? aligning joints at either end?

Assume all tubing is same diameter. Two vertical piece 2' apart - your task is to O/A weld a piece of horizontal tubing between the two. You measure CL-CL between the two vertical pieces and cut your stock. You carefully grind a 'fishmouth' at one end. You are now ready to grind the 'fishmouth' at the other end. How do you assure your second 'fishmouth' is aligned with the first? - Mike

Reply to
mhorowit
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I lay out fishmouths starting with a paper template. I'd scribe a line on the horizontal tube, parallel with the tube, and then align a mark on my paper template to that line at both ends. That will get them layed out correctly. Cutting them is up to you. If the vertical pieces are clamped in alignment, and the horizontal piece is clamped correctly, then you should be able to use opposing tacks to get the piece fit up even if the fit isn't perfect, and fill any gaps with 6011 or whatever. - GWE

Reply to
Grant Erwin

There are a variety of ways but most are based on getting a line running down the length of the pipe as Grant mentioned. On such small pipe you might simply set the pipe on a flat surface, lay a sharpened soapstone on a block one inch high, and slide the block on the surface with the soapstone drawing a line on the side of the pipe. This way is a poor man's version of a surface plate and height guage. Another way would be to use a machinist's combination square set. Use the centering head and the square head on the same rule. Set the centering head at one end of the pipe and adjust until the bubble level in the square head shows level. Your rule is now standing vertical. Mark the pipe at several locations or just at the ends if that is all you need. As a side note: Generally you do not cut your piece to the length of CL toCL. You cut it shorter so that you avoid that knife edge at the lips of the fishmouth. The knife edge prevents good fusion to the tube. The small shoulder created is a better alternative and allows you to put in a nice weld. Randy

Reply to
Randy Zimmerman

--Assuming you're doing the cutting with the tube in a vise on a milling machine table, or other long table you can clamp a vee-block to the far end, making sure that it sits squarely on the table or a stack of shims. When the time comes to turn the piece around just move the shims to the other end of the table, set the clamped vee block on it, close the vise and you're ready to go.

Reply to
steamer

The easiest way is to wander over the "loud-mouth-know-it-all" with an innocent look on your face and ask him how he would do it. Stand patiently trying to keep the glazed look out of your eyes and when he is finished, tell him your not sure you understand, and would he please show you how to do it. After he gets started have you buddy excuate plan "B" and call to you telling you that they want you in the front office. Stay in the brake room enjoying your coffee and cake, until the it's done.

Q.E.D

Diamond Jim

Reply to
Diamond Jim

Try a small piece of angle iron layed on top of your pipe and scribe yourself a line the length of the pipe. Then do your layout.

Reply to
Jess

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