# My G4000



## Analias (Mar 10, 2013)

I know it's not one of the old iron classics, but its a start for me.  I found a G4000 (dated 07/98) that was obviously taken care of by the last two owners.  The only defect I have found is the far right tab for securing the back splash is broken.  It's all stock, with the stock tools.  The only difference from stock is the 6" four jaw that was included to replace the original 4" four jaw.  It also came with the cabinet stand, which I'm not using.  I need to secure it to the bench, I'm a tad reluctant to put two half inch bolt holes through the surface.  I suppose I have to, but the bench surface is pristine at the moment.

I decided to purchase a manual 9x20 instead of converting my existing 9x20 (which isn't complete) to CNC after reading about the problems that Steve is having with Mach3 on his.  Also, to complete the job I needed about $600 more than I had and that was just for the CNC conversion, not including tooling.  I'd like to have a lathe to use sooner than that.  I also wanted to learn how to work a manual lathe.

I've already placed an order with Little Machine Shop for a AXA QCTP, an A2Z four bolt compound hold down, and a set of 1/2 HSS indexable turning tools.  I'm going with indexable tooling to start with, but will eventually get a grinder and *try* to learn the art of tool grinding later.

I'd like to go through and check the alignment on the head and tail stock, and the run out on the spindle.  Can anyone point me to a good tutorial on how to align a lathe, or would one of our elder craftsmen be willing to make one for us newbies (hint hint - nudge nudge - wink wink)?

For the safety conscious, rest a sure I will get rid of all the junk above the lathe before I start using it.  Last think I need is something falling into it when in use - ouch! uch:


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## darkzero (Mar 10, 2013)

Nice score, it looks brand new!


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## Rbeckett (Mar 11, 2013)

Pristine!!!!!  Looks like it was never used.  A quick oil change and away you go.  Have fun and make some neat stuff.

Bob


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## fastback (Mar 11, 2013)

Nice lathe, looks to be in great shape.


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## Analias (Mar 15, 2013)

My order from Little Machine Shop arrived.  It contains my AXA QCTP, four bolt compound camp plate, and 1/2" insert cutters.  I ran into problems when I tried using the conversion bolt that I purchased for the QCTP, it would only thread a third of a way down on the stock tool post.  Good thing I have a second 9x20 that is disassembled, oddly it came with two complete compound slides.  One of the compound slides has bolt that the adapter threaded all the way down on.  It was also in better condition than the original compound slide and no play in the lead screw.

Once I got the new clamp plate and AXA QCTP installed, I discovered that to tool point was 3 or 4 mm above the center of work when the tool holder was in the bottom most position.  It looks like I'll have to throw the cross slide up on mill and take down the boss on the compound slide to allow the QCTP to drop lower.  I figure I'll take 8 mm off to give me some extra room for future tooling.  Good thing I have three cross slides in case I muck it up.

I'll have to add some pictures for before and after shots.

I discovered in another thread that there is a permanent thread about calibrating and aligning your lathe:

http://www.hobby-machinist.com/showthread.php/13710-Method-for-Aligning-the-Tailstock-with-Headstock


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## gdu (Mar 15, 2013)

Congrats on the new lathe.

Check out tubalcain's videos on youtube.

Mikail


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## Analias (Mar 15, 2013)

I disassembled the compound slide with the hope that the original tool post bolt would come out.  Grizzly's parts breakout suggests that it should come apart.

It looks like it was press fit with a pin to keep it from rotating.  Any suggestions on how to remove the post?  Should I try drilling the pin out or use a press from the other direction?  I'm afraid of damaging the bolt or the threads.


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## Analias (Mar 16, 2013)

Eureka!  A solution presented itself.  I was thinking it was small enough to fit in my 4" mill vice and then it hit me.  Why not use the mill vice as a mini press?  Sure enough, the compound slide fit in the vice.  I used a piece of scrap aluminum at the tool post bolt end to protect the bolt and the vice.  The bolt came out fairly easily.  

Now I have to work up the nerve to mill the boss off.  This cut would just happen to be the first real work I've done on my mill since purchasing it.  It's also the first time I have used a face cutter on the mill.  I tend to be pretty bold when working with computers and doing software development.  I've done that for the last twenty years and know what I'm doing. I'm new to all of this and I'd rather not throw money out the window due to my ignorance when I've already spent it at my tools.


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## Rbeckett (Mar 16, 2013)

You'll be fine.  Just take your time and make sure verything is bolted down and properly secured and start off with a light cut or two to get the feel.  Then shoot for a decent depth of cut and a final pass or two to finish it off.  I think you will do just fineit wouldnt it be easier to mill off the bottom of the AXA?  That will be way cheaper if you do mucj it up.

Bob


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## jumps4 (Mar 16, 2013)

I just used 3/8 tools in my 9x20  my 1/2" would not fit
steve


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## Splat (Mar 16, 2013)

I'd see about returning the 1/2" kit and go with 3/8". You would then not have to monkey around with the compound or the QCTP. I know it'll cost to ship it back and forth but in the end you'd be better off.


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## Analias (Mar 16, 2013)

Well that went well.  I measured what I needed to take off the boss and created a quick g-code file using the New Fangled's Mill Wizard.  Everything ran fine and I removed .140" off the boss.  I was able to align the tool tip and the center line off the chuck easily.  

I had originally intended to take down the whole boss, but when the lock ping hole appeared during one of the passes, I got curious and double checked the thickness of the material between the top of the boss and the bottom of the hole where the tool post bolt is pressed in.  I realized if I took the whole boss down I wouldn't have much left for the tool post.  I decided to err on the side of caution and interrupted job when I had removed 0.140".  That was enough to allow the tool tip to align with the center line.

Here are the money shots:





Here's some pics I took during the work:


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## Analias (Mar 16, 2013)

Splat said:


> I'd see about returning the 1/2" kit and go with 3/8". You would then not have to monkey around with the compound or the QCTP. I know it'll cost to ship it back and forth but in the end you'd be better off.



I seriously considered doing just that.  I had originally bought the AXA tool post and the 1/2' tooling thinking I wanted the extra mass to increase rigidity.  Since I have three compound slides, one being completely spare, I decided to try modifying one of the compound slides.  If it hadn't worked, I always had the option of exchanging for 3/8" tools since I have not used 1/2" tools yet.

I'd like to think the lathe is "mine" now since I had to go through the trouble of modifying it.  I look forward to doing several other modifications, like adding a DC motor, tachometer, DROs, carriage and tail stock cam locks, etc.


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## darkzero (Mar 16, 2013)

I doubt you will regret going with 1/2" tools though. It's a good choice IMO cause if you choose to use indexables you'll find a bigger selection of tools available in 1/2" than there is for 3/8".


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## jumps4 (Mar 17, 2013)

that looks like it should work out well
steve


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## Analias (Mar 20, 2013)

I guess my latest updates have been lost due to the forum database being restored recently.  I was wondering why I had no feedback from folks who have been helpful in the past 

To make a long post short, I got around to mounting some stock on the lathe and doing some test cuts.  I was not happy with the results.  As you can see, they could use some improving.  I did notice quite a play along the axis of the spindle and a more than I like across the axis of the spindle.  I plan to remove the main gear and see if I can tighten things up before I resort to pulling the spindle and replacing the bearings.

My second attempt at cutting the 5/8 steel rod improved a bit when I went up a notch on the speed (~600 RPM) and did a bit heavier cut, but still nothing to be proud of.

When cutting the steel rod, the lathe was making a hard "wha-wha-wha-wha..." sound.  When I check the run out on the spindle using the three jaw chuck from the HF lathe, it's not too bad at .001 to .0017.  As I mentioned the spindle has a lot of play in it when you push-pull on it.  It might only need to be tightened up.

If anyone sees what I'm doing wrong I would appreciate being the apprentice to your journeyman.  Please enlighten me.

My first cut into a 1.5" Delrin blank.




Some continuing effort, using 5/8 steel rod picked up at Lowes (unknown grade or quality).


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## kd4gij (Mar 20, 2013)

You need to get the play out of the spindle. If you have a live center. Spot drill the rod and use the live center to put pressure and hold the rod. you will get a better finish. The dead center will work just put oil on it.


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## Analias (Mar 21, 2013)

I decided to pull the spindle. I had to use a bit of ingenuity to pull it since I don't have a fancy spindle extraction tool.  I had to use what I had on hand:  a foot long 1/2" carriage bolt, washers, 123 blocks, a long 3/4" I-beam parallel, and some extra 1/8" parallels (for shimming).  Out the spindle came.

The bearings look good, as do the races.  Hopefully, I just need to put everything back together again and it should work.  I've heard that the bearings for the 9x20 are pretty easy to find.  Since I have the head stock apart, should I order some and swap them out?  Again the originals look good and move freely within.

Before I do put it back together, I want to check the roundness of the spindle where the bearings make contact.  I've seen a procedure for that using v-blocks and a DTI, but they also used a precision surface.  I don't have one, is that going to be significant problem with the testing?  I can't afford the cost and the shipping on the size surface I really want.  It will have to wait a bit.

At first glance it looks like I may have a problem removing the chuck side bearing.  It did not want to come off.  Any suggestions on how to take it off gently?  I could do the spindle puller trick in reverse against the spindle and hopefully use a piece of PVC pipe that is close to the same diameter as the bearing washers.


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## Analias (Mar 25, 2013)

Ugh, lots of lessons learned during the spindle swap out.   I'm not even sure I want to detail my mistakes, but I got the spindle swapped out from the HF 9x20.  I then ran the lathe with just the three jaw chuck attached for 20 minutes to break in the bearings in.  My thermal tester showed that the spindle temperature rose only six degrees over the 20 minute run. The "wha...wha...wha..." sound while turning is gone, and the lathe same sounds much happier.  When I measured the play in the spindle my DTI showed less than half a thousand along the axis and only one thousand perpendicular to the spindle axis.  I get a nice one and half to two revolutions on the spindle when I give it a quick spin by hand, so the preload looks good.

I'm still getting a rough cut, but much better than before.  I expect it's either spindle speed or the cheap Lowes bar stock I'm using.  There seems to be little pits on both the facing and turning cuts.


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## 8ntsane (Mar 25, 2013)

A few things you might consider, If you only got a 6 degree rise in 20 min run time, that isn't much. You could most likely stand for a bit more bearing preload. Another question is what type of cutting tools are you using? If your using carbide insert type, try turning up the spindle speed, other wise use HSS, and make sure you tool is on cenre of coarse. You might want to go over the gib adjustment too, make sure everything is snugged up. The finish on your test cuts looks pretty rough, almost as your spindle speed is to low, and the feed is to fast. But, I would check all these things first.


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