Wood Taps , From Scratch

[Ulma Doctor]

How do you cut the relief and at what angle?

Hi Roadie, thank you for your interest!

i used a vertical mill with a 3/8" ball endmill and an inexpensive angle vise, like this one here

the relief angle was set at 10* on the vise, the hex end was held in the jaws horizontally.
i used a thin parallel to keep the tap level during the relief operation.
the tap was relieved off center, on 3 sides, to rake the cutting side teeth for aid in thread cutting.

 

[roadie33]

Thanks for the info Mike.
I need to make a 3/4 x 10 Tap also.

 

[Ulma Doctor]

You are very welcome,Mike
the 12L14 may not be the best choice of material for a tap that will see heavy use.
you may wish to make yours from 01 tool steel or other high carbon alloy if it's gonna see a lot of cellulose

 

[T Bredehoft]

Sure, wood needs more stock between the threads for strength. That's logical. I'm just using "finger tight" on my fixturing. I'd want stronger threads should I be putting any torque on them.

 

[Bill Gruby]

Run the tap thru one time. Coat the threads with CA Glue and tap them again after the glue dries. You will have threads of steel. We do this in Model Airplane building when threading plywood.

"Billy G"

 

[Steve Shannon]

Several companies make "wood hardener" which is less costly and easier to handle (at least for me) than CA.
A pint is about $13.


Steve Shannon

 

[Bill Gruby]

Be advised that most Wood Hardeners have a 24 hour drying time. If you re-Tap right away the threads will become difficult to separate. CA is now.

"Billy G"

 

[T Bredehoft]

Coat the threads with CA Glue and tap them again after the glue dries. You will have threads of steel.

Don't know why I didn't think of that....I use CA all the time in my 'factory'. It's like glass to saw through, ought to make really tough threads.

 

[Ulma Doctor]

well, i punched out a couple more wood taps in the last couple days
here's the update pictures...
i added a 1/2"-8tpi tap . i used 1/2" 12L14 hex
and a 1-1/8"-8 tpi , i used 1-3/8" 12L14 hex

here's a picture of the collection so far

thanks for looking!

 

[Kernbigo]

google x-press taps i think they would work great in wood, used to work for Besly Tap