pipe development

[Joe W]

Can anyone help me I'm looking for a book on pipe development which will allow me to develop the shape of the inside thickness of a pipe on the outside thickness so I can do a square cut and then lay back the weld prep instead of having to do the outside then laying it back to fit the pipe it goes to cutting it square then putting the weld prep on
Joe

[ibewgypsie]

Fishmouthing and angular cutting so they weld together beveling before? is that what I understood you need?

You can purchase software from the model 3 bender site that can do that.

A machinist bible (About $50) has external diameters and internal diameters of normal pipe and tubing. Schedule 40,80, etc..

[Swarf&Sparks]

How big a pipe Joe? It's often easier to cut the fishmouth directly, with a hole saw in the lathe or mill. Just set the pipe at required angle in the mill vice, or a vice on your lathe cross slide.
I've used this method on small ( < 3") stainless tube. If you're cutting sched 40 or sich, the hole saw will require some support to stop it flexing away from the cut.
Rgds, Lin.

[Swarf&Sparks]

Sorry, maybe should have clarified that. Use a hole saw the same dia as the pipe you are welding onto and remove the drill from it, using only the saw to cut the fishmouth.

[ibewgypsie]

I got my jig-joiner from Speedway motors. Harbor freight has one too much cheaper. A floating arbor with holesaw and angle adjustment.

You still have to bevel the tubing to get a good weld in there. What a pain.. Mucho worse than the actual welding. Of course I was using .25 wall seamless the last thing I built.

I got enough tubing left to complete that next frame I wanna build.. that stuff is expensive..

[Swarf&Sparks]

Agreed re bevelling David. I use a burr in a little air die-grinder.

[Smokedaddy]

Joe,

What you're wanting to do is called a I.D. to O.D. "joint" (saddle, lateral, tee, off centered tee, off centered lateral etc.). I teach the exact class (one of many).

If you learn and understand the concept of parallel line developement, you can layout anything no matter how complex. If all you're wanting to accomplish are learning and understanding mitered cuts, it will be a piece of cake. There's nothing to those sort of layouts. Anyway, the best book on learning HOW to do the layout out is here:

http://www.pipefitter.com/BBFW.html

Here are a couple of pictures of an off centered saddle and concentric reducer that a couple of pipefitter apprentices were making (their first cutting and layout class). Crummy images but you'll get the point.

http://www.pbase.com/smokedaddy/image/45585774

http://www.pbase.com/smokedaddy/image/45585775

Oh and software exist too like EZ Pipe, which automatically generates templetes/patterns directly related to piping.

http://www.ezpipe.com/

I know you didn't ask, but there are quite a few companies that have patterns forsale too, like LEE's:

http://www.releeco.com/product.php

-SD:

[Smokedaddy]

Damn,

I should of mentioned that you can do the actual layout in AutoCAD (once you understand how) or any any 2D CAD program for that matter too. Then plot out the templete and wrap it around the pipe or tubing.

AutoCAD makes it easier IF (notice the if) you understand how to program in AutoLISP. If so, AutoCAD will genereate the pattern automatically in a second, then just plot it out. Of coures you have to a write program to automate this process, prompting for the necessary information (main size, branch size, etc.).

S'later,
-SD:

[This message has been edited by Smokedaddy (edited 07-01-2005).]

[Stepside]

Draw it full size 3D in Rhino and unroll the develomental surfaces. It is accurate enough that the paper thickness of the pattern is an issue.

[ibewgypsie]

Paper thickness? HUH? My ruler ain't got them lil bitty marks on it.. just the small ones.

Are ya building a watch out of tubing?

Ha.. yeah.. I still got a lot to learn from the fitters and ironworkers. I used to prefer to drink with the ironworkers, since the electricians are a bunch of prima-donna's.

[Joe W]

<font face="Verdana, Arial" size="2">Originally posted by Swarf&Sparks:
How big a pipe Joe? It's often easier to cut the fishmouth directly, with a hole saw in the lathe or mill. Just set the pipe at required angle in the mill vice, or a vice on your lathe cross slide.
I've used this method on small ( &lt; 3") stainless tube. If you're cutting sched 40 or sich, the hole saw will require some support to stop it flexing away from the cut.
Rgds, Lin.</font>

[Swarf&Sparks]

Got your email Joe. That *would* take a largeish hole saw