Multistart Threading On Machining Lathe

[Oruc Gazi Kutluer]

Hello,

 

I am planning to make my pens as possible as custom made, so I need special metrics for threading.

There are many threading solutions, I know Tapping is one of them The matter is the taps and dies with triple/quatro leads are so expensive. They are made of (oftenly) HSS, that is why lifespans are not so long.

 

My commissioners are asking for usually 12mm, 13mm, 13.5mm, 14mm, 14,5mm and 15mm multistart barrel threads. The total price for a whole set is not so affordable recently.. That is why I decided to make them manually, I have some solutions to make it easy There are couple of videos and essays I ve found on web, they are all about metal threading. The materials we are using are not that much strong, mostly thel are brittle..

 

As I succeed to make a proper one, I am going to share all stages here. I am just curious if anybody made anything about this problem? Is there anything to be aware of before starting

[richardandtracy]

I have not had a lot of success multi-start threading on a lathe - basically I don't have the skills needed. As a result I use a small 3 axis cnc router/engraver and a program I wrote for PC's to generate the toolpath (available as a free download). See my website http://www.chestnutpens.co.uk/misc/thread.html

 

Little cnc packages like this: http://www.ebay.co.uk/itm/CNC-3040T-Router-Engraver-Engraving-Drilling-And-Milling-Machine-3040-Hello2usa-/321692867933 with Mach 3 ( http://www.machsupport.com/software/ and a thread mill ( http://www.ebay.co.uk/itm/151088585470 ) then a vertical collet clamp for the barrel/section: ( http://www.arceurotrade.co.uk/Catalogue/Collets/ER-Collet-Fixtures/ER32-Collet-Blocks ) and a set of ER32 collets (though er25 may just work). That will cost about the same as the range of taps & dies you suggested, but do every thread you may wish for.

 

Regards,

 

Richard

[More4dan]

Here is how I have made my own taps for specialty single lead taps. I plan to try the same technique for multi start threads. This method works without a mill. These are suitable for acrylics, aluminum, brass, and ebonite. They will work on Stainless Steel but are about at their limit. These were done on a manual metal lathe. I have done single point threading on the lathe for the external threads but is very time consuming and making dies is very difficult requiring a mill. I've since purchased tap and dies. You have to decide what your time is worth. If you have a CNC metal lathe you might consider single point threading of threads but the time on a manual lathe won't be worth it.

 

http://www.penturners.org/forum/f166/making-your-own-specialty-taps-bock-5-mm-139755/

Edited April 29, 2016 by More4dan

[Oruc Gazi Kutluer]

@richardandtracy Your work is great.. Fascinating I ll be considering about setting up this system. However, it needs a little bit of budget and experience with programming and coding In near future I ll take this system for my base

 

@More4dan I have tried this tecnique and you are right. This is time consuming.. I am planning to make it with thread cutters.. Regarding your taps, I preferred to make channels alongside the tapping threads like standard taps. It works fine, yet the problem is always dies as you mentioned

richardandtracy