Drillin' 'n' tappin 'n' tappin' 'n' drillin'

Drillin' 'n' tappin 'n' tappin' 'n' drillin'

Post by Bill Fulme » Tue, 02 May 2000 04:00:00



I forgot the rest of the words...

Many thanks to engine guru George Aldrich for posting upon his website the
BEST cotton-pickin' drill & tap size chart this Cajun ever did saw...  Once
you figger out the color key, this rascal has it ALL, up to 1".....  Big
enuf for me...

http://rcplanet.com/aldrich_models/ .....  Just click the link..

Cheers,

Bill
http://rcplanet.com/grafix/

 
 
 

Drillin' 'n' tappin 'n' tappin' 'n' drillin'

Post by Roger Nea » Tue, 02 May 2000 04:00:00


The formula is so simple that the only thing I use charts for is to
convert drill sizes to decimal inch.  Tap drill size is the outside
diameter of the***minus the pitch (or 1/number thds/inch).  Example:
3/8-16 tap drill is 3/8 - 1/16 = 5/16", 1/4-20 tap drill is
1/4(.25)-1/20(.05)=.200".  This formula works for standard and metric
threads, the nice thing about metric is they give you the OD and the
pitch!  I saw this in a book in the library and haven't met many
machinists that knew of it.  It's good to know in case you have to tap
something that isn't on the chart, perhaps 1/4-32 glow plug threads.
--

Roger Neal

Quote:

> I forgot the rest of the words...

> Many thanks to engine guru George Aldrich for posting upon his website the
> BEST cotton-pickin' drill & tap size chart this Cajun ever did saw...  Once
> you figger out the color key, this rascal has it ALL, up to 1".....  Big
> enuf for me...

> http://www.FoundCollection.com/;Just click the link..

> Cheers,

> Bill
> http://www.FoundCollection.com/


 
 
 

Drillin' 'n' tappin 'n' tappin' 'n' drillin'

Post by Fred McClella » Tue, 02 May 2000 04:00:00


Quote:

>The formula is so simple that the only thing I use charts for is to

<SNIP>

DAMN !

Been struggling with that for YEARS !  Bet I've got a dozen charts
scattered around here and there.

THANKS !

 
 
 

Drillin' 'n' tappin 'n' tappin' 'n' drillin'

Post by Brad Wickize » Wed, 03 May 2000 04:00:00


Were you reading Machinery's Handbook by any chance?

later BraD


Quote:
> The formula is so simple that the only thing I use charts for is to
> convert drill sizes to decimal inch.  Tap drill size is the outside
> diameter of the***minus the pitch (or 1/number thds/inch).  Example:
> 3/8-16 tap drill is 3/8 - 1/16 = 5/16", 1/4-20 tap drill is
> 1/4(.25)-1/20(.05)=.200".  This formula works for standard and metric
> threads, the nice thing about metric is they give you the OD and the
> pitch!  I saw this in a book in the library and haven't met many
> machinists that knew of it.  It's good to know in case you have to tap
> something that isn't on the chart, perhaps 1/4-32 glow plug threads.
> --

> Roger Neal


> > I forgot the rest of the words...

> > Many thanks to engine guru George Aldrich for posting upon his website
the
> > BEST cotton-pickin' drill & tap size chart this Cajun ever did saw...
Once
> > you figger out the color key, this rascal has it ALL, up to 1".....  Big
> > enuf for me...

> > http://www.FoundCollection.com/;Just click the link..

> > Cheers,

> > Bill
> > http://www.FoundCollection.com/

 
 
 

Drillin' 'n' tappin 'n' tappin' 'n' drillin'

Post by Bob Cowel » Wed, 03 May 2000 04:00:00


Ok, that's cool,  BUT
what is the formula for the really useful sizes,
say 0-80 up to 10-24???
bob
Quote:

>The formula is so simple that the only thing I use charts for is to
>convert drill sizes to decimal inch.  Tap drill size is the outside
>diameter of the***minus the pitch (or 1/number thds/inch).  Example:
>3/8-16 tap drill is 3/8 - 1/16 = 5/16", 1/4-20 tap drill is
>1/4(.25)-1/20(.05)=.200".  This formula works for standard and metric
>threads, the nice thing about metric is they give you the OD and the
>pitch!  I saw this in a book in the library and haven't met many
>machinists that knew of it.  It's good to know in case you have to tap
>something that isn't on the chart, perhaps 1/4-32 glow plug threads.

 
 
 

Drillin' 'n' tappin 'n' tappin' 'n' drillin'

Post by C. Paradi » Thu, 04 May 2000 04:00:00


Most taps have the correct drill size stamped on them along with the tap
size and tpi.  At least the tap and die set I have.  Otherwise, there is
also a chart/table that comes with the set or go to the reference Bill
linked to.

Thanks Bill


Quote:
> I forgot the rest of the words...

> Many thanks to engine guru George Aldrich for posting upon his website the
> BEST cotton-pickin' drill & tap size chart this Cajun ever did saw...
Once
> you figger out the color key, this rascal has it ALL, up to 1".....  Big
> enuf for me...

> http://rcplanet.com/aldrich_models/ .....  Just click the link..

> Cheers,

> Bill
> http://rcplanet.com/grafix/

 
 
 

Drillin' 'n' tappin 'n' tappin' 'n' drillin'

Post by Roger Nea » Thu, 04 May 2000 04:00:00


Quote:

> Ok, that's cool,  BUT
> what is the formula for the really useful sizes,
> say 0-80 up to 10-24???
> bob

Well, for machine***number sizes, you need to either know the OD or
have a chart, and if you got to look up the OD in a chart, might as well
look up the tap drill size too!
--

Roger Neal

 
 
 

Drillin' 'n' tappin 'n' tappin' 'n' drillin'

Post by Roger Nea » Thu, 04 May 2000 04:00:00


Quote:

> Were you reading Machinery's Handbook by any chance?

> later BraD

No, it was some textbook at a community college, I was reading in the
library between classes. (was working as a machinist at the time)
--

Roger Neal

 
 
 

Drillin' 'n' tappin 'n' tappin' 'n' drillin'

Post by Bob Cowel » Thu, 04 May 2000 04:00:00


Well, you know,  I just {had} to ask  ;-)
I was hoping there was actually some method th the madness with those silly
numbered screws.
bob

Quote:


>> Ok, that's cool,  BUT
>> what is the formula for the really useful sizes,
>> say 0-80 up to 10-24???
>> bob

>Well, for machine***number sizes, you need to either know the OD or
>have a chart, and if you got to look up the OD in a chart, might as well
>look up the tap drill size too!