Pipe Coping Die Set- Help Identify

[pamike]

So I found a set of pipe coping dies that might work for a project I have. I picked up about 5000 lbs of 1 1/4" sch 10 and 1 1/2" sch 10 pipe a few months back and I have been looking for a cheap set of coping dies to do the notching. The die set is marked " 1 1/4 x.075 x 1 1/2". I am trying to determine if the markings are for pipe or tube, and to verify that they will work for my pipe
I had the seller take some measurements and the lower "bed saddle" for the pipe being notched is 1.2" wide and .44" deep. This arc size corresponds almost exactly to 1 1/4" pipe which measures 1.66" od. So I have no doubt that a 1 1/4" pipe would fit in the saddle.

The part I am confused about is the punch/notcher profile that does the notching is only 1.09" wide at the widest point. If this notch is really to saddle up to a 1 1/2" pipe (1.9" od) you would think that the punch would be as wide as possible and still fit inside the smaller 1 1/4" pipe. 1 1/4" sch 10 pipe has an ID of 1.442", so why isn't the notcher closer to the 1.442" dim instead of 1.09?
Any input? I have very little experience with pipe notching, so I am looking for some help...

 

[matt_i]

That is probably for tubing. On a "pipe" the ID is nominal and its all "floating" more or less. DOM (drawn over mandrel) or ERW (electric resistance welded) tube is built to tight tolerances where a wall thickness is specified. My other related guess is that if you went thinner than that, say to .062" wall the tube would crush instead of being able to stand up and take the cutting force.

Another reason the notch portion isn't as wide is if one milled a pipe to a perfect half-moon circle the ends will be so thin and sharp they will disappear as soon as the arc is struck. I believe its a compromise to give you a balance of an edge thick enough to weld but not a super large gap that has to be filled up.

What are you going to drive this with, an ironworker?

 

[pamike]

The more I think about your comments the more I think you are right about the tubing vs pipe comment. I originally thought tubing but then when I got his measurements of the bed saddle it was a perfect pipe size. More than likely the manufacturer used a pipe size bed saddle since that saddle size doesn't have to be exact since the tube/pipe will self center in the bottom. The actual cutter is the important part...
So, if they are made for tubing size of 1 1/4 and 1 1/2 od they probably wont work well for my pipe sizes of 1.66 and 1.9 od..
I was planning to drive this with either our hydraulic press or our pressbrake.

 

[readhead]

You may be misreading the label. It appears that it is a special unit to notch 1/14" to fit on 1/2". That would take a very small bite out of the 1/14". None of ours were labeled but we only used pipe sizes for railing. That type of notcher is made to install in the punch station on an ironworker but we would use ours in a press if the IW was *******.

 

[pamike]

No, I understand that is what it is... I agree it would take a small bit out of the 1 1/4 dia as far as depth, but it should still be a fairly wide notch...
A little too much uncertainty for the $300/set the guy wants for them.

 

[readhead]

Is it near you to where you could see it operate?

 

[pamike]

No its not. Internet deal. That's why I am hesitant...

 

[joe49]

Why not ask the seller these questions.

 

[pamike]

Why not ask the seller these questions.

Seller doesn't know anything. It was a business liquidation and seller is just middle man.