Machine tool guru's

[Thumper68]

I have a line on a Index 645 milling machine, I checked it out in person today and if I can get it for the right price I will bring it home.

Need some expert input, The mill has 2 motors, one for the head and a 2nd motor for the table feeds. Can I run both motors off of 1 VFD or will I need 2?

Added for anyone who cares:
x axis has .022 backlash
y axis has ,010 backlash
z axis has .040 backlash

The quill seems to be tight and free moving and is a R8, had to check since a lot of the Index mills came with a B&S #9 taper.

Unfortunately no tooling is available with it, but it does have the right angle attachment.

2nd question and I know this varies all over but where would you feel comfortable $$$ wise buying a similar machine?
View media item 70959View media item 70960

 

[blazemaster83]

Not sure about the vfd because I don't have one, but an index 645 is a good machine as long as it's in decent shape. I would trade my mill for one (3hp beaver vbrp).

 

[Mark in Indiana]

Thumper,
Nice find! No home is complete without a milling machine. If you get it, I hope you post a thread when you start making chips.

I have a Cincinnati MH2, with an independent overarm, that uses 2 motors. A 1hp motor for the overarm (for vertical milling) and a 5hp motor for horizontal milling and table movement. I bought it from a friend who installed the VFDs. Mine has one VFD per motor.

If you haven't yet, you may want to check out these forums:
www.hobby-machinist.com
www.practicalmachinist.com
Both are good sources of information.

 

[Doug Arthurs]

Since you would need to feed the table and run the spindle at the same time you would need 2 VFD's.

 

[tdkkart]

The only issue with using one VFD for both motors is that you will change the speed of both motors if you use the VFD for variable speed. Otherwise, just look at the current output spec, and as long as you don't exceed that you'll be fine, just run it at 60hz and use the original speed change system on the mill.

 

[OccupantRJ]

I plan to run my Bridgeport with a VFD for the spindle, and a static phase converter for the table motor.

 

[Carla]

Hi, Thumper,

The Index is a very good quality make of light mill, and has a reputation for good service.

That said, what matters is the level of wear in the ways and screws, relative to the level of accuracy you wish to be able to do on the machine. If at all possible, get someone familiar with machine tools to inspect the machine on your behalf. (if the longitudinal table ways are worn in the centre enough that the table will be a little 'shaky' in mid-travel, that will affect the part finishes you will be able to get.....and it doesn't take very much wear to make a difference)

You could consider just using a 'rotary phase converter' for both motors, as the original spindle and feed speed ranges with constant speed motors are quite adequate for any work the machine may be called upon to do.......variable speed with a VFD is a really needless refinement.

cheers

Carla

 

[Ign]

2 motors - this sounds like a perfect opportunity for an RPC

Before you know it you'll find some other 3ph tool you can't refuse and that will also run on your RPC...and the next one....and the next one

 

[HanShotFirst]

The Index was made by Wells-Index, who is still in business; and still supports their mills with parts.

Wells-Index Website
http://www.wells-index.com/

More information on your specific machine
http://www.lathes.co.uk/index/

Provided you got it at a decent price, I predict you'll have a lot of fun with your new mill. The Index is a very nice machine.

 

[catalytic]

One very rough idea of price: 1k-2.3k if it is from a non-dealer individual or shop. Note: I DONT know the market in MN -- I am familiar with the midwest and socal. Index makes a nice machine, but too bad it doesn't have a DRO. Most of us, except for the really old and stubborn, rely on DRO's a LOT, and they can be a bit tricky to properly install if you haven't done it before.

 

[Thumper68]

Thumper,
Nice find! No home is complete without a milling machine. If you get it, I hope you post a thread when you start making chips.

I have a Cincinnati MH2, with an independent overarm, that uses 2 motors. A 1hp motor for the overarm (for vertical milling) and a 5hp motor for horizontal milling and table movement. I bought it from a friend who installed the VFDs. Mine has one VFD per motor.

If you haven't yet, you may want to check out these forums:
www.hobby-machinist.com
www.practicalmachinist.com
Both are good sources of information.

Been reading on both of those for years thanks.

Since you would need to feed the table and run the spindle at the same time you would need 2 VFD's.

That is what I was thinking, have to figure that into the price to get it up and running.

The only issue with using one VFD for both motors is that you will change the speed of both motors if you use the VFD for variable speed. Otherwise, just look at the current output spec, and as long as you don't exceed that you'll be fine, just run it at 60hz and use the original speed change system on the mill.

Since this is a belt drive unit the VFD for speed control would be nice.

I plan to run my Bridgeport with a VFD for the spindle, and a static phase converter for the table motor.

That is not a bad idea and might save some coin.

Hi, Thumper,

The Index is a very good quality make of light mill, and has a reputation for good service.

That said, what matters is the level of wear in the ways and screws, relative to the level of accuracy you wish to be able to do on the machine. If at all possible, get someone familiar with machine tools to inspect the machine on your behalf. (if the longitudinal table ways are worn in the centre enough that the table will be a little 'shaky' in mid-travel, that will affect the part finishes you will be able to get.....and it doesn't take very much wear to make a difference)

You could consider just using a 'rotary phase converter' for both motors, as the original spindle and feed speed ranges with constant speed motors are quite adequate for any work the machine may be called upon to do.......variable speed with a VFD is a really needless refinement.

cheers

Carla

Thanks Carla, I did as good of a once over as I could with out it being under power and from my reading I looks like I should be able to tighten up the x axis a bit.

2 motors - this sounds like a perfect opportunity for an RPC

Before you know it you'll find some other 3ph tool you can't refuse and that will also run on your RPC...and the next one....and the next one

I already have several 3ph machines in the shop but I wanted the speed control on all so far and as of right now I think the speed control would be nice on at least the head.

The Index was made by Wells-Index, who is still in business; and still supports their mills with parts.

Wells-Index Website
http://www.wells-index.com/

More information on your specific machine
http://www.lathes.co.uk/index/

Provided you got it at a decent price, I predict you'll have a lot of fun with your new mill. The Index is a very nice machine.

In this case the machine was made by Index, wells bought them in 71 along with the change of name to Wells-Index.

Thanks again to everyone for the timely input.

 

[LXCam]

I doubt the table drive motor is 3ph. I bet you find its single phase and convertible between 240 or 480 with its own built in DC drive. Take a good look at it and confirm the power requirements. If it is three phase it will still have its own built in speed selector so you could run it off a very small cheap VFD, it will be a fractional HP motor anywhere from a 1/10th to a 1/4 most likely.

Good luck, I hope you get it as having a good mill is something every man worth his salt with a shop should have one.

 

[Thumper68]

One very rough idea of price: 1k-2.3k if it is from a non-dealer individual or shop. Note: I DONT know the market in MN -- I am familiar with the midwest and socal. Index makes a nice machine, but too bad it doesn't have a DRO. Most of us, except for the really old and stubborn, rely on DRO's a LOT, and they can be a bit tricky to properly install if you haven't done it before.

okay that is where I thought I would have to be on it, we will see by the middle of next week.

I have been looking at DRO's and nine4gmc found a cheap one on ebay that looks like it would be good enough for me, I can always upgrade later.

 

[Thumper68]

I doubt the table drive motor is 3ph. I bet you find its single phase and convertible between 240 or 480 with its own built in DC drive. Take a good look at it and confirm the power requirements. If it is three phase it will still have its own built in speed selector so you could run it off a very small cheap VFD, it will be a fractional HP motor anywhere from a 1/10th to a 1/4 most likely.

Good luck, I hope you get it as having a good mill is something every man worth his salt with a shop should have one.

From what I have found online the factory drive motor is a 1/3hp 3ph

The data plate was pointed the wrong way for me to see it today during the inspection.

 

[Thumper68]

Well SWMBO and I talked it over and we decided to go ahead and try and make the deal. Seller will not be around for the holiday weekend and He wants me to call Tuesday night to let him know, Fingers Crossed that we can come to a number that works for both of us.

He also has a few other things I am interested in so a nice package deal.

 

[catalytic]

Well SWMBO and I talked it over and we decided to go ahead and try and make the deal. Seller will not be around for the holiday weekend and He wants me to call Tuesday night to let him know, Fingers Crossed that we can come to a number that works for both of us.

He also has a few other things I am interested in so a nice package deal.

I should have mentioned -- the real cost of owning/operating a milling machine will be in the tooling (and also in any repair parts needed).

Let's suppose you already have:
micrometers
dial test indicators & stands
calipers
height gauge (I find these essential if you don't have a DRO on a mill)

You're still going to need:
Kurt 6" Vise
DRO(?)
Collet set, or at very least, end mill holders in the common sizes
Parallels set
Hold downs & stops
Various end mills. Start with 2-flute HSS center cutting and use the shorter, fatter ones (i.e. 3/4" dia) unless you have a reason not to (i.e. making a small channel) as short+fat = more rigid.
Face mill
(OK, now with all of the above, you can clamp a block in the vise and square it up...but to actually make it in to something you will likely want...):
Center drills
Countersinks
Counterbores (I use these a ton b/c I design parts that assemble with hex head machine screws)
Reamers
Machine tap set
Tap handles

Many people have lists of what they need/use online, but this should be enough to get started and have a little fun. Ebay is your friend for tooling -- many lots of NOS end mills still in wax, etc. can be found there.

My point is just that, if you plan to get a mill, the machine itself often costs less than the tooling you need to operate it, even assuming you can get tooling NOS or at auctions. If this one comes with no tooling/DRO, then I would aim for the lower side of the price range (again, you know the Duluth market and I don't, so take with a grain of salt). Also, maybe they can at least include the collets they used on this machine?

One more thing -- print out and use a speed/feed chart. You will get much better finish and not break end mills.

 

[Provincial]

You seem to have done your research on the Index mills. This fellow is quite knowledgeable on them, and this is a link to his DRO installation:

http://www.garagejournal.com/forum/showthread.php?t=273996

 

[MushCreek]

I've had an Index- good, rugged machines. I'd be happy to find one for $2K around here (SC)

 

[dr_clyde]

I like Wells-Index. They make a nice knee mill. I would feel comfortable paying up to $2500 if its in good shape.

Like others have pointed out, the money is in the tooling.

As far as the motors, run a RPC. You would need two VFDs otherwise.

 

[Thumper68]

I should have mentioned -- the real cost of owning/operating a milling machine will be in the tooling (and also in any repair parts needed).

Let's suppose you already have:
micrometers
dial test indicators & stands
calipers
height gauge (I find these essential if you don't have a DRO on a mill)

You're still going to need:
Kurt 6" Vise
DRO(?)
Collet set, or at very least, end mill holders in the common sizes
Parallels set
Hold downs & stops
Various end mills. Start with 2-flute HSS center cutting and use the shorter, fatter ones (i.e. 3/4" dia) unless you have a reason not to (i.e. making a small channel) as short+fat = more rigid.
Face mill
(OK, now with all of the above, you can clamp a block in the vise and square it up...but to actually make it in to something you will likely want...):
Center drills
Countersinks
Counterbores (I use these a ton b/c I design parts that assemble with hex head machine screws)
Reamers
Machine tap set
Tap handles

Many people have lists of what they need/use online, but this should be enough to get started and have a little fun. Ebay is your friend for tooling -- many lots of NOS end mills still in wax, etc. can be found there.

My point is just that, if you plan to get a mill, the machine itself often costs less than the tooling you need to operate it, even assuming you can get tooling NOS or at auctions. If this one comes with no tooling/DRO, then I would aim for the lower side of the price range (again, you know the Duluth market and I don't, so take with a grain of salt). Also, maybe they can at least include the collets they used on this machine?

One more thing -- print out and use a speed/feed chart. You will get much better finish and not break end mills.

I have known that I will be getting a mill at some point so I have been collecting tooling and measurement instruments for years.

As of right now I will be adding a DRO and I will need a new set of hold downs and a collet set.

Then I will be adding job specific tooling as needed.

You seem to have done your research on the Index mills. This fellow is quite knowledgeable on them, and this is a link to his DRO installation:

http://www.garagejournal.com/forum/showthread.php?t=273996

Thanks for the link.

I've had an Index- good, rugged machines. I'd be happy to find one for $2K around here (SC)

That has been the issue, all the mills that have come up for sale within 100 miles or so have either been clapped out **** or the owner thought they were cast from gold.

I like Wells-Index. They make a nice knee mill. I would feel comfortable paying up to $2500 if its in good shape.

Like others have pointed out, the money is in the tooling.

As far as the motors, run a RPC. You would need two VFDs otherwise.

I am still going back and forth on VFD's or RPC in the end it will come down to the numbers.

Thanks again to everyone for the comments and ideas.

 

[OccupantRJ]

Two VFD will cost you $250 or less for motors 1 hp or less. TECO is a popular unit.

 

[larry_g]

You seem to have done your research on the Index mills. This fellow is quite knowledgeable on them, and this is a link to his DRO installation:

http://www.garagejournal.com/forum/showthread.php?t=273996

Provincial linked to my thread so I won't go into that. I will add that my mill is 2 or 3 generations older than the one your looking at. For the mill your looking at I would want to be under $1500. I run my whole shop with an RPC that has served me well for years. Some investigating I did years ago was to put a VFD on the spindle motor of mine. I was told that I could run the VFD off the converter power. So it might be to your advantage to start with an RPC and if you find that belt swapping is to much trouble then add a VFD in for the spindle. I never did the VFD as I have a two speed motor on mine and find that belt swapping is not to often.

You mention that you have other 3 phase machines, how are your powering them?

lg
no neat sig line

 

[Thumper68]

Provincial linked to my thread so I won't go into that. I will add that my mill is 2 or 3 generations older than the one your looking at. For the mill your looking at I would want to be under $1500. I run my whole shop with an RPC that has served me well for years. Some investigating I did years ago was to put a VFD on the spindle motor of mine. I was told that I could run the VFD off the converter power. So it might be to your advantage to start with an RPC and if you find that belt swapping is to much trouble then add a VFD in for the spindle. I never did the VFD as I have a two speed motor on mine and find that belt swapping is not to often.

You mention that you have other 3 phase machines, how are your powering them?

lg
no neat sig line

The other 3ph stuff in the shop is on VFD's

I called and talked to the guys at American Rotary. We went over my needs and specs on the machines I have and the specs on the new mill, His suggestion is a AR 5, with that I can run all 3 machines, Mill, Lathe and bandsaw at the same time is needed, I just can't start them all at once.

The AR 5 comes in at $425 plus shipping, that will allow me to sell the 2 VFD's I have and come out at a wash if I want to.

I like the idea of including a VFD for the spindle motor on the Mill. If I take the one off the band saw which really is not needed with the reeves drive then I can get in at a price I feel comfortable with, then both the lathe and mill will have great speed control.

Lots here to think about now.

Once again thanks to all who have provided insight.

 

[JoeFin]

The other 3ph stuff in the shop is on VFD's

I called and talked to the guys at American Rotary. We went over my needs and specs on the machines I have and the specs on the new mill, His suggestion is a AR 5, with that I can run all 3 machines, Mill, Lathe and bandsaw at the same time is needed, I just can't start them all at once.

Good move Thumper

I bought one of those TECO VFDs and ended up giving it away. By the time you derate a 5Kw VFD to run off single phase you don't have enough power to start up a 2 Hp motor without creeping up the speed ever so slowly.

I have a 10 Hp Ronk RPC that I piped a 3 phase electrical circuit around my entire shop to feed all my machines. Most professional grade manual machines will incorporate multiple motors which becomes a problem very quickly for VFDs

Besides - you can not run CNCs off of VFD power supplies

 

[MShaw]

As to the screw backlash, it does not seem excessive. Also, you should be able to adjust the backlash if that much bothers you. Since some backlash is invincible you should make all your final positionings in the same direction so the backlash is not an issue.

 

[Thumper68]

As to the screw backlash, it does not seem excessive. Also, you should be able to adjust the backlash if that much bothers you. Since some backlash is invincible you should make all your final positionings in the same direction so the backlash is not an issue.

You are correct and it is something that I will have to deal with once it is home (fingers crossed)

I talk more about it in this video I made yesterday.
<iframe width="560" height="315" src="https://www.youtube.com/embed/shvFE7qm0js" frameborder="0" allowfullscreen></iframe>

 

[Monkey Milk]

If your going to pay for an American rotary machine you should look at phase perfect.

 

[E.rodz]

I am a bit confused by the table feed? I am assuming that it is just for the up and down of the table? Normally with a Bridgeport you have a drive motor which would normally be 3phase and table feed motors are single phase d/c motors with a variable speed potentiometer on it already. If I had no tooling of my own and I needed to by all of that separate I would say not to pay over 2,000 for it tops . Because like others have mentioned on here the money is in the tooling .if you have to buy a digital readout and you definitely want a readout on it! A vid.drive collets,endmils,drillchucks,parralels,flycutters,a Kurt vice etc etc. you would be better off buying one with all of that for 3,500 loaded up and you would be money and a ton of time ahead. This is going to weigh about 2,000# and very top heavy so if you buy it bring the table all the way down and tip the head down as well.. if you already have a phase convertor I would skip the vfd. Swapping belts just takes a second. Good luck with the machine whatever decision you make.

 

[OccupantRJ]

I am a bit confused by the table feed? I am assuming that it is just for the up and down of the table? Normally with a Bridgeport you have a drive motor which would normally be 3phase and table feed motors are single phase d/c motors with a variable speed potentiometer on it already. If I had no tooling of my own and I needed to by all of that separate I would say not to pay over 2,000 for it tops . Because like others have mentioned on here the money is in the tooling .if you have to buy a digital readout and you definitely want a readout on it! A vid.drive collets,endmils,drillchucks,parralels,flycutters,a Kurt vice etc etc. you would be better off buying one with all of that for 3,500 loaded up and you would be money and a ton of time ahead. This is going to weigh about 2,000# and very top heavy so if you buy it bring the table all the way down and tip the head down as well.. if you already have a phase convertor I would skip the vfd. Swapping belts just takes a second. Good luck with the machine whatever decision you make.

On a bridgeport, at least the earlier years, the x axis motor was usually 3 phase constant speed, and the travel was adjusted manually through a multi speed transmission fed by the motor. Right now, I am running the head on mine with a static phase converter to check it out, and it has done quite well. I just obtained a Teco VFD and will use it to drive the head, then switch the spc over to power the 3 phase table feed motor on mine.

 

[Thumper68]

If your going to pay for an American rotary machine you should look at phase perfect.

Thanks for the link, I checked out the site and did not see where they are made, I will have to call them on Tuesday and get more info.
American Rotary are made in WI, and from what I have heard their customer service, before and after the sale is top notch.

I am a bit confused by the table feed? I am assuming that it is just for the up and down of the table? Normally with a Bridgeport you have a drive motor which would normally be 3phase and table feed motors are single phase d/c motors with a variable speed potentiometer on it already. If I had no tooling of my own and I needed to by all of that separate I would say not to pay over 2,000 for it tops . Because like others have mentioned on here the money is in the tooling .if you have to buy a digital readout and you definitely want a readout on it! A vid.drive collets,endmils,drillchucks,parralels,flycutters,a Kurt vice etc etc. you would be better off buying one with all of that for 3,500 loaded up and you would be money and a ton of time ahead. This is going to weigh about 2,000# and very top heavy so if you buy it bring the table all the way down and tip the head down as well.. if you already have a phase convertor I would skip the vfd. Swapping belts just takes a second. Good luck with the machine whatever decision you make.

On the Index mill the table feed is built in and runs off a 2nd motor, it is not a add on like you see on a Bridgeport.

Yeah the tooling can add up quick, I have a good base of measurement tools, and a small collection of end mills, drills, reamers. To start I will be getting a few needed tools, face mill, fly cutter boring head, R8 collet set, hold down set to match the T slots in the table. Then I will add tools as needed for specific jobs.

The mill does come with a vise and there is another available as well as 2 rotary indexers, if I can add those within my budget then they will be coming home too. There are a few other tools and equipment that are available that I might try and add in mostly to flip and fund stuff I need.

 

[larry_g]

So in your mill tooling thread you ask for tool recommendations. Can we assume that you now have this mill in your possession?

lg
no neat sig line

 

[tool_scrounge]

Usually for me the deciding factor of Variable Frequency Drive (VFD) vs. Rotary Phase Converter (RPC) is:

Controls: VFD's can blow up if you have any relays or switches between the VFD and the motor. So if you have a mill with a single speed motor, no problem. But if you have a 2 speed lathe with relay controls, hooking up a RPC is much easier. With a VFD most folks pick one motor speed and wire around all the control relays.

Cost: VFD is more expensive than RPC when you get much above 1HP or have multiple motors.

Also, it is pretty easy to build an RPC if you have electronics knowledge.

But one thing to remember is that most 3 phase motors do not have thermal overload protection like a 1 phase motor. A VFD does provide current limit protection. A typical RPC is usually oversized to allow for hard starting loads (ie lathe with big chuck) but there is no current protection. So if you plug your 1hp mill motor into a 10hp RPC, you can cook the motor if you overload it too much.

Solution? Use a manual motor starter. These are basically 3 phase motor switches with a resetable circuit breaker built in. See attached photo. The current is usually adjustable over a limited range (2.5-4A in the one in the photo). They are pretty cheap on Ebay for new/used US or European made ones. I avoid the Chinese built no-name ones. You could also use time lag fuses but the motor starter is resetable and is designed to use with motors and their large current spike on startup. Using a DIN rail makes mounting easy. But package them up (box, etc) so you are not exposed to any hazardous voltages (same goes for VFD's that are not NEMA 4).

But do not think that I can just get a 1hp RPC for my 1 HP mill motor and avoid current protection. You really need the RPC a bit oversized. I had a 1hp RPC one that could not even start a unloaded 1HP mill motor.

 

[Thumper68]

So in your mill tooling thread you ask for tool recommendations. Can we assume that you now have this mill in your possession?

lg
no neat sig line

Not yet I will find out Tuesday night if I can make the deal or not.

 

[Thumper68]

I got the mill, now to get it home and wired up, I ordered a AR05 rotary phase converter from American Rotary, they were very helpful in setting me up with the converter I need to run all the 3ph stuff in the shop.

I read through the pdf on setting it up and all the recommendations therein. After doing so I came to the conclusion that I am not qualified to do the wiring, so I got a recommendation from a friend for a electrician and he is coming out Friday morning to look everything over and give me a bid.