Tap&Die Question

[LURCHWV@BJS]

  I've been trying to find 8x32 &10x32tpi without any luck.  I found a set at Sears in "inch" is this the same as tpi?  The sales manager had no idea what I was talking about.


 tpi:thread or teeth per inch?


                      JW     Rich

[bluenoser]

Rich,

You shouldn't have any problem finding either if these taps since they are both standard (inch) sizes.

# 8 x 32 means a # 8 screw with 32 threads per inch, which is Unified or American National Coarse thread.  By contrast, a # 8 National Fine would have 36 threads per inch (TPI).  a # 8 screw has a major diameter of.1640".

# 10 x 32 is a # 10 screw with 32 threads per inch, which is a Unified or American National Fine Thread.  By contrast, a National Coarse # 10 would have 24 threads per inch (TPI).  A # 10 screw has a major diameter of .1900"

If I am not mistaken, the # refers to a standard American Wire Gauge (AWG) Designation.  Imperial or American National threads less than 1/4" in diameter are typically identified by the # system.   Metric is an entirely different animal.

Hope this helps
Laurie

[bluenoser]

Rich,

It just occurred to me you will likely need the correct drill bits too.

# 8 x 36  Tap drill for 75% thread is a #29 (.1360").  Clearance drill is # 19 (.1660").
# 8 x 32 Tap drill # 29.  Clearance drill # 19.

# 10 x 32 Tap Drill for 75% thread is a #20 (.1610"). Clearance drill is a # 11 (.1910")
# 10 x 24  Tap Drill # 25 (.1495").  Clearance drill # 11.

Laurie

[bob243]

These should be some of the easiest to find,  surprised Sears don't have them.    You can find them at a home building store,  or an electrical supply place (commonly used in this field as well) will have them as well.   If they don't have them,  MSC has a hundred different variations of a 8-32 or 10-32 tap 

[DutchGramps]

.... Metric is an entirely different animal....

A MUCH kinder animal....
When I see these # gauges: American, Brown&Sharpe, Birmingham or Stubs, W&M, Imperial, and the drills numbered in numbers and letters, I wonder how you ever succeeded in putting a man on the moon 
Well, I suppose once you're accustomed to it...
Metric Hans

[Doug Cline]

Rich,
The "inch" set at Sears was what you were looking for if it had those sizes in it, the front of the case should list the sizes included. Most hardware stores, big box stores, and other suppliers will also sell them individually, the Sears near me has individual taps and dies. The sales managers really should have been able to help you with this,

Doug

[LURCHWV@BJS]

 
  Thank you all,

         No one has ever explained thing to me to the extent that I get here.

          Thank you


             Rich

[dannybb55]

.... Metric is an entirely different animal....

A MUCH kinder animal....
When I see these # gauges: American, Brown&Sharpe, Birmingham or Stubs, W&M, Imperial, and the drills numbered in numbers and letters, I wonder how you ever succeeded in putting a man on the moon 
Well, I suppose once you're accustomed to it...
Metric Hans

  We had a crowd of metric rocket scientists. Von Braun, etc.

[Birddog6]

Any  NAPA  store will have the taps you require.  A Fastenal store will have them if one is near.  Just about any hardware store will have them.  Sears used to have them as well. Don't confuse them with questions  most are sales clerks & lucky they found their way to work, just tell them you need a 8-32 & a 10-32 tap.  Enco  & MSC has them as well, if you want to order them.  I prefer a 2 fluted spiral point tap.

[Acer Saccharum]

The two flute spiral point taps are the strongest and best performers in my experience.

[DutchGramps]

And if you can find them, take old fashioned tool steel ones, not HSS; you will know why, when you have to remove a broken HSS tap from that precious part you are working on...

[smshea]

You can find them almost anywhere, but Buy Good ones! I'd stay away from most of what the big box stores are selling. I've broke Vermont American Brand(Lowes) tapping soft brass. Hanson seems to last the longest for me.

[oldiemkr]

Grampshans,

No disrespect to you at all but we put men on the moon {and won WW11} with a lot of American toolmakers,machinists,welders ETC and ETC building equipment for our space program or our armed services. Most with the inch system.
I often wonder if we could repeat this these days.

Some years ago our Gov't made a deadline for everyone to go metric. That deadline went past quietly with little action when they found out what it was going to cost.

I always use HSS taps. 2 flute spiral point. Most of the carbon taps are of such low quality I could not use them.

[Dr. Tim-Boone]

Well I learned all I know about taps & Dies right here!!

Interesting story about Metric system in US that I heard. It is illustrative of change strategies.

Historically US and Canada used the inch system. In the 1700s (this makes the post period correct..and I think it might affect gunmakers) apparently Ben Franklin came back from the Court of France with the notion to use a metric standard in the US. It was proposed in Congress, but defeated. about every 40 years since then it has been brought up again and failed to pass. In the early 1900s the excuse was that we needed to teach everyone how to use metric system in our schools before making it a standard for the nation.....we still haven't done it........I wonder what that costs us as a nation??

The Canadians sometime in the mid 20th century required all signs and measures including thermometers to be both the inch system (read Fahrenheit) and the metric system. At the end of ten years everything was required to be metric. It worked and the Canadians use it........  I will resist the political statements and just say that sometimes when you want change to occur you have to find a way to enforce it....... my $.02 worth.

[DutchGramps]

Grampshans,

No disrespect to you at all but we put men on the moon {and won WW11} with a lot of American toolmakers,machinists,welders ETC and ETC building equipment for our space program or our armed services. Most with the inch system.
I often wonder if we could repeat this these days.
....
I always use HSS taps. 2 flute spiral point. Most of the carbon taps are of such low quality I could not use them.

Yes, I know, but perhaps you could have won it quicker...
In earnest: when we listened to the BBC in 1943, we heard that the USA were going to build thousands of ships, bombers that could take 10 ton bombs, and tens of thousands tanks there was widespread disbelief, that was simply not possible. Well, we proved to be a bit wrong, when we saw those bombers fly over our country, and for us, unloading tons of food in April 1945.
And my favourite ride is a slow, but very dependable 1942 BSA WDM20 despatch riders bike, designed entirely in Imperial measures (like 121/128"...), and tomorrow I will ride her during our National Liberation parade, together with jeeps, GMC, and even a Sherman
Taps: I am happy to have sets of toolmakers tool steel taps that I use since 1964; NEVER a problem, but I would not trust all the tool steel taps that are on sale...

[oldiemkr]

Grampshans,

I'd like to see a picture of that BSA. A past friend of mine was a BSA Rep. here in the states.

As I said no disrepect and I hope you did not take it that way. I used the inch system in machining and such for over 45 years and never felt a disadvantage.
The change here to metric has been a slow process and maybe it should be. I don't know how you could change over in a short span.

I hope you have a happy Liberation Day I can only imagine what it may mean to you and your neighbors. Its Election day here and I'm kind of celebrating that here.

[Dale Halterman]

Finding the taps should be easy, finding the proper drills may not be. When I was a kid you could buy wire gauge bits at two hardware stores in town, now I have to order them from McMaster Carr in New Jersey.

Dale H

[dannybb55]

 I have been thinking about linear measurements in relation to historical smithing. American gun/white/black smiths bought there taps and screw plates from the UK mostly, specially during the Rev War. I have a screwplate with a 3/8 by 16 cutter dovetailed in from the early 19th century and a galvanized carriage bolt threads right in. The arsenal at Springfield changed over to metric with the adoption of the 1795, French-style musket and all of those earlier muskets from Europe were not UK Imperial Measure, they were Dutch, Prussian, Hessian, French and Spanish Measure. Then there are the Penn Dutch, what did they use for a ruler?
 Spanish measure is even more complex. An horizontal measurement is in Varas and a vertical measure had another system. To make it worse, the Vara varied from colony to colony throughout the Americas and the Philipines. The old Holy Roman Empire had a fragmented standard so there wasn't even a standard German system. Even in the Great War the German Empire had, at the least, two Centigrade scales!
 I have an Iron smiths sway that was missing a screw. My friend David Stone, at the Tryon Palace blacksmith shop, found no metric or English commonality in the pitch or depth of the threads in the tool so he forged a set screw and ran it in white hot 4 or 5 times until it matched. That sway was a catalogue UK item from the early 19th century. UK threads were proprietary to factories and locales. The UK spanned the world but I'll bet 5 feet of wrought chain that there were Irish, Welsh, Scottish and Cornish measures until the end of the 19th Century.
 
       Consider all of this in Wonder and Despair.
                                        Danny

[jwh1947]

Like Scotty, I've encountered breakage with Vermont brand.  1/4 turn cut, clean and oil, as my old shop teacher reminded us impatient kids. I go sometimes closer to 1/8 turn.  Got some 1/2 decent replacements recently at Home Depot.  Often you can get the drill bit and tap together.  Incidentally, unless you have a machine shop, removing broken taps can get ugly.  Easy does it.

[44-henry]

I've often found brass to be worse to tap than some steels in that the taps seem to stick in the material. Use good tapping fluid (I like Tap Magic) and remember to go slow regardless of what style and brand tap you use.

[Steve-In]

Here are number thread major diameters.  #0 is .06.  The rest follow in .013 increments.  I have no idea why they went in .013 increments.

#0   0.06   #5   0.125   #9   0.177
#1   0.073   #6   0.138   #10   0.19
#2   0.086   #7   0.151   #11   0.203
#3   0.099   #8   0.164   #12   0.216
#4   0.112            

Metric threads are designated like this M6x1., M8x1.25.  the M being the diameter in millimeters the x being the distance it takes the thread to make 1 complete turn in millimeters.

A MACHINERY'S HANDBOOK is a good investment as it has all this info and much more.

[LURCHWV@BJS]

   We need another little yellow guy,  An exploding confused face.  There is WAYmore info about taps&dies than I ever expected.  Almost mindboggling.  I will try to absorb the info you all have bestowed upon me.  WOW


Rich

   P.S.  GrampHans,   I too would like to see your ride.  I love motorcycles myself.  May ride it to Dixons this year.

[Tomegad]

I do a lot of machining as a vocation and ad-vocation. I got into it from the need to make my own tooling, that said I recommend either Master Carr or MSC as a source for tap dies and drills. If they don"t have it they can get it.With a screw cutting lathe you can make your own taps ! Not cost effective unless it is a strange breed (say a 3/4 x 40 left hand tap)that would cost you  dearly. The whole question of screws and screw forms brings up the subject of the development of the screw cutting lathe . A fascinating topic best dealt with separately.

[bob243]

I've often found brass to be worse to tap than some steels in that the taps seem to stick in the material. Use good tapping fluid (I like Tap Magic) and remember to go slow regardless of what style and brand tap you use.

Brass can be fun to tap, right      

A bright finish spiral point (gun tap) is probably about the best..  Most of the various coatings or materials are not any help and sometimes a hinderance because they are too sharp. 
A threadforming tap works good with brass as well ( your not cutting, your forming them, so nothing to hang up or grab)     

As far as drilling, (another fun task with brass)  carbide is really your best bet (it is not as sharp).   But there are ways to sharpen a regular HSS bit that will keep it from grabbing.

[LURCHWV@BJS]

   I googled Tap&Die found a Chart that explains everything


            Thanx Guyz   Rich