Wood thread tap

[Blake M Williams]

I'm looking for a new tap.

I've acquired a couple of large wood thread taps. One is 2.5 inches. The smaller is 1.25 inches. The pro is that these arnt the easiest to find but the cons are that they are 60 degree teeth and I'm not a big fan of this tapered style. See picture.

I would like some help finding someone who can make a tap that is similar to the more modern ones. But for a 2.5 inch and teeth at 90 degrees. I like the newer style because it is easier to keep the tool lined up. I do not have any metal working mills or lathes, but if any of you know of anyone that can help me I would appreciate it.


Matthew

[Blake M Williams]

Something like this.

[Jim Koepke]

Blake, Do you intend to make one or two pieces or are you planning on going into production?

jtk

[Blake M Williams]

I'd definitely like to make more than one vise screw. Not a full scale production of screws, I'll leave that to the big companies, but I'd like to make a handful now and then.

[Jim Koepke]

Roy Underhill had an episode where he shows how to make your own screw thread box. My memory is a bit hazy as to weather or not he also showed how to make a tap.

The Spring 1977 issue of Fine Woodworking also has an eight page article on tap and die making. That particular issue has a large wooden screw and a block with internal threads on the cover.

Another source on this escapes me at the moment. My recollection is this was a one off method. The screw was cut first and the lead end was used to hold a cutter to cut internal threads. Then a temporary bolt was made using dowels to regulate the advancement of the cutter through the bolt as threads were being cut.

None of these would likely be as suitable for high production work as a steel tap.

jtk

[Blake M Williams]

Thank you. I have that fine woodworking article and a similar copy of Roy making a tap too. Using a tap like that works but you do have to run in through repeatedly while advancing the cutter each time.

[Jim Koepke]

[edited]
Using a tap like that works but you do have to run in through repeatedly while advancing the cutter each time.

The trick to avoid having to advance & repeat is to make the tap with more than one cutter. Each additional cutter can cut a little deeper.

The FWW article suggested using an old file as a source for cutter material. (this comment is for those who do not have a coppy of the FWW issue mentioned earlier)

jtk

[Blake M Williams]

The taps in my first post work BUT I would like to find someone who can make the different style and have the correct 90 degree thread profile. The taps I have are old but they are 60 degrees.

[Blake M Williams]

I found this one another member made a few years ago. Has anyone else made their own tap?

[Tom Bender]

Have made a thread chaser to clean up threads in cast iron. Started with a steel bolt with the correct threads. This may be a challenge for your case. Then ground a taper and filed in relief slots. Worked ok, never tried using on wood.