Mini lathe WM180 AMA180 Weiss

[Mike Carter]

Hi All, I was just wondering if anyone here has one of these Chinese 7x12 minilathes as above. I got one second hand and it has so far far exceded my competence so it's been a great learning device. However when I got it, although it came with many of the expected bits, lots of those turned to be for a different machine. My current problem is change gears, mine are designed for a 4 splined shaft whereas I have 12 mm shafts with a single 3mm key. Getting a set of gears to fit this machine is proving very difficult. I think the machine has been superceded and change gears weren't usually sold separately from the machine anyway. I have tracked down a set of generic minilathe gears in the States, but it's not possible to tell if they are an exact substitute unless I can compare gear diameters and thus tooth size. So if anyone has such a machine could you let me know the diameter of say the 80T and 45T gears please?
Many thanks all
Mike

PS if anyone can suggest a machine that the 4-spline gears might fit I'd appreciate the info.

 

[Pete.]

My first thought is do the gears slide on the shafts and engage the single key or are the gear centres a loose fit on the shaft? If they slide on the shaft nice a snug I would just use the single key. The machine won't have the power to cause it any stress.

 

[Kram]

These are plastic gears if your splined ones are steel, better to modify them to fit.

http://www.arceurotrade.co.uk/Catal...er-C3-Mini-Lathe-Spares/Super-C3-Change-Gears

http://www.amadeal.co.uk/acatalog/Change-Gears-Set--Metric--AMA_SP_CGS_M_RB.html
http://www.amadeal.co.uk/acatalog/Gears.html

Warco WM240/250 gears are steel, 16mm shaft and 4mm wide x1.5mm deep keyway (last week I turned a handwheel for leadscrew for finer feed when milling).

Bore out your splined gears, press fit a new centre, bore and mill a keyway. This will also ensure they are perfectly concentric - some of mine are slightly out.. usable but annoying when setting clearance.

http://www.arceurotrade.co.uk/Catal...per-C3-Mini-Lathe-Upgrades/C3-Metal-Gear-Sets

 

[Pete.]

That's an option (except that you can't mill an internal keyway) but if the ID of the spline in the gears is larger than the hole in the keyed gears it would be better to make a few splined adapters since they can be made in one and parted off. That way you could swap gears on the adapters instead of modifying every single gear.

 

[Mike Carter]

Thanks all for your help. The gears I have are different tooth numbers from the ones usually supplied and have only two in common. I will see if I can calculate any threading reductions with these numbers. Modifying the gears is (at present) beyond me, I don't have and have never used a mill, but given the tooth differences above I suspect it wouldn't be worth it anyway. I had tried Amadeal first (they originally supplied my lathe) but they don't have the gears for it despite those in their catalogue. I think they are mainly pushing the CJ18 and it's gears I'm told, aren't compatible. I had also seen the C3 gears and had the same questions about compatibility really. I wanted to compare gear diameters because I suspected that there must be more to compatibility than shaft and key size? Maybe this is wrong?

 

[Kram]

They are all made in the same factory by www.weiss.com.cn/products_detail/&productId=210.html but yours might be an older model. Id expect they will be compatible and will have the same teeth (diametrical pitch/module). The plastic gears are quite cheap get one to test against your spindle gear?

Keyways can be broached, quite easy to do on a lathe, you'd only need a 3mm square ended tool.

That's an option (except that you can't mill an internal keyway) but if the ID of the spline in the gears is larger than the hole in the keyed gears it would be better to make a few splined adapters since they can be made in one and parted off. That way you could swap gears on the adapters instead of modifying every single gear.

Not perfect as either the corners will be slightly rounded or need finishing off with a file. It wont matter if its a tight fit and no play.

 

[Mike Carter]

Yes I have mailed Weiss as well... twice! So far I haven't had a reply.

 

[Pete.]

Is your lathe imperial or metric? What pitch is the leadscrew and what toothcounts do you normally have?

 

[Mike Carter]

Hi again, I have a metric lathe but that's the only one of your questions I can actually answer. However I have now ordered a metal set of gears for the sieg c3. These are the same dimensions as regards shaft, key and thickness, and come with a versatile assortment of tooth sizes. Both The EU and US distributors think these should be fine. Since there is a UK distributor they are cheaper as there are no additional import levies. I will let the forum know how they work out.
Thanks all
Mike

 

[Pete.]

If you have a dial gauge or a digital caliper you can check the leadscrew size by holding the gauge on the bed against the carriage and turning the leadscrew exactly one turn. How far the carriage moves is the pitch of the screw. Chances are it's a 2mm pitch screw but it might be 1.5.

 

[Pete.]

Any news Mike? Did you find out your leadscrew pitch?

 

[Mike Carter]

Hi Pete- sorry for the delay Ive been away. Just tested the lead screw and its deffo a 2mm. I got the gears from the C3 and the good news is that they fit a treat... bad news is that I seem to need loads more tooth sizes from the manual. I confess myself pretty much baffled by the whole thing now.

 

[Mike Carter]

Tracked down a set of wm180 gears in Holland.... Bit pricey but at least no import duties. I have ordered these from Rogi trading Holland bv. Luckily Arceuro accepted a return on the Sieg gears. Have to say was v impressed with their customer service.

 

[Wedg1e]

That's an option (except that you can't mill an internal keyway)

I did once butcher a keyway into a motor pulley by drilling down the line of the keyway and then taking it out to square with files whilst repeatedly trying for fit on the shaft... not the most precise bit of engineering I ever did but it got the job done.