45 degree joint vs butt joint

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Whats the opinion here on using a 45 degree joint vs butting tube steel? The reason I ask is my cutting skills seem to suck on the 45 degree end of things. The fence on my abrasive saw is a joke at any angle other than 90. Thanks
Reply:Nothing wrong with it as long as you cap the end of the tube to prevent crushing if a large load is place on the joint.  I have had experience with large tube such as 6, 8, 10, and 12 inch for large structures.  The 45 degree cut is often avoided because of welding code rules concerning butt joints without backing bars.
Reply:Originally Posted by chaznsc The fence on my abrasive saw is a joke at any angle other than 90. Thanks
Reply:There is a tendency for the chop saw to pull your material at angles other than 90. Use extra clamps on the vice. Are you cutting material to form a 90 or are you splicing yo for a longer run?Sent from my SPH-M830 using Tapatalk
Reply:Originally Posted by BistineauAre you using the scale on the saw to set the fence to 45*? If so that may be a big part of your problem. Use a speed square with a known Good 45* angle to set it and recheck it after tightening it. But I guess, really, either joint design is OK to use.
Reply:A bandsaw does much more accurate miters than an abrasive chop saw.  I have gotten good results using a fixed disk sander to adjust the angle properly.
Reply:Another thing to consider, though not really significant for one-off type work, is the time / material factor of miters vs butt joints.- It takes longer to cut a miter than a straight cut- It takes more filler, hence, more electricity and time to weld up mitersWith a miter, I think the end product looks better, and its more of a skill builder.In the words of a super-mod here, IMHO-AaronJet 17.5" Drill Press1942 South Bend 16x84 Lathe1980s Miller 320A / BP --- 2013 Power Mig 2562012 Jet 7x12 Horizontal BandsawVictor O/A Setup
Reply:Originally Posted by chaznscHow would I use my SS to set a more accurate blade angle?
Reply:I get good cuts with my chop saw at angles, but my trick is to check the angle of the fence with a degree measuring tool, and then I also draw a line on what I'm cutting with the same tool, then when I place the metal in the saw I double check that the angles match.I frequently use the stock clamp to get snug then use an "F" clamp to hold the piece in the saw.
Reply:Originally Posted by chaznscHow would I use my SS to set a more accurate blade angle?
Reply:Originally Posted by BistineauPretty much what TSCG13 has said. Put the SS between the blade and fence on the 45* side and tighten the fence. Double check the fence to blade angle after tightening to make sure it didn't move when you torqued up on the wrench. Also mark your cut peice to ensure the blade is inline with where you want the cut to be. I don't really trust the built in scales on saws like that. It is a mass production thing and subject to manufacturing errors. I use the SS on my circular saws and table saw too, to confirm I have a true 45* or 90* or use other accurate means for other angles.Have you been using just the built in scale on the saw?
Reply:I never move the fence, too much trouble. I use blocks clamped to the table with a vise grip that are the right angle. I just hold the metal tight to the block and cut and it's very near perfect every time.