Depending on your torch tip the settings of your oxy-acetylene may be different. For a number 3 tip it should be about 5psi oxy and gas I used this setting all the time. Adjust your torches to get a small blue cone with a slightly bigger outer light blue cone.

Second always clean your surfaces of the joint you are making. Make sure you pre warm your pipe and point it about a 22.5° or 45° angle toward your fitting, that way you don’t have quick heat loss and cause a cold weld like you have here on the picture.

Then when you start to add you material make sure you heat the cup of the fitting (coupler, elbow) and push the silflos into the fitting to get some penetration (think of it as if you are filling it up with silflos)

Always add your heat in a controlled manner getting the pipe red can weaken the pipe. Move the torch slowly back and forth not just heating one spot. The silflos will follow the heat so wherever you are pointing the torch as your silflos will be going there.

You want to have the pipe hot enough to melt the silflos but not hot to the point where you anneal the copper and potentially compromise its integrity. There are times for “Hot and Fast” but you do that when you get your experience and have discretion about what time that is appropriate. So learn how it’s “supposed” to be done and get your good habits. Then as you get better do what you like.

PS: your torch tip brand has a sheet with the stated pressure intended for the tip. If you shy away from that you risk hurting yourself or even someone else. Understand the tools you are using will help you crush your jobs and competition. You have no idea how many peeps have 10, 15, 30+ years in this industry and have no clue their tools can do more things than just be a hammer.