An interesting Job---

[Brian Rupnow]

I built so many models over this past winter that I reached a point of total burn-out on machining. However, my daily engineering work goes on, and I have a customer who has to turn the commutators on a certain electric motor that he sells and services, which doesn't easily come apart. The decision was made to buy a mini lathe and make some special fixtures for it to hold the outer housing of the motor and use a drive dog mounted in the lathe chuck to spin the armature. So--I went to BusyBee tools on Saturday, purchased a mini lathe, and today I have modeled it, along with the fixtures required to mount and turn the motor. I love this kind of interesting thing when it comes along!!!---Brian

 

[Herbiev]

Ingenious design. I love it.

 

[Brian Rupnow]

I find it quite surprising that this Mini-lathe doesn't seem to have a carriage lock on it. My larger 10 x 18 lathe from BusyBee has a carriage lock bolt that tightens into a piece of steel riding underneath the ways. When doing any serious parting off, I always lock the carriage in place. Either there is a carriage lock and I just haven't found it, or else these must be a pig of a thing to do any parting off with.

 

[Cogsy]

Apart from it's colour and brand sticker, it looks just like the one I bought when I started this hobby. If it is, they don't come with a carriage lock and it's one of the first mods I had to do.

Another mod that I intended to do but never got around to, is a cam lock on the tailstock. Some models already have this fitted but now that I've got used to using one I definitely couldn't go back to not having one. I'd suggest that if your customers' machine doesn't have a cam lock that you design him one of those as well.

 

[bazmak]

Now you have a mini lathe you will have to read up on the threads
Lots of mods to do and a carriage lock is one of them.I have just
bought the Sieg SC4 8x20 and i am currently working on a carriage lock
Must have on this model with power cross feed. Regards barry

 

[Brian Rupnow]

The mini lathe is not for me. I have a full sized lathe. The mini lathe is for my customer, and will be used only to resurface the commutator on his electric motors which he sells and services.

 

[Brian Rupnow]

So, here we are---All detailed complete with general arrangement, and sent out for bids.

 

[Brian Rupnow]

Hey Cogsy--How did you make the carriage lock? Do you have any pictures?

 

[bazmak]

Hi Brian ,i did the carriage lock the thread is diary of a 7 x 16 mini lathe
photo shows it dated 12-09-2014. Regards barry

 

[Brian Rupnow]

Thanks Baz--I will have a look at it.---Brian

 

[Cogsy]

Hey Cogsy--How did you make the carriage lock? Do you have any pictures?

Sorry, no pictures and it really was just something cobbled together. Basically just 2 rectangular plates with a bolt through them that sanwiched the back of the carriage to the bed. I had to remove it when not in use or it got in the way.

I'd have preferred to lock the front of the carriage and to make some sort of cam-lock arrangement but I didn't have the skills or equipment back then - I didn't even have a mill. If I did it again today I'm sure I could come up with something better, but I'm sure your design will be far better than anything I could come up with.

 

[bazmak]

Hi Cogsey,i did the lock to the tailstock side of the carriage and it did get in the nway and restrict the tailstock travel.I am currently looking at doing one for the SC4 and to the headstock side will post if it works but it may reduce the swing.

 

[Brian Rupnow]

i had a look on Bazmak's thread about "diary of a Mini Lathe. Near the end of he thread he has some excellent clear pictures of how he made his carriage lock. A superb job!!!--Brian

 

[Brian Rupnow]

Can you cut threads with one of these mini lathes? This one has a complete set of change gears supplied with it, but there is no thread dial indicator. In the manual, it talks about threading and refers to "handle "A" in picture below", but there is no picture.

 

[bazmak]

Yes you can cut threads with the change gears,but no dial indicator
Once you engage the leadscrew and take the first cut you have to keep it engaged.Withdraw tool reverse the feed direction and travel back,wind in the tool change the direction and cut again.I success fully cut an M40 x 1mm
but i turned the lathe by hand as it was a short thread.Under diary of
an ER32 collet chuck. Barry

 

[chucketn]

My MicroMark 7x14 has a thread dial, and it works. I have cut most of the common imperial threads and several metric, including the threads on the left end of the lathe spindle, M27x1.5, I believe. I made a spider that screws on the spindle in place of the outside(2nd) nut. I made a spindle crank/wheel from a treadmill pulley to assist in threading to a shoulder. I've cut inside threads, and left hand threads.
My most recent mod was to add a speed reduction/torque increasing jack shaft. Though it works good, I don't have enough time on it to decide if it's staying. I built the jackshaft after having issues with the speed controller. Burned the leads of the big diodes, and kept blowing fuses. All fixed now.

Chuck

 

[Cogsy]

I think a thread dial is an optional extra but I have cut many threads using the procedure Barry describes where you don't disengage the half nuts and just reverse the lathe to get back to the start of the thread. It works fine.

 

[bmac2]

Can you cut threads with one of these mini lathes? This one has a complete set of change gears supplied with it, but there is no thread dial indicator. In the manual, it talks about threading and refers to "handle "A" in picture below", but there is no picture.

Hi Brian
I never used it but a friend of mine use to have one of those lathes, if that’s Busy Bees B2227L the threading indicator is an option.
http://www.busybeetools.com/products/thread-cutting-dial-indicator.html

 

[Brian Rupnow]

bmac--My own personal lathe is the 10" x 18" B2227L from busy Bee, and it comes with a threading dial as standard equipment. This little mini lath is for a customers project that I am building for him to turn motor commutators, and is #B1979C and it has no threading dial.---Brian