Using an oxy-fuel Cutting Torch...in this case its oxygen and acetylene.
Oxy-fuel safety is a big deal. Of all the welding equipment there is, oxygen acetylene torch equipment training is probably the the most neglected....and this is the stuff most likely to hurt you.
This video and page is not intended to be a complete oxy-fuel safety course...just some tips on safety and how to get a good cut .
The best oxy-fuel safety DVD I have seen is from Smith torch Equipment and if you use oxy-fuel equipment, I highly encourage you to get the DVD and watch it. You can order it from sites like cyberweld, or weldfabulous but you can also get it on Amazon.
Being able to make a good clean cut using an oxygen acetylene Cutting Torch is mostly a matter of using the right size tip, the right gas pressures, and having a steady hand. There are folks who seem to be able to make a good cut no matter what...but the right tip and pressures make all the difference for most.
One size does not fit all when it comes to cutting tips. Use the right size tip for the thickness of metal.
How do you know what the right size tip is?
The best way is to consult the manufacturers guide. Smith, Victor, Harris, and other well known makers of cutting torches have plenty of information on tip sizes, oxyfuel safety, and setup shutdown procedures on their websites.
since there are differences in design of cutting torches, there are different settings that work best for each.
When you just plain cant get any information for the brand of cutting torch you are using, one way to determine the oxygen pressure is to use a drill index to determine the diameter of the center hole in a cutting tip. Thats the hole where the high velocity stream comes out to make the cut,...all the other holes are called preheat flame holes.
Once you know the drill size for the center hole in the cutting tip, you can use a welding reference book like the one in the video to get a ball park idea for pressure needed to make the cut.
Sometimes one tip might be rated for cutting different thicknesses of metal and therefore, have different pressure settings for thicker metal. I remember a booklet for Smith Cutting torches that listed the same tip size for 3/8" and 1/2" thick metal and listed about 40 psi for the thinner but 50 psi for the thicker metal using the same tip.
The Audel Pocket welding reference was recommended to me by someone so I figured I would buy it and check it out to see if I could recommend it.
Its actually very good. Its a good very small book with lots of charts for amperage settings, cutting torch tip information, electrode selection etc.
and its not very expensive.
When I can, I order used books from Amazon because I dont mind a note or two or bent pages. I make notes anyway and dog ear the pages too.
Anyway, most of the tips are in the video. I think I mentioned something about the drill size being a 1 ....thats what my drill index said and I forgot to mention it was metric...I think that makes it about a #60 if you are not a metric guy.
Hopefully, you got that. Since I also said it was about .040" . Looking for a good torch tip chart that I could share with you led me to this one at the airgas website
.... it looks like I was pushing the limits by cutting 3/4" with that tip but all I know is that it worked fine.
I was using my friends "victor knock-off" torch but it worked pretty good.
One very important item concerning oxy-fuel safety that I neglected is the fact the high pressure cylinders like oxygen will take off like a rocket if the valve gets knocked off. Sometimes a concrete wall will not even stop them....
So make sure to keep the valve covers on when hauling and its a really good idea to have guards in place around the gauges even when they are not being moved...just in case.