Ever hear of a Turnmatic combi 218? Me neither, so I bought it.

[RaisedByWolves]

This turned up on FBMP and it was so cute I had to buy it. Its supposedly a Taiwanese copy of a Unimat 4, but I really couldn't find much information on either other than they were both made in Taiwan.

Cute lil thing only about 18" or .5M long, and I was surprised to see the gearcase cover and many other parts are steel rather than plastic. It has a nice, but unmarked Enco style chuck made from steel rather than the zamak ones you see now. Tailstock chuck is nice enough, nothing to write home about but it will do.











Put my hand on it for scale as I didnt have a banana.









This is the handwheel of my Prazi SD400 I just replaced on the tailstock. The hand wheel is only 2.5" or so.










Im not sure if the Unimat 4 had change gear threading or power feed, but this little guy does and it works great. Im missing the threading change gears and only have the feed gears. I believe it has 12 speeds, 6 from belts/sheeves and 6 more via a 2 speed motor. It has a powered lead screw that is turned on/off by a kinda wonky gear engagement method. The gear in front at bottom slides in and out to engage/disengage the drive, but its wobbly and a little difficult to disengage. Ill have to work on that.










Took a .5mm/.020 cut in 6061 without breaking a sweat. I will try some tool steel tomorrow but I need to cut it short enough to fit and didnt have tine tonight.









I'm thinking of making a replica hardinge style tool post for this as the factory one is kind of odd and looks to be made for 10mm tooling, which would be kinda comical on this little thing.

Anyone know anything about these or the Unimat 4?


.

 

[GeneT45]

You don't keep a banana taped to the wall?

GsT

 

[Aaron_W]

I assume you've had a look at Lathes UK? Not a lot on the Unimat 4, but I did see this comment

Despite the different brand labels the clones invariably carry the model numbers MJ-189 (motor under the lathe), MJ-189A or Combi-218 - the latter seeming to be the most sophisticated of the breed with the same bed, but taller bed feet and a modified headstock casting that can carry a drilling/milling unit powered from the spindle motor.

Neat little lathe though, I'd have probably found a spot for it too.

 

[RaisedByWolves]

You don't keep a banana taped to the wall?

GsT

I did, but I eated it.

I assume you've had a look at Lathes UK? Not a lot on the Unimat 4, but I did see this comment

Despite the different brand labels the clones invariably carry the model numbers MJ-189 (motor under the lathe), MJ-189A or Combi-218 - the latter seeming to be the most sophisticated of the breed with the same bed, but taller bed feet and a modified headstock casting that can carry a drilling/milling unit powered from the spindle motor.

Neat little lathe though, I'd have probably found a spot for it too.

Thanks, yeah that was just about all I could find other than some really bad Ipotato videos on YT. There's a FB group for these, but its not much to speak of.

Shame really as the more I look this over the more I like it. The manual has a delivery date and some notes dated around 2002 and it looks like the company took the Unimat 3/4 and gave it added features.

I would normally say they upgraded it, but while it does have big lathe features the 4 did not, the overall fit and finish is not as nice.

Got a little time to mess around with it today and tried to cut some 5/16" O-1 tool steel. It was not as happy taking a .020 cut in this as it was in aluminum, which is understandable, so I tried to see if I could change the feed rate. It cut it OK at .020, but the motor bogged down considerably.

I first went to see if I could transpose the change gears for a finer feed and noticed.....Tada! A threading chart inside the cover.







This didn't help me much as when I went to change the gears there was interference with the limited sizes I had received with the lathe. I did find that the gears supplied were very well made with hardened inserts to key them together, that was a surprise.







I also found one if these little keepers missing, I can make that easy though.








When putting the gears back together I had a thought, something that doesnt happen often for me. I remembered I had some Chinese lathe change gears and dug around to find those. The gears were the right pitch, so that was good.

This gave me some of the needed gears, but the center was 12mm whereas this lathes gears are 14mm. No big deal as I can make the keyed bushings so these will fit. I would guess there's half a set in here plus some sizes that this normally wouldn't have that may come in handy.






And in doing this and operating the lathe for the little that I have I found the cheap gear door screw lacking, so I made my first modification. I had been given a couple old gear door thumb screws with one of the SD400's I bought and dug those out. These are especially nice as their one piece solid steel.


Before, needed a wrench to open and closing which was a PITA.








And after. I only had to open up the threaded hole from 4mm to 5mm-.8 and I had my first upgrade.









With some really sharp tooling I was able to make a .020 cut, and while it came out OK, the machine was not happy. There's simply not enough torque with the factory gearing reduction to the spindle. The motor bogs from 500ish rpm down to somewhere around 200. It doesn't give up and the motor did not get hot, but its definitely pushing it. I didn't think to check for belt slip, but this lathe does have a nice feature over the Unimats, proper V belts.

It did hold the correct speed for the initial 3/16-1/4" of the cut, but it then dropped off. I may recut the motor pully to get some needed torque in the future considering this.










And of course you get video. Not sure if I mentioned the feed engagement is a bit funky and needs work. This is why I'm already in the cut when the video starts and stops, didn't want to risk a crash.

.