# G0709 for mcdanlj



## mcdanlj (Nov 3, 2018)

As I have been preparing my shop for my PM-30, I started thinking about a larger lathe, too. I started looking at various 1340s and 1440s and thinking about maybe a few years out. Then, just to see what the local market looked like, I glanced at CL—and saw that someone local had a reasonable deal on a G0709 with only a few years under its belt. So much for "a few years out..." The main thing it's missing for me are DROs. The DROs on my PM-30 seem reasonable, so PM's DRO kits are certainly an option.

Today, with the help of two dedicated and wonderful friends, I moved it into my shop!

I think I've read all the G0709 threads on this forum to prepare, so hopefully I'm set to get started. When I want more variety in speed, or better surface finish, or am bored, I may consider a 3Ø with VFD conversion. I've been looking at the schematics and it doesn't look like it would be super hard, and in fact would probably make the foot brake even more effective as a bonus.


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## mksj (Nov 4, 2018)

The G0709 is definitely a very nice lathe, especially in good shape and just a few year old. A proper VFD conversion for a single phase lathe is a bit more complicated then you may anticipate, when a VFD is used, typically it is either used for braking or the mechanical foot brake is used but not both. They will fight each other as the VFD wants to brake the machine in a prescribed fashion as setup in the parameter file, so jumping on the mechanical brake (which can stop the machine very quickly) the VFD may slow down that process if you were to use something like a 3 second stopping time. What is typically done is to change the foot brake electrical switch which shuts down the motor contactors, to a 2 pole version. One side is configured NC which connects to a power relay which shuts down the VFD run inputs, the other NO pole issues a free run command to the VFD so it does not brake. This allows you to use the mechanical brake independently of the VFD braking. I have built numerous lathe VFD systems this way.

Some lathe manufactures have done away with the mechanical brake altogether, they just used the foot brake to send an emergency stop command to the VFD, which will brake it at the fastest time possible without tripping it into an over voltage error.

You will need to look for a 3 phase motor that will fit the machine, I recommend what is known as a Vector/inverter motor which ate typically TENV type for this size machine. I have been using the Marathon BlackMax, Lincoln, and Baldor IDNM/ZDNM types.


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## BGHansen (Nov 4, 2018)

Congratulations on picking up a G0709. I've had mine just over 3 years with no issues other than what's been documented here. I have a TPACTools DRO on mine.

Bruce


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## mcdanlj (Nov 4, 2018)

mksj said:


> A proper VFD conversion for a single phase lathe is a bit more complicated then you may anticipate...



Thank you for all those specifics! How kind! I wasn't sure what would be faster; mechanical brake or emergency stop on a VFD with a properly-sized braking resistor. At any rate, I'll be investing in more tooling before I play with electrical upgrade. ☺ But now I can daydream more realistically!


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## mcdanlj (Nov 4, 2018)

BGHansen said:


> Congratulations on picking up a G0709. I've had mine just over 3 years with no issues other than what's been documented here. I have a TPACTools DRO on mine.



I'm trying to make sense of the differences between DRO packages out there. The set on my PM-30 seem good, so the Precision Matthews 8x40 lathe DRO package seems like a contender. The TPACTools DRO package looks pretty similar and sells for a similar price. The DROPros sets are $800-$1000 for the various 8x40 sets—so roughly twice the price. I haven't put together a spreadsheet to compare all the measurements from the provided drawings and probably I'll wait until I finish some work on my shop itself before I start seriously looking into it. In the meantime what factors have y'all considered for comparing the available DRO packages appropriate for a 14x40 lathe? Any other vendors I should be considering when I get there?


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## BGHansen (Nov 4, 2018)

Hi mcdanlj,

Here's the thread on the DRO I installed on my G0709 from TPACTools.  Frankly, haven't shopped for another DRO since I'm not currently looking for another one.  I chose TPAC originally for a mill 4 years ago because of a friend's recommendation.  Had a good experience with that one, so went with them for my G0709.

Bruce

https://www.hobby-machinist.com/threads/grizzly-g0709-lathe-dro-install.49902/


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## mcdanlj (Nov 10, 2018)

The manual says to make sure to use a rubber tip ball oiler to avoid damaging the ball oiler ports. On a google search, I see lots of folks saying that they have trouble finding rubber tipped ball oilers. I can find plastic junk with reviews saying "this broke on my first day using it" and things like that, but I haven't found what the manual tells me to use. Do folks mostly just use rubber hose over the tip of a metal oiler to make a seal without pushing the ball too far in? Also, I guess I could turn a tip from something soft like PE. Or does everyone ignore the manual?


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## mcdanlj (Nov 10, 2018)

In order to get the spindle better aligned with the ways, I'm having to take basically all the weight off the middle feet and use only the end feet to hold the lathe up. This doesn't make a lot of sense to me; why would there be six feet if I'm really only using four? But I'm sweeping a turning test bar and with runout around 1-2 tenths, I'm seeing 2-3 tenths per inch rise in the test bar towards the tail when I have similar weight on all four headstock feet. By transferring essentially all the headstock weight to the outside feet, I reduce that rise to 1-2 tenths per inch.

I think I saw the same thing indicating both against the top and bottom of the test bar, but I guess I could have misread. I suppose I should mic the test bar to make sure it has consistent diameter, not a gentle taper.

That's on the order of ~2 thou / foot error, which doesn't seem terrible. Is it a reasonable plan to let the lathe settle for a few days on four feet and then put some weight back on the middle feet for the long term? I'm still leveling it daily as it settles in.


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## Mitch Alsup (Nov 11, 2018)

mcdanlj said:


> The manual says to make sure to use a rubber tip ball oiler to avoid damaging the ball oiler ports.



I use an allen wrench (1/16") to push the balls open and a regular oiler and watch until a drop has run down into the oiler. I found this easier the trying to use the tip of the oiler to push on the ball.


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## Chipper5783 (Nov 11, 2018)

mcdanlj said:


> The manual says to make sure to use a rubber tip ball oiler to avoid damaging the ball oiler ports. On a google search, I see lots of folks saying that they have trouble finding rubber tipped ball oilers. I can find plastic junk with reviews saying "this broke on my first day using it" and things like that, but I haven't found what the manual tells me to use. Do folks mostly just use rubber hose over the tip of a metal oiler to make a seal without pushing the ball too far in? Also, I guess I could turn a tip from something soft like PE. Or does everyone ignore the manual?



 The Reilang oil gun is awesome.  The Reilang products are not cheap, but much cheaper than the result of not getting oil to where it needs to be.  There are any number of other options for delivering oil into the oil fittings (less expensive) - several of which I tried.  I would have been money and fussing ahead if I'd followed the advise of Forums similar to this one and got a quality oil gun (also called a "hand push oiler") right off the bat.

Regardless, make sure the oil is getting to where it needs to be.


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## mcdanlj (Nov 11, 2018)

Reilang seem not available in US based on google searches so far. I figure there has to be something available in the US that works, or we'd be reducing a lot of machines to scrap. I am for sure getting plenty of oil in place. I'm using a goldenrod with a metal tip. It's pretty obvious when oil is flowing and whether I have a good seal at the tip.


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## mcdanlj (Nov 13, 2018)

Letting the lathe rest mainly on the end feet for a few days reduced the variation a bit more. I'm now seeing less than 1 thou variation between centers and a little more unsupported at the tail end in the MT5/MT3 adapter, with the weight reasonably distributed across all six feet, and comfortably level. I think it's as good as I'm going to be able to measure consistently. With level settling in, and power fed to it, I finally made chips today. Started with a piece of aluminum scrap and an indexable carbide cutter. Happy with the finish quality available with power crossfeed!


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## mcdanlj (Nov 14, 2018)

@BGHansen — do you mind providing specs on the faceplate that came with your G0709? How thick is it? What's the real outside diameter? What's the inside diameter around the spindle?

Grizzly left the faceplate out of the order when they sold to the original owner, then stonewalled on a replacement, and that makes me not super excited about paying Grizzly $231 and waiting 3-6 months for their replacement parts to arrive from China.

5" D1-5 Threaded Black Plate for 5C Zero Set Adjustment Collet Chuck for $67.50 is the cheapest way I've found yet to source 6 D1-5 camlock studs; Grizzly wants $106 (+ shipping) just for a set of six D1-5 studs (not included with their faceplate), for which they project a 3-month wait.

Honestly the use I currently intend for a faceplate is to engage a dog to turn between centers, so I don't know that I need an 11" faceplate exactly; maybe I could just get Lathe Chuck Adapter Plate 10" D1-5 for $98.95 and mill short hold-down slots into the adapter plate and use it as a faceplate. The face would be about 3.3" from ID to OD and I don't intend to mount large heavy items on the faceplate.

Then if later I want a larger faceplate, it seems that McMaster will sell me a 1" long 12" round of cast iron for $82.70 + shipping. I could machine my own faceplate and use the studs from the adapter plate to mount it.

Am I crazy?


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## mcdanlj (Nov 15, 2018)

Or, a 12.5" OD 1.125" thick D1-5 adapter plate looks interesting for this purpose too.


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## BGHansen (Nov 15, 2018)

My Grizzly face plate came with my G0709.  It's 11" OD, 3/4" thick at the slot openings and 1/2" through through the face.  Also recommends not turning it over 750 RPMs.

Bruce


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## mcdanlj (Nov 21, 2018)

mcdanlj said:


> Or, a 12.5" OD 1.125" thick D1-5 adapter plate looks interesting for this purpose too.



$160 plus about $32 shipping included studs and shoulder stop bolts, shipped the day I ordered, and packed well, so I'm happy. I'm not going to be finishing it for a month or two; have to finish my shop project before I can get access to my grinder! ☺ But looks good so far!




The same seller on ebay also sells a 10” Chuck Adapter Plate D1-5 Spindle Mount 1-1/4” Thickness for $150 shipped, which in retrospect might have been a better idea. 12.5" on a 14" lathe is cutting it close!


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## mcdanlj (Nov 26, 2018)

I happened to see last night thta DROpros advertised a 50% off sale on DRO kits for Cyber Monday:




This seemed like a good super great deal, but when I called they said "oh, that's misleading" and then said that even though the web site wasn't specific, the discount applied only to one particular "absolute" kit that was only for mills. (The site did say limited to stock on hand, but they also make the point that they typically keep everything in stock!)

So  for misleading advertisements, but at least they admitted it and didn't try to sell me something that was not going to make me happy in the end or argue about it being misleading, so meh? I guess if they were honest that they were being misleading I should still keep them in mind for when I get a DRO setup? (EL700 vector summing would be  but $$$ and I'm honestly not sure about 1 micron scales on a grizzly anyway...)


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## mcdanlj (Nov 29, 2018)

According to the manual that came with my PM-30 mill's DRO, the SINO 3-axis DROs have a Y+Z summing mode in lathe mode for when the cross slide is aligned with the lathe axis, but no vector summing. A lot of the kit vendors don't have 3-axis lathe kits available. If I can be satisfied with 5 micron, banggood currently has a sale on a-la-carte 21mm thick 5 micron glass scales and DROs. That's thinner than tpactools advertises for their otherwise apparently identical kit, though for all I know it's really the same size measured by different people.

BigA ASD8 scales at 17mm thick are the thinnest glass scales I've seen so far, and are available in 1 micron, and it looks like the BigA DROs have Y+Z summing if I haven't got my wires crossed. But so far I haven't found any US vendors.


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## mcdanlj (Dec 3, 2018)

Yesterday, I confirmed that I really _do_ want a lathe this big. I had a rectangular part only 3" x 1" x 0.5" in which to bore a 0.8" hole only 0.4" from one end in the long dimension. I drilled and milled the hole out to 0.5" and then used a boring bar in the lathe the rest of the way out to 0.8" diameter.

The four-jaw chuck was able to hold my work, but if I had bought a nice "little" 11" swing lathe I think I would have had to clamp it onto a faceplate instead of chucking it, and I am guessing it would have been harder to center the hole. I indicated the milled hole to less than 1 thou with only about 2-3 minutes of work, which didn't feel horrible for my first time ever using a four-jaw. (Not challenging abom79 any time soon though!)

It wasn't actually critical that I indicate it quite that closely, but it was fun to take up the challenge. I suppose I should have pulled out the tenths indicator and kicked it up a notch! 

Anyway, I'm no longer second-guessing myself on whether I should have instead ordered a taiwanese 11x36 or so. I'm sure I'll be working with more awkward shapes in the future. If I get good enough to take advantage of (say...) a taiwanese 1440, I can save my pennies for that later.


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## mcdanlj (Dec 19, 2018)

Moved my new question about a KBPC-225D and DC motor to the correct section of the forum


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## mcdanlj (Nov 17, 2019)

I hated the piston-style QCTP that came with the G0709, so I bought a wedge-style QCTP from Precision Matthews, along with a pile of tool holders.

The QCTP bolt that came with the original didn't fit the new one, so I had to come up with a new solution.  I had a 1/2" x 2" piece of CRS stock, and milling slots along the top made it a perfect slide fit in the compound. Drilled it to 37/64" in the center, tapped it 5/8-18, and it was much better than the original.

But I hate wrenching the 1" nut on the top. Eventually I decided to make a wrench-optional nut. I had the drill and tap already, so why not?

I made a part 1.6" at the bottom, with a 20⁰ taper for the handle to keep it out of the way of the locking handle, and flats for a 7/8" wrench (same as I use to attach vise and dividing head to the mill next to it) at the top in case I get too enthusiastic tightening it down. Made six threaded sockets for the handle to make sure I can always find a convenient location; it wasn't much more work to do six than one anyway because I already had it in the dividing head for cutting the wrench flats. The dividing head was a convenient way to hold it at 20⁰ and turning the dividing head a few times is easy enough. The wrench flats on the nut are a bit imperfect because of a collet-not-tight incident, but the wrench worked and I don't feel like starting over.




Nut and handle are both CRS. The only stock I had big enough for the nut was 2.5" and I was too impatient to wait, so I spent a while making pretty colored chips taking it down to size. The handle is 7/8" stock turned down to 1/2" shaft, 10mm flats to match the drawbar on the PM-30, M10x1.5 thread on the end of the handle. I polished the handle down to 1200 grit before discovering that I really wanted some grip, so I knurled it, then used emory paper to knock down the sharp heads of the knurls until it was comfortable.

I know that making a ball turner and turning a ball is considered _de rigour_ for the handle, but I like this better.

I'm very satisfied and I think it will make the lathe more usable.

I know basically nothing about conventions for making prints, so the attached PDF won't look like anything you've ever seen before, but it probably conveys the idea well enough.

Here's a model visualization (without threads):


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## mcdanlj (Nov 24, 2019)

I have already made use of having multiple handle sockets in the nut to move the handle to a more convenient position for one particular operation, so I'm glad I did that. Also glad that I did them 60⁰ apart, as 90⁰ or 120⁰ would have been too much for convenience.


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## mcdanlj (Nov 25, 2019)

The shallow blind sockets seemed like a good idea at the time, but were a mistake. I didn't have enough thread engagement and damaged the threads. Also, the .2" wrench flats aren't deep enough. Finally, I didn't polish the bottom, making it more likely to turn the whole QCTP instead of just locking it down against the cross slide.

I have a slightly modified design, drilling the handle sockets all the way through the body, with deeper wrench flats.

If the new design is an improvement I'll share new prints. In the meantime if anyone else is thinking of making one, let me know and I'm happy to share new prints provisionally.


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## mcdanlj (Nov 29, 2019)

New QCTP top nut progress: It seems like it would be a good idea to use a needle thrust bearing under the nut to keep from turning the QCTP when tightening the nut:




I also modeled a handle. Here's a view of the assembly with the nut transparent to show bearings and bearing washers:




Here are the bearings (TC1423 or NTA-1423 equivalent) and washers I used in the model:

Bearing: https://www.mcmaster.com/5909K34
Washers: https://www.mcmaster.com/5909K47


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## mcdanlj (Dec 1, 2019)

McMaster won't sell me fewer than 5 needle bearings, so I went to ebay: https://www.ebay.com/itm/NTA1423-TH...SHERS-7-8-X-1-7-16-X-5-64-BAB170/123620961767

I managed to re-discover that when you drill out through an angled wall (relative to the axis of rotation of the bit) it's really easy for the bit to grab and break, and I ended up scrapping the part I was making as a result of the broken-off bit filling the hole and sticking into the center where it would damage the tap if I ran it through. I worked out a few more things I want to change in the design while I was working on it, so not a complete waste of time. And now that I have 1 7/8" stock, less of a waste of material, too.

I put the old 1" hex nut back on while working on the new nut, and set up the washer/bearing/washer stack under it, and it does have the effect I want of making it easier to set the QCTP angle.


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## mcdanlj (Dec 8, 2019)

I didn't scrap the part after all. I realized I could use a 1/8" grinding tip on the dremel to grind away the top of the drill bit, after which I was able to drift it through the rest of the way. I had mucked up the hole enough in the process that I drilled it through with the largest center drill smaller than my final size for tapping.

On to the next ops!


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## mcdanlj (Dec 8, 2019)

New nut looks a lot like the old nut, but works better, so the new drawings, such as they are, are attached.

Wrench flats at least 0.3" high are the minimum I would do.

The depth of the bearing seat is critical. The washers are .032" thick, and the lower washer must be captive but protruding. If you bore the bearing seat too deep, you can turn down the outer face slightly. I got lucky; I had forgotten to print out new prints in which, based on the models from McMaster, I had made the bearing seat 0.14" deep, which would have been too much. 0.125 might be OK; 0.13 works. Placing the washer stack properly is a pain. I had to poke the lower washer with a shim until it set into place.

If I were starting over from scratch, I would consider the thicker alternative washers and making the wrench flats 0.4" tall instead of 0.3", but these prints are how I actually made it and it's working.


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## mcdanlj (Dec 15, 2019)

It turns out that I made the threaded portion of the handle too long, and it mangled the thread on the rod before I figured out what was going wrong. I also didn't bore the thread relief deep enough, which makes it hard to start correctly. As long as I was tweaking things, I also made the flats 0.4" deep instead of 0.3" deep.

I have more work to do. ☹


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## mcdanlj (Dec 19, 2019)

I cleaned up the threads on the rod, bored out the thread relief 0.8"ø 0.6" deep, cut the handle threaded portion to .35", and it all works a charm now. I still have the 0.3" flats rather than 0.4" flats. I would make 0.4" flats if I were starting over, but good enough is good enough; on to other projects.


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