Need info before buying a new mill

Ray C said:
You'd run a normal power line into the VFD and 3 wires to the motor. You'd just cap-off the wires that normally went to the old motor. Then, you'd program the VFD (usually a slight annoyance because the manuals are never written well) and finally, you'd mount the VFD at some convenient place. -Done. The other controls of the machine would be powered in their usual fashion. It would take me about 60-90 minutes.

I do agree though, get the one YOU are comfortable with.

FWIW, I converted all my machines to 3Ph/VFD for many reasons...

Ray
Click to expand...

Ray,

If I remember right you have the PM 1236 lathe right? Just wondering what type, and HP 3 phase motor you used for your VFD lathe conversion? I have a grizzly G4003G, and my current motor is a chi-com motor advertised at 1 1/2 HP, I can't remember if the PM1236, was 1 1/2, or 2 hp? I am going to convert mine for sure, I purchased 2 mach-tach's for spindle rpm, one for a spare, because I know I will need that to tweak my spindle rpm, with the vfd. I plan on staying close to the correct gear to make it "Easy" on my gearbox, but my lowest spindle rpm now, is 70, and I would like to get down a little slower sometimes for threading! Its pretty quick on the coarse threads!

Bob in Oregon

BTW Ray with the VFD setups does 2hp=2hp? I know with a static 3 phase converter's you loose some HP?
 
Yes, 2 HP = 2HP with a VFD when run at full speed because the motor's HP is calculated at it's top-rated RPM (approx 1800 in this case). The PM's OEM motor is 1.5 HP but, I used a 2 HP (Easson brand) to overcome the times when I run at slightly lower speeds. This is the typical method of sizing a motor when switching to a VFD. BTW: As you suggest, I only use the VFD to vary the speed from about 50 Hz to 60 and still use the gears to select the "major" RPM.

Stay away from static converters, they create very unbalanced power which totally counteracts the whole purpose of a 3ph motor. Also, the replacement motor came with a packing slip that said "Warranty VOID if used with a static converter".

You can get away without an external tachometer as, all VFDs that I know of can be programmed to show the theoretical RPMs on the display panel. Of course, there's a little slip in the motor and the reading might be off a few percent but, it's not all that critical.

I'll send you info on the exact motor type as I don't have that info available at the moment. It was from Global Industrial at about $250 as I recall.

Ray


raross61 said:
Ray,

If I remember right you have the PM 1236 lathe right? Just wondering what type, and HP 3 phase motor you used for your VFD lathe conversion? I have a grizzly G4003G, and my current motor is a chi-com motor advertised at 1 1/2 HP, I can't remember if the PM1236, was 1 1/2, or 2 hp? I am going to convert mine for sure, I purchased 2 mach-tach's for spindle rpm, one for a spare, because I know I will need that to tweak my spindle rpm, with the vfd. I plan on staying close to the correct gear to make it "Easy" on my gearbox, but my lowest spindle rpm now, is 70, and I would like to get down a little slower sometimes for threading! Its pretty quick on the coarse threads!

Bob in Oregon

BTW Ray with the VFD setups does 2hp=2hp? I know with a static 3 phase converter's you loose some HP?
Click to expand...
 
I'm still working on verifying the correct 3 Phase motor for the PM45 and 932 mills. Here's the deal so far... When I swapped my motor, I re-used the B-style plate (which I'm fairly certain is a B3) that was originally on it but, the motor was not an exact fit to the existing adapter face. So, I'm not sure if my motor was a B5 or B15 face. I made a little adapter to make it work. I don't want you guys going through all that nonesense so, I need to verify a couple more things. This is what I believe is the exact replacement needed but, I'm going to double check mine. Please give me a couple days on this because, I'm using the mill a lot these days.

This is the basic motor with a 90L frame with a B5 face and a B3 adapter plate. In the 1st link, you won't need the adapter plate because it's already built into the motor. Im fairly certain this is the ideal correct setup. I asked Matt but, he just orders them from the OEM factory and keeps a few in stock. They are not printed with all the size information.


http://www.globalindustrial.com/p/m...ors/iec-metric-motor-90l-ip55-3ph-c90t17fz6cc

http://www.grainger.com/Grainger/LEESON-B5-Flange-Kit-3GVP3?Pid=search

Don't pull the trigger on anything here until I verify. My setup is a little kludgy because I was working with a "hand-me-down" motor.

Ray
 
And this motor is the 3 Phase drop-in replacement for the PM1236 lathe: http://www.globalindustrial.com/p/m...ors/iec-metric-motor-90l-ip55-3ph-c90t17fz2cc


NOTE: I have no way to confirm this is what's used in the Grizzly machine... There's always a slim chance they used a different motor mounting bracket...




Ray



raross61 said:
Ray,

If I remember right you have the PM 1236 lathe right? Just wondering what type, and HP 3 phase motor you used for your VFD lathe conversion? I have a grizzly G4003G, and my current motor is a chi-com motor advertised at 1 1/2 HP, I can't remember if the PM1236, was 1 1/2, or 2 hp? I am going to convert mine for sure, I purchased 2 mach-tach's for spindle rpm, one for a spare, because I know I will need that to tweak my spindle rpm, with the vfd. I plan on staying close to the correct gear to make it "Easy" on my gearbox, but my lowest spindle rpm now, is 70, and I would like to get down a little slower sometimes for threading! Its pretty quick on the coarse threads!

Bob in Oregon

BTW Ray with the VFD setups does 2hp=2hp? I know with a static 3 phase converter's you loose some HP?
Click to expand...
 
Ray C said:
Yes, 2 HP = 2HP with a VFD when run at full speed because the motor's HP is calculated at it's top-rated RPM (approx 1800 in this case). The PM's OEM motor is 1.5 HP but, I used a 2 HP (Easson brand) to overcome the times when I run at slightly lower speeds. This is the typical method of sizing a motor when switching to a VFD. BTW: As you suggest, I only use the VFD to vary the speed from about 50 Hz to 60 and still use the gears to select the "major" RPM.

Stay away from static converters, they create very unbalanced power which totally counteracts the whole purpose of a 3ph motor. Also, the replacement motor came with a packing slip that said "Warranty VOID if used with a static converter".

You can get away without an external tachometer as, all VFDs that I know of can be programmed to show the theoretical RPMs on the display panel. Of course, there's a little slip in the motor and the reading might be off a few percent but, it's not all that critical.

I'll send you info on the exact motor type as I don't have that info available at the moment. It was from Global Industrial at about $250 as I recall.

Ray
Click to expand...

Ray,

Hey thanks for all your help on this! I will be comparing the motor info you sent me, to my spare motor this weekend, I was aware that RPM display was available on the vfd display, when I looked into it I did not find a very good place on the machine where I could actually mount the VFD controller, and still see the built in display. I am sure as you know the "real estate", or space on these machines is pretty tight! The mach tach looked like a great item so I figured it would probably be less than buying a remote display for the VFD, plus I really liked the design, and the guy selling them! Can't say enough talked to him 3 or four times via e-mail! I Should not admit this but I will, I built 2 of them the last 2 nights! Neither one worked when I supplied power to them, The girlfriend was about ready to run for cover! When I looked at it closer, just like his instructions state, install the microprocessor chip last, they were still sitting on the static safety pad, during my first test! Installed them in the 2 units and they work perfect! Kind of a moron move on my part!
Bob in Oregon
 
Done! The Pm932M-Pdf will be here in a couple of weeks (hopefully :D ) and will be nicely equipped!:thumbzup:

I just need to follow up with the shipping so I can rent the lift truck on the right day.

From some reading around the forum, it is my understanding that the best practice would be to open up the machine for inspection and possibly lubrication making sure everything's alright before start up.


After a few years of machining as part of my job, it as become a passion. I can't believe that I am going to start doing this at home... and for fun!


Thank you Ray C for your time. You made this quite easier for me and helped speed things up. I have also come across quite a few of your posts all around the forums and appreciate your engagement. :+1:
 
So, does the Border Collie chase in circles around the baby? My friend had a border collie (which are sheep dogs) and every morning when the kids gathered at the school bus, the dog ran around and made sure the kids were all lumped together in one spot... Hysterical...


OK, when the unit arrives, check it for shipping damage. You will probably need a 220 V power plug. I don't recall if one is supplied or what style it is but, there are two common types of 220 plug -and I'm not sure if Canada has even a different type than in the States. Next steps are to have your transit path and setup plan before you start moving it. Figure-out exactly how you're going to lift it, where it's going to go etc... Have all the materials (furniture dollies, roller bars etc) on hand and in place.

Have you lifted big stuff before? If not, do you know anyone whose done some rigging?

Anyhow, once you get past transportation and installation, there's not much to do other than get the cosmoline off, lubricate, install the plug -and start exploring the machine. Every mill and lathe from PM gets run at the warehouse for about 10 minutes. DOA units are unheard of -unless the thing got dropped in transit.


ChipsAlloy! said:
Done! The Pm932M-Pdf will be here in a couple of weeks (hopefully :D ) and will be nicely equipped!:thumbzup:

I just need to follow up with the shipping so I can rent the lift truck on the right day.

From some reading around the forum, it is my understanding that the best practice would be to open up the machine for inspection and possibly lubrication making sure everything's alright before start up.


After a few years of machining as part of my job, it as become a passion. I can't believe that I am going to start doing this at home... and for fun!


Thank you Ray C for your time. You made this quite easier for me and helped speed things up. I have also come across quite a few of your posts all around the forums and appreciate your engagement. :+1:
Click to expand...
 
In fact these two are Australian shepherds. They are quite similar to Border Collies and yes, they do tend to herd the children! But they are very gentle with them At 1 year and a half, my son is starting to have much fun with them.

I just looked on the PM site. The FAQ section mentions that the machine does not come with the plug so I will use those of my choice.

I have some experience rigging machines as it is part of my job, (when we dismantle or install packaging lines we do most of the rigging ourselves). I am confident I will be able to take the mill in place, especially with a lift truck and a reliable friend.

I still plan to make a wheeled frame for moving the machine around the shop if needed similar to what mskobier did :http://www.hobby-machinist.com/showthread.php/16229-My-New-Mill-PM-45-PDF

I will have to finish this before the machine gets here because I will need the lift truck to put the machine and the stand on the mobile frame. So getting information on the cast iron frame dimensions and building the frame is becoming my top priority :)
 
Which base did you go with? I think there are a couple options.
 
The PM932 comes standard with the cast iron base from what I have seen on the web site
 
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