A big issue with the threads shown at 3:47 is that they are 4-start, not single start. There is nothing inherently wrong with a multi-start thread, indeed fountain pen caps often have a 3-start thread which makes screwing them on and off much quicker. But I think you should mention this as it is easier to cut a single start thread because there is more time to pull the tool away before it crashes. Indeed, later in the video (e.g. at 8:30 and 18:40) you cut multi-start male threads without mentioning it. These are completely useless unless the female thread is identical. I note at 27:00 that you screw on a lid with 8 or 9 turns of male thread visible. But it takes only 4 turns to do so. So, they are both double start. Which explains why the movements of the chasing tools were so fast. Another point: At 25:50 you skip over the cutting of the relief behind the male thread. At 27:20 you show how to get grain alignment between male and female. If the top and base screw together with no visible gap the method you show will not work. It simply shortens the male thread. Rather, you must slightly shorten the outside part of the base below the thread. (Or, equivalently but less conveniently, shorten the same part of the lid.) Only if this results in a gap between top and base should you shorten the male thread.
I always used an engine lathe when turning and threading wood. I needed regular threads for the parts I was making. These threads don't look that gaugeable.
thankyou, gives us the theory that Richard Raffan uses in his Box making video, as he uses a thread in one example of a box & lid. Also shows us what that "caliper" is for, saw it in a Timbecon catalogue , and the back of wood turning mag's, but never knew what it was for.
The thread location and end face of the female "TOP" and the thread location and thread relief shoulder are the "fixed" locations of these two pieces. Cutting the end face of the male piece should have no effect on radial alignment of the "TOP" unless the pieces are bottoming out internally. This is not what is shown. Good video on threading in general though.
Thanks for the tutorial, I have just ordered the 16tpi set, I guess I now have to order the gauge! The lathe you use looks beautiful like a Rolls! What make is it? Thanks again for a clear, concise instructional demo.
Hi anepictree...Glad you enjoyed the video..the lathe is an original classic Robert Sorby lathe...at the time it certainly was a Rolls Royce of woodturning lathes
@@robertsorbyengland Do you still make lathes? I guess I need to look on the internet. I m probably the only person in the world daft enough to fall in love with a tool for its colour :-) Thanks again - Peter
@@anepictree Hi...We stopped making lathes about 15 years ago to focus on our innovative tool production...but I know what you mean about the lathe...I used to love them too
31:03 says cocobolo was too soft to thread, so they used boxwood. Cocobolo has a slightly higher janka hardness rating. Can anyone provide some insight on this? Thanks!
Hi Nick...The video is quite old and the terminology that the presenter used can be misleading with the knowledge of the Janka scale as you have...Its not necessarily about the hardness of the wood, many hard woods are brittle and the grain will breakout, so they wouldn't be suitable for creating very fine detail, which is what you are trying to achieve when cutting threads...Boxwood is very fine grain and cuts very well hence the recommendation of using it for threads
@@robertsorbyengland gotcha. Thanks for clarifying. Sounds like it could be possible to consider a "dense" wood to be tight (fine) grained and hard on the Janka Scale...
You make it look so easy. True craftsman. I have never tried threading but after watching this video, I plan to give it a try. Thank you.
I have a set of 20 TPI Sorby chasing tools and love them. Threaded boxes are addictive. This is an excellent video.
A big issue with the threads shown at 3:47 is that they are 4-start, not single start. There is nothing inherently wrong with a multi-start thread, indeed fountain pen caps often have a 3-start thread which makes screwing them on and off much quicker. But I think you should mention this as it is easier to cut a single start thread because there is more time to pull the tool away before it crashes.
Indeed, later in the video (e.g. at 8:30 and 18:40) you cut multi-start male threads without mentioning it. These are completely useless unless the female thread is identical. I note at 27:00 that you screw on a lid with 8 or 9 turns of male thread visible. But it takes only 4 turns to do so. So, they are both double start. Which explains why the movements of the chasing tools were so fast.
Another point: At 25:50 you skip over the cutting of the relief behind the male thread.
At 27:20 you show how to get grain alignment between male and female. If the top and base screw together with no visible gap the method you show will not work. It simply shortens the male thread. Rather, you must slightly shorten the outside part of the base below the thread. (Or, equivalently but less conveniently, shorten the same part of the lid.) Only if this results in a gap between top and base should you shorten the male thread.
Excellent educational video, especially since I have ever turned 1 lidded box in a class. The added bonus of the mallet is great. Thankyou
Great video for this turner! Thank you so much, especially for the ways in which to adjust the fitting.
Something else to add to my Christmas list. A very helpful tutorial, thank you.
An excellent video,
Thanks
James
I always used an engine lathe when turning and threading wood. I needed regular threads for the parts I was making. These threads don't look that gaugeable.
thankyou, gives us the theory that Richard Raffan uses in his Box making video, as he uses a thread in one example of a box & lid.
Also shows us what that "caliper" is for, saw it in a Timbecon catalogue , and the back of wood turning mag's, but never knew what it was for.
Good video and a tool especially for the thread! For himself will try to make this, I can not buy here in Russia is very expensive
The thread location and end face of the female "TOP" and the thread location and thread relief shoulder are the "fixed" locations of these two pieces. Cutting the end face of the male piece should have no effect on radial alignment of the "TOP" unless the pieces are bottoming out internally. This is not what is shown. Good video on threading in general though.
I'v run a metal lathe, and that does not seem like it should work at all. Fine job.
Peak Humanity, I hope Mr. Sorby has a ton of descendants.
Makes it look easy
Great tutorial. But I am interested about the lathe. Is it a Sorby lathe? Are they still available?
Excellent video
Thanks for the tutorial, I have just ordered the 16tpi set, I guess I now have to order the gauge! The lathe you use looks beautiful like a Rolls! What make is it? Thanks again for a clear, concise instructional demo.
Hi anepictree...Glad you enjoyed the video..the lathe is an original classic Robert Sorby lathe...at the time it certainly was a Rolls Royce of woodturning lathes
@@robertsorbyengland Do you still make lathes? I guess I need to look on the internet. I m probably the only person in the world daft enough to fall in love with a tool for its colour :-) Thanks again - Peter
@@anepictree Hi...We stopped making lathes about 15 years ago to focus on our innovative tool production...but I know what you mean about the lathe...I used to love them too
I'll be honest the way this tool works is like witchcraft lol
Brilliant tutorial! ( It must be as i've added a comment ((totally out of character!)).
31:03 says cocobolo was too soft to thread, so they used boxwood. Cocobolo has a slightly higher janka hardness rating. Can anyone provide some insight on this? Thanks!
Hi Nick...The video is quite old and the terminology that the presenter used can be misleading with the knowledge of the Janka scale as you have...Its not necessarily about the hardness of the wood, many hard woods are brittle and the grain will breakout, so they wouldn't be suitable for creating very fine detail, which is what you are trying to achieve when cutting threads...Boxwood is very fine grain and cuts very well hence the recommendation of using it for threads
@@robertsorbyengland gotcha. Thanks for clarifying. Sounds like it could be possible to consider a "dense" wood to be tight (fine) grained and hard on the Janka Scale...
Thread chasing vido