QCTP - Tool Holders

[T Bredehoft]

I'm green with envy, your skill and tools.

 

[chips&more]

Very Nice! And on a Smithy(?) to!

 

[caster]

Thanks all, yes its a Smithy at-300 I bought in the early 90's

Caster

 

[Andre]

Good work on those holders, consistent chamfers and surface finish. But whats really impressive is that you did it on a Smithy machine. Nice work!!!

 

[caster]

Although I finished the holders I still needed depth stops. I had some 1" round scrap laying around turned it to remove the rust, center drilled and knurled.



Drill and tap.



Now I had an opportunity to test the newly made parting holder. Align it with the chuck, part some, then chamfer.



Finish parting



Deburr and insert the tap to verify the thread did not get damage. Project complete as soon as I get some 1/4-20 nuts.



Caster

 

[brav65]

Great work, I am a new guy to this world and love to see real projects being completed. Thanks for sharing!

 

[cederholm]

Wow, those are very nice.

- Carl

 

[Rick Leslie]

Like everyone has said, nice work! And that was my first thought: on a Smithy... )

I've got to get busy making more holders as well. Thanks for taking the time to document your projects. I'm anxious to see what you come up with on the tangential holder.

Every time I go to use my lathe, my first thought is "I need more tool holders".

 

[Andre]

Never knurled before, but if you notice the tops of the diamonds on your knurl are flattened. Not quite sure but I believe that means you didn't go far enough in OR went too far.

Nice work on the holder depth stops, what will you use for the threaded rod? Allthread?

 

[caster]

The Smithy at-300 has been my only lathe/mill for the last 20+ years. The model I own is no longer manufactured. It was succeeded by the Midas model and I guess the Grizzly G4015Z (It looks pretty much the same) which are significantly improved. There were several challenges that I needed to overcome. The machine has metric lead screws but the dials are marked in imperial. Both the carriage and cross slide screws are 2mm pitch and the dials are graduated in 2 thou increments 80 thou for a full turn. Well 2/25.4=0.07874 but the dials indicate 80 thou, you lose 1 1/4 thou per turn. The quill dial graduations are 40 thou, difficult (impossible) to get thou accuracy. The dials are not accurate and difficult to work with. There is an inherent compromise when building a 3-in-1. Here the mill column is a square screw that allows the mill head to swing and be raised/lowered, its locked by being pinched by a single screw. This is not the most ridigit setup. It does not happen often, but often enough, when milling a large cut (which I learned to avoid) the mill head can slip. The quill is locked the same way as the mill head, a single screw pinching the column. Unfortunately after many years of use metal fatigue caused the quill lock to break, I had to fabricate a new pinch mechanism. Finally, the motor is designed to work both 220v/50hz and 120v/60hz. It has worked well and has been uneventful although the RPMs displayed are based on 50hz so all speeds are 20% faster than indicated. Not so much of a problem but threading is a challenge. I guess this was originally a 220v/50hz metric machine kludged to be 120v/60hz imperial, if it were kept as metric it would be an OK machine. These days digital calipers are inexpensive. I mounted one on the quill and another on the cross slide. I fabricated a carriage lock and mounted a dial indicator to measure the carriage movement, I can measure 1" movement accurately then I need to reposition. Having overcome these challenges I now can work accurately. It's a hobby to me and it took a long time to develop the craft but perseverance prevailed.

The thing to learn here is that no matter what you are dealt you can overcome. Innovation and ingenuity are key.




Caster