our builder makes lugs this way. you can see an example at
http://www.oldtowncyclery.com/shopframes.htm
scroll towards the bottom of the page and check out the headlug there.
it was made from tubing. more from necessity than anything i think. there
are few lug blanks to be had these days, or so i understand. i do know
haydens are available but they are thick and take more time to file than
making them from scratch. or so my builder says. he prefers making them
himself.
peace
sarah gibson
kansas city