Subject: Re: Tap and dies

From: Mike Rehmus <[email-masked]>
Date: 22 Mar 1995 17:45:08 GMT

[email-masked] (michael jensen) wrote:
 
The difference between a good general purpose tap and die and one specifically made for 
aluminum is moot when you are tapping by hand.

Michael,

After tapping with both types of tap into aluminum, I cannot agree 
with you.  An aluminum tap takes much less torque to drive, the
difference increases markedly with the size of the tapped hole.

1/4-20 is very noticable.  At 1/2 inch, the effect is startling.

Mike Rehmus

---

From: Mike Rehmus <[email-masked]>
Date: 22 Mar 1995 01:11:52 GMT

[email-masked] (David William Jenkins) wrote:

> 
> That sounds like you're saying British, etc. tools are better that
> those from the US of A.  Personally, I would put all 5 countries
> equal in quality, if you choose reputable makes.  I have a varied
> collection of taps & dies, carbon steel and HSS, most of which
> come from those 5 countries.  

Didn't say that at all.  At their best, they can match us on some items.

Mike

---

From: [email-masked] (Vincent Jesus)
Date: Mon, 20 Mar 1995 23:29:50 GMT

Jeff Hannon <[email-masked]> writes:

>Background: I'm pretty new to metalworking but have learned
>a lot by reading this group for about the last six months.

>I need to get a hand tap/die (3/8" - 14tpi) to do some engine
>rebuilding work that I'm doing. I would like to get something
>that is useful for future non-auto projects. Are taps/dies for
>aluminum different? (I have been told they are - my engine block
>is iron).

>I don't trust the quality of the taps I see at the auto parts
>stores or Sears, and I am completely overwhelmed by the
>number of different taps and dies in the Travers catalog I
>have.

>I'd like to buy good to high quality tools but I don't know what
>makes a good one and what doesn't in this case. What should I be
>looking for? Any brand/company recommendations? Should I go for
>one at a time as I need them or buy a set? I'm almost certain any
>set I buy wouldn't have the one I need for the next crisis.
>The most I could afford right now is around $200. 

>==
>Jeff Hannon
>Motorola Commercial Space
>[email-masked]

	Jeff,
   Your best bet is to buy HSS spiral point plug tap. Regardless os the 
material your tapping. The different types may only be beneficial in a 
production environment. You may also consider using tap magic( cutting 
fluid) to make hand tapping easier. They make these fluids for aluminum
and for steel. If you use the one for steel on aluminum it will eat the 
metal. Hope this helps.

---

From: [email-masked] (michael jensen)
Date: 24 Mar 1995 17:34:51 GMT

Mike Rehmus ([email-masked]) wrote:
: [email-masked] (michael jensen) wrote:
:  
: The difference between a good general purpose tap and die and one specifically made for 
: aluminum is moot when you are tapping by hand.

: Michael,

: After tapping with both types of tap into aluminum, I cannot agree 
: with you.  An aluminum tap takes much less torque to drive, the
: difference increases markedly with the size of the tapped hole.

: 1/4-20 is very noticable.  At 1/2 inch, the effect is startling.

: Mike Rehmus

Mike R;

     You have to take into account the original poster was originally 
going to use the tap and die for a iron engine.  In a perfect world we
would all have access to the tap or die designed for that material.  
My point, If you have limited funds you are better of with a general 
purpose tap and die then one specifically designed for a particullar 
material.  After all, if you have only a tap designed for cutting 
aluminum it will probabilty not work very well tapping stainless 
steel.  But, you could use that general purpose tap for stainless 
steel, aluminum, steel, etc..
     I stand by my point that it is a moot issue when you are tapping 
by hand using a good general purpose tap verse a aluminum tap.  If you are 
in a production enviroment that would be a different story 
altogeather. You will have reduced frictional forces using a aluminum 
tap to cut aluminum.  But a good general purpose tap that can cut 
steel will be strong enough to cut aluminum.  Also a general purpose 
tap is about 1/2 the price.

Mike J. 

--
Mike Jensen ([email-masked]) 
Chemistry Instrument Shop              
University of Nebraska - Lincoln
(402) 472-3542