How much life are you getting out of small taps?

[Twmaster]

I was working on a tool post for a small lathe today and needed to clean out some #10-32 threaded holes. I got the tap out of my storage box and noticed the thing was all chewed up on the cutting edges near the starting end of the thing. This tap -maybe- cut 10 or 12 holes in CR1018. The holes were even drilled just a hair oversize to aide in tapping....

12 holes?? Is this what I can expect from these small taps?

I only ask because I have much bigger taps (Fractional sizes) that I've had for years and made many many holes with that are still in good shape...

 

[rake60]

I have a 1"-8 tap in my tool box that may well be older than me and it still
works just fine. I also have five new 2-56 taps out of a lot box of twelve that
are less than a month old. Small taps dull much quicker than a larger tap.
If I get 6 successfully tapped holes from a small tap it is retired.

Rick

 

[Twmaster]

Ouch. That gets spendy if you work with lots of small holes...

 

[rake60]

Yes it is a spendy approach.

I'd rather spend $3 each on a lot box of a dozen new
taps than spend 3 days dissolving a broken tap out of
a nearly finished part.

For most tools the rule is use it until it breaks.
Taps are the exception. If you press them until they break
the result will have you talking to yourself in words that are
not allowed here.

Rick

 

[Twmaster]

Gotcha...

So there's no point in buying top drawer taps for these sizes. Of course I'm not saying buy Horrible Fright taps...

 

[Jasonb]

What are these taps made from, Here in the UK you the Commonly used BA sizes come in both cheap carbon steel that wears quickly or HSS ones that have a longer life though they are three or four times the price of CS.

Jason

 

[twineman]

As this is a hobby and I am in no hurry to finish a project I am always searching ebay for deals on items I know i will need in the future. I just bought 10 ea US made HSS 0-80 taper and bottoming taps for US $18.00 + shipping. I don't believe in paying full price for anything and am always looking for deals for the "disposable" items that I use every day. You just have to have patience.

Allen

 

[Twmaster]

Allen,

I do the same thing. Look for deals on stuff I use or can make work. I got lucky a while ago. Some lady who sells household stuff had listed a bunch of new US made end mills at $2 each. I bought every one she had.

Jason,

I suspect the tap I killed was just cheap carbon steel. Does not look like an HSS tool to me. Probably was something I bought at a DIY store some time ago. I have another that is TiN coated. Perhaps it will last better... Or not!

 

[jonesie]

if it is a commonly used tap spending the extra money for a good one will save in the end, also buying tin coated or nitrite coated alsos pays off. you can grind the ends off the chipped taps and make them bottom taps then you do not have to buy bottom taps, just be carefull you do not over heat them grinding then down. also not throwing them all together in one drawer will keep them from hitting against each other same for end mills

 

[ironman]

What is the best or most common way to dissolve a broken tap out of cast iron and CR steel? I have a few cylinder blocks I need to get taps out of if I can. thanks, ironman

 

[kvom]

On my halo build I tapped >200 2-56 holes in aluminum with the same HSS tap. ;D I use copious amounts of tap-magic.

 

[Jasonb]

What is the best or most common way to dissolve a broken tap out of cast iron and CR steel? I have a few cylinder blocks I need to get taps out of if I can. thanks, ironman

I don't think the Alum will work on ferrous metals as it will attack them in the same way it does the tap. Spark errosion maybe?

Jason

 

[BobWarfield]

I get pretty good life out of my taps. It's worth buying higher quality taps in my opinion. They seem to stay sharp longer. Plenty of opportunities to buy them on sale or via eBay as someone mentioned. It is surprising how much less effort is needed with a high quality tap than a hardware store tap. You can tell right away by the feel whether it is still sharp and cutting well.

Also consider roll forming taps. They are stronger and less likely to break off, though they're only good for alumuminum and softer steels.

Cheers,

BW

 

[jonesie]

using roll form taps are good but remember the tap drill size is different as there is no chip but the give a real strong thread.using a good tapping oil will also extend the life of the tap. slao when cleaning out threads on some parts they might be plated wih a hard platting or case hardened and that will also dull your tap real fast

 

[Lew Hartswick]

slao when cleaning out threads on some parts they might be plated wih a hard platting or case hardened and that will also dull your tap real fast

Or trying to "clean" the threads on a hardened tool holder.
...lew...