Question about key duplication

[vitti]

taking one of the three edges of a triangle file to a grinder to remove the teeth along the edge will make it easy to widen a cut without making it deeper too. i don't remember where I read this tip but it worked great for me.

[Abus]

Agree that a chainsaw file is probably the best cheap option. Having said that, filing is sort of an art rather than a science, so basically you could use a variety of files and get a functioning key.

I prefer to either use a machinist's scriber to copy a line on to the blank from the original, or I use a sharpie. The whole smoking a key business, IMHO, is pretty messy and inefficient. Not to mention that the smoke comes off pretty easy in handling, etc.

[linty]

i cheated on that part of the course, I had to duplicate a key by hand for a mortise lock and i just took the plug out first :)

[WOT]

I guess I wouldn't mind having a file with the cross section of a code cutting wheel