Bought myself a mini lathe..

NYECOGunsmith

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What does the fine lettering on the side of the drill chuck say, usually it will tell you the gripping range of the chuck AND if it is not an integral shank chuck, it will tell you the taper of the shank, like a JT3, MT2, etc. and then like TJK said, remove the screw (cheaper chucks don't have the screw by the way) and a BRASS punch and hammer to drift it out, supporting the back side of the chuck on a block of wood that you drilled a hole through large enough to let the shank pass through, and then rig up a means of catching the shank so it doesn't fall on something hard and get damaged, you might want to use it later.
Chuck removal wedges are also available, they are used in pairs, and for some tapers, pairs must be stacked in order to get a taper separated.

As for the DRO. I prefer to have all axis covered by it, for really precise work the DRO is hard to beat as you don't have to worry about the "take up" ? Back Lash / Wink in the travel of any axis you are moving, the DRO will only show actual movement of that axis, whereas the dials on the handles will show movement before the table or carriage or cross feed or compound or whatever actually starts to move, that's the wink in the gear train being taken up, and it will vary with age and wear. The DRO will always be accurate.

I have DRO's on the lathe on the carriage, cross feed and compound, and on the tail stock ram as well, because some of the gunsmithing work I used to do and still do occasionally, I like to keep the tolerance to a thou, and half a thou if possible, the DRO makes that a lot easier.

Those adjustable parallels are as TJK said, very handy for measuring slot widths, setting up a sine bar (although I usually use precision gauge blocks for that, the adj parallels are good for fast, rough work in that usage), and in pairs can be used in a pinch as parallels to elevate work on the mill vise, set things up in the jaws of a chuck that are too small to seat down against a jaw step, etc. Very handy tools.

You're making out like a bandit here!
 

TexasJackKin

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NYCOGunsmith, I've got to tell you, I know a lot about a limited number of subjects, and a limited amount about a lot of subjects, But you Sir, seem to have a near encyclopedic knowledge about ......Well, I haven't seen you stumpted, I must tip my hat to you Sir, very impressive knowledge base! After a lifetime of machine work, and Tool $ Die work, I've learned more than a few things reading your posts, both in this thread, and others you have participated in. I always look forward the reading your posts.
 

NYECOGunsmith

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Thanks TJK, but you have to remember, I am just a lowly A.I. program, athough according to Gullwing, I am a very,very,very old A.I. program.
One of the two old timers who taught me the gunsmiths trade was a retired master tool and die maker, and master machinist, he tried to teach me those trades as well.

I suspect your 40 years of working in those trades probably outstrips my knowledge and experience in those areas by a factor of 10 to the 40th power.

I get by, that's about it, for most machining projects which are not firearms related.
 

NYECOGunsmith

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That's because it IS EASY, after a few hours of practice and watching those videos.
You have at least two real machinists here on the forum, plus me, if you have questions, ASK.
What are you finding hard to do ?
 

Pcmaker

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I'm trying to get a smooth finish on the parts that I'm milling and facing, but the tooling marks are very visible despite me using 4 flute hss end mills. Also, I'm way off on the expected diameter when I'm turning steel. About .015 off. Not to mention a not so smooth surface. Getting better at it, though.
 

TexasJackKin

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How much are you leaving for the final cut? Keep in mind, some cross feed dials are calibrated for diameter, and some are calibrated for tool moment. (Move the tool in .010 will reduce the diameter by .020.) Some tool grind/material/ combinations won't give you a good finish with a light finish cut. (There's a bunch of other factors, if I'm not sure about a particular material, I'll make a practice finish cut, with my best guess about feeds and speeds, before I get to the final diameter)

With the end mill, most of the time, you can get the best finish with a light climb cut, on the final pass, but you need to be careful. The mill will want to "auto feed" by yanking the slop out of the feed screw, and that can create a bit of excitement! So, just a few thousandths on that last pass, and keep the chips blown out of the cut.

If your just milling the surface (not a pocket or slot) make or buy yourself a fly cutter, it's easy to get very nice finishes with a fly cutter, just make sure your head is trammed.
 
Steve
I fried the VFD Friday. Got a new one coming in today, yes Amazon gets the USPS to deliver on Sunday.
I checked all the connections and all seems to be O.K. I have a question as to how you operate yours, do you use the VFD to start/stop and adjust the speed or just provide current and use your on/off-rev/fwd handle as usual. My manual says not to have any magnetic switches in feed line or between 3 phase output and the motor. The power, 3 phase output, goes in and up to the fwd/rev lever and then down to the motor and i have no idea if this switch is magnetic. Any thoughts?

jimf5
 

NYECOGunsmith

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Hi Jim.
I feed the VFD output to the lathe and the mill directly, but going through their original drum type (mechanical contact) on/off Forward/Reverse switches, no problems. I turn the VFD on, set it to run and forward , then turn the lathe or mill on with their own drum switch, no magnetic switch anywhere there.
Magnetic switches are designed to prevent the machine starting up again AFTER an unexpected power outage, to protect the operator. It is possible your lathe has had one installed on it.

Some VFD's require you to use them as the start and stop, and wire around the switch on the lathe or mill , this is generally so you can use the VFD to ramp up to speed, coast, or brake, three functions not really needed in a home shop, but handy in a production shop. My VFD doesn't require that, it can be set up either way, so I just went with it providing 3 phase power directly to the machines and use their original motor control switches for functionality.

Saves having to walk away from either machine to start or stop the motor, at least in my set up.

Installing the VFD per its manual, and operating it and the machine attached to it per the manuals instructions should be pretty bullet proof, so either your lathe does have a mag switch, or the VFD just experienced a very early end of life failure.

Since you made some chips with the lathe earlier, I would have to guess no mag switch, and you wired it up correctly, so early end of life seems like the remaining choice.

What were you doing when the magic smoke came out of the VFD? Can you describe sequence of events leading up to that moment?
 

NYECOGunsmith

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How much are you leaving for the final cut? Keep in mind, some cross feed dials are calibrated for diameter, and some are calibrated for tool moment. (Move the tool in .010 will reduce the diameter by .020.) Some tool grind/material/ combinations won't give you a good finish with a light finish cut. (There's a bunch of other factors, if I'm not sure about a particular material, I'll make a practice finish cut, with my best guess about feeds and speeds, before I get to the final diameter)

With the end mill, most of the time, you can get the best finish with a light climb cut, on the final pass, but you need to be careful. The mill will want to "auto feed" by yanking the slop out of the feed screw, and that can create a bit of excitement! So, just a few thousandths on that last pass, and keep the chips blown out of the cut.

If your just milling the surface (not a pocket or slot) make or buy yourself a fly cutter, it's easy to get very nice finishes with a fly cutter, just make sure your head is trammed.
Ditto the above, plus....on the lathe, were you using a HSS tool bit, or the indexable insert carbide ones? It's often tough to get a decent finish with an insert when taking a fine finish pass, HSS excels at this (as long as it is sharp, and ground to the proper geometry for the application that is), and you may be experiencing spring back, depending on the diameter and alloy of the work piece.
Spring back is where the tool bit pushes or bows the workpiece away from the lathe's center line during the pass and while more prevalent in a hogging (deeper depth of cut) cut than a finish pass, it can occur anytime and I have found over the years it happens more often with an carbide insert tool bit than a HSS one, there is a bit more friction between the cutting edge of the carbide than there is with a well ground and polished HSS tool bit. At least that's my theory on it.

As for the milling, speed, feed, depth of cut, chip load, cutter geometry (does the 4 flute end mill have a radius edge ( not a ball nose, but a slightly radiused 90° edge) or is it ground to cut a true square shoulder on the end, and is it center cutting?

Climb milling is where your are feeding the workpiece WITH the rotation of the cutter. For example, if you were to look down from the top of the machine's spindle and the cutter is rotating clockwise (right hand cutter in other words) and you start the work piece from the right side and feed it towards your left, it is going WITH the cutting flutes on the end mill, and thus the cutter wants to grab it and PULL or sling it out the left side.
Kind of like a baseball pitching machine works, pinching the ball between two spinning rollers.
On the mill, you are pinching the work piece between the spinning end mill and the jaw of the vise.

Conventional milling is where you feed the workpiece AGAINST the direction the cutting flutes are spinning. So in that manner you would feed the workpiece from the LEFT towards your right, and the cutter is trying to PUSH it back to the left.

The above two scenarios apply to side milling with an end mill. If you are surface milling with one (top surface of the workpiece as mounted in the vise) you would have to be using a center cutting end mill, otherwise you would be burnishing/ frictioning the metal away, not cutting it and you would overheat the end mill and ruin it in seconds.
But if you are using a center cutting end mill to surface the work piece, then the direction of feed becomes moot, and no matter which direction you feed from X=, X-, Y+, Y-, the cutting is conventional milling for one quarter of a rotation, and climbing milling the other quarter in whatever direction you are feeding from / towards and this happens twice in one revolution of the cutter.

Surfacing with a center cutting end mill will leave lots of tool marks, as unless the workpiece is the same width, or slightly smaller than the diameter of the center cutting end mill being used, you will have overlap marks if nothing else, where you make multiple passes to surface the entire width of the piece. And since the endmill is smaller that the workpiece, the arc lines it leaves behind, even in a fine finish cut, are more readily visible to the human eye, and more easily detected with a fingernail drag test as well.

With a properly ground and sharpened fly cutter that spans the entire width of the workpiece in one half revolution, you get conventional and climb milling in quarters just as you do with the center cutting end mill, but because the fly cutter is ground to be a single point of contact and produces a longer arc than the cutting edge on the center cutting end mill does, the pattern is less discernable to the eye or fingernail when you get the speed and feed and depth of cut and chip load right for it compared to the center cutting end mill that is.

A Face mill is like a bunch of fly cutters following one another, but most of them are cemented carbide, or carbide inserts, so again getting a fine finish is tricky in some alloys.
There are still some face mils around that take multiple HSS lathe tool bits, or HSS inserts, and they can give a good finish in most any alloy.

Also, if you are face, fly or end mill surfacing a surface that has any gaps in it (an interrupted cut, same as turning on a lathe where the workpiece has a hole or slot in it that the tool bit has to skip or jump over once per revolution) you will not get all that great a finish, there will be burrs at the leading and trailing edges of the hole/slot/gap that will have to be removed by hand.

And as TJK said, if you use the fly cutter (or an endmill) to surface a piece, make sure the head is trammed to the table and that the workpiece is held firmly DOWN against the vise bed ways or the table.
If the head isn't in Tram, then you will get an angled cut with any tool in the spindle, because the tool bit / spindle are tipped out of a perfect 90° perpendicular to the table so the leading edge of the tool bit in the direction in which the spindle tilts closer to the table, will cut deeper than the trailing edge. And you want them flat so that they cut to the same depth.
 
Steve
Thanks for the reply. This unit was soft wired up to test and per the reviews i read it shuts off but for some reason the cooling fan runs all the time.
All worked well so when i hard wired it up i put two on/off switches in before the converter, one on each 110 volt feed. Everything worked fine for three or four days. Friday a friend came over and wanted to see it run. I flipped the two switches and put the lever to FWD on the lathe and no go.
Turned the HTZ nob on the converter up to 60 HTZ from 40 HTZ it sparked and the puff of death smoke came out.
Checked all the connections for shorts all good. I followed all start up instructions. I just received the new unit so I will know more in a few hours.
jim
 

NYECOGunsmith

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I wired my VFD with a single 220 double pole switch that simultaneously energizes both 120 volt input legs into the VFD.

I suppose it's possible if one of your two input switches didn't actually transfer, or had a high resistance connection, the loss of that leg could cause a problem with the VFD.
 
Hi All:
All is well in lathe land. I wired it up without the on/off switches to eliminate one possible problem and got it running. One problem still exists that is to run the machine i put the lever to FWD, push RUN on the converter, and slowly ramp up to 60 HTZ. The manual with the converter is mostly for programming and is a little above my mental capacity. In a previous life (when i worked for a living) i was a Manufacturing Engineer and not a lot of electrical problems to deal with.
UPDATE: just got your reply about single 220 double pole switch. I now have tomorrows project. Thanks
Too hot to work in the garage so will settle in with the VDF manual
jim
 

NYECOGunsmith

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Jim, what is the make and model of your VFD, if I can find the manual online I will read thru it to see if I can answer any questions you have, I have a degree in electronics, although it is 50 years old! I may be able to make heads or tails out of it for you.

On my VFD, I leave it set to 60 Hertz, unless I need to have either the lathe or mill run slower or faster than they will at 60 Hertz, I just hit the Run, then Forward buttons on the VFD after it powers up all the way, and from that point on I just use the on/off switch on the machine to start or stop it.
 
Here is the info
LAPOND SVD-ES Single Phase VFD Drive VFD Inverter Professional Variable Frequency Drive 2.2KW 3HP 220V 10A for Spindle Motor Speed Control (VFD-2.2KW)
If you can not find one i have two now i can get to you
jim
 

NYECOGunsmith

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OK, looks like they don't want you to use a magnetic contact switch as the power control switch on the INPUT to the VFD, as it will shorten the life of the VFD it says.
Can't see how it would do that, unless they are worried about interfering/conflicting magnetic fields.
WAIT A MINUTE!!
Then later on it says that IT IS recommended to install a magnetic contactor on the input to the VFD! To protect the motor and operator in the even of a power failure. Sheese, wish they would make up their minds!
Manual was obviously translated from Chinese, judging by the grammar and syntax.

I think if it were mine I would wire the input through a 220 Volt, double pole switch, then into the VFD. From the output terminals I would go to input terminals for the lathe, and let the lathe power on and off switch be part of that circuit. I can see no reason why using the machine's power switch would cause a problem for the VFD, at least not from the wiring diagram or verbiage anyway. But that's just me, you will have to decide for yourself what to do.

Maybe a call to LAPOND tech support if they have one is in order.

If wired as above, then when you go to use it, turn on the 220 VAC switch, let the VFD power up, give it 30 seconds to 60 seconds to run through any internal diagnostics (mine takes about 30 seconds) then hit the run and then the forward switch, and you should be ready to make chips.
Mine has been running like that for 13 years with no issues.

I can't find anything that says on this model that you have to select (as you can on some brands) remote control where you would wire the output of the VFD directly to the machine motor, bypassing the machine's power on/off/forward/reverse switch, and controlling that with a low voltage circuit using low voltage shielded wire and a ON-OFF-ON type of switch to tell the VFD to supply power to the motor and in what direction.

I have had units like that the past, but my current Yaskawa, made in Japan, came set up for direct control by the machine's original switch and I left it that way.

With any of the VFD's I have had, I didn't ramp up to 60 Hertz, left it set at 60 Hertz and started the motor and ran, there is no need to ramp up to it.
You alter the HERTZ to change the speed on a three phase motor, and you swap any two phase legs to reverse them, no need for ramping up or down except in a production shop where you would also be using the braking circuit (internal or add on feature on some) and braking resistor.

The braking circuit on most just removes the 3 Phase AC from the motor and then gives it a shot of pure DC voltage and current on two of the three legs to bring it to an instantaneous halt (if the voltage and current are high enough) or to slow it down at a given rate if the voltage and current are modulated and ramped up slowly.
 

TexasJackKin

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I've been following this closely, once we get moved AND SETTLED, I'll be stating to look for a Bridgeport Mill and something along the lines of a 14" lathe. And as I've said before, I know enough about electricity to know I'm not an electrician!
 

NYECOGunsmith

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I have an older brother who says all he needs to know about electricity is five things:

On
Off
Don't touch bare wires
Don't stand in puddle of water while doing the first two, and especially not if forced to touch number three, and finally.....
His little brother's (meaning me) phone number.....

Anything more complicated mechanically than a lug nut, or anything electronic or electrical he refers to me, saying what's the point of having a little brother with Masters degrees in electronics and mechanical engineering if you don't use him.

I keep telling him those degrees are over 50 years old, never really put to use, and we have advanced well beyond the wooden wheel, simple lever, and Leyden Jars that were cutting edge when I was trained.
 

NYECOGunsmith

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I've been following this closely, once we get moved AND SETTLED, I'll be stating to look for a Bridgeport Mill and something along the lines of a 14" lathe. And as I've said before, I know enough about electricity to know I'm not an electrician!
I have a Birmingham 14x40 18 speed gap bed lathe, and a Birmingham 9x49 variable speed mill, both with 3 hp 3 phase two speed motors. They are both made in Taiwan, but right out of the crates were ready to go, I found no sand in the headstock or anywhere in the beds or castings as is often the case with the Chinese machines.
Neither has ever given me a moments trouble or caused me to regret buying them. Both are equiped with Unique DROs.