Clausing 5904 vfd conversion pictures in dropbox

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In a previous thread started back on 12/28 I responded about the vfd conversion I'd recently done to a similar machine. I said I would post
some pictures, they are in the dropbox starting at 5904_vfd.txt. Please excuse the poor photography. There are caption blurbs for each jpg in the .txt file.
Regards Paul
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All
In a previous thread started back on 12/28 I responded about the vfd conversion I'd recently done to a similar machine. I said I would post some pictures, they are in the dropbox starting at 5904_vfd.txt. Please excuse the poor photography. There are caption blurbs for each jpg in the .txt file.
Regard Paul
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Paul wrote:

Aaaargh, I just noticed the stupid text file didn't wrap at 80 characters. I sent a hopefully fixed one but it will probably take awhile for it to get updated as it has the same filename as the original and thus will require manual intervention. Sorry for an inconvenience.
Paul
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I got the unwrapped one a minute ago.
I would suggest copying the explanatory text for your recent email on the 5914 into the 5904_vfd.txt file, for completeness.
Thanks for the posting.
Joe Gwinn
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    Nice (and useful) photos. Among other things they show how different the 5900 series is from my 5418.

    I downloaded the unfolded one and discovered another problem as well in the process of folding the lines.
    Several of the original lines appear to have been truncated -- presumably by the software which unpacks the .txt file from the e-mail. Examples follow (I've trimmed out the middle lines, keeping the first line for identification, and the last line for where the truncation occurred.):
=====================================================================5904_vfd_05.jpg shows the parts all assembled and ready to be installed.
    [ ... ]
other features such as the base cabinet lower cover m ==================================================================== =====================================================================5904_vfd_08.jpg shows the bracket and motor mounted in the base cabinet
    [ ... ]
will get into the control cabinet via a short piece of ==================================================================== =====================================================================5904_vfd_11.jpg shows the vfd enclosure mounting from a different angle,
    [ ... ]
kw (3hp) Mitsubishi 230 volt single phase input in a nic ====================================================================    This one may be truncated. No punctuation at the end of the     last sentence, but the final word appears intact. =====================================================================5904_vfd_15.jpg shows the speed pot enclosure and mounting parts. The
    [ ... ]
aluminum and will be held into the original speed control boss ==================================================================== =====================================================================5904_vfd_16.jpg shows the speed pot and enclosure mounted to the top of
    [ ... ]
and a temporary hand printed legend plate for speeds in bot ====================================================================    If you need, I'll try to phone Steve to tell him that it needs attention, since he is local.
    Good Luck,         DoN.
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DoN. Nichols wrote:

Hey DoN
I did send a repaired version after I saw the original munged up copy, that's what I get for using an unfamiliar editor. According to the dropbox information, files received with an already used file name go into some sort of limbo land awaiting human intervention.
A call on my behalf would be appreciated!
Thanks Paul
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    [ ... ]

    Turns out that it was necessary. It seems that you sent each file separately, instead of all as attachments to a single e-mail, and he had not gotten to the notifications on that before you sent the update, so he made the mistaken assumption that they all were different parts and put all of the e-mails in the processed folder.
    Anyway -- it is now fixed.
    I suspect that your finish problems pre VFD were coming in part from the somewhat frayed belt which you have replaced.
    I like the idea of putting a tach display into the project box with the speed control pot -- and a panic button is not a bad thing to add, too. I would drive the tach display from a magnetic impulse pickup counting the teeth on the bull gear. That should give you pulses close enough together so you don't have to wait for a full rotation or two at the slower speeds before you get a valid reading.
    When I put a VFD and three phase motor in my 5418 I won't have to do as much work. I'll keep the five-step pulleys for when I need really slow operation at high torque, or really fast operation at low torque, with most changes being done with the speed control pot.
    I presume that the project box was one of the die-cast zinc ones? They can be quite useful -- even though Frys is a long way from here. :-) (But -- there are local vendors who carry them.)
    Enjoy,         DoN.
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DoN. Nichols wrote:

Thanks DoN, it helps to know people in high places:) Actually the first email had all the files but instead of .txt the name was _txt and it never made it into the directory. I then sent a second email with just the txt file, this time named .txt, it did show up but the formating was hosed. The third email had the repaired file but it had the same name as #2...but all is OK now.

The belt I suspect was the much thicker belt that was between the motor and countershaft on the variable cone pulleys, but it could have been the final countershaft to spindle cogged timing belt.

This VFD has an output for a tach, scaled either for a 1ma meter or some strange 8 volt square wave signal. Your idea of a tach pickup on the spindle is better as it's actual feedback and not what the drive merely thinks the speed is based on it's output.

That's one reason I went with a higher horsepower motor, and the thing I think allot of people don't take into account when going the VFD route. The motor being a basically constant torque device has much lower HP at lower speeds. That is one advantage of belts or gears for speed reduction.
The pot is scaled to give 280 to 2000 RPM in straight gear, and back gear divides that by 7, this basically replicates the original speed ranges produced by the varidrive.

Yes, some sort of zinc alloy, actually a nice example of the diecasting art, thin sections yet nice and straight, and a good surface finish as well. The other impressive thing was the 6 cover screws were not self tapping but tapped holes.
Fry's built a store in my area 2 or 3 years ago, it's about a 30 minute drive but if we're in the area anyway I usually stop.
Regards Paul

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From the pics, the VFD appears to be a Mitsubishi FR-A5xx. A nice feature of these drives is that it's easy to remote the operator panel with an RJ-45 network cable. The display can be scaled to display machine speed, and if the drive is running in flux vector mode (which you should definitely be doing since you want full torque at low RPMs), the display is based on what the drive is sensing from the motor, not simply output frequency. Of course you'd have to do the mental math to account for the speed reduction when in backgear.
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Ned Simmons wrote:

Hello Ned
It's a FR-A024, unfortunately no RJ-45 jack. There is a port on the front that the programmer/operator interface plugs onto when mounted on the drive, or a remote operator interface can use the port via an oddball cable, but not both at the same time, not very handy. Also the interconnect cable ends are large enough not to fit through 1/2 inch sealtight. Of course none of these problems are show stoppers, they just make things more difficult:)
I originally had the flux vector feature enabled and experienced obvious speed hunting under load, I disabled that and one can hear the rpm drop when taking a heavy cut but they hold steady. I'd like to employ the vector feature but I think more experimenting may be in order.
Regards Paul
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    [ ... ]

    :-)
    And yes -- Steve does know that longer lines (over 256 characters, IIRC) get truncated when being extracted. Another reason for folding the lines before sending. (Out of curiosity -- what editor was it which did you in?

    O.K.
    Obviously, I would need to sense the spindle in some way, since I am retaining the step pulleys. The alternative would be a standard meter movement and drawing multiple scales on it. :-)

    Certainly I will be upping the HP -- from 1.5 HP to 2HP in the lathe. Note that you would have an effective gain in HP even if you had kept the same motor HP -- because those vari-speed pulleys do consume a lot of extra HP. This is why the vari-speed J-heads on Bridgeports are 2HP, while the step pulleys are 1 HP or 1.5 HP.

    O.K. This is reasonable -- but I'm looking forward to being able to go even lower in spindle speed -- for when coarse threading to a shoulder. :-) (Though my reaction time is pretty good so far when doing that.)

    Yep -- sounds like what I have used in various sizes.

    I think of Fry's as being somewhere in California. Is that where you are?
    Enjoy,         DoN.
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DoN. Nichols wrote:

KWrite 4.1, I usually use JOE but this time I was in GUI land and KWrite was there. As I'd never used it since the last time I upgraded OS versions it had never been configured. The default is line wrap off, I guess that's a sane choice for an editor that will probably be used to write code...i guess. The lines wrapped just fine in the editor on the screen but I guess the file lacked <cr/lf>s

I'd considered that, but it's not much more accurate than the cheesy paper scale I made and installed in back of the speed knob. I plan to check its accuracy with a handheld tach and then get a permanent one engraved at the local sign place. Actually, I rarely worry about actual rpm, I just set the speed to what 'seems right' but it is nice to have a rough idea what that speed is. An actual speed display falls under the 'gee whiz' category for now. A braking resistor would seem more urgent. By the way has anybody ohmed out an electric stove element lately? Somebody here tossed that idea out in another thread.

True enough but getting rid of the vari-drive losses only partially makes up for the lower power at lower RPM's with the VFD

I did have occasion to thread to a shoulder after the VFD install (5/8-11, so there were plenty off passes) and was able to end up with just one leadout groove only just slightly wider than the thread:)

Actually I'm near Chicago, Fry's is expanding. They started in California, the first one I was ever in was in Houston, and now this one opened nearby a few years ago.
Regards Paul

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    [ ... ]

    O.K. I normally use jove -- unless I need to deal with extra-long lines, in which case I switch to emacs which will accept pathologically long lines with no complaints.
    Jove defaults to no line wrap (again a programming editor) but the .joverc file can be configured to look at the filename (or part of it) and change settings. I have mine configured so if the file has an extension of ".txt", or matches the file name patterns used by either my newsreader or e-mail client it will switch on auto-fill mode. It also turns on such things as the automatic acronym expansion (which I use to correct my most common typos) and various other features.
    [ ... ]

    Agreed.
    Hmm ... have you never used photosensitive anodized aluminum plates? Take black anodized aluminum plates, coat with a photoresist which can handle strong alkalis (the old Kodak photoresists (KPR) were good, the Kepco positive photoresists would dissolve in alkalis). Anyway -- make a layout, make a negative from it (Kodalith Ortho is a good material which gives plenty of contrast), expose to UV light through the negative, develop (in trichlor for the KPR), then gently scrub with cotton swabs soaked in strong NaOH solution, which will dissolve the anodize and let the dye go, and you have very nice looking panels -- complete with white areas which can accept serial number stamps and the like.
    These used to be available as kits from Allied electronics and Newark -- and may still be available. I wish that I could remember the name of the kits.
    I know that Kodak has stopped making their photoresist, but I think that others still make the same product, since it is commonly used for making printed circuit boards. For even application, you need a spinner. A hollow-shaft DC motor with speed control, a coupling to a vacuum source on the bottom end, a flat chuck on the top with radial grooves to spread the vacuum and an O-ring near the OD. You put some photoresist on the center, then spin it up to spread it over the whole upper surface, and send the excess flying off to the edge of the bowl. Make sure that you add a vacuum sensor to prevent spinning up when the vacuum is not present. Obviously, store-bought panels are better for labels, but if you want to make a rigid anodized front panel with nice markings (such as for some of the modular test equipment bays), it is nice to be able to apply this to a panel already cut to size, punched, and anodized so the anodize wraps to the edges. (And, you'll probably want to apply more resist of some form to the edges after exposure and developing.

    Agreed.
    Certainly if you want to reverse frequently -- such as for tapping with a bed turret and a releasing tap holder.

    We use gas, so I can't check one here. Note that the value of the resistance in such tends to vary with the temperature. It is much lower when the element is at room temperature, and increases with temperature -- just as a light bulb filament. Unless you are reversing *very* frequently, the cold resistance is probably good enough to measure. If you want the hot resistance -- best to just work from the wattage of the element (and the voltage at which it gets that wattage), or to measure both voltage and current when it is hot.
    [ ... ]

    Understood -- which is why I am retaining the step pulleys, so I can get that serious torque when I need it.

    I usually use the threading tool to make the runout groove -- to full depth, and followed by manually moving it from side to side before actually starting to cut the threads. The actual width depends on speed and pitch.
    [ ... ]

    Hmm ... this may give hope that there will be one here in the East coast someday?
    Enjoy,         DoN.
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DoN. Nichols wrote: <<<< some misc. snippage >>>>

I started using Joe back when I first started with Linux and Emacs took forever to load just to make a simple edit to a config file, this was back in '95 and Linux kernel 1.1.59, Later I was involved in something called LRP (Linux Router Project) which was basically a small footprint distro loaded to a RAM drive via 3.5 floppy, usually formatted larger than 1.44 mgs, that setup a NATing router on something like a 486 class machine, this was before all the usual suspects were making 'Internet routers'. Joe's small footprint was especially helpfull then.
I believe that project is dormant at this time but even then things were possible that you don't get with todays home class routers.

<<<< snip >>>>>

That's not a bad idea, tooling up for just this small job might be prohibitive, but now that I think of it there is a local printer that used to do silkscreens and etched aluminum data plates of a drive company I worked at long long ago. I should see if they still survive.
<<<<< snip >>>>>

Reversing is only part of it, one of the features on this lathe was a mechanical clutch and brake actuated via a lever on the right side of the apron (don't know if yours has that). I'd feel better with a spindle that comes to a rapid stop when told to do so, not only for impending crashes but for errant stringy chips interfacing with body parts, or body parts interfering with spindles, chuck, work, etc :)

Gas stove here also, and I also figured cold resistance would be fine considering the duty cycle and amount of power dumped into it, it's not like its continuous are anything.

<<<<< snip >>>>>

That's basically my MO as well, even if I kill the power, letting the lathe coast to a stop and pulling the chuck the last half a turn by hand:)

Fry's (at least the one here) has everything from electronic components to computer parts to TV's, washers, dryers and everything else consumer electronics. I don't know if I'd exactly call it Mecca, but definitely worth having in the area.
Regards Paul
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    [ ... ]

    O.K. Jove is also significantly smaller than emacs -- but with a similar command set until you get into the lisp enhanced stuff in emacs. On Solaris 10, here is what I find:
=====================================================================-rwxr-xr-x 1 root staff    275080    Mar 23 1999 /usr/local/bin/jove* -r-xr-xr-x 2 root bin    6551000 Apr 27 2007 /opt/sfw/bin/emacs* ====================================================================    And jove is that much smaller while its executable is not stripped, while that of emacs is stripped. :-)
=====================================================================/usr/local/bin/jove:     ELF 32-bit MSB executable SPARC Version 1,     dynamically linked, not stripped
/opt/sfw/bin/emacs:     ELF 32-bit MSB executable SPARC Version 1,     dynamically linked, stripped ====================================================================> I believe that project is dormant at this time but even then things were

    Hmm ... I wonder how it compares with the stuff which you can do with pf (Packet Filter) on OpenBSD when running it as a firewall/router?
    [ ... ]

    [ ... ]

    A lot of that tooling is only necessary if you are going to photosensitize your own panels. If the kits are still available, that will be a lot less resource intensive. You'll need:
1)    A UV source for exposing (though you can get away with     photofloods and much longer exposure times.
2)    An amber light bulb (bug-free type) for handling the     photosensitized plates. (They aren't *that* sensitive. :-)
3)    Someplace fairly dark which will carry off the fumes of the     trichlor developer.
4)    A glass tray for doing the etching in, since I'm not sure how     well plastic photo trays will deal with the NaOH, and they     *certainly* won't deal with the trichlor developer well at all.
5)    Either a drawing package and a B&W laser printer for making the     negatives directly on mylar, or an enlarger and Kodalith Ortho     (or simply a 4x5 camera for making smaller data plates and     nameplates, as I have done at home in the past.
    That should be enough as long as you are working with pre-coated boards.
    I even used it for making a property label for my concertina case, calling it an:
    AN/PNT 47T
    (And -- if you have the standard for the AN numbers available, that translates to:
    P in first position:     Man or pack portable
    N in second:        Sound in air
    T in third:        Generator
    And the instrument was a 47-key treble, hence the last part, which was stamped into a white (bare aluminum) area on the plate, so it could be set up for anyone's instrument.
    It also had a place for the owner's name to be stamped.

    O.K. So far, I have the single-phase motor and have had to learn to do without rapid spindle stops. :-) Some of these days, I'm going to put the three-phase motor in, and wire the VFD to start/stop/reverse from the drum switch -- plus a tiny holder below that for the speed pot (rescued from an old Bridgeport BOSS-3 control pod. A nice Allen-Bradley pot behind a knob and mount which looks like the switches on the same. (Hmm ... I could use one of those switches to tell it which pulley step the belt is on, if I need that for scaling the tach. :-)

    [ ... ]

    Agreed. But I just had to mention that. :-)

    O.K. I do it under power, and just pop out the half-nuts at the right time. (At least until I have to do metric threads on that machine. :-) *There* is where really slow operation and quick reversing will be helpful.
    [ ... ]

    [ ... ]

    O.K. I think that Fry's was one of the places which I hit while visiting my sister in the California area -- though Weird Stuff was more fun. :-)
    Enjoy,         DoN.
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" giant snip -------------

for what it's worth, when I put a VFD on my 12 inch Logan/Powermatic, I added an RPM display as well- I used a little (3/16 diameter) proximity sensor that counted teeth on a convenient gear affixed to the spindle, then set the display to divide the proper number to display in true RPM - works great - I removed the large switche that had been the forward/reverse switch, replaced it with a small toggle switch, and installed the RPM display where the previous fwd/reverse switch had been.
This all seems pretty obvious to me, but if anyone really needs pictures and stuff, ask and tell me what part you need photos of and I'll take some and put them in the drop box
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DoN. Nichols wrote:

DoN
Here's the .txt file as it should have appeared (don't want to keep you in suspense)!
------------------------------------ 5904_vfd.txt 010408 PDB
5904_vfd_01.jpg shows the lathe base cabinet with all the old drive parts removed, didn't think to take a picture of it before I started. The enclosure to the left is the box with the VFD mounted to the back side of the lathe.
5904_vfd_03.jpg shows the new mounting bracket parts ready to assemble. All the holes and slots were done on the Bridgeport the pieces are sitting on. Nothing was scribed and punched, all layout was done 'by the dials' ala poor man's jig bore.
5904_vfd_05.jpg shows the parts all assembled and ready to be installed. 9 inch channel was used for the motor base, the side pieces are 3x3x1/4 inch angle. Some milling was required for clearance of other features such as the base cabinet lower cover mounting studs. The two tapped holes on the back of the base are for brackets for forced cooling fans and a braking resistor (future).
5904_vfd_08.jpg shows the bracket and motor mounted in the base cabinet ready to go. The new motor location is about where the original countershaft/clutch/brake assembly mounted. The motor T leads will get into the control cabinet via a short piece of sealtight, the fitting is visable just below the motor pulley in the back of the base cabinet. The sealtight coming from the control cabinet goes up to the original drum switch which now is wired to the vfd's forward and reverse inputs. The red wires visable are the temporarily connected speed control pot wiring.
5904_vfd_09.jpg is a front view of the new motor etc. The old motor and brackets are visable in the background on the left. I bought a new belt even though it turns out I could have made the original belt work but it was starting to show it's age.
5904_vfd_11.jpg shows the vfd enclosure mounting from a different angle, I couldn't get much closer due to a wall just to the right. I bought this vfd from a fellow RCM guy (thanks Iggy), its a 2.2 kw (3hp) Mitsubishi 230 volt single phase input in a nice Rital enclosure complete with a lockable disconnect, local/remote selector, pilot light, etc. The ironic thing is I have 3 phase at this shop.
5904_vfd_15.jpg shows the speed pot enclosure and mounting parts. The die cast enclosure was a project box from Fry's, very nicely made and easy to machine. The large disc was machined from aluminum and will be held into the original speed control boss on the top backside of the headstock. Bolt and bushing are next to it.
5904_vfd_16.jpg shows the speed pot and enclosure mounted to the top of the headstock using the mounting boss for the original speed adjuster. I've since made a nice large brass knob for the pot and a temporary hand printed legend plate for speeds in both straight and back gear. The extra space in the box is for future use, maybe a digital speed display or a big E-stop button or a jog button...time will tell. -----------------------------------------------
Paul
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    [ ... ]

    Thanks -- but I called Steve and downloaded the replacement before reaching this article. :-)
    BTW -- he is quite pleased to see something better than a two-word ".txt" file these days.
    Enjoy,         DoN.
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Since I like clausings,
http://metalworking.com/dropbox/5904_vfd.txt
http://metalworking.com/dropbox/5904_vfd_01.jpg
http://metalworking.com/dropbox/5904_vfd_03.jpg
http://metalworking.com/dropbox/5904_vfd_05.jpg
http://metalworking.com/dropbox/5904_vfd_08.jpg
http://metalworking.com/dropbox/5904_vfd_09.jpg
http://metalworking.com/dropbox/5904_vfd_11.jpg
http://metalworking.com/dropbox/5904_vfd_15.jpg
http://metalworking.com/dropbox/5904_vfd_16.jpg
Wes
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Wes wrote:

Thanks Wes
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