My Workman (G0602), my way

fitterman1

What a view
H-M Supporter Gold Member
Joined
Jan 29, 2017
Messages
311
This is my experience with what in Australia is called a Workman 250 x 550 lathe. It is exactly the same as what is also known as a G0602 as supplied by Grizzly in the US and comes under other names in different parts of the world.
Gday viewers my name is fitterman1 and I live in Australia down the bottom just off the middle.
I'm a mechanical fitter by trade and I bought one of these lathes a couple of years ago to plonk in the shed to make things for myself and others.
Since I bought it I've spent all this time on and off ripping it to bits and going over those same bits to come up with a machine that has some form of precision and repeat-ability in its function as well as a much improved feel in the way it is manipulated.
This write-up is going to take ages to complete because I still have to work out how to upload pictures. I'm also going to go about it in a haphazard order because that's how it happened.
So the story starts 2 yrs ago when this fella I know was shutting down shop.
He is a boilermaker and bought the lathe to bevel the edges of tubing and small od pipework prior to welding a butt joint.
That's all he used it for, and in the 6mths he owned it he reckons it did about 12hrs of work.
Anyway I took it off his hands for a bargain basement price of AU$500, they retail at $1250 on flea-bay by a local. Not a bad price if I say so myself.
On the way home I popped into a local tool vendors shop and also bought an engine lifting crane. I had to get it off somehow and the missus wasn't going to bend over backwards to help that's for sure.
Got it off and into the shed and set it up on its stand.
And looked at it. It was so low it could only be suitable for a person a meter tall to use. Talk about ergonomics. I prefer my chuck to be at chest height so I'm not stooped over.
I left it there and went inside and started to devise a stand in my head over the next few days which I fabricated at work in my own time using scraps from left over jobs.
The stand was made from 3" square tube with 1/8" wall thickness and was 1250mm long x 400mm wide with a height of 900mm. On top of that I fitted two pads which corresponded to the two end bases of the lathe. these were welded to the structure and machined flat and level in relation to each other. I can't show actual construction photos as they're nonexistent but here's the headstock end.
Worked out how to add pix.

Headstock end frame.jpg

and the tailstock end. This frame I made parallel and square in every dimension to within one millimeter.
You can see the pad that the lathes weight sits on in the center of the top beam. Even though both pads were machined I scraped them flat as well. There is a 010" gasket between the pad and the stainless steel swarf tray I made. The top beam was designed to be pulled one way or another by the bolts in case there was twist in the bed. Thankfully this bed was free of twist so these bolts are under minimum tension.

Tailstock end frame.jpg

This is how the frame is attached to the floor. 16mm studs grouted in at all four corners with Hilti stud grout and enough sticking out so that the pads where the lathe will sit can be leveled. The corners of the frame were reinforced with pads of their own to stiffen up the tube and spread any load more efficiently. The concrete is 6" thick here so no drama with load bearing.
Frame plate and stud.jpg

to be continued
 
Last edited:
Welcome I am a newbie to using a lathe same as yours g0602 and just gathering things to start. I must say you guys have the most beautiful country I have seen. Back in 2004 I was able to spend a month down in Denmark and drive and camp all the way up the coast to Perth. I still have friends in Denmark. Two places I consider heaven now there and here in Alaska where I have spent most of my life. Aaron
 
Hi AirlineRefueler, they're both beautiful places aren't they? I live in Adelaide at the bottom of a massive desert. It's green here but 500kms north and further you need to be on your toes to survive - very little water around.
I hope you like your lathe I find mine is very accurate because I've spent quite a bit of time hacking it. Some of what I've done you won't have to but at the end of the day the more you get a feel for it the more you will want to improve it as you find its minor faults.
cheers Alby
 
The next change I made was getting rid of the factory swarf tray which was only 10mm deep and was undersized in comparison to the frame dimensions which made it look odd. So at the workshop I grabbed a sheet of 1.6mm stainless and cut folded and welded a new one which was 25mm deep. The edges were turned up at 45 degrees and tigged shut. This covered the same area of the frame and looked better than the old painted one.It also catches swarf that dribbles out the spindle I've since found out.

Swarf tray.jpg

Then the lathe was loaded on and bolted to the frame. The frame had been fitted with m12 studs drilled and tapped into the pads previously. The headstock stud was cranked to 40Nm and the tailstock one to about 5Nm to allow the tailstock end to slide when influenced by thermal expansion. We have large fluctuations in daytime temperature here so I thought this is the best way to control that. As long as its clamped down slightly no issues will arise.
A machinists level was placed on the ways and the frame was gently adjusted for level in both directions and then the base studs were locked up and level checked.
Next thing on the list was to check the spindle bearings, just by rotating the chuck by hand I could tell they didn't feel right, there was a gritty feel to them. So off came the chuck and then I noticed the thread didn't seem too flash either.
So out comes the clock (dial indicator) and I check the register which was spot on although by eye I could see the threadform was not concentric with the register. It seemed to be eccentric to about 1mm.
I gutted the headstock. Spindle out, wiring out, bearing shells out, everything off or out. The bearings I found had casting sand floating about, it was stuck to the spindle exterior where there was grease, on the housing interior, everywhere. It was not a clean housing. The spindle I took to work and remachined the same thread, going deeper until it was complete and concentric. Then I made a protective nut to suit out of scrap aluminium. It looks like this.

Spindle nut.jpg

Then I made a duplicate spindle thread, it looks like this out of bronze.

Spindle thread.jpg

The nut protects the spindle thread when I use a collet chuck. I use ER40 collets. The duplicate spindle thread is now my template for all backing plates to be made to in the future. Their fits are near perfect, only on the hottest days can you feel any backlash between the two. Instead of 1.750" x 8 tpi, my lathe spindle thread is now 1.694" x 8 tpi a difference of 028" on radius, that is a massive error from the factory.
The headstock housing was taken to an abrasive blaster and he was instructed to blast the daylights out of the interior only. Thereafter I took it home and gave it multiple coats of epoxy paint to seal the surface.
The bearing shell seats were cleaned and the grease galleries cleaned and flushed out, then I set about scraping the base that sits on the bed.

IMG_0529.JPG

I scraped the entire base flat even though the only contact points are two strips where you can see the bolt holes, good for practice. See the non contact point in the center area above, there is no stress relieving in china, its pour, fettle, machine. It relieves itself afterwards. Without having a flat base that is parallel to the spindle axis, when you tighten down your nuts they will twist the housing.

Headstock bluing.JPG

to be continued
 
Last edited:
Wow! It really sounds like you're doing a great job turning a sow's ear into a silk purse. All that sand in the headstock must have been quite a shock to find. Beautiful looking work on the threads. And I especially like your design for the top beam at the tailstock end. Absolutely ingenious!!! I'll have to keep this one in my bag of tricks.

Can't wait to read more of your story ... and welcome to the forum!
 
Hi hman, and thanks for the welcome, yes the sand was a worry but knowing there was cheap chinese brgs on the spindle didn't faze me, they ended up in the recycle bin and new FAG ones ordered. I've done a fair bit on the lathe in the last 2 yrs mostly in between jobs home and away, I'm just gonna catalogue it for everyone elses benefit. As a fitter I know what its like to walk upto a machinetool, check it over, lube it up, use it, clean it, walk away.
The machine should be set up and operable from the get go you know, the best manufacturers of top quality machinetools and your shop boss would expect you to maintain this ethic. I became a fitter to experience a lot more than standing in front of a machinetool for the rest of my life. I have a lot of respect for the guys that have done this, as an apprentice I was taught by a lot of old fellas and they have a lot of tricks up their sleeves. Collectively they've passed this stuff on to people like me and you. I like pulling things to bits and fixing them so it was natural for me to get a lathe and do the same as anyone else on these forums, help others and share methodology.
cheers Alby
 
Last edited:
When I pulled my spindle out of the headstock housing I used a bearing puller to pull a) the outboard brg first then b) the chuck end brg second. What I found was there was too much interference on the outboard brg because this one is meant to slide with friction to allow the correct adjustment of bearing clearance. I took my spindle to work and chucked it. Then I polished with wd40 and wet and dry until I could force the bearing on by hand. Notice I said "by force", I didn't want it loose but still a tight hand fit. I also measured the chuck end and found that a little too high in interference so I took a thou off that end also. Still needed to be pressed on by tools but a lot better and smoother sliding motion. I replaced the original chinee brgs with FAG units on order from Germany. These were assembled to the spindle using some oil as lube for when pressing, this prevents any pickup or galling from happening. They were packed about 2/3rds full of a teflon based hjgh temp bearing grease and assembled to my headstock after it had another thorough cleaning with contact cleaner. Everything was spotlessly clean upon assembly. At this stage my headstock was nipped but not aligned. My headstock anchors were studs which were replaced with better quality and loctited in place and tensioned using a nut and washer to pull them upwards while they set. This way there was metal to metal thread contact rather than a layer of loctite to crush. The original washers were thrown away and new ones fabricated which were 4mm thick and as big as possible to fit in their location. The idea here was to spread the clamping load as wide as possible across the base of the housing onto the beds so no motion would occur in future after initial setup.
Next was the spindle adjustment. I used a clock on the end of the spindle and gently pulled up the first locknut till I had no motion. Then i spun the spindle to work the grease around and line up the taper rollers so they sat. Then I locked up the spindle with a pin spanner and tightened the first lockring more so I could feel tension in the bearings and then backed off the lockring and reseated it by hand. This last action should have properly seated the shells and rollers in their resting spots. I then spun the spindle to see how it felt, there was slight friction so I left it at that. Next was to perform a temporary alignment to the ways using said clock and a collet chuck was attached with 8" of 1" diameter ground bar. I set the clock
at 3 o'clock on the back of the bar gave it some preload and zeroed it. I spun the spindle to check runout, it came to about 0.0003". I spun it around back to the zero point and traversed the bed with the saddle to the end of the bar. It read close to 080" so I continued by adjusting with the rear adjusting grubscrews and traversing back and forwards until I matched my zero point. Tension on my studs was only a few Nm and I was also using a rawhide hammer to knock it around. I left it like this for a few days cause we had some long days at work.

Update - Have since completed my "temporary" alignment to within 001" over 8" of bar. I still feel I can get better than this. I'm going to do it again once the drive train is properly settled and I've machined numerous items and stressed it out. I'm interested to see how it copes or performs with indexable tooling, I'll also check it again at some time in the distant future as a comparison to identify if anything is moving or if its happy to stay as it is. The tailstock has been completely left out of the equation because after I scraped the headstock I found by clocking the tailstock quill that it was 005" high. I completely forgot to measure this for any errors prior to starting. It could mean I've taken a hell of a lot of meat off the headstock (possible) or the tailstock was originally slightly high anyway (also possible).

tbc
 
Last edited:
I remember leaving the lathe in that state and decided to focus on power and control. I had gutted all my wiring and thrown it in the copper bin as I'd made a decision to go variable speed, so I chased down an electric treadmill that still functioned and for $5o was allowed to take it home. I pulled it to bits and kept the dc motor (2.75hp but more than likely 1.5hp), control panel and necessary cabling. At this point I started to educate myself on the finer points of variable speed dc motors and came to the conclusion that the existing controller for the motor was not going to be flexible enough for my needs. I wanted to be able to start at any speed I wanted and be able to vary it. I wanted to be able to run it in reverse as well as forward. I wanted it to stop within a second or two. I wanted an e-stop. These things I couldn't have with the existing controller so I hunted the net until I found the K**M 225D. What a champion piece of electronics. Absolutely perfectly matched for my little motor. AC in DC out, 0-180 volts, good for 3 horsepower, all sorts of adjustable parameters on the board, reasonably priced and all I had to do was get it from the US to me. I immediately ordered one and then went and picked the brains of every sparky I knew to knock out the best circuit to build. Then the ensuing shopping spree that inevitably follows occurred. Over the next few months I built a control panel that sat under the swarf tray inside the frame and incorporated an external 12vdc power supply for lighting and fans also. At the same time I nutted out a way of mounting the motor in the existing motors spot and fabricated the necessary bits and pieces. The original intermediate drive pulley was toothed for a timing belt, I took this to the workshop and machined off the teeth after truing and machined it for a J profile ribbed belt and sourced a new pulley for the dc motor and suitable belt. A ribbed belt is much much quieter than a toothed especially at higher speeds.

Control box - 1 fan blowing in from below onto heatsink, another fan blowing it out. Programmable auto fan control on front window.
Control panel exterior.jpg


Box wiring
Control panel wiring.jpg


K**M-225D heatsink from an old variable frequency drive - temp sensor buried inside it hasn't seen greater than 28 degrees C (82F) yet. Pretty lush eh? K type thermocouple buried in center of heatsink - you can see the wires coming out.
Control panel heatsink.jpg


J profile pulley
Intermediate pulley.jpg


Motor mounts and adjustment
Motor adjusters.jpg


Drive arrangement
Upper drive pulleys.jpg

New headstock fascias are split so acess to headstock or gearbox is easier. Stainless steel 1.2mm thick provides better support for switches.
Headstock fascia.jpg


Its been up and running for a while now, this is one quiet machine. Even at high speed its quiet, the loudest noises are the ticking of the seam on the v belt as it spins past and the motor fan. Notice I've left the original stepped pulleys. I decided to do this to take advantage of really low speeds and high torque when the vee belt is on the far left pulley and really high speeds and low torque when set in the vee closest to the headstock. I haven't had to shift it from the center vee yet as I find with the speed pot dialed right down I can screwcut at about 40rpm quite comfortably and dial it up to 5 for about 800rpm.
These numbers aren't measured or calculated, I'll update these as soon as I can.

tbc
 
Last edited:
I like what you have done with your lathe I knew when my missus last summer was going to get rid of a nice tread mill her sister gave her it might come in handy at some time she told me to take it to the dump but i have it tucked in a corner of the garage as it has a 2.5 hp dc motor inside that I figured I might be able to use in the future.
 
I say grab the motor and bearings out of the rollers, turf the rest and reclaim some space.
 
Back
Top