New to me RF 45 ..... In the shop

[Proxule]

@Proxule I assume you pulled the rotor/shaft assembly & turned the shaft down in the lathe? How much effort removing & dealing with bearings & such?


Was your RF45 motor kaput or you wanted to replace/upgrade for other reasons? I recall the stock spindle speed was ~1800 RPM but I can't recall if that was the 1:1 to motor spec or reduced. Are you saying 3600 RPM you doubled the speed?

I see a big capacitor box so its single phase, were there any issues integrating the wiring or that aspect just stays with the motor itself, not the machine stop/start?

Correct, I pulled it all apart, mounted it between centers, turned the DE down to the dimensions I wanted and milled accordingly.
I did not remove bearings, was no need, just pull the shaft with bearings attached out of the bell housings.

"I assume 145TC is an IMP spec, so an IMP shaft which you turned down to Xmm diameter the RF45 needed? And the adapter plate was needed to marry the IMP bolt pattern to (assume) metric RF45 bolt pattern?"

EXACTLY

There is no capacitor box, that's just a big pecker head - as it came from the manf. Its a 2hp 3ph motor.
Start and stop are from the VFD, and a big red button for E stop.

 

[PeterT]

There is no capacitor box, that's just a big pecker head - as it came from the manf. Its a 2hp 3ph motor.

ah, I get it now. That's what confused me

 

[Proxule]

For posterity
Vfd, E stop, rpm display.

 

[PeterT]

@Proxule Nice clean setup, congrats. Sorry to keep asking questions outside the original thread scope

- back to the 3600 RPM now that I see its 3P/VFD, are you spinning the spindle at this RPM? The reason I mention is my Taiwan RF-45 was listed at ~1800 RPM (max). That may have been a motor induced spec through the primary gear ratio, but I recall some guys overclocked their (CNC conversion) RF45's & there was discussion the stock bearings were not up to snuff. They ended up replacing those. I'm not sure if t was precautionary step during conversion rebuild or they cooked them at higher RPM & that's what triggered upgrade. Comments?

- my RF45 was a clatter box from day-1. The Chinese RF-45 at Modern Tool was significantly quieter. I heard 2 culprits were 1) the main spindle shaft splines fit or lack thereof 2) bad motor keyway related. Did yours quiet down after motor swap or about the same?

- so do you typically select a mid range manual lever combination & do the actual RPM adjusting with VFD knob?

- one thing I always thought would be nice is if you could mount a tap, feed in under low RPM & then either stop with some better braking predictability or better yet reverse out of the hole somewhat instantaneously. Is that within the VFD programming capability?

 

[trlvn]

I'm not convinced that is what I want , leaning more towards leaving the controls and wiring in the machine original , not rewiring the machine , avoiding complexity and additional controls .

It's a gear drive .......... I'm good with that .

I will mention this again because no one has responded to post # 4 , where I posted a picture of a digital phase convertor

I don't have any personal experience but I will note that the description of the unit on Amazon says:

"No switch can be added between the converter and the motor. "

So it really forces you into at least some re-wiring of your machine.

Craig

 

[Mike R]

I am about to wire up my surface grinder with 2 VFD's. The sole purpose of the VFD's is to get 3 phase out at a fixed 60hz (what you want in effect). So very much used in the same way as the digital phase converter you show. The difference as pointed out by Craig is that the digital phase converter has no inputs for low voltage switches, meaning you'll need to put the switch of the 208/220V and how ever many amps ahead of the phase converter. With a VFD the switch can either be a button on the VFD (run and stop - see Proxule's picture above), or it can be an external switch that runs from two terminals on the vfd to a remote mounted switch - this is what I'm about to do on my B&S surface grinder. The main reason is to get a switch located in a convenient spot while the VFD's are tucked away somewhere else away from swarf, dust, fingers, etc.

In your case the VFD could be located at the back, near where the power comes in to the contactor, and you can even reuse the e-stop, clockwise, counter clockwise start buttons very easily (they will go to terminals on the VFD). Yes, you would need to rewire things a bit - 24VDC transformer goes away, so does the contactor (actually cleans things up a bit).

Cost wise they should be nearly the same, VFD very likely will be cheaper.

Having looked at the Amazon offering, there are more conditions on use that seem to make the Digital Phase converter a less than ideal option.
- " Please choose the converter corresponding to the power of the motor, the converter can't support the motor higher than its own power, nor can it support the motor whose power is lower than its own." and "The power of the connected devices must match the recommended power of the converter, no matching across power ranges." I read this as you need to match closely the motor power to the phase converter so you need to find a 1.5KW (2hp) digital phase converter.

There are other conditions I don't understand on the digital phase converter: "To ensure motor and personal safety, this device must be used in conjunction with an air switch" along with a diagram I don't understand about motor running versus not running.

Anyways, you can do what suits you but it seems to me that if running a 3 phase motor at fixed frequency (60Hz) achieves what you want, then a VFD is probably the lowest cost solution and you can find support to do it from members here. I'm not so sure about the other options.

 

[Susquatch]

"I assume 145TC is an IMP spec, so an IMP shaft which you turned down to Xmm diameter the RF45 needed? And the adapter plate was needed to marry the IMP bolt pattern to (assume) metric RF45 bolt pattern?"

EXACTLY

Gotta give you extra credit for helping others know what you are replying to by using quotes.

Thought you might like to know that there are three easier ways to do this.

1. Just block only the part of the post that you want to reply too, and then a small box will appear that says "+quote|reply". Pressing +quote will add it to a list of quotes you have made that you can then use in this reply or in any future one.

2. Pressing the "reply" instead of "+quote" will add it as a regular reply at the location where your cursor is.

3. Reply to the entire message and then press 3 returns anyplace in the message to separate the quote into sections that you can reply to individually.

Again, thanks for thinking of others the way you obviously did!

 

[Gearhead88]

Having looked at the Amazon offering, there are more conditions on use that seem to make the Digital Phase converter a less than ideal option.
- " Please choose the converter corresponding to the power of the motor, the converter can't support the motor higher than its own power, nor can it support the motor whose power is lower than its own." and "The power of the connected devices must match the recommended power of the converter, no matching across power ranges." I read this as you need to match closely the motor power to the phase converter so you need to find a 1.5KW (2hp) digital phase converter.

Thankyou

This is helpful .

I was looking for and hoping to get some opinions on the " Asian " digital phase convertor .
Originally I was thinking this might be a reasonable option , not so much anymore , the reviews are an eye opener , several customers fried their shit .
I wanted to see what others though of this device , I'll admit , I do not know enough about this to decide on my own , if it's a cheesy POS , a few opinions is all it's going to take for me to rule out using a Digital Phase Convertor.

For me , to go with a VFD , the confusion starts with what to do with all of the existing / original electrical equipment that is on the machine .

 

[DavidR8]

Thankyou

This is helpful .

I was looking for and hoping to get some opinions on the " Asian " digital phase convertor .
Originally I was thinking this might be a reasonable option , not so much anymore , the reviews are an eye opener , several customers fried their shit .
I wanted to see what others though of this device , I'll admit , I do not know enough about this to decide on my own , if it's a cheesy POS , a few opinions is all it's going to take for me to rule out using a Digital Phase Convertor.

For me , to go with a VFD , the confusion starts with what to do with all of the existing / original electrical equipment that is on the machine .

I'm an electrical idjit and my approach would be to figure what the current (no pun intended) electrical is doing and then decide what I want to keep.
It's a simple machine so it should have relatively simple electrics. I see an emergency stop, and maybe fwd/rev switches?
Is the power feed 110V?

 

[Gearhead88]

I'm an electrical idjit and my approach would be to figure what the current (no pun intended) electrical is doing and then decide what I want to keep.
It's a simple machine so it should have relatively simple electrics. I see an emergency stop, and maybe fwd/rev switches?
Is the power feed 110V?

The panel where the controls are has forward & reverse switches and an E stop .





And , Yes , the power feed , digital readout are both 110 v . I added a quad 110v box for those two items and a work light , the fourth spot is for a coolant pump . There was a coolant system on this machine when it was new but it was stored badly and the pump is fubared , the reservoir is missing , presumably tossed because it was clogged with congealed snot .

 

[Susquatch]

For me , to go with a VFD , the confusion starts with what to do with all of the existing / original electrical equipment that is on the machine .

I understand that. You probably don't need to use any of it except the switches. The VFD usually replaces everything inside the panelbox. So all you probably need to do is rewire or replace the external switches on your machine. These often terminate on a busbar inside the panel box. For my lathe, I plan to add another busbar that catches all these connections and routes them to my VFD. I might need a few other components to resuse the existing switches.

 

[Proxule]

@Proxule Nice clean setup, congrats. Sorry to keep asking questions outside the original thread scope

I am always here to help.

- back to the 3600 RPM now that I see its 3P/VFD, are you spinning the spindle at this RPM? The reason I mention is my Taiwan RF-45 was listed at ~1800 RPM (max). That may have been a motor induced spec through the primary gear ratio, but I recall some guys overclocked their (CNC conversion) RF45's & there was discussion the stock bearings were not up to snuff. They ended up replacing those. I'm not sure if t was precautionary step during conversion rebuild or they cooked them at higher RPM & that's what triggered upgrade. Comments?

I am spinning the main spindle at 3600, and then adjusting the speed higher or lower through the VFD, but only to a max of 2500 RPM
So I will pick what ever gear combo I want or like, then adjust to what ever I feel see or hear appropriate for the endmill or drill.
But in the highest speed setting I will not go over 2500 total RPM indicated by my arduino rpm tachometer readout I made.
When I bought this mill I had pulled every nut bolt and bearing off, total rebuild, paint, new bearings throughout the head minus the tapered spindle bearings ( they just got new grease ), and adjusted the spindle preload. Anyway long story short. I noticed from my trials that anything above 2500 rpm really smoked the original bearings and the oil in the head started to really chop and foam up, Some times leading to surging from the motor.

Folks swap out the tapered bearings for AC back to back for increased RPM ( 6k + ). From what I have read.
I had no plans to run that fast, and I will never convert to CNC

The RF45 and RF30 I think also, came with the option of 1750/3600 rpm - Hence my setup. Was a no brainier as many smaller carbide endmills like the higher RPMS.

You question and assumptions are spot on regarding this topic !

- my RF45 was a clatter box from day-1. The Chinese RF-45 at Modern Tool was significantly quieter. I heard 2 culprits were 1) the main spindle shaft splines fit or lack thereof 2) bad motor keyway related. Did yours quiet down after motor swap or about the same?

Ah yes, this issue I have too. It did indeed quiet down with the new 3 ph motor, but it was not due to the keyway.
The biggest culprit it the gear oil, or what ever yours has ( I seen old and new RF30//45 manuals call for ISO 68 or some sort of gear oil ), and the clatter of those spur gears ( straight cut ).
I tried verious wrights of oil, Iso 32 46 68 and various gear oils. 75/90 was a great compromise between added heat and foam / making that terribly loud head quiet down a bit. Several dB worth - according to my tests.
Probably another reason it surges above 2500rpm. I am sure you could get 2800 or 3K with a lighter oil like iso 46

That main spindle splines sure do like to clackity clack back and forth, especially when its not loaded or cutting, Best fix I found was heavy grease slapped onto the splines. That eventually disappears from the splines. Makes a mess but it does quiet things down.
I leave it dry now, Wasn't worth that headache. And swarf magnet

- so do you typically select a mid range manual lever combination & do the actual RPM adjusting with VFD knob?

For monster hole drilling or hogging I will select a quiet low speed combo and adjust rpm ( there are indeed quiet gear combos ) try yours out and find the combo that is quiet, I am surprised some combos are almost silent. Then adjust your VFD from there.
But for most things I am in the mid or upper range of speed and adjust my vfd from there.

- one thing I always thought would be nice is if you could mount a tap, feed in under low RPM & then either stop with some better braking predictability or better yet reverse out of the hole somewhat instantaneously. Is that within the VFD programming capability?

Reversing out instantly is easily achieved with this flavor of VFD. Although I don't have it setup that way. No sense in slamming things into 0 rpm - But its adjustable with in the VFD parameters for X seconds slow down or start up.
I have power down feed on my RF45 - an options I seldom see. So I didn't put much thought into this to be honest.

Thanks for the questions

 

[DavidR8]

Here's a thought:
I bet one of our members could make a wiring harness that would be 'plug and play' for your machine. You buy the VFD so that's a known entity and then someone makes up the wiring for the switches with nice long pigtails for connectors to be crimped on, Programming the VFD would only be a few parameters and that could be easily detailed and provided to you.
When I did my mill I knew zero about what I was doing and followed a video by Clough42, quite literally frame by frame and it worked out great.

 

[Downwindtracker2]

One of the things I just learned, which at my age might be only be for a short time. chuckle .Switches can be used by themselves ,or as with mag starters which will need a transformer to power them. This was my question of understanding the meaning of sink or source. I'm powering my switches off the VFD. I could be wrong here, but I think that's what is called source. Using mag starters gives you the safety of no start after power outage.

 

[Jswain]

I would always be willing to help with whatever route you go as well.

I'm no electrical guru, and a crappy machinist but I'm pretty good at figuring stuff out.

 

[Susquatch]

One of the things I just learned, which at my age might be only be for a short time. chuckle .Switches can be used by themselves ,or as with mag starters which will need a transformer to power them. This was my question of understanding the meaning of sink or source. I'm powering my switches off the VFD. I could be wrong here, but I think that's what is called source. Using mag starters gives you the safety of no start after power outage.

I'm not sure I follow all that. I don't know why sourcing switches from the VFD is a problem. I think it's an advantage.

No VFD I ever saw would start after a power outage without first turning it off. VFDs contain all the safety features normally implemented through relays and control systems.

 

[Downwindtracker2]

In my Hitachi, it's a step in programing with a jumper wire to VFD power feed. I have just gone over that. It wasn't happy with my programming there either, instead I'll just put a mag starter on the power cord. All the machines except the DeWalt have one, and I have one for it, too. Another someday project.

I just put Mark's PDF from Hobby Machinists on my laptop . He replied yesterday to my Help cry. I use Downwindtracker2 (a man of foolish pursuits) . In that PDF he uses the original switches , he told me to just skip over that.

 

[Susquatch]

In my Hitachi, it's a step in programing with a jumper wire to VFD power feed. I have just gone over that. It wasn't happy with my programming there either, instead I'll just put a mag starter on the power cord. All the machines except the DeWalt have one, and I have one for it, too. Another someday project.

I just put Mark's PDF from Hobby Machinists on my laptop . He replied yesterday to my Help cry. I use Downwindtracker2 (a man of foolish pursuits) . In that PDF he uses the original switches , he told me to just skip over that.

I still don't follow. It's probably just terminology.

What the heck is a mag starter?

@BaitMaster - do you pickup what he is putting down?

 

[Downwindtracker2]

It's what I have taken to be a magnetic switch (relay) with heating coils for O/L. Understand I'm not an electrician . I was a just a millwright. I let sparky deal with those dangerous wires. Men have gotten killed messing in those cabinets .

He said I could have miss wired the pot or my setting for Hz are off. Either is quite possible.

 

[Susquatch]

It's what I have taken to be a magnetic switch (relay) with heating coils for O/L.

I think most people call them contactors (for high current) or control relays (for lower current). I generally just call them all contactors.

Generally, you don't need them with a VFD. The VFD provides all those functions as, well as the conversion from single phase to three phase and the variable frequency for motor speed control.

He said I could have miss wired the pot or my setting for Hz are off. Either is quite possible.

Yes, entirely possible.