bikingman

Part 3, Torch Tips

1. What range of tips do you use for different frame building jobs? I guess that smaller tips should be used but look forward to hearing what other's think.

Look forward to reading this discussion and feel free to answer questions if you need any clarification.
Dan

JohnDThompson 

You'll want a number of sizes; big ones for bottom bracket shells and fork crowns, medium for lugs, and small for braze-ons. Exactly what types and sizes will depend on the torch and the fuel gas you use (e.g. acetylene or propane).

bikingman

Thanks, John, I guess the larger the mass of the tubes, the larger the tips should be, and if using propane, then even larger end bits should be used. It's going to be a journey to become comfortable with which tips to choose for different projects, especially when connecting tubes of different thicknesses.

Andrew R Stewart 

Tips are usually not referenced with their actual orifice diameters, like so much of a closed community the terms are part of the exclusion. The tip IDs that I use range from .025" to .060". Newbies usually find that a smaller tip is easier to "keep up with" (in that things happen slower) but this adds time to heat up and during brazing, flux has a time at temp aspect that drops off at some point. This is for OA not OP. ndy

bikingman

Thanks, Andrew for that insight. Will bear it in mind moving forward. Just a quick question regarding 'OA not OP.' I hear with propane; one should use a wider tip ID. Does your observation of newbs apply to OP? Do newbs prefer the slightly smaller tip using OP relative to a seasoned pro? Or are you referring to the time to heat up/brazing

Andrew R Stewart 

I would search this forum and Velocipede Salon for Doug Fattic's posts about OP. he's done a lot of homework and shared a lot.

My commit about a newbie using a smaller tip is that they don't have the skills to control things as they happen and often react after things get too hot. A smaller flame slows down this and allows their reactions to better keep pace. But the longer the time at heat the more the flux "wears out" and the metal goes through it's changes. This is why good instruction and practice are so important before a real frame is tried. Andy