Anyone heard of 1 1/16-14 thread?

Im making an adapter for that Buffalo #18 drill press (two speeds forwards, two speeds backwards and a bunch of pully combinations

The spindle nose appears to be threaded 1 1/16 x 14

Machineries handbook didnt even mention that thread. I need to know the minor diameter so I can single point the inside of the adapter.


"She's (my daughter) already dating a sex offender. Better that than a republican fundie neocon fascist." FF, (alt.machines.cnc)

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Hey Gunner,

My MH (25th Edition) shows a chart (page 1638) labeled:

"American Standard Unified Inch Screw Thread Form Data"

One column in the chart is called:

"Depth of Sharp V-Thread" and notes that for any sharp V-thread it will be .86603 X Pitch

and in the column it shows that for a 14 TPI thread, the depth is .06186.

There are also columns for UN threads, Int and Ext.

I did find a reference in another book for a 1" x 14 TPI, but all references to the 1&1/16" was for 18 TPI Extra Fine.

H>Im making an adapter for that Buffalo #18 drill press (two speeds

Reply to
Brian Lawson

Oddball thread indeed. There's a couple tables in Machinery Handbook to help out. On pages 1713 and 1714 of the 26th if you have it.

For a theoretical thread with perfect 60 degree pointed top and bottom: H = 0.866 * pitch pitch for 14 TPI = 0.07143 (1/14) My California math gives H = 0.0618

The flat in the bottom of the thread has a max of 0.25 H.

So 0.75 H = 0.046

In conclusion, I'd reduce that major diameter by 50 thousands radius or 100 diameter. You could go a little smaller.


Reply to
Karl Townsend

1 1/16 x 14 tpi sounds like a custom thread.

i would first find a bolt with the same tpi and check it or use the three wire method to measure the exact thread height.

or if you got an extra piece of tube to try out than try this lil formula:

Maj dia - 1/tpi = min dia

ie 1.0625 - 1/14 = min dia

1.0625 - 0.071 = 0.991 dia

Try it and let me know how it works


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From my threads file:- Thread Dia/ Dia/ Pitch/ Pitch/ Core Core Depth/ Depth/ Name Inch mm TPI mm Dia/" Dia/mm Inch mm

3/4 Whitworth 1.0625 26.988 14.0 1.814 0.9735 24.727 0.0445 1.130 Pipe Thread

That is the only 1 1/16"x14 thread I can find. It might may to check the thread form :-(. If it's rounded it's Whitworth.

Regards Mark Rand RTFM

Reply to
Mark Rand

You might want to check :

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Half way down the page they have the calculations and constants needed to determine the minor diameter. Plus they have a online tap drill calculator if you want a rough guestamate. Just a quick mental calculation .9843" hole looks good.

Best Regards Tom.

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Reply to
Don Foreman

Hey, thanks!

Ill try to single point it first though. On the other hand..Ive not had a lot of luck doing ID threads recently...sigh. I may have to take the part to a clients shop and program the thread and run it on a CNC.


"At the core of liberalism is the spoiled child - miserable, as all spoiled children are, unsatisfied, demanding, ill-disciplined, despotic and useless. Liberalism is a philosphy of sniveling brats." -- P.J. O'Rourke

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Well duh, I guess I could have been a bit more responsive to your question. .

Here's what DoN's program sez for 14 pitch threads:

Sharp V Truncated single depth .0618 .0541 double depth .1237 .1082

29.5 deg feed .0710 .0622

The minor dia will be the major dia less the double depth. I use the "truncated" numbers with a sharp V bit.

These numbers are for exact geometry so you may want to fudge some clearance and tolerance allowances.

Reply to
Don Foreman

Is guestimation (erring on the side of caution) and test-fitting (with the part still in the lathe if the drill-press spindle comes off, or still in the chuck if you're confident it can be replaced sufficiently accurately) not an option? Only any good for a one-off, but it avoids most of the tedious maths and provided you take small cuts is pretty much guaranteed to work (eventually).


Reply to
Tim Auton

And -- if it is Whitworth, the included angle is 55 degrees, not the more common 60 degrees. This will throw off the calculations that some others have posted, which presume a 60 degree thread form.

Good Luck, DoN.

Reply to
DoN. Nichols

And -- my program only is designed to calculate 60 degree threads, and another article has suggested that it is actually a Whitworth thread, which will be a 55 degree angle instead.

Good Luck, DoN.

P.S. Don, thanks for mentioning my program.

Reply to
DoN. Nichols

Let's see, it is Buffalo Drill Press... Maybe it is a 27 X 1.75 mm thread.


Reply to
Pete Logghe

I owned a laundromat and in '95 I bought 12 GE topload washers which turned out to have more bugs than Win 95 which came out at the same time. I had to replace the tub in a washer because the brittle plastic that it was made of had been punctured by a semicurcular steel reinforcement from a bra. A large nut had to be removed to separate the agitator shaft from the tub. It was an aluminum nut on a steel shaft and the alkaline detergents had corroded it to the point that it would not unscrew, even with a 2' cheater bar. I had to drill a row of holes on each side of the nut and split it. The thread was 1 1/16-14 and was left hand. The nut was not an item that could be ordered separately so I had to make one. I threaded a dummy shaft using the thread depth measurements taken on the agitator shaft with the pointed jaws of a digital caliper. I then used the shaft as a gauge to thread the nut. If any of you guys get a GE washer that needs this type of repair, send it to the landfill instead. Engineman1

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