My new lathe a Warco 918

Hi Niels

Spec sheets below for the motor/box I have used its a MFA975D1041 ratio 140 to 1 listed as 67rpm @ 12 volts though there is a +/- 12.5% on speed, mine is nearer 85rpm on 12 volt. You can see the gearbox torque figures on the sheet, cost of motor around £30 and Farnell stock them, others sell them but watch pricing. There are other makes of course Maxon are excellent but a bit pricey, Mclennan and Micromotors are also good. Just be careful of the cheap motors on Ebay, some are good but some are not.

I have some experience of the MFA motors as I used them in my Electric RC aircraft days. The 975D comes in 5 ratios and I went with middle ground thinking the others either side either too fast or too slow. Quality is very good and they are very robust having a heavy duty feel about them considering their size. The box is a planetary type which is good on efficiency and well engineered.

Nothing clever on my part re the motor/box, a mix of trial and error and a bit of gut feeling for what would be about right which fortunately worked out. The range of speeds and the torque seems about right for most turning/parting or at least for how I will be using it. Having a driven feed for parting was probably the main reason I decided to do the mod.

Certainly worth doing if you fancy adding a drive to yours, a short video below of parting which you asked for it works well.

Ron

Lovely parting off without drama and tears.

What was diameter of subject?trying to calculate feed/rate that is on the low side for my taste.

918 lathes are wildly underated here and go between 250-500 £.Must have one.

The work is 1.75" steel unknown but it cuts nice. When it comes to parting off I throw feed rates out of the window I just aim for a cut with no issues or problems if it takes a bit longer I don't worry. I just think of the material the diameter and guestimate a spindle speed and feed, if the machine sounds happy so am I. I do tweak the speed and feed if I think I can get away with it or if it needs it but otherwise I leave well alone.

That's just me though I'm the same with turning and milling I go by the feel and sound of the machine regardless of what the books and charts say.

Can anyone with a 5 inch 3 jaw tell me its capacity across the inside Jaws, I appreciate it may differ across the makes but would have thought they would be similar.

I have done a bit of a search in a couple of places and it's coming up with approx 40mm which I find a bit odd as my 4 inch 3 jaw can take 40mm, I was expecting more like 55mm.

A picture of where and what 40mm will open a torrent of wise guy comments.

Seems most 5 inch 3 Jaws are listed at around 40mm but the practical dimension is listed as 50mm well that's what I found on a couple of sites.

There is a reason for outside jaws, large diameter parts up to the diameter of the chuck. The issue with large diameters and inside jaws is how much jaw stick out beyond the chuck diameter is acceptable. If you are buying a new chuck I would suggest getting one with inside jaws, outside jaws and two part soft jaws.

Martin C

Ps There have been a couple of threads regarding jaws with teeth snapped off. This is probably due to people using inside jaws beyond their design capacity. 

Edited By Martin Connelly on 02/08/2020 09:33:57

Thanks Martin yes I am thinking of getting a 5 inch chuck it comes with inside and outside and soft jaws are available. I wouldn't use the inside jaws with them relying on the last tooth far too dangerous, I was just curious as to the capacity of the inside jaws on the 5 inch (used correctly) hence my original question.

Going with the 5 inch from ARC £50 and a 1.5" x 8 tpi backing plate, price is very good and I am hoping it will be as good as the two chucks I had from them for the mini lathe, they were spot on making them great value.

Just thought it best to check with you guys so I dont make an error, will a carbide insert (ferrous type) manage to cut the jaws of a 3 jaw chuck ok..? I know the jaws are hardened but wondered how much.

Edited By Ron Laden on 31/01/2021 13:47:34

Just thought it best to check with you guys so I dont make an error, will a carbide insert (ferrous type) manage to cut the jaws of a 3 jaw chuck ok..? I know the jaws are hardened but wondered how much.

Just thought it best to check with you guys so I dont make an error, will a carbide insert (ferrous type) manage to cut the jaws of a 3 jaw chuck ok..? I know the jaws are hardened but wondered how much.

See if the jaw can be scratched by a file first. Whilst Carbide is harder than the hardest steel, a very hard steel will give carbide a run for it's money. If the jaws scratch, they're relatively soft and carbide has a good chance. If the file bounces off, then carbide will struggle more. Carbide will win the fight but it could be painful.

Grinding is better for hard materials.

Re jaws, the limit is set by the number of teeth engaged in the scroll, and how brave you are!

The 3-jaw on my HV5 will just hold 65mm diameter but 3 of the teeth are completely outside the chuck:

Looking inside the slot, it can be seen only one tooth is engaged with the scroll, and at full extension it's marginal: any further and the jaw disengages.

I would trust this chuck up to about 50mm diameter, and might risk holding a light job up to about 60mm. Depends on the design, other chucks might be a little better or a little worse. Since a big job levered itself out of a chuck with a metal bending bang I've been less brave! The further the jaws come out, the more nervous I get, but it's a judgement call.

Dave

Edited By SillyOldDuffer on 31/01/2021 14:25:28

Great work Dave. Super find and lots of clever stuff since.

Did I see that moving the switch to the left means it goes away from you, rather than moving the switch away from you means the machine goes away from you?

I've just acquired a warco 918 looking in excellent condition. looks hardly used but really disappointed with it. The idea of having to take tension off belt before starting to avoid breaking bel, seemed very odd and maybe design fault? Any way I played their silly game to the letter but when working with it the belt flies off regularly no matter how carefully I do it. Also the 5mm vee belt regularly twists itself. can't seem to get a good finish on mild steel as slight chatter marks appear. People on here seem to have good things to say about them. I'm not new to turning being 77 and in the game most of my working life. Just don't like the lathe. Any input gratefully received

wally

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The cynic in me would note that Warco appears to have a reputation for providing ‘no quibble’ replacement when faults are reported … people take comfort from that, and say good things about them.

MichaelG.

To save people replying in two separate places can I direct further replies to Wally's other thread.