# What brand name of Tap & Dies to buy??



## Hal (Oct 18, 2007)

I just have a few odds ends of taps, mostly old ones picked up at garage sales or auction buys and not in the best of shape.

I'd like to buy a set of nice tap and dies and was wondering what brands to look at and where you guys order from.

Brownells sell tap sets  and they also sell a premium tap made by R & N.
Has anyone used any of these taps and how do the preform??

Does anyone know of  the R & N co. and the address, phone # or web site?

Hal


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## mklotz (Oct 18, 2007)

If your intention is to build model engines, any set of taps and dies is probably not the best approach.  Models require small tapping gear.  T&D sets will include larger sizes that you'll seldom, if ever, use in engine modeling.

Moreover, engine modeling will often require specialty sizes (e.g., 6-40, 3/16 and 1/4 in 32 and 40 tpi) that won't be included in any set.

You're better off buying what you need on a one-by-one basis.  Places like MSC and Enco will get orders to you in a couple of days.

You mentioned Brownells.  They're an excellent source for oddball taps and dies because so many strange threads are used on firearms.  Look there, too, for other specialty tooling.
For instance, they were the only place I could find a 1/4", 60 degree dovetail cutter.

Other than Greenfield, I can't help much with manufacturers.  However, like most things, price is a good guide to quality.


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## Tin Falcon (Oct 18, 2007)

Hal:
 Marv is right . When I was first setting up shop I bought a craftsman set of taps and dies . A few get used. 
   Secondly most sets contain 4 flute hand taps. these are the only ones that most text books mentions. 
There are a world of better taps out there spiral flute for blind holes spiral point for through holes and and forming tap for malleable metals and plastic.
 and as an addition to specialty sizes mentioned by Marv. Most sets do not include miniature sizes like 000-120.,00-900-80. 1-72 , 2-56,3-48, 4-40. IIRC my set only goes to 6-32. 

BTW a little tip never tap a hole unless you have the hardware in hand to fit it. there is nothing worse than tapping a hole only to find it is difficult to get the screw to fit it DAMHIKT
Tin
edited to correct error. Thanks Marv


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## mklotz (Oct 18, 2007)

Hey, Tin, there is no 00-120.  The (decreasing size) progression goes 0-80, 00-90, 000-120, 0000-160.  The last two are watch-making stuff and you'll never need them unless you're building some awfully tiny stuff.  Most suppliers of metalworking tools won't carry 00-90 but you can find them at the better hobby stores.  They look like roughened sewing needles.

[Aside:  The formula for major diameter of numbered screws is:

D (in) = 0.060 + 0.013*N

where N is the screw number.  For the multi-zero sizes, count the number of zeroes, subtract one and enter that as a negative number in the formula.  Thus, the diameter of a 000-120 is

D = 0.060 + 0.013*(-2) = 0.060 - 0.026 = 0.034"]

Any small tap with 32 or 40 tpi will serve you well in the model engine world.  You may also want to pick up a 4-48 since that's the standard thread on the tip of a dial indicator.  Being able to make your own DI extensions is handy.  Get the die too and you can make custom points for your DIs.


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## ed miles (Oct 19, 2007)

The taps I use are from a smaller company here in Canada about 25 miles from home. Taylor Tool makes all sizes up to 4" & 90mm and the quality is first class. I do all of their grinding and turning spindle repairs which lets me get a good look how its done. They also have cnnections to other tap makers for any odd thread type not made here. They found a 1/2" 12 Whitworth tap needed to repair some bolt holes in a Town Woodhouse lathe in our shop.

Ed


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## Tin Falcon (Oct 19, 2007)

Marv is right that the 000-120  is for tiny stuff. The thimble-kin engine in steam Stirling book one is a plan that I have seen that uses it. for the most part 0-80 is the smallest you will use. and Likely not smaller that 2-56 very much.A lot of it depends on the size or scale of the model the designs and the preference  and skills of the designer. It may also be effected by the availability of taps and hardware in his shop. 
Depending on the application you can often go up or down a size if you are not worried about true scale. For example the PM resear engines with 1/2 bore use 4 # 5 screw to hold the heads or cap on elmers designs use 6 #2s so there is a lot of room for play here.
Tin


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## shred (Oct 19, 2007)

I've been buying two each of the small sizes.  That keeps me from breaking one, since we all know it's the tap you only have one of that breaks.  :wink:  Enco frequently runs sales on taps and the HSS ones have done ok for me.  Around here, #4 and #6 taps, nuts and screws are available in most hardware stores, but the odd sizes and tiny ones are specialty items, though some are available in hobby shops.


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## macona (Oct 23, 2007)

Make sure you get HSS taps and NOT carbon steel. Not worth the metal they are made from.  

If it is through hole use a gun tap. It pushes chips out the bottom and tap without reversing. 

Also 1/4-20 is the weakest tap out there due to the depth of threads vs dia. This problem is compounded if you use a 4 flute. Try buying two flutes if you can.

Also try thread forming taps. They are pretty nice. The form the metal into thread instead of cutting. Note that the drill size is bigger than cutting taps.

Any American brand is good. Greenfield, Cleveland, etc.

I have a PDF from an old magazine samewhere on why taps break. Ill have to see if I can find it.


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## macona (Nov 1, 2007)

Carbon steel last longer than HSS??? What world do you live in???

Use an solution of alum and water to dissolve the tap out when in aluminum or brass. Heating may help the reaction. Nitric acid also works.

Or use a carbide die drill and drill the tap out.


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## rake60 (Nov 1, 2007)

You may want to consider this little excerpt from Brownells tool catalog.
_"High Quality To Help You Do The Best Work 
We supply our taps in Carbon Steel whenever possible. If one 
should break off in a hole, the remains can be "shattered" with 
a punch for easy removal."_
An HSS tap broken off in an expensive firearm could be disastrous.

In the soft metals we use the most in model building, the price difference
for HSS isn't really worth the cost.  If most of your work is in steel alloys
then of course you would what to buy HSS.  It all comes down to what 
material you work in the most.  A carbon steel tap will work in 4140 steel
but it will take a good bit of its life with it.

Rick


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## shred (Nov 2, 2007)

rake60 said:
			
		

> A carbon steel tap will work in 4140 steel
> but it will take a good bit of its life with it.
> 
> Rick


Somewhere else on that site they claim one of their taps is so good it tapped four holes and still had some life left... eek, that's some hard steel.


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## rake60 (Nov 2, 2007)

A carbide salesman called 4140 the armpit of alloy steels. LOL
Yet, 80% of the new manufactured parts we make at work are 
cut from 4140 steel.

Generally cold roll steel like 1020 has a hardness around 143 Bhn
and 4140 is normally about 302 Bhn
It is considerably harder, and without a coolant supply it can be tough
to work with at home.  
As I said before, if your going to be tapping a lot of alloy steels go HSS
If your working mostly in brass, aluminum and cold roll steel, 
carbon steel taps will serve you well.

Rick


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## IanN (Nov 3, 2007)

Hi Macona,



			
				macona said:
			
		

> Carbon steel last longer than HSS??? What world do you live in???



I think the above means that you disagree with my comments.

Perhaps my post was not as clear as it should have been - At low temperature CS is harder wearing than HSS but the properties of CS degrade significantly at high temperature where as those of HSS do not.

I always uses taps and dies by hand and so high cutting speed and the resulting high temperatures are not an issue. I work with a bit of cast iron, some aluminium but mainly mild steel and brass - so processing strange steel alloys is not something I need to consider.

So I stand by my original statement that CS is a better option.

There is one area where HSS has an important advantage, however, and that is in the accuracy of the taps. This is not due to the material, but to the manufacturing process:

A HSS tap is formed by supporting a hard blank between centres, grinding the thread and then grinding the flutes. The resulting thread is inherently true to the centre axis of the tap.

CS taps are cut using a master die, the flutes are ground in and then the tap is heat treated. Although the heat treatment is carefully controlled the tap will suffer some slight distortion and so all CS taps are slightly banana shaped (within the limits specified by the manufacturer of course).

Consequently, if you want to sharpen a HSS tap you can mount it by its centres on your tool and cutter grinder and do the job - you will have more of a tricky job if you attempt to do this with a CS tap.

I do not have the facilities to re-grind taps, and even if I did, on many of my plug (bottom) taps I have ground off the male centre at the tip to allow the tap to get as near as possible to the bottom of blind holes.

Ian.


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