goes smooth & look forward to the post honeymoon report.
 

John Conroy

member
Premium Member
Thanks Peter, you're right. I was being lazy and didnt feel like typing all my reasons but its 3 am and I can't sleep so here goes. I'm looking forward to learning how to use the taper attachment which will be fun. The extra rigidity that comes with a 10 inch wide bed (instead of 7") will be cool. That extra width and the added mass of the tailstock will be welcome.
Plus there will be no need for the "Zamboni oiler" (lol) system because the GH1440W has a fully enclosed feed and threading gearbox instead of the Norton style gearbox on my old machine.
The fact that it's made in mainland China was off-putting at first but after close examination the quality appears to be at least as good as my 1999 Taiwanese lathe.
Peter and I looked at some "built in Taiwan" new lathes at Modern on our visit and they are still many times nicer in the fit and finish then the mainland made machines. The Taiwan built lathe we looked at with Meehanite castings was a thing of beauty. The castings are so smooth there is no need for filler before painting. There are 2 big reasons I'm not buying a Taiwan built lathe though. Modern doesn't carry any in the size suitable for me, and the price if roughly double for a similar sized Taiwanese lathe compared to a mainland China built one. Size does matter too! I was looking hard at the C6241 16" by 40" lathe (so was dabbler) but it had a 7.5hp 3 phase motor and powering it would have added a lot of money and hassle. The C6241 is a beauty and is only about $1000 more than the GH1440W but I was quoted $4000 to $5000 by 2 different sources to install a VFD. I know i could do it myself but bare minimum cost would probably be $2500. That and the fact that my electrical panel in my house is already full was a deal breaker. The GH1440W has a 3hp (the old lathe was 1.5hp) single phase motor and will run on the current electical service in my garage. Big picture is that I don't need something with a D1-6 spindle, the weight of the chucks would require some sort of hoist to change them. The GH1440W has a D1-4 spindle so my existing chucks wil fit as well as all my BXA tooling for the quick change toolpost. To change over from the 5/8" tooling to 1" would be expensive. A larger spindle bore (both my old lathe and the new one are 1.5") would be nice but that would come with a D1-5 or 6 spindle that I don't really want.
I put a lot of thought into the purchase before made it and there were compromises made but I think I made the best choice for me.
 

Dabbler

ersatz engineer
Your thinking process is very similar to mine.

The 16X40 comes with a CXA tool post, for which the holders are very very spendy. That being said, I have several 2HP and 3HP 3 phase motors that I can swap to and use my existing VFD on (Yes I move my VDF- I'm too cheap to buy more than one!)

For me the decision is moot: I'd have to look for another contract to afford the purchase, and I just bought a used C636 - which should do me fine once it gets going... ( I also have access to a 15X60 and an 18X60 any time I need it if the 636 is too small for the work)...

FYI: Dal quoted me 5K uplift from the 1440 to the 1640 - he was giving you a deal!
 

John Conroy

member
Premium Member
Well the GH1440 will be here next week and I've been getting my garage ready for it. I needed to upgrade the electrical service. The old lathe was 1.5hp and the new one is 3hp, both single phase. I was powering the old lathe with a #12 awg extension cord from the 40 amp plug I installed to power my welder. To bring everything up to code and to meet the electrical specs given to me by Modern's electrical technician, I installed a new box to house the welders plug and from there I ran new #10awg wire through metal conduit to 2 new 20 amp plugs. One plug for the lathe and another for the mill. I have a new male plug ready to install on the new lathe so I can get it running quickly when it arrives at it's new home. I'll be sure to take pictures of the unloading process when it arrives.
20190223_120504.jpg 20190223_120217.jpg 20190223_121428.jpg
 

PeterT

Ultra Member
Premium Member
Looks good. Just curious, what did the official FLA (full load amps) and peak/starting amp spec work out to on the GH1440 motor?
 

PeterT

Ultra Member
Premium Member
Potential prep consideration. I suspect it will be delivered with short cord coming out of the CSA box which Modern installs to make it compliant, no plug. On my (15A) lathe & mill, I just stripped the leads back & connected to plug pins using the typical 3 wire hold-down screws. That style of plug separates so you can do that.

But what I didn't contemplate on my 40A 935 mill is many of those big amp residential oven range type plugs are sold as an all-in-one sealed plug with integral wire extension harness. The plug itself doesn't come apart to allow re-wiring like that. So we removed the modern harness & tied the plug harness wires into the CSA box terminals. Thank God for Dabbler. Not sure if all these big amp industrial plugs are like this or just the one we selected.

Now I'm curious, what do you guys do on welders when you have to integrate your particular plug standard. Do you make a 'cord connection' or tie it into the welder terminals or?
 

John Conroy

member
Premium Member
Unfortunately no actual current numbers were given. This is the information Jamie sent me.

"Use #10 cabtire/tech cable.
Upsize it to 20Amps breaker.
This is due to high inrush current of single phase motor.

It is customer’s choice to hard wire or use a plug because of remote location or permanent spot of the machine.

I would prefer plug type male and female (wall mount) ... in case of future changes "


I did my own research and found generic current specs for single phase motors. Recommended breaker size listed as 25 amps and full load current listed as 17 amps.
The recommended wire size given is #12awg but to be safe I went with 10.

I found it quite annoying that Jamie couldn't be bothered to give me all the info I asked for but I'm not going to make a big deal of it.

I'll measure the start up current when I get it running
 

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kevin.decelles

Jack of all trades -- Master of none
Premium Member
The lathe I had delivered (14x40 but the step down from John's) from Modern in March came exactly as Peter described, cord with no plug end. I had 220v 15amp plugs on both sides of the shop, so wired it for that plug. It has a 3hp motor, no issues thus far. My wire is in-wall, as is the panel (flush mount) so i'm guessing at the wire gauge, suspect I just have 12 gauge.

I should probably run some 10g and put the 20amp breaker in........... someday
 

John Conroy

member
Premium Member
I was using the standard welder plug that both my Miller and Everlast welders came with. The new plugs will be CSA standard 250 volt 20 amp plugs. Same configuration with 2 horizontal flat pins above the ground pin but the welder plug is rated for 50 amps.

20190223_120513.jpg 20190223_120504.jpg
 

PeterT

Ultra Member
Premium Member
It has a 3hp motor, no issues thus far.
Does your motor have a spec plate on it that states its amps? I'm curious what equates to that particular 3hp motor. That's kind of the goofy thing with these offshore machines, sometimes they just state KW (power), sometimes generic 'amps', sometimes FLA 'full load amps'. It's apparently not straightforward to divide watts by wall voltage to yield max current. Above my pay grade as to the specifics of why, but apparently not that simple. Some people advise that your breaker/wire should have X % headroom times FLA to allow for the initial higher current draw, otherwise potential start capacitor issues. I see some TIG welders make this distinction quite specifically, max in-rush amps vs running amps, but for some reason many motors are lacking.
 

PeterT

Ultra Member
Premium Member
I'll measure the start up current when I get it running
I was wondering how I would do this on my mill. I never did, but maybe you can confirm. Do you expose the cables behind the sheath protection & put a clamp meter around one of the wires somewhere along the power harness before it enters the motor?
 

John Conroy

member
Premium Member
I'll use my Fluke 87 digital meter with a clamp style current pick up. It has a "peak min-max" feature that will capture the peak current in a sample time as small as 1 millisecond. I also have a newer Fluke 87-V which has a sample time of 250 microseconds and I plan to compare both meter readings. Although this may not be completely accurate, by taking several samples i should get a good idea. Of course the inrush current will be different based on how much mass is in the chuck and what speed range the lathe starts in. A very heavy item in a large chuck starting at the lathe's highest speed will create a much higher start up current spike than a light item in a small chuck starting at a low speed setting. A more accurate way of measuring this would be with a clamp style amperage pickup and a high speed oscilloscope. I have access to a Picoscope at work and may try that as well and compare the readings from the Fluke 87.
 

John Conroy

member
Premium Member
I haven't worried about inrush current on my mill as it is running on a VFD and ramps the motor current up over a set time (3 seconds is what I have mine set at). So there is much less of a spike at start up. Also the mill never has to start with a large mass in the chuck should make this less of an issue with a mill.
 
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