Hello folks, oxy-acet torches can be used to make our lives easier on a lot of different fronts. I was very fortunate when I initially started to learn about this trade to have folks around me who stressed the importance of many basic tools and techniques.
     It was my college instructors who pointed this one out to me and made a lasting impression to support a torch's versatility. We have all needed to remove any number of items from weldments or fabrications for any number of reasons. My experience here initially, was shown to me when I was working towards plate certifications with low-hydrogen electrodes. We had our 2G, 3G, and 4G plates with backing strips that we would be working on. After completing the welding it was beneficial to remove the backing before trying to either recut the plates so that they could be used again or to proceed with the process for testing to see how well we had done. Besides needing a way to efficiently remove the backing strips there are any number of other times when something needs to be removed, cleaned up, repaired, and other situations where having a clean and relatively smooth surface to work from can be a good thing. In certain applications, cutting the part to be removed as close to the finished surface without gouging it is the first step. Once a minimal amount of material is left you can proceed to the "scarfing" portion of the process. I sometimes use one of the scarfing tips with the bent tip to facilitate this process, in a pinch I just need to be more careful with the standard type tip. A tip which is slightly oversize from the one generally recommended for cutting a particular thickness usually works well for me. When I begin scarfing I no longer employ the cutting lever on the torch. Instead, I set the flame to it's neutral position as if I would be cutting and begin heating the area where I plan to start the process. Once I begin seeing the metal starting to melt I begin to adjust the torch slowly, to an oxidizing flame, while keeping the tip pointed in the direction that I would like the metal to be removed. Not enough oxygen won't move any material, too much oxygen and the flame will actually start cooling things off and won't remove any material, the right amount of oxygen and you will see a molten pool of sorts forming and by directing and angling the tip you will see material being moved out and ahead of the flame. Hot and ugly describes a lot of this process. When first employed you may look at the results and think you have made a terrible mistake, however, once you get the hang of it and employ a tack hammer, wire brush, and possibly a grinder to varying degrees, you will appreciate the use for this particular "tool". I have included a number of photos to give a bit better understanding of how this works.
     I will make this statement to go along with giving this method for a trade tool. With the amount of heating involved here there are a number of materials that would not be a good choice for using this. Any alloys that might be heat cycle/temperature sensitive should not have this used on them. You could end up with any number of metallurgical issues by employing this method.
     I have also used this for bearing race removal on shafts with really good success. If a bearing has failed in a shaft mounted situation the race which is left can be removed rather effortlessly and with out any damage to the shaft. By carefully starting the scarfing process on the outermost diameter of the bearing race and carefully washing and working your way towards the shaft you can thin that bearing race out enough and expand it enough with the heat that it will either slip-off or with a sharp rap of a hammer it will crack and open up enough that it can be removed. If you are going to hit it with anything just be sure to have good eye protection, ie, safety glasses, face shield, as bearings can certainly shatter in a scenario like this.
     The photos that I have included show a piece of plate with a number of weld beads that have been run on it's surface. I have included topical photos and some end/side photos, the first ones show the weld beads before any scarfing has taken place the other photos show the plate after scarfing has been done. The plate has been scraped and lightly tapped with a tack hammer and has been brushed with a hand wire brush.

Hopefully this might be something new for some of you out there or simply a refresher for others. If any of you have examples similar to this process I would enjoy seeing them included in this thread. Best regards, Allan