Internal / external retractable screw cutting tool holder.

[thehomeengineer]

Hi All
I have completed all the machining. Therefore, this is the first photo of the prototype tool.

I did take the design one-step further; its design now allows the tool to retract on either internal or external screw cutting operations.
I have used a few commercial made items; bolts, dowels, Knob handle, grub screws, oil cups and square head tool post bolts and tee handle to suit (still waiting delivery) . Some of these items I could have made but the time to machine and material costs, it is not worth considering.
The next task is to test the Retracting Tool Holder on both internal and external threads and if all goes well I hope to put a pack together for other builders to make.
Photos of the build have been taken and hope to collate this into a pack with the drawings. In addition, a few of the drawings need amending over the next week to ensure everything is correct.
I will contact Jon to arrange to sell the drawings/pack on HMT. (not sure of the price yet).
Testing will take place this week and if all goes well I should have the pack ready in a couple more weeks’ time.
Thank you for taking the time to read.
The Home Engineer

[hook86]

Looks good. Any plans would like to make one myself.

[thehomeengineer]

Hi hook86
Hope to have the drawings ready in a couple of weeks’ time. I plan to test this holder during this time, to check I am happy with the design as this is the prototype. I hope to post a video of the tool in action this weekend.
Thank you for your interest and patience
The Home Engineer

[hook86]

Looking forward to see your vid an plans.

[DIYer]

Thanks thehomeengineer! We've added your Retractable Screw Cutting Tool to our Lathe Accessories category,
as well as to your builder page: thehomeengineer's Homemade Tools. Your receipt:

Retractable Screw Cutting Tool by thehomeengineer

tags: cutting tool

[Saltfever]

Is the big handle for rapid traverse and the knurled knob for fine feed? Its been a few months . . . any updates?

[thehomeengineer]

Hi Saltfever
Thank you again for your interest.
I have posted the drawings on HMT. http://www.homemadetools.net/forum/r...g-holder-66976
This is two videos showing the tool in action.

The long handle is for rapid travel and the knurled knob has two functions.
1. When screw cutting internally, the knurled knob acts as a stop. You set it so the tool can be retracted far enough back to clear the full cut thread depth but does not allow the back of the tool to hit the opposite side of the bore when retracted.
2. When externally screw cutting this is set to create a positive lock for the forward cam movement.
I have used the tool on many threads, it has saved a lot of time and the repeatability is excellent when cutting multiple threads of the same size/depth.
I hope this has answered your questions if not please contact me again.
The Home Engineer