Anyone able to suggest how to make a custom tap and die?
I want to make a small diameter (about 0.060") wooden bolt, and the mating nut/threaded socket. The kicker is that I want it to be coarse threads - sorta like this.
I know that in theory it would be possible to turn threads on the soon-to-arrive Sherline lathe, but I’m stuck with how to make the socket it would thread into.
Would it be easier, maybe, to make your own set of these, for the size(s) you are interested in, with the equipment we have:
https://www.amazon.com/WoodRiver-Woodthreading-Kit-1-1-TPI/dp/B0039ZEW16
You could then replicate/fabricate as many screws/nuts as you wanted.
If you can turn the screw in wood, do the same with a steel or h4 brass rod, put a taper on it and use that as a tap. Might work.
I found this fascinating, even if it’s not how you would choose to do it…
http://www.pbs.org/woodwrightsshop/project-guides/making-wooden-screws/
In a nutshell, it’s a translation and embellishment on a plan by André Roubo from L’Art du Menuisier — The Art of the Joiner (Académie des Sciences, 1759) on how to make the tap (from steel) and die (with a steel cutter) and the accompanying wooden die box. It’s pretty slick. Sounds work intensive, but not undoable, and likely a bit of fun once you get it right…
The Sherline, while able to cut a number of different threads (and hence make taps) will still be limited to a fixed range. For instance it is not likely to be able to create 90.378 tpi threads. So most likely there will be commercial tap and dies available for your particular need, but as @Photomancer says, if you can turn the thread you can do so in steel and use it as a tap. When tapping wood, you don’t even need to create the reliefs in the cutting edges you do with other materials. Just create a metal screw and thread it into the wood.
Given the scale you work, this information may not be helpful, but Roy Underhill has produced a number of viodes describing the process of how threads were created in wood prior to the invention of the screw cutting lathe.
http://www.pbs.org/woodwrightsshop/project-guides/making-wooden-screws/
https://videos.popularwoodworking.com/courses/the-woodwrights-shop-s06-ep01-turning-of-the-screw
…
I’d love to have something like that, but I need to make a screw about 1/16" diameter.
yes…I am suggesting you make the threadbox and tap for the size you are interested in. Making these: 1) seems easier to me (even though I couldn’t do it if the fate of the universe depended on it); and 2) you would then be able to make as many nuts and bots at that size as you could eat in one sitting.
You missed the first line in the first post in the thread…
lol…you are right.
query: “I need to figure out how to [something]”
me: “I know…just do [that something].”
me: (proudly) “we’re having shake-n-bake for dinner and I helped!”
Makes sense. I sort of had in mind 24TPI on a 0.188" major diameter as my starting point. I want to make wooden bench screws. By my math, the depth of the pointy tool would be 0.032" (on the radius) leaving a sturdy 0.124" of stock remaining in the center.
I’ve been reading the instructions for the Sherline thread cutting attachment and I have some questions.
(a) Did we buy a thread cutting attachment for the Sherline?
(b) Assuming we did buy one, would it be possible to cut the aforementioned thread (i.e., 24TPI on 0.188" major dia)?
If this is successful, I’d also like to be able to cut 32TPI threads, and for grins let’s say that I’m willing to make something as large as 0.090" major diameter. The depth of the pointy tool should be 0.024" (on the radius) leaving about 0.052" of stock remaining in the center.
From the invoice @Photomancer posted, no we did not purchase the threading attachment.
Yes, it can cut those parameters as well as the 32 tpi threads.
The Sherline threading tools can cut between 5 TPI (Threads per Inch) and 80 TPI, either right hand or left hand. Keep in mind that the Spindle motor is dis-engaged for this operation, the Spindle and the Z Axis (along the bed) are geared together with a handle operated wheel.
Rich - have you ever done this on the Sherline? I’d be willing to buy the attachment, but I’m nervous about disassembling and reassembling the Sherline.
I’d turn one screw in (probably brass), and then use it as a tap (in wood). I’d also thread one matching screw in wood (but I’d turn the wooden one to diameter on my lathe to minimize the sawdust I’d have to clean up).
Sorry, I have never done any threading on the Sherline. I do not have that attachment at home.
Thanks anyway! 
There’s Chris Marlow small and then there’s everybody else small…
Not realizing this was an old thread, I nearly had a heart attack when I thought I am seeing Walter posting.
That warmed my heart. Thank you.
Did anyone ever get around to turning large threads? Would love to try and do this with a Delrin rod… like a 3/4” rod and like 3-6 tpi
In theory that would be something that could be done on the Colchester (which is not in service right now but should be soon).