Cutting & fishmouthing tube w/ a drill press?

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Forgive my ignorance, I am a metalworking novice... I need to cut 30 or so foot long pieces of 1 1/2" square tubing (mild steel, 1/8" wall). Both ends of every piece need to be fishmouthed to butt against the side of 2" round tubing. I was thinking about using a drill press and a 2" hole saw to do the cutting and fishmouthing as a single step. Would this work? (The pieces would be well clamped, and supported on either side by well-clamped wood blocks to keep everything in place).Sorry if this is too basic a question - this is only my second metalworking project, aside from a ton of sheet metal aluminum work. I have discovered the joys of welding so my rivet gun will see little action, and the parts are getting heavier, and more fun.As an aside, I don't own a drillpress but was thinking about getting a JET JDP-15MF (3/4 HP, 3 1/8" stroke).Thank you,Sam
Reply:I use a tubing notcher by JD squared. You can find them in the www.trick-tools.com . You may want to devise a clamp body that is made to fit a vise, and has round clamping surfaces to hold the tube secure. Then, a little cutting fluid, and low speed, and steady pressure. You will be on your way. If you have a lot of tube to notch, I higly suggest the TN-100. It will save you time, and it notches angles well.
Reply:Aside from the 'how to' I will adise against something as small as a 3/4 horse drill press if you plan on a steady diet of these types of projects. The larger hole saws eatup horse power quick if you need to do volume work or have a need ro hog something through. I have a 1 horse setting idle now that I considered on the border.
Reply:Why not use an angle grinder.  Should be pretty easy to get a good fit, especially since your notching square.  you can draw the radius and grind away.      Cover up well, wear a respirator, ear plugs, grab a seat and grind away.As stated above, consider how much you will be doing this stuff.
Reply:Tap, if I did that many with a grinder, I'd be violent by the end of it.   I still like using a saw fishmouth pipes. Fast and easy. With my cold saw, I can fishmouth my usual 1 1/4 sch 40 pipe in less than 20 seconds. As long as they don't have to be 100% perfect, then you could be even faster. It isn't the best method for TIG joints, but for stick and MIG joints, it is great. Can be done with a chopsaw as well, just not as fast.
Reply:If you cut the square tubing with your hole saw the ends of the square tube will be cut to a very thin point at the junction with the round tubing, when you weld the 2 pieces together you will be welding at the thinnest part of the square tube (like on the left in the diagram).  I think it would be better to cut the square tubing first, then notch it with your holesaw, leaving the thickness of the sides of the square tubing to weld to with a stronger weld.  It also leaves you a nice "V" to fill with weld (like on the right in the diagram).  It would save a lot of wear and tear on the holesaw and you! Attached ImagesLast edited by BigEd36; 07-30-2006 at 11:35 AM.When the  drops the  stops!Check out my website at:  Tombstone 180 ACHandler 120Millermatic 210Powermax 380Harris & Victor torchesSawzallChop Saw
Reply:Great info - thank all you fellas for helping me out. Great tip on thin ends, too - looks like I'll be bandsawing the pieces and then fishouthing them separately. Still not sure what I'll fishmouth with, but it sounds like I have a lot of good choices.Thanks again!Sam.
Reply:old days a piece of soap stone and a torch --a template
Reply:For some reason I thought the notches were going to be at 90 degrees.  Don't know why I assumed that.  Anyway with 1-1/2 against 2" there should not be much grinding.  If the material is mitered  first(as mentioned by BigEd) then notched then still should not me much grinding. I have also used a portable bandsaw to remove as much metal in the notch as possible, then clean it up with a grinder.