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Easy way to get cleaner Oxy-Fuel cuts.

Posted: Mon Aug 31, 2020 12:38 am
by sbaker56
For those of you who might not already be aware of this trick and may have believe looking like it was cut using a dull beaver is an inevitability of using the process, you can improve cut quality greatly by simply using a straight edge. I've seen them built using angle iron with a piece of overhanging plate welded on, I've seen small square tubing used often, but I personally simply use a piece of 1/2 plate that happened to be laying around. The only modifications I made were to polish the edge with a 120 grit flap disc and chamfer the edges.
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My prefered method is to mark a soapstone line with a speed square and use a C clamp to clamp the bar aligned with your mark, though I'm using some vise grips here. I've also found a heavy application of soapstone to the bar greatly helps the side of the tip glide smoothly along the edge of the bar.
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While it takes a little time to set up, It can very drastically reduce the amount of grinding needed after cutting. Below are a piece of 3/8" plate and two pieces of a 1/2" thick grader blade which given the much higher carbon content does not torch cut nearly as well as mild steel does. Given that it doesn't grind so easily either a clean cut is very important.
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With a 1/8 welding rod for reference.
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It won't remove the human element entirely or the need to cut with a clean properly sized tip and the right pressure, you can see certain issues with my cuts from a combination of human error and not worrying about torch settings, but it's still a major help.

Re: Easy way to get cleaner Oxy-Fuel cuts.

Posted: Mon Aug 31, 2020 8:49 am
by cj737
I use a 2”x 0.5” x 48” bronze bar. Same principle as a straight edge, but due to its heft, it doesn’t budge easily and won’t be disturbed by the heat. I’ve had it for over 10 years and it still gets used on every straight cut.

Re: Easy way to get cleaner Oxy-Fuel cuts.

Posted: Mon Aug 31, 2020 8:45 pm
by sbaker56
I went with using a solid 1/2 piece of steel to avoid deforming it during longer cuts as well. A piece of copper or bronze I'd imagine would be ideal for heat dissipation, just hard to find.

Re: Easy way to get cleaner Oxy-Fuel cuts.

Posted: Tue Sep 01, 2020 11:48 am
by Josh646
I have been meaning to make a burn bar.

https://youtu.be/JwExFph3e10