Cocker Barrel Taps F/S Cheap on Ebay!

[ScatterPlot]

Found this link while surfing Ebay today (no I'm not affiliated with them in any way)

http://cgi.ebay.com/ws/eBayISAPI.dll...sPageName=WD1V

It's a 15/16"-20 tap- the size for Cocker barrel threads. I bought one, hopefully it will work OK. Note usually a set of these are like 80 bucks, you get a plug and a bottoming one- this one I'm not sure which it is, but it's also a rolling type, so I'm not sure if they have the different kinds like they do with thread cutting.

[RazorMonkey]

That's a crazy good deal...

[ICP]

It's a roll form tap.. It is made for automatic machines. Requires quite a bit of pressure to tap. And will not work like a regular tap would. That's why they are cheaper.

[ojhspyro89]

You could probably use it to chase your threads if you stripped them or cross threaded them if ya want though.

[ScatterPlot]

It's a roll form tap.. It is made for automatic machines. Requires quite a bit of pressure to tap. And will not work like a regular tap would. That's why they are cheaper.

I know it's a rolling tap, but why would it not work like a regular tap? I mean more pressure, so what? Little harder to turn and all, but that shouldn't be too much of a problem...

[ICP]

Because there is no cutting involved(or at least very little). There is no "begining" so to speak. They form threads, they don't cut them.

[ScatterPlot]

I realize that it doesn't actually "cut" them but why would that even matter? I don't know just a whole lot about this, but could I not still do them by hand?

[ICP]

Without cutting, you most likely won't be able to even turn it into whatever your trying to tap.

The starting hole size is smaller than what you will end up with after it's tapped. In order to get to that size, it has to cut on the way in. I'm trying to think of a better way to explain it. If I think of something, I'll reply here.

[ScatterPlot]

No, I get the idea of drill size and all, I was just saying that I think the rolling size of drill is a different size than the cutting size of tap drill. I do have a lathe, so I think I can get it going in OK, maybe not, I dunno, but I think I can get it going OK. I haven't used a rolling style tap before, so we'll see.

[ICP]

Never hurts to try. I've never tried using a roll tap in anything other than a screw machine or cnc lathe. You MAY be able to get it to work in a manual. Let me know for future reference if you don't mind.

[ScatterPlot]

Will do. This was more of a "good deal" buy than a "urgent need" buy, so it could take a while . I think I might try to make a twistlock-cocker adapter or two, cause it would be just cool, plus I have another project that I'm working on that needs doing