Warco WM290 or GH600

Hi there, I'm selling my Myford and looking to get a slightly larger lathe. I will be using it for thread cutting, turning metric threaded adaptor parts about 3-4" in diameter.

The threads on the parts will be ISO metric 0.75mm, 1.0mm and 1.25mm.

I want to be able to switch quickly between these threads without having to play with changewheels like on the Myford which takes too much time.

The reason is that the threads are on the inside and outside of the part and I wouldn't need to remove it from the chuck. It would be batch-work.

I will use a DRO to get the part to the correct dimensions quickly.

My question is, would the GH600 or WM290V be better for this purpose, and which would be quickest?

I would like the ability to reverse without having to keep the nuts engaged if possible, and without the chuck falling off like you would get with a Myford.

Any advice or comments, appreciated, thanks in advance.

The WM290V does not have a screw cutting gearbox the GH600 does, so a metric version of the GH600 is more suited to your needs, neither have a screwed on chuck so reversing the spindle is no problem.

Tony

Just checked my WM280 on the off-chance that it's simple 3-speed gear box accommodated those ratios. No such luck, it only does x2 related pitches like 0.5, 1.0 and 2 or 0.75, 1.5 and 3.0.

0.75, 1.0, and 1.25 require 3 different change-gear settings on the banjo - far from ideal even if the workflow can be arranged to cut pitches in batches.

Lots to be said in favour of the GH600, but its noticeably smaller than a WM280 (750W motor vs 1500W, and 160kg vs 210kg), and a WM290 is bigger again (1500W, 320kg). In general big lathes are 'better' than small ones because they're less limited in what they can physically turn. They tend to be more rigid, and have larger spindle holes too, all good apart from size, weight and cost!

One day I'm expecting a hobby lathe to appear with an Electronic Lead Screw, which be told to do any pitch by pressing buttons or turning a knob. Various DIY implementations are available, but I don't know of an affordable off the shelf machine. In the meantime the GH600 is a good option, if quick thread changing is the priority.

The reason I don't own a GH600 is the WM280 is the biggest machine that fits in my workshop and I lathe cut threads relatively rarely: most of my threading is in tap and die sizes. It's a compromise: when big diameter threads are needed having to mess about with change gears is a right pain, especially when a workflow requires more than the occasional swap. Then I pine for a gearbox...

Dave

Not sure where Dave gets his 280 and 290 as being much smaller than the GH. Swing is the same as the 280 though a little shorter on bed length which does not seem like a problem if you are making adaptors. I also think Warco have the weights wrong as other supplier shave the same basic machine as 240kg and 260kg for the longer bed version (50mm more than 280/290)

As for motor size I would say the GH will have more "power" at the spindle due to the motor having a better mechanical advantage through the gears particularly at lower speeds. The variable speed machines have to have a more powerful motor fitte dto compensate for the fact they loose most of their grunt as the knob gets wound down to slow speed. Which is another reason to go for the GH as those pitch and dia threads will need a bit of grunt when cutting at low speeds.

Edited By JasonB on 21/07/2023 12:06:08

Edited By JasonB on 21/07/2023 12:07:04

Having recently gone through a similar exercise, I am going for the GH600 over the 280V (the 290V is bigger than I want / need, more spendy & currently out of stock).

The spindle motor power discrepancy that Dave mentions isn't as clear-cut as he suggests, due to the GH600 being a fully geared headstock the 750W (minus transmission losses) is available in all speeds. On the variable speed machines the power falls off as the motor speed drops, so often the motor is "over specified" at the top end to have more useable power at lower speeds.

While both GH600 & 280V are currently the same price, the GH600 includes the stand where the stand for the 280V is £330 extra.

Not sure why Dave thinks the 280V is larger than the GH600 ? There doesn't seem to be much to choose between them WRT footprint, with the 280V being only slightly larger & both are not much bigger than my Super 7 on the Myford stand - important for me as the lathe has to fit it to the same space the Myford is vacating. I am also not sure that the weight quoted by Warco is correct, as other sellers of what appears to be the same machine (Bernado Profi 600G / Paulimot PM3700) quote 200 -220Kg - it will be interesting to see what turns up. The 280V does have a slightly wider bed casting, 100mm more capacity between centres + a separate feed shaft to the apron (the GH600 has a keyway in the leadscrew for power feeds)..

I prefer the spindle start arrangement on the GH600 (lever off the side of the apron - down for forwards, up for reverse) to having to reach over the headstock to the spindle controls, mainly because I am used to this arrangement on the industrial Harrisons I have used. This should make screwcutting by keeping the half nut engaged & reversing the spindle easier - need to check the permissible "starts per hour" on the motor, though.

Untimately this seems to be a situation where either would do the job, both have features that are desirable (but neither have all the features ! ) & it is down to individual preference to rate the pros & cons of each design. Both feature a spindle mounting arrangment that I don't particularly favour (I would prefer a short taper + key-hole plate design, but only Chester may have that on one model that has that & it other, less desireable, features that led me to rule it out) but, for me, the balance of features on the GH600 won out.

Nigel B.

Thanks guys this is really good info!

My Myford has a 3/4 Hp motor and it seems perfectly fine for aluminium too.

Some other questions would be

How did you lift and move it around? Engine crane OK?

Is it delivered on the stand or separates?

Where would the straps go on the lathe and should I even bother getting it with the stand, or are they too flimsy to bother with?

Anyone got the DRO version, and if so are there any problems with the DRO scales blocking anything?

I think the GH600 is probably the way to go. I even have loads of old motor oil I can use

On my 280 I took off what would come away easily, wound the carriage to the far end and then put a nylon strap around the bed making sure not to squash the feed screws then hired an engine crane to lift it onto the stand.

I found the stand OK but replaced the flat middle panel with some draws

Google is thy fountain for wisdom : numobams 210-e lathe

From Warco's website, assuming their numbers are correct!

• GH600 is 160kg, footprint 1260 x 580 x 600mm, with 750W from 40rpm to 2000rpm (with one belt).
• WM280 is 210kg, footprint 1350 x 620 x 508mm, with 1500W from 30rpm to 2500rpm (with two belts providing high and low speed ranges)
• WM290 is 320kg, footprint 1302 x 635 x 1270mm, with 1500W from 30rpm to 2500rpm (with two belts providing high and low speed ranges)

All three were strong candidates when I was looking to buy bigger after deciding my mini-lathe was too small. The WM280 won because it was the right size and the sort of work I do doesn't demand gearbox convenience. Steve's requirement does!

Gears versus VFD speed control are more subtle. The WM280 delivers full power to the spindle at cruise and high RPMs and at 2000rpm a WM280 really is twice as powerful than a GH600. Not all roses though! Although the 280 has two speed ranges it's done by changing belts, which is a pain, and of course running the motor at low RPM with a VFD results in significantly lower torque. In practice, low speed, low torque doesn't inconvenience me because I don't cut many large diameter coarse threads. Whilst the 280 can do them, there's no doubt a gear head lathe is better for that sort of work. Nonetheless, I've never stopped a job and wished the lathe had back-gear.

Their different speed/rpm/torque characteristics suggest to me that a GH600 will be happier with HSS whilst the 280 gets more out of carbide.  If that matters!

I wonder how noisy a GH600 is compared with a WM280? Gears make a fair old racket. Not that my WM280 can be described as quiet though: even with the banjo moved out of gear, the lathe's two loud continuous electric cooling fans overwhelm my workshop radio.

Dave

Re Steve's moving question, an engine crane is fine. Just remember their splay legs mean a largish turning circle that can be awkward in a tight space.

Edited By SillyOldDuffer on 21/07/2023 14:41:24

But who needs that sort of power when you would only be running small dia work at those speeds?Its as the work diameter goes up requiring the spindle speed to come down that really matters and as the OP is talking of 100mm or so dia work then if using carbide at 100m/min surface speed you would only be looking at 330rpm.

I'd happily run carbide on the GH600 and if it is batch production of that sort of size part then full form inserts would be the way to go and as you could run the lathe approx 3 times faster that is going to drastically reduce production time not even taking in the need for sharpening the HSS and faffing about chasing in the crest radii.

As for noise the GH motor will be running at full speed all the time so it's integral fan will cope unlike when the vari speed motor on the 280 is only ticking over it needs extra cooling fans that make a noise

Edited By JasonB on 21/07/2023 15:08:50

with 1500W from 30rpm to 2500rpm (with two belts providing high and low speed ranges)

No, it says it is fitted with a 1.5 KW motor and that the speed range is 30-2500 over 2 ranges. It doesn't say that 1.5 KW is available at the spindle throughout the available speed range - that would be impossible with a variable speed drive. If the motor is running at less than it's 50Hz speed, it will be less powerful than the 50Hz rating.

I wonder how noisy a GH600 is compared with a WM280?

The manual on Warco's website says 78 dB (A) at 1 metre. There are a couple of YT videos of these machines being run and, while it can be difficult to tell from a video, they don't sound too noisy. My belt drive Myford isn't silent !

Their different speed/rpm/torque characteristics suggest to me that a GH600 will be happier with HSS whilst the 280 gets more out of carbide. If that matters!

Why ?

From Warco's website, assuming their numbers are correct!

I think the Warco website weight is wrong - the manual for the machine downloaded from them says 225 kg net / 255 kg gross. A YT video review of what looks like the same machine with DRO (badged Bernado) says on the crate before unpacking 230 kg net / 270 kg gross. That video is here & also shows fairly heavy cuts being taken with insert tooling.

How did you lift and move it around? Engine crane OK?

I have an engine hoist that I hope to use to mount the machine on the stand.

Is it delivered on the stand or separates?

The machine appears to come crated as Jason B's, with the stand separate & requiring some assembly.

Where would the straps go on the lathe and should I even bother getting it with the stand, or are they too flimsy to bother with?

I'll let you know when I figure it out WRT to getting a safe lift. The stand is included with the GH600

I think the GH600 is probably the way to go. I even have loads of old motor oil I can use

Do you have an old motor to use it in ? ISO 46 hydraulic oil should be fine in the headstock without absorbing too much of the available power. ISO 32 & 46 hydraulic oils are used in many industrial lathe headstocks.

Nigel B.

The GH stand comprises two vertical cabinets that act as 'legs' with a steel back-panel between and 2 shelves. They are topped by a full size tray with folded sides and welded corners and the whole lot together forms an adequately stiff structure.

Mine arrived with the lathe, think they were on the same pallet, crated lathe on the bottom, stand components on top, whole lot wrapped in transport film.

I moved mine (twice) as outlined by Jason, put a couple of bits of 4x2 under / against the bed to keep the slings off the leadscrew, I slung mine under the bed against the headstock and simply used a small ratchet strap between the hook and the tailstock end to level the thing up.

A 2t engine crane will lift it at full boom extension no problem.

When I ordered mine I asked them to stick enough oil to do a complete 'first change' on the pallet, I can't remember how much it was, buit it certainly wasn't much in the grand scheme of things.. ..it's plain hydraulic oil as Nigel says.

There is a certain amount of noise from the gears - they're straight cut, after all, but it's not, like, awful.. ..I don't use the splashback on mine, might make a difference I guess..

The carbide dogma business - never had issues using competently-manufactured CC*T inserts either ground or standard, I use them for all plain turning facing and boring work, along with carbide inserts for threading - 'though I also use HSS and carbon steel at times - they all have different qualities & uses.

I think I said the same! My point is VFD powered motors don't lose torque at high RPM. At the middle and higher end of the speed range, they perform as well as anything else. In which case 1500W trumps 750W.

Picking up Jason's question about power and rpm, carbide works best at high-speed and high-power. Taking a deep fast cut with carbide on my WM280 removes metal spectacularly quickly. I rarely run it flat out though because doing so creates an unpleasant spray of glowing chips. Taking it gently is more fun and less likely to set fire to my woolly jumper! The main advantage of the big motor is providing reasonable torque at low VFD speed, partly compensating for not having gears!

Though I'm drunk with power, any motor between 500 and 1500W is adequate on a medium hobby lathe.

Dave

Wrong!

Take a VFD and an induction motor designed to run at 50Hz. At 50Hz the associated speed is called base speed, and rated power will be obtained with the rated voltage applied.

Above 50Hz the rated voltage is not enough to maintain costant phase currents, so the torque falls off. But the speed increases, and since power is torque time speed the power stays constant. Which is what I think SoD meant to say.

Andrew