My Chinese Mini-Lathe Experiences

[90GTVert]

The belts came in from McMaster-Carr.




Neither the 5mm or 0.200" matches the stock belt.






The 5mm is the closest, but doesn't mesh with the gears very far.




The T5-420-10 fits. It's shorter than stock, but there's enough adjustment for it to work. Even though it's not right, I used it to make a bushing today anyway. No issues even with drilling and parting. I thought it may slip. I should still find something better, but this could work if it had to.

[FrankenMech]

With a lathe at your disposal you could make new pulleys...

McMaster and others have standard parts that can be bored to size. Keyways may have to be taken to a machine shop unless someone here knows how to produce them. I have always used a keyway broach. If the pulley bores are a standard size they may be available for purchase. Bushings and sleeves can be made also.

Check these links for replacement parts also:
littlemachineshop.com/
www.mini-lathe.com/

You may also want to Google 3/16" timing belts.
3/16" = 4.762mm.
That lathe is a design that has been in production many years and some parts may be 'Engrish'.

Lay the belt out and measure 10 pitches and divide by 10.

[lordverminaard]

I have been watching this thread with great interest. I have always thought I would like to get one of those little mini lathes and figure out how to do stuff with it, but it seems so daunting. With you sharing your experiences and the experienced guys chipping in their knowledge, it has answered a lot of questions already. Thanks for sharing and especially, a big thanks to the generous folks that made this happen and started Brent on his journey, lol.

Brendan

[90GTVert]

If you've got the cash to spare and like to tinker, I think this thing could keep you very busy for a very long time. I'm just taking it as it comes at this point. If I feel like I have to learn this or that, then I won't like messing with it. I prob won't get anywhere fast that way, but I still know more now than I did last week and so on. Once you turn a couple of things out, even if they aren't the most useful, it does make you want to do more.

[FrankenMech]

I always found that 'needing' to do something was great for focusing attention... That is my ADD talking.

[90GTVert]

I made a tool like oxtoolco showed HERE to do turning OD and facing without having to swap around bits/positions.





I made this yesterday for the TaoTao. I think it's mostly pointless, but I had a piece of aluminum around that was about the right size so I did it. The goal is to extend the tube a little to try and hide it from wind. Grooves line up with ribs in the tube. If nothing else, it's decorative.

[90GTVert]

I picked up a 3/8" insert style boring bar.






Also ordered a 10 pack of inserts for that and for the cutter set that I have. Both from China. Making a note here so I can find it :

Boring bar inserts : CCMT21.51
Tool bit inserts : TCMT21.51

[FrankenMech]

You will love inserts.

[FrankenMech]

When turning make sure your tool point has the least amount of overhang as possible. This will greatly reduce tool chatter.

Have you sorted the belt pitch situation?

I may have found a solution for my lathe motor:
amazon.com/gp/product/B072B83T22


BTW, turn those little brass thumb screw adjusters on your tool holders over so the knurl is on the top. It makes it easier to get your pinkies on them for adjustment.

[90GTVert]

Aug 16, 2017 20:26:00 GMT -5 FrankenMech said:

Have you sorted the belt pitch situation?

No. I haven't taken it apart anymore. It still has the belt that shouldn't work on it, and it's still working like the stock belt. It did slip at times when boring with the tail stock, but so did the stock belt. I assume it's not wearing well, but haven't looked.

[FrankenMech]

When torque is required the belt can 'slip' if it is the wrong pitch, not tight enough, or the pulley shafts deflect. Your original setup with the broken motor mount would cause the pulleys to deflect.

[niz76]

 Wow I just read through this whole thread and it's awesome!
Great job fellas on delivering this giraffe and a whole bunch of goodies too!   Dang Brent some of the stuff you're already making looks awesome. Those knurled handles are sweet. What a great idea this whole lathe thing!

[90GTVert]

I used the live center for the first time. I was working with 1" steel and it wouldn't fit through the chuck. It wobbled without a center. I guess I would need a steady rest to be able to face it off right, because it couldn't take even a light cut well. After it was machined down, I could have fit it deeper in the chuck, but I really didn't need perfect ends on this. The center worked well though. I was expecting that it may get hot or warm, but no issues and it kept the work from wobbling. Just wanted to update since I never talked about it.

[FrankenMech]

Wobbling can lead to a flying object, very bad mojo. It is a good thing to use that center. You can also buy inverted-female live centers.

I see you have an insert in the tool holder.

[90GTVert]

I was working on the lathe and I started to hear some noise, then more noise and it didn't have much torque. I took the cover off to find the belt very loose.




I thought the motor must have came loose, but it was still very tight. I pulled the belt off without having to loosen the mounts and found that it also had chewed up teeth and was coming apart, so I guess it stretched.






I measured the stock belt, but I'm not real confident in the pitch. I tried to measure outside to outside and inside to inside, but I kept getting different numbers. They were all 4.5-5.0mm, but close doesn't seem to be good enough and an accurate measure there sounds easier than it is for me. Averages out to about the 3/16" pitch that FrankenMech mentioned. I was trying to get something done, so I put the stock belt back on rather than do 20 more measurements trying to figure it out. I did wrap the fishing line around the outside fo the belt this time, as I think it should be done.