taiwanese lathe spindle

[gina]

OK I measured it in imperial . Wasn't sure which bit of the non threaded part of the spindle you meant .

I measured both .

I also picked up a metric gauge and I am confident it is not metric. The whitworth is a perfect fit.

So Spro it looks like a 2" by 8 tpi...

my next question is ....is the thread form standard??? that is 55 deg?? am I safeish to purchase a mounting plate bored for 2" x 8tpi??

[spro]

Yes Gina. Since you are new here, you saw how our Mentor figured this out and others confirmed it. It's pretty neat and we are always interested in what projects people do.. but not Too much. I mean we all do what we can but some point can be a nuisance. So you get help and understand why it was and then go to other nuisances or not. The whole time we learn more.

[gina]

well now the joke is on me....

Cant get 2" spindle backing plates anywhere.... Groan

[spro]

Well you already groaned so can't tell you anything. Of course I can. What joke? It is a serious lathe and you can get anything for it. Not a bad machine at all. There are elements of it which are in larger lathes which would have broke your back moving. So it is the right size for where it sits and many would like to be in that position with the quick change gearbox and geared head.. Liken it to a great novel where you don't quite get it first. Or it's a puzzle which you can't solve immediately. If you could, it wouldn't have been great. Along these times allow you to become more familiar with an open transmission of power, concentrated on working the strongest average substance. The chuck or faceplate is a matter of course towards defeating metal and cutting it to your purposes. It Will happen.

[Harold_V]

A suggestion, one that will lead to a slightly improved measurement.
On such a large and coarse thread, the width of your caliper may fit in one of the threads. Even if it doesn't, you're better off leaning the caliper at an angle, so the jaws span more of the thread.

I'm not a fan of using calipers for any critical dimensions. It has been proven more than to my satisfaction that they are not capable of yielding precise results. In this case, no big deal, but don't rely on them for serious measurements. I'd include the diameter of the register of the spindle in that comment, especially if you find you have to machine your own backing plate. Measure the register with a micrometer, and use a telescoping gauge for the counterbore in the backing plate. If you trust your calipers, chances are not good that you'll achieve the proper fit. That's not because of you, nor is there much you can do to improve on the odds of a good fit, not so long as you use calipers.

Note that I suggested that you may have to make your own backing plate. An un-machined casting is a possible source. Don't throw in the towel just because you can't find a plate.

Harold

[gina]

many thanks for the encouragement. and for the helpful hints

[arthur.marks]

I've been headed toward saying it is a 1-7/8" x 8 since this thread began, but the measurements seem a little all over the place. I'm also not convinced that the spindle thread is a 55-deg form just because an 8tpi Whitworth gage settles in. The pitch gage photo leaves me feeling much as with the measurements -- ambiguous. Obviously a male 60-deg. form will fit comfortably within a female 55-degree gage of the same pitch. But do the angles match, that is the question. I'm not seeing the characteristic rounding of the crest/root as is indicative of a true Whitworth form when looking at the spindle nose.

FWIW:
http://www.tools4cheap.net/proddetail.php?prod=178back
http://www.tools4cheap.net/proddetail.p ... 178back8in

[spro]

Are we seeing the same thing and interpreting it differently? If 8 fits at the depth shown and the span shown can it not be 8 ? The difference in thread form would scew it somewhat if it wasn't but the gage didn't appear to be scewed. So if it's eight and doesn't appear to modified, then it's also normal dia. 1 7/8" is too small. I purchased a Taiwan lathe from around that era. 2 1/4" X8 . This isn't a fastener thread. Mating plates, including the original with Polish chuck mounted bear on the "pitch diameter". That establishes the lock to the spindle collar and the precise surface of the plate and therefor the chuck.
I went all over doing face plates and back plates once. I could do sharp Vee internal and it wouldn't fit I could trunciate to a point. Then I looked at what worked and what came with it. Probably some Dykem involved. That was like 20 years ago.

[GlennW]

I have a Taiwanese lathe with a 40mm X 8 tpi spindle, and I know of 60mm x 8 tpi spindles, so it seems quite possible that you have a 50mm x 8 tpi spindle.

[Bamban]

Sorry for resurrecting an old thread, but I just inherited a motorless and chuckless lathe similar to the one OP showed in the thread. Though mine is a different brand and color, but it looks like the lathes all came from the same Taiwanese factory.

I am in the process of installing a 1 HP 3P WEG motor and a TECO VFD, the motorless aspect of the tool will soon be over. As with the OP I could not find any back plate to fit the nose. The thread is either 2 x 8 or 50mm x 8. At this point I am looking for any chuck with this back plate configuration.

At the moment I do not have the means to machine a back plate, my other lathe is down for apron removal and possibly parts replacement

If any of you guys know where I can get a finished or semi finished back plate with either 2 x 8 or 50mm x 8 thread., please let me know. Or if you guys have a spare chuck you can afford to let go, please PM me.

Thank you.

[AlanKay]

Good morning all,

Yesterday I landed one of these in my workshop, not even powered on yet, but Im already liking it. It's a great improvement from the little Unimat Jeweller lathe.

I do however have a question or two I am hoping someone will be able to enlighten me on.

i notice in the pics, the chuck actually screwed off, I assume the face plate along with the chuck screws off. How do I go about removing it? If it can be, can I use collets ?

Now for the biggie, I am used to the old lathe that was made before gears were invented. Is there any possibility that anyone has a manual or similar or is in the Melbourne area that I can watch and get a few pointers on it's use and setup ?

I look forward to all replies.

Alan

[spro]

The back plate which attaches to the chuck has the threads. Some chucks are direct mount. You probably need to be sure it isn't one of the cam-lock or tapered nose ones. So if you are sure it has a threaded spindle and verify the back gears are iron, there is the conventional way. There is a pin or screw in the bull gear (largest gear) of the head spindle. This connects to the largest pulley. If the back gears ( 2 gear arrangement) are swung in and locked against the spindle gears, the spindle is essentially locked when that pin is engaged. If that is true, a mallet against the chuck key would loosen the chuck. Even with this simple thing, you must inspect that there isn't a hole with a pin or socket screw locking the spindle thread to the neck of the back plate.