If they are unobtainable as spares and the PA is 20deg you can turn the old teeth off and buy new from HPC then bore to fit. 'Glue' with Loctite 603 or similar.

Is it a hybrid from some weird genetic experiment?. if so try channel 70 

Edited By Dave Halford on 11/03/2020 20:52:44

How about just removing the gears and doing a stepper motor and encoder conversion as per this thread

Electronic leadscrew

STEVE

If Warco cannot provide spare gears, it maybe that some other importer such as Axminster can.

The gears are likely to be Metric, so will be 1, 1.25 or 1.5 Mod, possibly.

If you can measure the gears, (OD and Tooth count, the Module can be calculated.

Depending on how the gears are driven, keyed or splined to the shaft, it might even be possible to replace the damaged gears with ones from another make / model. But they may need the bore to be modified to fit

Howard

With no syncromesh the changing of gears will always need a bit of help by rotating the huck the chuck.

So first thing to do is make sure it is in either forwards or reverse, no point in rocking the chuck if you are in neutral as it won't move the other gears. Move the left lever to the desired position while rotating chuck by hand.

Next will be selecting A, B or C while slowly rotating the chuck by hand

Finally select lead screw or feed shaft again while moving chuck noting that if in position C you won't get as much movement of the gear train as when in B. again while moving the chuck

If you opt to change on the fly with the lathe running don't do it with any feeds engaged and pause at the neutral, between C&B or between A&B before moving the lever further to the desired position

Wow, permitted to change gears on the fly! That surprises me.

I would not be changing any spur geared box while rotating at any speed. A really poor design to have the gear positions dictated by the control knob, unless it only fits in one position. It would seem that either the knob has moved (or been moved) or the gears have broken while changing on the fly.

They may even have never been in proper engagement from new? A truly cheap design?

The position of the knob appears likely able to be set ‘accurately’ by centring from either side of a neutral position? But a very basic positioning device for the sliding gear cluster. Once again, a design built down to a price?

That is my personal view of this problem. Others may disagree and be content with the cheap design.

Yes, a bit wider with the 3 extra gears on the right to select either the lead screw or feed shaft and of course an extra knob and selector arm.

John

If the WM280/290 gearbox is similar to the WM250 the biggest problem with an oil change is getting the oil out as the drain plug is half way up the left hand side behind the change gears. So to empty it completely you either need a sucker or take the front off which is messy. I fitted an extra drain plug on mine behind the aluminium front plate *** LINK *** which is much closer to the bottom of the box.

John

Barry,

Started reading this post whilst making breakfast this morning, The inner engineer woke up then the diagnostician started yammering multiple scenarios in my ear, so I was totally distracted. In the meantime I had cut some bread and buttered it. Forgot the toasting part completely!

Is there a chance of posting a picture of the damages gears, it would help the model engineering "hive" mind to assist you. Your comment about poor meshing suggests (in my mind) partial engagement along the length of the gear teeth perhaps?

With the cover removed, do the levers move freely and do the detents operate positively. As mentioned by Dave Halford, do the selector forks swivel freely and the floating gears slide freely on the shafts? As you will be stripping the gearbox to replace gears, it is a good time to check that the shafts and bearings are okay.

Are there any signs of excessive wear on the operating faces of the selector forks, particularly if there is damage to the front of the gear.

Yes it is a nuisance that you cant see what is happening with the cover in place, but you could measure the distance from the edge of the cover to selector fork faces in each of the lever positions, then move the gears manually by the same measurement from a suitable datum.. That may help to identify if there is a problem with the geometry/setup of the selector levers and detent positions, a problem found by quite a few owners of bench top mills with the Hi/Lo gear head down to poorly aligned selectors at manufacture.

The comments about crash boxes in posts above reminds me of a few choice phrases spoken by the chap who guided me though the process of driving older generation vehicles, ranging on order of kindness from:

"Its only a crash gearbox if you get it wrong"

"There's one in there somewhere"

"Alright, grind the b*****s down 'till they fit"

"Arrgh! &@!!^ #@££%&!, you **"%@@"

If coronavirus measures cause us to go into full self isolation, can't imaging anything worse than having your favourite toys out of action. Hope you get it sorted out quickly.

Edited to remove the easily spotted blooper, no guarantees that none remain

Edited By Mike Woods 1 on 15/03/2020 12:52:33

Without seeing the damaged gears, two thoughts

1 ) Trying , frequently, to change ratios while in motion; and crunching every time.

You can double declutch where you can closely control the speed of the prime mover. But lathes do not normally fall into that category!

On a vintage bus or truck, yes, but no on a machine tool.

2 ) Incorrectly adjusted selectors, giving less than full face contact for the teeth.

probably difficult to rest with the selector panel in place.

CUE making up jigs to align the selectors when the gears are fully in mesh.

Do the gears mesh fully in all selector positions? If they don't, that could be a basic design flaw.

Keep us posted on progress!

Howard

Interesting that the damage seems to be on one half of the gear as first photo looks reasonably OK but second is a mess. Or did it come to a grinding halt when a tooth broke off and got in the works?

Looks a good call from the Manual picture below.

I know that Barrys lath went back to Warco when it was new as the selectors were stiff.

Wonder if it was broken circlip in it?

Steve