Notching tube with bandsaw

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A year or more ago, some one posted up a chart for cutting fishmouth in tubing on a bandsaw. I cant find the thread now. Does anyone happen to have it saved and can point me to it?ThanksSafety 3rdGump
Reply:halfway down the pagehttp://www.pirate4x4.com/tech/billavista/Links/
Reply:BillaVista's articles are always great, and he's quite prolific, well worth reading.However, when I spent all my free time in the world of rock crawlers that started from the time when highly modified full bodied trucks and ridiculous exocages were the pinnacle of rock crawlers up till the time when "mood buggies" took over and I lost interest, somewhere in there I ran across a simple "rule of thumb" formula that worked astoundingly well.  Basically the origin and gist of what appears in BillaVista's subsequent in depth article.tigweld:*The chop saw method, if understood , is a science. With known tube size and joint angle, tube can be notched with great accuracy. The notch is achieved by cutting two opposing angles on one end of a piece of tube, to form a point. The cross-section of this cut will be an elliptical cut due to the shape of the tube. Changes in both of the two angled cuts must be made for the intersection angle and the size of the two tubes being joined. The only real limitation is the max angle of the chop saw.*You start with what I call the base angle. This is the angle of both cuts if the joint was 90*. For an example, I am fitting Two tubes together that are both 1.75", at an 90* joint. The base angle, or the angle of both cuts is 28*. These two cuts must meet at a point, and the point must also be centered on the tube.*What if I want an 15* joint with my 1.75" tube???? You must start with your base angle, witch was 28* for 1.75"(remember above), and subtract15* from one cut, and add 15* to the other cut to form a perfect notch. So now I must make a 13* cut and an 43* cut , with the point centered on the tube. Perfect coped joint, with no grinding.*Remember your base angle will change with the tube being cut and the tube that you are fitting to.*Here are a few examples of base angles...*2.0" to 2.0" tube, base angle of 30**1.75" to 1.75" tube, base angle of 28**1.5" to 1.5" tube, base angle of 26**1.25" to 1.25" tube, base angle of 22.5**1" to 1" tube, Base angle of 20**Now to fit diffrent size tubes together*1.75" to 2" tube, base angle of 25**1.75" to 1.25" tube, base angle of 45**1.25" to 1.75 tube, base angle of 20**1" to 2" tube, base angle of 12*
Reply:Thank youSafety 3rdGump