# Why is this 6-32 tap not a 6-32 tap?



## LVLAaron (Jul 27, 2022)

I got this fairly expensive 6-32 tap and it is clearly not 6-32...

The tap on the left is chinesium hardware store crap, and the one on the right is the 40 dollar tap from MSC. (https://www.mscdirect.com/product/details/07034291)

The cheap tap is "correct" and the other one is... what? What am I missing?


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## Jim F (Jul 27, 2022)

Expensive tap is an STI tap.
For installing thread inserts.


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## pontiac428 (Jul 27, 2022)

One is a #6 screw thread, the other is a 6mm x 32 tpi bah-stard thread?

Edit- Oh, snap!  Insert tap for the win!


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## LVLAaron (Jul 27, 2022)

Jim F said:


> Expensive tap is an STI tap.
> For installing thread inserts.



Doh! thanks!


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## LVLAaron (Jul 27, 2022)

Well, the horrible freight tap managed to tap it's 4 holes without breaking. I think the whole set paid for itself... Time to throw it away before something bad happens!


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## mattthemuppet2 (Jul 27, 2022)

weird that the Guhring tap doesn't have STI on the shank or package - all of the many thread insert taps I've come across do. That's what I look for whenever I have a "huh, that looks weird" tap moment.

btw, Aaron, if you need taps, I have lots


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## Illinoyance (Jul 27, 2022)

Nowhere in the MSC data is there any mention of STI.  My guess is the tap was mis-labeled.  Return it.


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## savarin (Jul 27, 2022)

LVLAaron said:


> Well, the horrible freight tap managed to tap it's 4 holes without breaking. I think the whole set paid for itself... Time to throw it away before something bad happens!


It they worked they cant be total crap so why throw them away, its a good excuse to build a simple spark eroder for removing broken taps just in case for the future.
My eroder has saved my bacon many a time.


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## LVLAaron (Jul 27, 2022)

Heh, i wont throw them all away... just the 6-32. These taps aren't great for cutting new threads. The 4th hole I could tell it was getting dull.  I got them a long time ago to chase some rusty threads on my jeep. 

I've been using usa made cobalt taps in the shop with fantastic luck.


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## Jim F (Jul 27, 2022)

Illinoyance said:


> Nowhere in the MSC data is there any mention of STI.  My guess is the tap was mis-labeled.  Return it.


Click on the link, it is in the title description.


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## JimDawson (Jul 27, 2022)

I'm going to guess that somebody put a 8-32 tap in a 6-32 box.


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## brino (Jul 27, 2022)

savarin said:


> My eroder has saved my bacon many a time.



........and when they are working right they sound like bacon frying too.

If only someone made an EDM electrode that smelled like bacon!

Brian


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## markba633csi (Jul 27, 2022)

The 6-32 size is prone to snapping especially in steel- I would toss the HF tap and count your blessings


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## graham-xrf (Jul 28, 2022)

savarin said:


> It they worked they cant be total crap so why throw them away, its a good excuse to build a simple spark eroder for removing broken taps just in case for the future.
> My eroder has saved my bacon many a time.


Do tell about using the rubbish tap for spark erosion?
Or maybe a link if you have posted before how this works.


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## savarin (Jul 28, 2022)

not using the tap Graham but building an eroder to burn out broken taps.








						Keyed Washer/spacer
					

Hey Sav, i have a win-win for you... tell swmbo, that you are working on a gift for her or someone she adores, and can't be disturbed because it's a surprise. she won't mess with you, you get to play in the shop for double the length of time because "i want it to be extra special and...




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from post 14
Read the lot as there were some gotchas.
Since then I have re wound the coil to get to the recommended values and it can run for around 15 mins before it gets too hot.
I cant believe how many times I've used it now. Very simple and cheap.


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## pontiac428 (Jul 28, 2022)




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## Eyerelief (Jul 28, 2022)

Yup
.
..
...
Double tap


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## maspann (Jul 28, 2022)

I would call MSC, they have always been good to deal with.


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## LVLAaron (Jul 28, 2022)

maspann said:


> I would call MSC, they have always been good to deal with.



It was my bad. It says STI tap in the description. I didn't know better.


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## maspann (Jul 28, 2022)

I'd still give them a call. I bet they will take care of you.


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## darkzero (Jul 28, 2022)

Maybe you can sell it to a Subaru guy.


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## jpackard56 (Jul 28, 2022)

maspann said:


> I'd still give them a call. I bet they will take care of you.


+ 1 on calling them
Jim


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## FOMOGO (Jul 29, 2022)

I rarely throw out a tap. Some of the cheap ones I will grind down for a bottoming tap on occasion, or if really trashed or broken, a cutting tool. Mike


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## Bi11Hudson (Jul 29, 2022)

Again late to the party, this is getting old. . . I apologize if I missed a point. I did read the first page, but it was a scan, an overview. I didn't read closely.

There are a few possibilities, the first that comes to mind is a tap for an insert like Heli-Coil. A  6-32 HeliCoil sounds silly, but I have seen such an animal in the mills.

Another possibility is an M3.5 tap, which is the same size. I don't recall the pitch, but it is an exact replacement for 6-32. I recently purchased one, although I haven't used it. It is marked on the shaft as M3.5. I acquired it as part of my small metric taps, completely forgetting that 3.5mm is 0.138 inches, which is the same as a Nr 6 screw.

In any case, if it were mine, I would identify it as "non standard" and hang on to it. A use might show up out of the blue one day.

.


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## Illinoyance (Jul 29, 2022)

Measure it.  Figure out what it is.  Maybe you can use it.  Otherwise send it back to MSC.


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## Reddinr (Jul 30, 2022)

> bah-stard thread?



 Where I'm from back east it is pronounced bah-stid thread or if you are a bit less east, bass-tid thread might fit in better.  Hope this is helpful.


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## Flyinfool (Jul 30, 2022)

Bi11Hudson said:


> There are a few possibilities, the first that comes to mind is a tap for an insert like Heli-Coil. A  6-32 HeliCoil sounds silly, but I have seen such an animal in the mills.




While a 6-32 Heli_Coil may sound silly. I have installed a Lot of 4-40 Heli-Coils and specified down to 2-56. Military equipment does not allow aluminum threaded holes. All AL parts with threaded holes must have inserts in in the hole.

I would just get a small pack of 6-32 inserts to go with that tap and you will then be prepaired for the day you strip a 6-32 hole or need a bit of extra thread strength.


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## Marv in Minn (Jul 30, 2022)

thank you for the info, now i know what happened to me.
i ordered a 12-24 tap from Amazon, no STI in the description. 





						Morse Cutting Tools 33874 Screw Thread Insert Spiral Point Plug Taps, High-Speed Steel, Bright Finish, H2 Pitch Diameter, 2 Flutes, 12-24 Size: Amazon.com: Industrial & Scientific
					

Morse Cutting Tools 33874 Screw Thread Insert Spiral Point Plug Taps, High-Speed Steel, Bright Finish, H2 Pitch Diameter, 2 Flutes, 12-24 Size: Amazon.com: Industrial & Scientific



					smile.amazon.com
				



now i looked it up in the Morse site, there the description says STI.
tap is marked STI as is the tap box.
thanks, Marv


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## BGHansen (Jul 30, 2022)

LVLAaron said:


> It was my bad. It says STI tap in the description. I didn't know better.


Been there, done that.  @brino figured out the problem with my project (link below).  I'd never heard of STI taps either.

Bruce










						POTD- PROJECT OF THE DAY: What Did You Make In Your Shop Today?
					

Water or diesel fuel, dependent of the need.




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## pontiac428 (Jul 30, 2022)

Reddinr said:


> Where I'm from back east it is pronounced bah-stid thread or if you are a bit less east, bass-tid thread might fit in better.  Hope this is helpful.


Oui, but in France they say bah-stard, ho ho.


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## savarin (Jul 30, 2022)

I thought they just called it a "merde" thread


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