WARCO BH600G …taming the feed.

[Rik ShawParticipant @rikshaw]

[Rik ShawParticipant @rikshaw]

Latest mod to the lathe completed this afternoon. This was to fit a new 80 teeth gear to replace the 40 teeth gear on the Norton gearbox input shaft in order to reduce the feed rate which on this lathe is to fast for good surface finishes.

In this instance I bought a ready made gear online and turned of the excess meat to suit. The bore was opened up as well to fit the 18mm diameter gearbox shaft. I don’t know what they made the gear from but it wasn’t mild steel. It was tough stuff and the swarf peeled away blue even with flood coolant. Half a dozen burns later and the job was done. (I must remember not to wear T shirt and shorts when doing this sort of thing!)

The 5mm wide keyway was next. I was lucky enough to pick up a new 5mm MARLCO broach at a car boot earlier this year for 75p that the seller described as a “file”. I already acquired a decent sized arbour press around three years ago (and have never used since) so I was almost ready for the keyway but for one small thing – I didn’t have a broaching bush the right size.

A day later I finished making the bush and this afternoon I cut the keyway with the “file”.

The new gear keyed onto the gear box shaft snugly………

…………. and that would have been that but for yet another problem. The gear having a much larger diameter than the 40 teeth one it was to replace, fouled on the hinged gear cover closing mechanism preventing the door from shutting.

I fixed this by modifying the mechanism and re-sighting it on the cover. I was not keen on drilling the headstock casting to take a new stud so instead I made a little adjustable adaptor from an M8 nut and bolt which holds a 3/4” diameter countersunk neodymium magnet. The adaptor screws onto the end of the original closing mechanism.

It works so well that the door snaps shut when it is ½” from the casting.

With the greatly reduced feed speed I am easily able achieve a much better finish than before. A satisfyingly successful job and well worth the effort.

I am grateful to Howard Lewis of this forum who generously provided me with lots of useful info about this generic design of lathe and his recommendation for this mod in particular – thanks Howard.

Rik

[Michael GilliganParticipant @michaelgilligan61133]

Nice job, Rik

MichaelG.

[Michael GilliganParticipant @michaelgilligan61133]

Nice job, Rik

MichaelG.

[Jan RaapParticipant @janraap84676]

What a great idea!

I have the Warco 350 (basically the same thing just an earlier version).

Can you remember the gear size for this lathe (MOD/DP)?

Edited By Jan Raap on 09/01/2023 09:07:41

[John HaineParticipant @johnhaine32865]

They are probably mod (metric) gears. Take an even numbered one, measure across the outside of the teeth, use the formula OD = (n+2)*mod.

[LathejackParticipant @lathejack]

 

 

Nice job Rik, this might inspire me to finally get on and do the same job on my lathe.

It is many years since I fiddled with a Warco BH600, but I think the finest longitudinal feed rate is 0.0047" if I remember correctly, which is a little too course for a fine finish.

I have a Warco GH1330 and it has the same issue, but the problem is disguised somewhat because when new these lathes come supplied and fitted with an extra set of changewheels. With these fitted the finest longitudinal feedrate is 0.0026" and uses a 100 tooth gear on the gearbox input shaft, but threads cannot be cut with this set up.

When the changewheels are set up to cut a range of imperial threads the finest feedrate increases to over 0.0052" and this uses a 48 tooth gear on the gearbox input shaft. So despite having a full screwcutting gearbox it still requires fiddling about with messy changewheels in order to attain fine feeds or threads.

So for for many years I have been intending to fit a 96 tooth gear on the gearbox, this would allow some thread pitches and a feedrate of around 0.003". Or cut a new feed worm with an 8 TPI pitch and matching gear to replace the 4 TPI worm that sits behind the apron, so then the screwcutting  changewheels can stay in place, might get round to that job one day.

 

Edited By Lathejack on 09/01/2023 14:15:43

Edited By Lathejack on 09/01/2023 14:28:02

[LathejackParticipant @lathejack]

Posted by Jan Raap on 09/01/2023 09:07:02

I have the Warco 350 (basically the same thing just an earlier version).

It would be interesting to see some photos of your lathe. I remember that in the1980's, before their BH1127 then 1327 lathes, Warco offered a lathe similar to their much later Chinese made BH600.

The earlier lathe had the same looking castings and components as the first of their Chinese BH600 lathe, but the much earlier version was produced in Taiwan and built to a higher standard. It also had a lathe bed formed with three vee guidways, with two vee ways being used to guide the saddle.

I thought this was the model BH300 or 300B, with 300 referring to the swing, but I wonder if your Warco 350 is the same machine I am thinking of.

[Jan RaapParticipant @janraap84676]

I believe mine has been built in Taiwan. It has got three vee guideways and was built in 1980.
It looks to be an exact copy of the Lantaine lathe (probably the original manufacturer).

Taiwanese lathes

I went and took a few photos quickly.
The lighting is not great in that part of the garage.

[LathejackParticipant @lathejack]

Jan, thanks for the photos, yes, that is the Iathe I remember. A very good lathe, and the triple vee guidways are a very nice feature.

It is the same lathe that was also just branded as the Lantaine, and also branded as Lam as well as other names. A quality Taiwanese belt drive lathe, but the triple vee ways is what distinguishes it from similar versions.

 Would be interesting to know if it has a similar fine feedrate to Riks much later Chinese BH600, which is clearly descended from it.

Edited By Lathejack on 09/01/2023 23:04:41

[Jan RaapParticipant @janraap84676]

The Warco 350 was my first lathe, I also bought an Elliott Omnispeed lathe (much heavier) which is outside under cover.

As soon as the weather improves a bit I will start refurbishing/servicing the Elliott and then the Warco will have to go, unfortunately.

However, for a first lathe, the Warco is serving me well and I will be a little sad to see it go.

[not done it yetParticipant @notdoneityet]

Rik,

Good job, well done. I’ve cut gears I’ve needed, in recent times. An aluminium gear would likely have been more than adequate? Twenty quid gets a cutter, for life, is my take on it.🙂 But I’ve yet to cut an 80 tooth gear – 40 teeth take long enough!

I have always needed to make a guide, of suitable size, when broaching! My internal keyways get the ‘shaper’ treatment if possible.

Both your press and broach were good value – a definite ‘steal’ for the broach and the arbor press at a reasonable cost (presumably). It’s what I have done for a lot of my kit – good quality second hand is often just a good or better than new chinese stuff (of suspect quality).

One question: Was reducing the first driver, to half the tooth count, not an option? That would have been my first choice, if practicable.

[Howard LewisParticipant @howardlewis46836]

A long time ago, I made the same mod to my Engineers ToolRoom BL12 – 24 and had the same problem of the gear cover retainer being covered by the new 80T gear

From memory, it was 1.25 Mod, so should be 65.6 mm O D. (The original 40T would be 33.6 mm O D )

Unfortunately, it was impossible to remove the cover retaining handle without damaging it.

Fortunately, there was a suitable replacement available, so when located to engage the repositioned stud, it was locked into place with anaerobic.

This modification, with suitable arrangement of the 120 / 127T Idler gives a finest feed of 0.0025" (0.0635 mm ) / rev, which improves surface finish

The mod did cause me problems, when screwcutting, and I forgot to select the gearbox combination for a pitch supposedly twice as coarse as that required.

Experience is what allows you to recognise the mistake, the next time that you make!

Howard

[Jan RaapParticipant @janraap84676]

Your measurements do not make sense to me.

I measured my 40T gear's OD at 52.4mm.

I presume it is 1.25 mod gear which should measure at 52.5mm OD.

A 80T 1.25 mod gear's OD should then be 102.5mm.

[Mick DobsonParticipant @mickdobson]

I had a similar problem with the too-fast feed rate on my Chester Coventry 0632A lathe, which is basically (I think) identical to Warco GH1330. My lathe is from 1997 when Chester machines were painted green, the same as Warco. Now of course they are painted grey.

I managed to use gears from the existing set of change gears and arranged a compound gear drive such that the gear ratio was modified by a factor of 2.62 slower than the original set up. I had to make new studs for the gear sets as well as a slight modification to the gear quadrant bracket. The slot in the bracket was lengthened by 7mm in order to just accommodate the gear stud next to the spindle driver gear.

The pictures show the set up, plus a very rough sketch of the layout, which is often how things are made in my workshop! Note that the feed selector lever has to be positioned opposite to as originally marked to drive the saddle or cross slide the correct way.

This may also fit LatheJack's GH1330 lathe

[Howard LewisParticipant @howardlewis46836]

Sorry, mental aberration and divided when i should have multiplied.

At least my memory seems to have survived nearly 20 years regarding the Module.!

Howard

[Jan RaapParticipant @janraap84676]

Haha no problem!

I forgot what I ate last night

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