To Lathe or Not to Lathe

As many of you know, I have been doing pretty much all of my lens conversions, modifications with glue, tape, and filter rings and a Dremel.  It's getting to the point where I am not happy about this BAND-AID solution any more.  I really want to use the right tools, such as a lathe, and a milling machine, but I have zero experience with either, so I started reading more about these tools, especially the mini-lathes.

To start with, what I want is really simple.  A tool that allows me to create a tube/ring that can be securely mounted on a lens, like an enlarging lens, and then mate to a helicoid or a lens mount, with precision, and if it looks nicer, that would be a bonus.  I probably don't even need to do threading initially, but I would love to be able to create threads like M39 or M42 that can easily work with other standard parts, but cutting threads is probably not easy with a mini-lathe.

The world of the lathe is full of confusion for beginners like me.  The dazzling variety of them is already headache inducing, but it's the accessories/tools needed to make the lathe work, that really screw my head and sometimes I feel I am slipping into a coma out of helplessness. One resource I highly recommend, is Frank Hoose, whose site www.mini-lathe.com is an excellent source of information.  However, I am more of a visual person, and Frank's Youtube videos are detailed, easy to understand, and well presented.  If you are thinking of getting a mini-lathe, be sure to check out his site/videos.  I learned a lot from him.  But, reading and watching video can only help so much.  There is no substitution for learning by doing, so I have decided to jump in with both feet :)

Buying a lathe is not like buying a camera or a lens, that you can hide from your significant other, so it's probably a good idea to clear that first with him/her.  I talked to my wife, with my oiled tongue, extolled the virtue of a machine that can do amazing things, like making useful household gadgets for the home.  Unbelievably, she went with it, and even encouraged, as long as I can cough up the money myself, which means I have to sell some of my toys, er, tools first :)

The tough part, of course, is deciding what to get.  I have a small house and space is limited.  Noise is a factor too as I share walls with neighbours. I don't want something so small that it's uses are severely limited, but on the other hand, not something very big and noisy.

At first, I thought about the micro lathe/mill combo that you can put together like Lego blocks. These usually have a small 30-60 Watt motor, which really is not suitable for working with metal.  But, they are very small, and relatively cheap at around $350.  Great for teaching kids or learning, but probably not able to do what I want.

My next target is the Taig Micro Lathe II.  This is an extremely popular lathe for home hobbyists and is available in Toronto through Lee Valley Tools.  It's very compact, well made and crafted in the USA.  The basic kit is reasonably priced and there are immensely vast number of accessories/tools available to make it into a full blown CNC lathe/mill machine.  But, in its basic form, it does not have power feed, thread cutting, etc.  Adding these features costs a lot of money and for beginners like me, might be a challenge to setup.

The last group of machines I consider is either a 7x12 or 7x14 mini lathe.  7x12 or 7x14 describes the size of material you can work with, which is 7 inch high by 12 or 14 inch long.  In practice, the length is 2 to 3 inches shorter, as you will need to account for the chuck and the centre that support the stock/work piece.  Usually, these machines have power feed and thread cutting with a variable speed DC motor.  On the Taig Micro Lathe II, speed is set by using different sized v-bells on an AC motor, although one can make a DC motor option for the Micro Lathe II.

What makes finding the right mini lathe so frustrating is the lack of availability of low end models in Toronto, unlike in the USA, our lucky southern neighbours, or our friends in China whom I envy for having such affordable and variety of lathes.  There used to be more variety of models and cost a lot less, when I looked at them few years ago, but now very few machine/tool shops stock low end metal lathes.  The lowest price ones I found is the Taig Micro Lathe II, costs around $380 without the $150 motor, and the King Canada 7x12 (probably made by Sieg of Shanghai, China) for a cool $1000 CAD. When the Micro Lathe II is configured to have the features of the 7x12 lathe, the price is probably more, or close to $1000.

I am leaning towards the 7x12 mini-lathe.  If I am not able to find a reasonably priced used one, this is probably the one I will get, but it will probably be a couple of months before I get one, and it would take even longer for me to get familiar with it to make it useful.  But, I am excited and look forward to the new tool.  There are so many possibilities!

True Love Cafe - Nikkor-H 48mm f2 rangefinder lens from Nikkorex 35 on Sony A7 at f2.

Adapting Refitted Rangefinder Lenses on the Sony A7

I have had quite a few Japanese rangefinder lenses that I took out of the cameras, but was never able to make them work.  Many of these are "fast" lenses, like the 45mm f1.9/2.0.  At the beginning, I didn't have enough experience removing the lenses and they pretty much all ended up having problems; shutter stayed shut, aperture not working, focusing mechanism could not be put back, etc. The most pressing problem is the very short flange distance, and a very large rear elements within the helicoid that interferes with the mount.

The short flange usually means the original focusing mechanism on the lens must be retained, but most of the old rangefinder lenses have very long minimum focus distance of about 0.8-1.0 meters (3 ft). I love to take close up pictures and this is just not very useful for me.  What I what is a method that allows me to focus very close, but also be able to attain infinity focus.  The answer is a helicoid with large opening, which allows the lens to go inside of the helicoid, and thus get closer to the sensor in order to achieve  infinity focus.  I found that most of these lenses have a barrel sizes just shy of 58mm, perfect to put a 58mm filter ring on the lens, and then mount the lens on the helicoid.

Rangefinder Lenses: On camera - Nikkor-H 48mm f2, on the right, Minolta Rokkor-PF 45mm f2, Fuji 4.5cm f1.9.

The focus helicoid I bought from the generic junk variant with a 58mm opening, and a 58mm mount. This helicoid has the same sh!t quality as the 17-32mm that I bought a few years ago.  When fully extended, there is a lot of play and it feels like it would break apart.  The German and Japanese have perfected the helicoid decades ago, and I just fail to see why we still have lousy quality on new helicoids.  But, helicoids with large opening is not easy to find and they are usually expensive, because most people would opt for the M42 version.  I just have to work with with I have.

So far, I have converted three lenses and they all work beautifully, except the Nikkor-H 48mm f2, which has the aperture stuck at wide open. The Fuji 4.5cm f1.9 and the Minolta Rokkor-PF 45mm f2 both works beautifully.  The lens can now focus very close, and yet I can still focus to infinity.

First snow storm in Toronto.  Shot through window - Fuji 4.5cm f1.9 & Sony A7.