Unfortunately, I don't have a fully equipped shop, so I have to make do with what I have. Sound familiar, anyone? What I was wondering is how can I make notches in tubing without a tube notching machine like I see on the TV shows? I have a small bench grinder and a compressor and a compressed air grinder, but whenever I try to make a notch in a tube so it will fit another tube I never seem to get a good fit. Is there a simple way of doing this without having a special tool? If anyone has a way of making notches in the end of a tube that works well and doesn't require any special tools I'd sure like to know how to do it. Thanks.
I don't know of any hand methods with the tools you mention having at your disposal. I use a drill press with an appropriate-sized hole saw for short tubes: Chuck the saw in the drill press and clamp the tube on the table. Tilt the table to get the angle you want, and have at it. I've never needed to do it, but I think for tubes too long to fit in the drill press, they can be clamped to a lathe's top-slide. With a hole saw mounted in the chuck, the top slide is set to the desired angle and the tube is fed into the saw with the carriage. One would need to fabricate a special clamp for this operation.
Maybe you can use those methods as ideas to fabricate a jig for use with a hand drill?
This pipe notching fixture sold by HF requires a drill press. This is how I fit up pipe. I bit more work, perhaps, but the fit can be really nice. first download "Winmiter.exe" from
formatting link
Key in your pipe diameters and print out a template. Wrap this around your pipe and tape it in place. You can now rough cut the excess off with a saws-all (recipricating saw) Finish up the notch with your bench grinder and a course stone.
"Hawke" wrote in news: snipped-for-privacy@corp.supernews.com:
There are two freeware programs out there, Winmiter and Tubemiter, that make paper templates for notching tubes. You enter the diameters of each tube, the angle of intersect, wall thickness, and the offset of center lines. Then print out the template. The template in wrapped, and taped, around the end of the tube to be notched. You then grind out the notch right up to the line on the template. Perfect notches every time. I usually use a right angle grinder, but a bench grinder or air grinder should work.
I made a patio umbrella stand out of large EMT, with an "X" base and a vertical tube, from the junction of the "X", to hold the umbrella pole. The vertical required a two notchs, at right angles, to fit the junction of the "X". I printed two templates, and layed one on top of the other, with the top one shifted 1/2 a notch sideways. I then traced the bottom one onto the top. This gave me the a perfect double-notch template for the intersect of the 5 tubes. I'm not sure I would use a "tube notcher" if I had one. I'm not into mass production, don't need to buy different size hole saws for all the different tube diameters.
I'm in the process of attaching a piece of 1-1/4" pipe across the end of a
1-1/2"x3" rectangular steel tube at a right angle to the tube axis, centered on the 1-1/2 side and parallel to the 3" side. I used the papar template concept to make the notchs on the 1-1/2" sides, for the pipe to sit in. Perfect fit.
Hawke, I set up my mill when I'm doing a lot of tubes, but when I'm only doing one or two, or when the tube diameter is small and the fit has to be fettled anyway, I rough cut the notch with a hacksaw and finish with a file. Completely by hand. Unless I'd doing roll cage material (1.5" dia .125" wall stuff) I can have the tube finished faster than I could set up the mill to do the cut. So you really don't need special tools. An awful lot of race cars were made back in the sixties exactly this way. Carrol Smith recommends this way in one of the Race to Win books.
Hawke, you've already gotten many good replies, and I hesitate to add my relatively ignorant input ... but one thing that I wonder about is if the bench grinder makes it harder to do -- I would think the relatively wide stone would get in the way.
I've not had too many occasions to make a notch, but generally have had good results by cutting the tube square, holding it to the piece to which it will be attached, and draw around it, using soapstone held away a bit by a finger (similar to how a carpenter will cope a joint using dividers). It gives only a rough guide, but I clamp it and grind close to the line using a 4-1/2" angle grinder -- a much narrower grinding wheel, allowing me to get into where I need to more easily. Also, by holding the grinding wheel diagonally, I can approximate a smooth curve of different diameters. Test the fit and adjust.
Now that I've described the process, it sounds like a lot more work than it really is, at least when only doing a tube or two. Also, I have to say that I've only needed to join tube at right angles -- if I needed to do some complicated compound angles, I'd probably have to go the software route.
I use winmiter.exe and a 4.5" angle grinder. After I draw the cut line on the tubing with a Sharpie, I use the angle grinder to remove everything on one side of the line.
I have read that using a lathe with an end mill(?) bit will give precise fishmouth cuts. I would like to try it if I ever build a bicycle frame.
One can dress a grinding wheel either rounded or to a sort of rounded point. You'll burn through a set of dressing wheels, but it works great for notching tubing that isn't too thick (aircraft 4130 tubing).
When practicing on thin-wall 4130, I began with whatever cheap gray wheel came with the grinder in nearly new condition. After limping fairly successfully through half a dozen or so cluster joints, the wheel had worn to the shape I needed. Didn't bother my dresser at all.
I'll let you have my used tube notcher for $25 plus shipping.
I found it easier to just shape the tube on a large grinder as none of my joints were the same. See my web page and click on engine to see all the notching I did for the engine mount.
Bart
Bart D. Hull snipped-for-privacy@inficad.com Tempe, Arizona
My thanks to everyone that contributed their ideas on tube notching. As I suspected there are a number of ways to do it. Unfortunately, some of the suggestions make me want to see in person how you do it. Like this description of using a hacksaw to cut the notch. Maybe it's just me but how do you cut a curved line in the end of a tube with a straight edged hack saw. I'm not seeing this in my mind. Anyway, at least I have a number of possibilities. Now it's just a matter of experimenting until I find the way that works the best for me.
I have been looking around on my computer and my shop computer for a little program I have that is great for this. You enter the size of both tubes/pipes, the angle(s) for them to be joined and the print out the templates on your printer. Wrap the template around the tube/pipe, transfer the lines and cut.
I think its called "Win Angle" or something simular. I know it around here somewhere, maybe on my laptop, if not I guess I will search some of the back-ups.
Yep - straight line through a tube yields a curve! Just cut two angles at
45 degrees back angle on the end of a tube, and you have a notch that can be easily cleaned up to fit onto another tube at 90 degrees. If you want the join to be at another angle you rotate the angles so that the "90" is offset. A lot easier to do that to describe, and you can use a chop-saw to avoid the manual hacksawing if you want to...
Okay, now I understand what is meant by cutting the curve with a hacksaw or straight edge. I also have a chopsaw so I see how that would make a 45 degree cut real easy. The only thing is I don't think I would want to use the blade I have on the saw, which is for wood. I don't think that blade would work on metal, at least not for long. What kind of blade do you want to get for cutting metal?
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